Shop All Carrier Proteins for Immunogen Preparation

Imject™ mcKLH Subunits, High Purity Research Grade (Thermo Scientific™)

Thermo Scientific Imject Mariculture KLH is a purified keyhole limpet hemocyanin carrier protein that enables simple preparation of highly effective immunogens with peptide antigens.

Features of Imject Mariculture KLH:

High-yield conjugation—each molecule of KLH contains hundreds of primary amines available for coupling haptens via EDC or NHS ester crosslinkers
Validated quality—purified and stabilized mariculture KLH maintains solubility in aqueous solutions, unlike traditional sources of the carrier protein
Sustainable source—KLH is harvested from select populations of the mollusk Megathura crenulata (keyhole limpet) that are grown in mariculture, not extracted from wild populations
Highly immunogenic—KLH has a high molecular mass (4.5 x 105 to 1.3 x 107 Daltons; aggregates of 350 and 390 kDa subunits) and elicits a stronger immune response than BSA or ovalbumin

KLH is the most popular and immunogenic carrier protein used for preparation of peptide antigens for immunization and antibody production. KLH preparations in phosphate buffer are ready for hapten-carrier conjugation via amine-reactive NHS-ester or glutaraldehyde crosslinking. Preparations in MES buffer are optimized for peptide-carrier conjugation via the carboxyl-reactive carbodiimide crosslinker called EDC (or EDAC).

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved.

Keyhole limpet hemocyanin (KLH) is widely used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for the purpose of antibody production. Because of its large mass and complexity, KLH elicits a stronger immune response than other carrier proteins. Because the protein is derived from a mollusk, it is phylogenetically distant from mammalian species and less likely to produce antibodies that will cross-react with typical target samples in assays.

Imject Mariculture KLH (mcKLH) is KLH that has been harvested from limpets grown in mariculture rather than captured from the wild. Imject mcKLH provides the highest possible immunogenicity; it is purified and lyophilized in buffers that optimize its stability and solubility for hapten conjugation. As a large protein, KLH has hundreds of primary amines and carboxyl groups that can be targeted for conjugation with NHS-ester, EDC, and other crosslinking reagents.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to the highly immunogenic KLH carrier protein for immunization and antibody production. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified mcKLH in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated mcKLH to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ mcKLH (in PBS)
Imject™ mcKLH (in MES Buffer)
Imject™ EDC mcKLH Spin Kit
Imject™ Purification Buffer Salts

Imject™ Ovalbumin (in PBS) (Thermo Scientific™)

Thermo Scientific Imject OVA is purified ovalbumin protein conveniently formulated for preparation of hapten-carrier conjugates.

Features of Imject OVA:

• Purified from chicken egg whites and lyophilized in phosphate buffered saline
• Single polypeptide protein with molecular mass of 45,000 Daltons
• Contains 20 lysine residues, most of which have primary amines that are capable of reacting with a conjugation reagent
• Contains 14 aspartic acid and 33 glutamic acid residues whose carboxyl groups account for the net negative charge (pI 4.63) of OVA
• Not as immunogenic as keyhole limpet hemocyanin (KLH) but more soluble in DMSO (dimethyl sulfoxide) for applications that require this solvent
• Useful as an irrelevant protein carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

Because ovalbumin is only weakly immunogenic, its primary use in antibody production workflows is as a secondary (independent) carrier protein to make antigens more amenable to antibody screening procedures. For example, peptide antigens are more easily coated in polystyrene microplates when conjugated to ovalbumin, thereby facilitating the screening of antisera that were produced using immunogen conjugates with KLH or other more immunogenic carrier protein.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved.

Ovalbumin (OVA), the most abundant protein in chicken egg whites, is a convenient protein for a variety of uses in the laboratory. The 45 kDa protein is not as immunogenic as other proteins, such as keyhole limpet hemocyanin (KLH). However, OVA's independent structure make it especially useful as a carrier for peptides and other small antigens that by themselves are difficult to manipulate in typical screening assays such as ELISA. Although it is more hydrophobic and less soluble in aqueous buffers than BSA, ovalbumin remains soluble in up to 70% DMSO, making it useful for conjugation with haptens that require DMSO for solubility. Ovalbumin contains numerous primary amines and carboxyl groups that can be targeted for conjugation with glutaraldehyde, NHS-ester, EDC and other crosslinking reagents.

Related Products
Imject™ Maleimide-Activated Ovalbumin

Imject™ mcKLH (in MES Buffer) (Thermo Scientific™)

Thermo Scientific Imject Mariculture KLH is a purified keyhole limpet hemocyanin carrier protein that enables simple preparation of highly effective immunogens with peptide antigens.

Features of Imject Mariculture KLH:

High-yield conjugation—each molecule of KLH contains hundreds of primary amines available for coupling haptens via EDC or NHS ester crosslinkers
Validated quality—purified and stabilized mariculture KLH maintains solubility in aqueous solutions, unlike traditional sources of the carrier protein
Sustainable source—KLH is harvested from select populations of the mollusk Megathura crenulata (keyhole limpet) that are grown in mariculture, not extracted from wild populations
Highly immunogenic—KLH has a high molecular mass (4.5 x 105 to 1.3 x 107 Daltons; aggregates of 350 and 390 kDa subunits) and elicits a stronger immune response than BSA or ovalbumin

KLH is the most popular and immunogenic carrier protein used for preparation of peptide antigens for immunization and antibody production. KLH preparations in phosphate buffer are ready for hapten-carrier conjugation via amine-reactive NHS-ester or glutaraldehyde crosslinking. Preparations in MES buffer are optimized for peptide-carrier conjugation via the carboxyl-reactive carbodiimide crosslinker called EDC (or EDAC).

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved.

Keyhole limpet hemocyanin (KLH) is widely used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for the purpose of antibody production. Because of its large mass and complexity, KLH elicits a stronger immune response than other carrier proteins. Because the protein is derived from a mollusk, it is phylogenetically distant from mammalian species and less likely to produce antibodies that will cross-react with typical target samples in assays.

Imject Mariculture KLH (mcKLH) is KLH that has been harvested from limpets grown in mariculture rather than captured from the wild. Imject mcKLH provides the highest possible immunogenicity; it is purified and lyophilized in buffers that optimize its stability and solubility for hapten conjugation. As a large protein, KLH has hundreds of primary amines and carboxyl groups that can be targeted for conjugation with NHS-ester, EDC, and other crosslinking reagents.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to the highly immunogenic KLH carrier protein for immunization and antibody production. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified mcKLH in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated mcKLH to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ mcKLH (in PBS)
Imject™ mcKLH Subunits, High Purity Research Grade
Imject™ EDC mcKLH Spin Kit
Imject™ Purification Buffer Salts

Imject™ Blue Carrier™ Protein (Thermo Scientific™)

Imject Blue Carrier Protein is a highly soluble, mollusk-derived hemocyanin that enable simple preparation of effective immunogens with amine- or carboxyl-peptide antigens.

Features of Imject Blue Carrier Protein:

High-yield conjugation—each molecule of CCH contains hundreds of primary amines available for coupling haptens via EDC or NHS ester crosslinkers
Validated quality—the immunogenic carrier protein is specially purified to ensure uniform chemical structure and solubility for consistent performance
Superior solubility—increased solubility compared to KLH allows Blue Carrier Protein to be used in a broader range of conjugation protocols to accommodate unusual or poorly soluble haptens
Highly immunogenic—provides essentially the same level of immunogenicity and phylogenetic distance as keyhole limpet hemocyanin (KLH)

Blue Carrier Protein is a purified preparation of Concholepas concholepas hemocyanin (CCH) that confers high immunogenicity to conjugated antigens for injection and immunization in antibody production procedures. The large protein exhibits most of the same immunogenic properties as the popular carrier protein, keyhole limpet hemocyanin (KLH). However, its signficantly better solubility provides greater flexibility in immunogen preparation protocols by allowing a broader range of buffer and pH conditions for coupling peptides, proteins and other haptens using classical crosslinkers such as glutaraldehyde, Sulfo-SMCC and EDC. The accompanying Thermo Scientific Imject EDC Blue Carrier Spin Kit provides for easy immunogen preparation.

Properties of Blue Carrier Protein:

Alternative names: Concholepas concholepas hemocyanin, CCH
Molecular weight: Whole molecule: ~ 8,000,000; Subunits: ~ 400,000 and ~ 350,000
Absorption: maxima 280nm, 350nm and 558nm
Extinction Coefficient (A 1 mg/mL solution): 1.4 @ 280nm; 0.35 @ 346nm
A280/A350 Ratio: ~ 4.0
Copper/protein ratio: ~ 16 Cu2+ per protein molecule
Isoelectric point: 6.0
Solubility: Soluble in aqueous buffers: pH 7.0-8.0
Stability: Stable in aqueous buffers: ~ pH 7.2 without Ca2+ or Mg2+

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Blue Carrier Protein is specially purified hemocyanin from the mollusk Concholepas concholepas. The CCH protein is composed of two very large polypeptide subunits (404/351 kDa) that form an extremely stable heterodidecameric structure even in the absence of divalent cations. (By contrast, KLH has a less stable and soluble homodidecameric structure). The complex molecular arrangement of CCH subunits contains diverse repeated antigenic structures that elicit a strong immune reaction mediated by T and B lymphocytes.

Because of their large size and molecular complexity, KLH and CCH hemocyanins are carrier proteins of choice for use as immunogens to produce antibodies against haptens and peptides. Moreover, studies suggest that the strong DTH immune response elicited by hemocyanins in animals and in humans has beneficial therapeutic effects in certain types of cancer. New developments in the immunotherapy of cancer have taken advantage of the unique immunogenic properties of hemocyanins in the development of novel conjugate vaccines for treatment of emerging diseases.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to BSA carrier protein. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified Blue Carrier in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated Blue Carrier to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ Blue Carrier™ Protein (in sterile PBS)
Imject™ EDC Blue Carrier™ Protein Spin Kit

Imject™ Maleimide-Activated Ovalbumin (Thermo Scientific™)

Thermo Scientific Imject Maleimide-Activated Ovalbumin is sulfhydryl-reactive ovalbumin (OVA) for hapten-carrier conjugation with cysteine-containing peptides and other thiolated antigens.

Features of Imject Maleimide-Activated Ovalbumin:

• Maleimide-Activated Ovalbumin, supplied lyophilized in PBS (pH 7.2) with stabilizer
• Activated with 5 to 15 moles of maleimide per mole of ovalbumin
• Ideal for conjugating cysteine-containing peptide antigens to make immunogen or screening target
• Conjugation reaction complete in 2 hours; results in stable, covalent thioether bonds
• Single polypeptide protein with molecular mass of 45,000 Daltons
• Contains 14 aspartic acid and 33 glutamic acid residues whose carboxyl groups account for the net negative charge (pI 4.63) of OVA
• Not as immunogenic as keyhole limpet hemocyanin (KLH) but more soluble in DMSO (dimethyl sulfoxide) for applications that require this solvent
• Useful as an irrelevant protein carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

This product consists of purified, carrier-grade ovalbumin that has been modified with SMCC crosslinker to attach maleimide groups capable of forming covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other molecules. Immunogens are easily prepared from peptide antigens that have been engineered with a terminal cysteine residue as a precise conjugation point. Several antigen molecules can be attached per carrier protein molecule without blocking intended epitopes by crosslinking to primary amines or carboxylates within the peptide sequence.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved.

Ovalbumin (OVA), the most abundant protein in chicken egg whites, is a convenient protein for a variety of uses in the laboratory. The 45kDa protein is sufficiently large and complex to be mildly immunogenic. Consequently, OVA can be used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for immunization. If not commonly used to prepare the primary immunogen, OVA is a popular carrier protein to make antigens more amenable to analysis (e.g., screening assays involving plate coating) of antibodies that were produced using KLH or other more immunogenic carrier protein.

Imject Ovalbumin is not as immunogenic as other proteins, such as keyhole limpet hemocyanin (KLH). However, OVA's independent structure make it especially useful as a carrier for peptides and other small antigens that by themselves are difficult to manipulate in typical screening assays such as ELISA. Although it is more hydrophobic and less soluble in aqueous buffers than BSA, ovalbumin remains soluble in up to 70% DMSO, making it useful for conjugation with haptens that require DMSO for solubility. Ovalbumin contains numerous primary amines, some of which have been modified to make Maleimide-Activated Ovalbumin.

Related Products
Imject™ Ovalbumin (in PBS)

Imject™ Maleimide-Activated mcKLH Spin Kit (Thermo Scientific™)

The Thermo Scientific Imject Maleimide-Activated mcKLH Spin Kit contains stabilized, lyophilized Maleimide-Activated mcKLH (in PBS with stabilizer) and accessory components to easily prepare ready-to-use immunogens for immunization. Our Imject Maleimide-Activated mcKLH enables conjugation of sulfhydryl-containing peptide haptens to the highly immunogenic keyhole limpet hemocyanin (KLH) carrier protein for immunization and antibody production.

Features of Imject Maleimide-Activated mcKLH:

Optimized activation—specifications require that each lot is activated with more than 400 moles of sulhydryl-reactive maleimide per mole of KLH, ensuring consistently high levels of conjugation
Sulfhydryl-reactive—engineered for conjugating cysteine-containing peptide antigens to make effective immunogens for high-titer antibody production
Simple, rapid procedure—complete the hapten-carrier conjugation reaction in two hours to yield sufficient immunogen for several injections and booster immunizations of host animals
High-quality carrier protein—KLH is isolated from the mollusk Megathura crenulata (keyhole limpet); mcKLH is a high-quality form of KLH that is harvested from limpets grown in mariculture
Highly immunogenic—KLH has a high molecular mass (4.5 x 105 to 1.3 x 107 Daltons; aggregates of 350 and 390 kDa subunits) and elicits a stronger immune response than BSA or ovalbumin
Excellent solubility—our preparations of mariculture KLH are more soluble than typical forms

The high-quality mariculture KLH is rendered sulfhydryl-reactive by chemical modification with Sulfo-SMCC crosslinker, and the resulting maleimide-activated protein is then stabilized and lyophilized in phosphate buffer. Maleimide groups form covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other thiol-containing haptens. Numerous antigen molecules can be conjugated to each KLH molecule to make them highly immunogenic and increase the likelihood of eliciting immunized animals to produce high-titer antisera to the epitopes of interest. Select from among several package sizes of activated KLH protein, or choose the complete conjugation kit that includes optimized buffers and trouble-free spin desalting columns.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Keyhole limpet hemocyanin (KLH) is widely used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for the purpose of antibody production. Because of its large mass and complexity, KLH elicits a stronger immune response than other carrier proteins. Because the protein is derived from a mollusk, it is phylogenetically distant from mammalian species and less likely to produce antibodies that will cross-react with typical target samples in assays.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ Maleimide-Activated mcKLH
Imject™ Maleimide PEGylated mcKLH
Imject™ Maleimide Conjugation Buffer

Imject™ Maleimide-Activated Blue Carrier™ Protein (Thermo Scientific™)

Thermo Scientific Imject Maleimide-Activated Blue Carrier Protein enables conjugation of sulfhydryl-containing peptide antigens to this soluble immunogenic carrier protein for immunization and effective antibody production.

Features of Imject Maleimide-Activated Blue Carrier Protein:

Optimized activation—specifications require that each lot is activated with more than 400 moles of sulhydryl-reactive maleimide per mole of carrier, ensuring consistently high levels of conjugation
Sulfhydryl-reactive—engineered for conjugating cysteine-containing peptide antigens to make effective immunogens for high-titer antibody production
Simple, rapid procedure—complete the hapten-carrier conjugation reaction in two hours to yield sufficient immunogen for several injections and booster immunizations of host animals
High-quality carrier protein—Blue Carrier Protein is ultrapure Concholepas concholepas hemocyanin (CCH) prepared from molluscan hemolymph
Highly immunogenic and soluble—CCH has a high molecular mass that elicits a stronger immune response than BSA or ovalbumin

Blue Carrier* Protein is a large hemocyanin that is highly immunogenic like keyhole limpet hemocyanin (KLH) yet is more soluble. The carrier is rendered sulfhydryl-reactive by chemical modification with Sulfo-SMCC crosslinker, and the resulting maleimide-activated protein is then stabilized and lyophilized in phosphate buffer. Maleimide groups form covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other thiol-containing haptens. Numerous antigen molecules can be conjugated to each Blue Carrier Protein molecule to make them highly immunogenic and increase the likelihood of eliciting immunized animals to produce high-titer antisera to the epitopes of interest.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Blue Carrier* Protein is specially purified hemocyanin from the mollusk Concholepas concholepas. The CCH protein is composed of two very large polypeptide subunits (404/351 kDa) that form an extremely stable heterodidecameric structure even in the absence of divalent cations. (By contrast, KLH has a less stable and soluble homodidecameric structure). The complex molecular arrangement of CCH subunits contains diverse repeated antigenic structures that elicit a strong immune reaction mediated by T and B lymphocytes.

Because of their large size and molecular complexity, KLH and CCH hemocyanins are carrier proteins of choice for use as immunogens to produce antibodies against haptens and peptides. Moreover, studies suggest that the strong DTH immune response elicited by hemocyanins in animals and in humans has beneficial therapeutic effects in certain types of cancer. New developments in the immunotherapy of cancer have taken advantage of the unique immunogenic properties of hemocyanins in the development of novel conjugate vaccines for treatment of emerging diseases.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ Maleimide-Activated Blue Carrier™ Protein

Imject™ BSA (in MES Buffer) (Thermo Scientific™)

Thermo Scientific Imject BSA in MES Buffer is purified bovine serum albumin carrier protein that enable simple preparation of effective immunogens with amine- or carboxyl-peptide antigens.

BSA is a popular immunogenic carrier protein used for preparation of peptide antigens for immunization and antibody production. Preparations in MES buffer are optimized for peptide-carrier conjugation via the carboxyl-reactive carbodiimide crosslinker called EDC (or EDAC).

Features of Imject BSA in MES:

High-yield conjugation—each molecule of 59 lysine residues, 30 to 35 of which have primary amines that are capable of reacting with a conjugation reagent
Validated quality—purified BSA (Fraction V) is available lyophilized and stabilized in PBS or MES buffer, ready for use in glutaraldehyde, NHS-ester or EDC crosslinking methods
Compatible solubility—numerous carboxyl groups account for the net negative charge (pI 5.1) of BSA and its high solubility, allowing its use in a broad range of conjugation conditions
Immunogenic—at 67 kDa, BSA is sufficiently large to function as the primary immunogen or it can be used as an irrelevant protein carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate hapten-carrier conjugation can be achieved. Imject BSA is very soluble in aqueous buffers and contains numerous primary amines and carboxyl groups that can be targeted for conjugation with glutaraldehyde, NHS esters, EDC and other crosslinking reagents. Imject BSA is purified and lyophilized in buffers that optimize its stability and solubility for hapten conjugation.

Bovine serum albumin (BSA) is a convenient protein for a variety of uses in the laboratory because, like most abundant plasma proteins, it is very stable and soluble. In addition, the 67 kDa protein is sufficiently large and complex to be fully immunogenic. Consequently, BSA is a popular carrier protein for conjugation to haptens and other weak antigens to make them more immunogenic for the purpose of antibody production. It also provides an independent hapten-carrier protein for microplate and other assay techniques required to screen antibodies produced using KLH or another more immunogenic carrier.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to BSA carrier protein. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified BSA in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated BSA to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ BSA (in PBS)
Imject™ EDC BSA Spin Kit

Imject™ EDC mcKLH Spin Kit (Thermo Scientific™)

The Thermo Scientific Imject EDC mcKLH Spin Kit contains packages of purified keyhole limpet hemocyanin carrier protein that enable simple preparation of highly effective immunogens with peptide antigens. This kit includes ready-to-use units of KLH carrier protein, optimized reaction buffers and trouble-free spin desalting columns for immunogen preparation using the EDC method.

KLH is the most popular and immunogenic carrier protein used for preparation of peptide antigens for immunization and antibody production. KLH preparations in phosphate buffer are ready for hapten-carrier conjugation via amine-reactive NHS-ester or glutaraldehyde crosslinking. Preparations in MES buffer are optimized for peptide-carrier conjugation via the carboxyl-reactive carbodiimide crosslinker called EDC (or EDAC).

Features Imject Mariculture KLH and kit:

Convenient kit—contains lyophilized mcKLH (in MES buffer), EDC crosslinker and accessories components to easily prepare ready-to-use immunogens for injection
High-yield conjugation—each molecule of KLH contains hundreds of primary amines available for coupling haptens via EDC or NHS ester crosslinkers
Validated quality—purified and stabilized mariculture KLH maintains solubility in aqueous solutions, unlike traditional sources of the carrier protein
Sustainable source—KLH is harvested from select populations of the mollusk Megathura crenulata (keyhole limpet) that are grown in mariculture, not extracted from wild populations
Highly immunogenic—KLH has a high molecular mass (4.5 x 105 to 1.3 x 107 Daltons; aggregates of 350 and 390 kDa subunits) and elicits a stronger immune response than BSA or ovalbumin

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved.

Keyhole limpet hemocyanin (KLH) is widely used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for the purpose of antibody production. Because of its large mass and complexity, KLH elicits a stronger immune response than other carrier proteins. Because the protein is derived from a mollusk, it is phylogenetically distant from mammalian species and less likely to produce antibodies that will cross-react with typical target samples in assays.

Imject Mariculture KLH (mcKLH) is KLH that has been harvested from limpets grown in mariculture rather than captured from the wild. Imject mcKLH provides the highest possible immunogenicity; it is purified and lyophilized in buffers that optimize its stability and solubility for hapten conjugation. As a large protein, KLH has hundreds of primary amines and carboxyl groups that can be targeted for conjugation with NHS-ester, EDC, and other crosslinking reagents.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to the highly immunogenic KLH carrier protein for immunization and antibody production. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified mcKLH in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated mcKLH to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ mcKLH (in PBS)
Imject™ mcKLH Subunits, High Purity Research Grade
Imject™ mcKLH (in MES Buffer)
Imject™ Purification Buffer Salts

Imject™ Maleimide-Activated BSA (Thermo Scientific™)

Thermo Scientific Imject Maleimide-Activated BSA enables conjugation of sulfhydryl-containing peptide antigens to immunogenic bovine serum albumin carrier protein for immunization and antibody production.

Features of Imject Maleimide-Activated BSA:

Optimized activation— specifications require that each lot is activated with 15 to 20 moles of sulhydryl-reactive maleimide per mole of BSA, ensuring consistently high levels of conjugation
Sulfhydryl-reactive— engineered for conjugating cysteine-containing peptide antigens to make effective immunogens for high-titer antibody production
Simple, rapid procedure— complete the hapten-carrier conjugation reaction in two hours to yield sufficient immunogen for several injections and booster immunizations of host animals
High-quality carrier protein— pure BSA (Fraction V) is activated using high-quality Thermo Scientific Sulfo-SMCC crosslinker and formulated to ensure high stability and consistent performance
Immunogenic and soluble— moderately immunogenic and highly soluble, BSA is useful for preparation of the primary immunogen or as an irrelevant hapten-carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

Purified, carrier-grade BSA is rendered sulfhydryl-reactive by chemical modification with Sulfo-SMCC crosslinker, and the resulting maleimide-activated protein is then stabilized and lyophilized in phosphate buffer. Maleimide groups form covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other thiol-containing haptens. Several antigen molecules can be conjugated to each BSA molecule to increase their immunogenicity and likelihood of eliciting immunized animals to produce high-titer antisera to the epitopes of interest. Select from among several package sizes of activated BSA protein, or choose the complete conjugation kit that includes optimized buffers and trouble-free spin desalting columns.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Bovine serum albumin (BSA) is a convenient protein for a variety of uses in the laboratory because, like most abundant plasma proteins, it is very stable and soluble. Numerous carboxyl groups account for the net negative charge (pI 5.1) of BSA and its high solubility (compare to positively-charged, cationized BSA). In addition, the 67kDa protein is sufficiently large and complex to be fully immunogenic. Consequently, BSA is a popular carrier protein for conjugation to haptens and other weak antigens to make them more immunogenic for the purpose of antibody production. If not used to prepare the primary immunogen, BSA is a useful carrier protein to make antigens more amenable to analysis (e.g., screening assays involving plate coating) of antibodies that were produced using KLH or another more immunogenic carrier protein.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ Maleimide-Activated BSA Spin Kit

Imject™ Alum Adjuvant (Thermo Scientific™)

Thermo Scientific Imject Alum Adjuvant is a formulation of aluminum hydroxide and magnesium hydroxide that effectively stimulates the immune response for antibody production procedures when mixed and injected with prepared immunogens.

Alum is considerably easier to mix with immunogens than Freund's adjuvants, as it does not require laborious emulsification. Although its effects are less pronounced compared to Freund's complete adjuvant (CFA), Imject Alum produces sufficient stimulation when used with complex immunogens (i.e., those that have been prepared as conjugates with KLH or other immunogenic carrier proteins).

Features of Pierce Imject Alum Adjuvant:

• Suspension of aluminum hydroxide and magnesium hydroxide
• Mild but effective adjuvant for substantial immunogens
• Ready to use: mix antigen directly with Imject Alum and inject
• The adjuvant of choice for allergy and immunogenicity testing with or without sensitization and challenge with fraction V ovalbumin (OVA) (see Moisan and Pongratz references)
• Disadvantage: does not elicit as strong an immune response as CFA; requires a strong immunogen

Adjuvants are nonspecific stimulators of the immune response. When mixed with an antigen or immunogen, adjuvants help to deposit or sequester the injected material thereby helping to increase antibody response. Adjuvants enhance the immune response to compounds that are already immunogenic; they do not confer immunogenicity to non-immunogenic haptens. To make prospective antigens more immunogenic, it is necessary to conjugate them to a carrier protein or some other complex, immunogenic molecule.

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Imject™ Freund's Incomplete Adjuvant (FIA)
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Imject™ Maleimide-Activated BSA Spin Kit (Thermo Scientific™)

The Thermo Scientific Imject Maleimide-Activated BSA Spin Kit contains stabilized, lyophilized Maleimide-Activated BSA (in PBS with stabilizer) and accessory components to easily prepare ready-to-use immunogens for immunization. Our Imject Maleimide-Activated BSA enables conjugation of sulfhydryl-containing peptide antigens to immunogenic bovine serum albumin carrier protein for immunization and antibody production.

Features of Imject Maleimide-Activated BSA:

Optimized activation— specifications require that each lot is activated with 15 to 20 moles of sulhydryl-reactive maleimide per mole of BSA, ensuring consistently high levels of conjugation
Sulfhydryl-reactive— engineered for conjugating cysteine-containing peptide antigens to make effective immunogens for high-titer antibody production
Simple, rapid procedure— complete the hapten-carrier conjugation reaction in two hours to yield sufficient immunogen for several injections and booster immunizations of host animals
High-quality carrier protein— pure BSA (Fraction V) is activated using high-quality Thermo Scientific Sulfo-SMCC crosslinker and formulated to ensure high stability and consistent performance
Immunogenic and soluble— moderately immunogenic and highly soluble, BSA is useful for preparation of the primary immunogen or as an irrelevant hapten-carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

Purified, carrier-grade BSA is rendered sulfhydryl-reactive by chemical modification with Sulfo-SMCC crosslinker, and the resulting maleimide-activated protein is then stabilized and lyophilized in phosphate buffer. Maleimide groups form covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other thiol-containing haptens. Several antigen molecules can be conjugated to each BSA molecule to increase their immunogenicity and likelihood of eliciting immunized animals to produce high-titer antisera to the epitopes of interest. Select from among several package sizes of activated BSA protein, or choose the complete conjugation kit that includes optimized buffers and trouble-free spin desalting columns.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Bovine serum albumin (BSA) is a convenient protein for a variety of uses in the laboratory because, like most abundant plasma proteins, it is very stable and soluble. Numerous carboxyl groups account for the net negative charge (pI 5.1) of BSA and its high solubility (compare to positively-charged, cationized BSA). In addition, the 67kDa protein is sufficiently large and complex to be fully immunogenic. Consequently, BSA is a popular carrier protein for conjugation to haptens and other weak antigens to make them more immunogenic for the purpose of antibody production. If not used to prepare the primary immunogen, BSA is a useful carrier protein to make antigens more amenable to analysis (e.g., screening assays involving plate coating) of antibodies that were produced using KLH or another more immunogenic carrier protein.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

Related Products
Imject™ Maleimide-Activated BSA

Imject™ Maleimide-Activated mcKLH (Thermo Scientific™)

Thermo Scientific Imject Maleimide-Activated mcKLH enables conjugation of sulfhydryl-containing peptide haptens to the highly immunogenic keyhole limpet hemocyanin (KLH) carrier protein for immunization and antibody production.

Features of Imject Maleimide-Activated mcKLH:

Optimized activation—specifications require that each lot is activated with more than 400 moles of sulhydryl-reactive maleimide per mole of KLH, ensuring consistently high levels of conjugation
Sulfhydryl-reactive—engineered for conjugating cysteine-containing peptide antigens to make effective immunogens for high-titer antibody production
Simple, rapid procedure—complete the hapten-carrier conjugation reaction in two hours to yield sufficient immunogen for several injections and booster immunizations of host animals
High-quality carrier protein—KLH is isolated from the mollusk Megathura crenulata (keyhole limpet); mcKLH is a high-quality form of KLH that is harvested from limpets grown in mariculture
Highly immunogenic—KLH has a high molecular mass (4.5 x 105 to 1.3 x 107 Daltons; aggregates of 350 and 390 kDa subunits) and elicits a stronger immune response than BSA or ovalbumin
Excellent solubility—our preparations of mariculture KLH are more soluble than typical forms

The high-quality mariculture KLH is rendered sulfhydryl-reactive by chemical modification with Sulfo-SMCC crosslinker, and the resulting maleimide-activated protein is then stabilized and lyophilized in phosphate buffer. Maleimide groups form covalent crosslinks with sulfhydryl (-SH) moieties on cysteine residues of peptides and other thiol-containing haptens. Numerous antigen molecules can be conjugated to each KLH molecule to make them highly immunogenic and increase the likelihood of eliciting immunized animals to produce high-titer antisera to the epitopes of interest. Select from among several package sizes of activated KLH protein, or choose the complete conjugation kit that includes optimized buffers and trouble-free spin desalting columns.

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether an adequate level of hapten-carrier conjugation can be achieved.

Keyhole limpet hemocyanin (KLH) is widely used as a carrier protein for conjugation to haptens and other antigens to make them more immunogenic for the purpose of antibody production. Because of its large mass and complexity, KLH elicits a stronger immune response than other carrier proteins. Because the protein is derived from a mollusk, it is phylogenetically distant from mammalian species and less likely to produce antibodies that will cross-react with typical target samples in assays.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

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Imject™ Maleimide-Activated mcKLH Spin Kit
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Imject™ cBSA (in PBS) (Thermo Scientific™)

Thermo Scientific Imject Cationized Bovine Serum Albumin (cBSA) functions as an easy-to-use and highly immunogenic carrier protein for preparing antigens for use in antibody production.

Imject cBSA is prepared by modifying native BSA with excess ethylenediamine, essentially capping all negatively-charged carboxyl groups with positively-charged primary amines. The result is a highly positively-charged protein (pI > 11) that has significantly increased immunogenicity compared to native BSA. In addition, the increased number of primary amines provides for a greater number of antigen molecules to be conjugated with typical crosslinking methods. Imject cBSA is an excellent choice for immunogen preparation when greater immunogenicity is needed relative to BSA but conditions are not amenable to using keyhole limpet hemocyanin (KLH) or Blue Carrier Protein.

Features of the Imject Cationized Bovine Serum Albumin:

• Purified bovine serum albumin (BSA) that is cationized and supplied lyophilized in PBS
• Single polypeptide protein with molecular mass > 67,000 Daltons
• Contains 59 lysine residues, plus numerous other primary amines added by cationization, most of which are capable of reacting with a conjugation reagent to attach antigens
• Net positive charge (pI >11), conferring solubility in conditions not suitable for the negatively-charged native BSA (pI 5.1)
• Significantly greater immunogenicity than native BSA because the positively charged protein is processed differently by the immune-response system (see references).

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate conjugation with the carrier can be achieved. Imject Cationized BSA (cBSA), which was previously called "SuperCarrier Protein" is very soluble in aqueous buffers and contains numerous primary amines that can be targeted for conjugation with glutaraldehyde, EDC, and other crosslinking reagents. For sulfhydryl-target conjugation (e.g., cysteine-containing peptide antigens), use Imject Maleimide-Activated cBSA.

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Imject™ EDC BSA Spin Kit (Thermo Scientific™)

The Thermo Scientific Imject EDC BSA Spin Kit is a package of purified bovine serum albumin carrier protein that enable simple preparation of effective immunogens with amine- or carboxyl-peptide antigens.

BSA is a popular immunogenic carrier protein used for preparation of peptide antigens for immunization and antibody production. Preparations in MES buffer are optimized for peptide-carrier conjugation via the carboxyl-reactive carbodiimide crosslinker called EDC (or EDAC). The Imject EDC Spin Kit includes ready-to-use units of BSA carrier protein, optimized reaction buffers and trouble-free spin desalting columns for immunogen preparation using the EDC method.

Features of the Imject EDC BSA Spin Kit:

Convenient kit—contains lyophilized BSA (in MES buffer), EDC crosslinker and accessories components to easily prepare ready-to-use immunogens for injection
High-yield conjugation—each molecule of 59 lysine residues, 30 to 35 of which have primary amines that are capable of reacting with a conjugation reagent
Validated quality—purified BSA (Fraction V) is ready for use in glutaraldehyde, NHS-ester or EDC crosslinking methods
Compatible solubility—numerous carboxyl groups account for the net negative charge (pI 5.1) of BSA and its high solubility, allowing its use in a broad range of conjugation conditions
Immunogenic—at 67 kDa, BSA is sufficiently large to function as the primary immunogen or it can be used as an irrelevant protein carrier for antibody screening and immunoassays after using KLH as the carrier protein to generate the immune response against the hapten

Carrier proteins are large, complex molecules capable of stimulating an immune response upon injection. Successful production of antibodies specific to small antigens (i.e., peptides or drug compounds) requires that these haptens be covalently conjugated to a larger, more complex molecule (usually a protein) to make them immunogenic. Carrier proteins are chosen based on immunogenicity, solubility, and whether adequate hapten-carrier conjugation can be achieved. Imject BSA is very soluble in aqueous buffers and contains numerous primary amines and carboxyl groups that can be targeted for conjugation with glutaraldehyde, NHS esters, EDC and other crosslinking reagents. Imject BSA is purified and lyophilized in buffers that optimize its stability and solubility for hapten conjugation.

Bovine serum albumin (BSA) is a convenient protein for a variety of uses in the laboratory because, like most abundant plasma proteins, it is very stable and soluble. In addition, the 67 kDa protein is sufficiently large and complex to be fully immunogenic. Consequently, BSA is a popular carrier protein for conjugation to haptens and other weak antigens to make them more immunogenic for the purpose of antibody production. It also provides an independent hapten-carrier protein for microplate and other assay techniques required to screen antibodies produced using KLH or another more immunogenic carrier.

The carbodiimide crosslinker EDC conjugates carboxyl-containing haptens (e.g., C-terminus of peptide antigens) to BSA carrier protein. This method of immunogen preparation is ideal for peptide antigens with few or no aspartic and glutamic acid residues (carboxylates) and lysine residues (primary amines) within the central portion of the primary sequence. Because peptides contain both carboxylate and amines, EDC conjugation results in their becoming variously polymerized and randomly oriented in their linkage to the carrier protein. Typically, this results in a high level of antigen loading on the carrier protein as well as presentation in all possible orientations for antibody production. However, important (desired) epitopes within the antigen peptide sequence may be blocked by EDC-mediated conjugation if those regions contain primary amines (lysine residues) or carboxylates (aspartic and glutamic acid residues). In these cases, either use a homobifunctional amine-reactive crosslinker with the purified BSA in phosphate buffer or synthesize the peptide with a unique terminal cysteine and use a kit with Malemide-Activated BSA to prepare the carrier protein conjugate.

More Product Data
Carrier protein activation and conjugation data for immunogen preparation

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Imject™ BSA (in PBS)
Imject™ BSA (in MES Buffer)