Citations & References

Flow cytometry detection of surface antigens on fresh, unfixed red blood cells infected by Plasmodium falciparum.

  • Authors: Jouin H, Goguet de la Salmonière YO, Behr C, Huyin Qan Dat M, Michel JC, Sarthou JL, Pereira da Silva L, Dubois P
  • Journal: J Immunol Methods (1995) 179:1-12
  • PubMed ID: 7868917

Product FAQ

What is BVD virus (BVDV) in fetal bovine serum and how does it apply to cell culture applications?

Answer

BVD stands for Bovine Viral Diarrhea. It is one of the most common viral infections in cattle. It is estimated that 70 to 90 percent of the world's cattle population is seropositive for BVD. This virus can cause abnormalities and fetal abortions in cattle. Several strains of BVD exist, some of which are non-pathogenic.

Bovine serum is tested in accordance with 9 CFR, Section 113.53. The BVDV fluorescent antibody test is one of the required tests to meet Title 9 part 113.53 of the Code of Federal Regulations. However, the results of this test are somewhat subjective in the way they are scored. They are scored 0 to +4, based on the level of observed fluorescence. Most samples will have a detectable level of BVDV antigen due to its prevalence in the bovine population. The FA part of the testing can reveal the presence of non-cytopathic BVD strains. The Cytopathogenic and Hemadsorbing Agents testing is used to determine the release of bovine serum, regardless of the BVDV result. We currently report the BVDV results as “Tested”. Any live cytopathic bovine viruses (including the cytopathic BVDV strain) would be revealed in the testing for cytopathogenic agents. In this portion of the testing, the cultures are microscopically monitored for evidence of inclusion bodies, abnormal number of giant cells, or other cytopathology indicative of cell abnormalities. The hemadsorption assay detects the presence of hemagglutinating viruses. The viral hemagglutinin would induce clumping of red blood cells. If a positive result in the cytopathogenic agents or hemadsorbing agents assays is reported, the material would be failed and therefore would not be released by Quality Assurance.

Answer Id: E11874

Was this answer helpful?

Yes
No
Thank you for your response

Product FAQ

Does the Total Exosome Isolation reagent for serum work on plasma samples?

Answer

Plasma is a more challenging type of sample compared to serum. It has rather high levels of clotting factors. The current serum reagent will work on plasma, and it will precipitate all exosomes. However, the preparation will have some contaminating proteins and microvesicles, which will work for some projects, but not be acceptable for others. We recommend using our specifically optimized kits for recovery of exosomes from blood plasma (Cat. No. 4484450), as well as urine (Cat. No. 4484452), or other body fluids (Cat. No. 4484453).

Answer Id: E7391

Was this answer helpful?

Yes
No
Thank you for your response

Product FAQ

What is the difference between serum and plasma?

Answer

Plasma is the liquid portion of the blood that is separated from the blood cells by centrifugation. One of the characteristics of plasma is that it clots easily, which is important for hemophiliacs needing a transfusion but is a nuisance in most other applications. By agitating the plasma, one can precipitate the clotting factors as a large clot, and the leftover fluid is called serum. In other words, serum plus clotting factors is plasma, and clotted plasma yields serum.

Answer Id: E5234

Was this answer helpful?

Yes
No
Thank you for your response

Product FAQ

How does one prepare serum and plasma samples?

Answer

Serum is the liquid fraction of whole blood that is collected after the blood is allowed to clot. The clot is removed by centrifugation and the resulting supernatant, designated serum, is carefully removed using a Pasteur pipette. Plasma is produced when whole blood is collected in tubes that are treated with an anti-coagulant. The blood does not clot in the plasma tube. The cells are removed by centrifugation. The supernatant, designated plasma, is carefully removed from the cell pellet using a Pasteur pipette.

Serum preparation: Collect whole blood in a covered test tube. If commercially available tubes are to be used, the researcher should use the red topped tubes. These are Becton Dickinson Vacutainer tubes. After collection of the whole blood, allow the blood to clot by leaving it undisturbed at room temperature. This usually takes 15-30 minutes. Remove the clot by centrifuging at 1,000-2,000 x g for 10 minutes in a refrigerated centrifuge. The resulting supernatant is designated serum. Following centrifugation, it is important to immediately transfer the liquid component (=serum) into a clean polypropylene tube using a Pasteur pipette. The samples should be maintained at 2-8°C while handling. If the serum is not analyzed immediately, the serum should be apportioned into 0.5 mL aliquots and stored and transported at -20°C or lower. It is important to avoid freeze/thaw cycles because this is detrimental to many serum components. Samples which are hemolyzed, icteric, or lipemic can invalidate certain tests.

Plasma preparation: Collect whole blood into commercially available anti-coagulant treated tube, such as EDTA treated (lavender tops) or citrate treated (light blue tops). Heparinized tubes (green tops) are indicted for some applications; however, heparin can often be contaminated with endotoxin and endotoxin can stimulate white blood cells to release cytokines. Cells are removed from plasma by centrifugation for 10 minutes at 1,000-2,000 x g using a refrigerated centrifuge. Centrifugation for 15 minutes at 2,000 x g depletes platelets in the plasma sample. The resulting supernatant is designated plasma. Following centrifugation, it is important to immediately transfer the liquid component (=plasma) into a clean polypropylene tube using a Pasteur pipette. The samples should be maintained at 2-8°C while handling. If the plasma is not analyzed immediately, the plasma should be apportioned into 0.5 mL aliquots and stored and transported at -20°C, or lower. It is important to avoid freeze/thaw cycles. Samples which are hemolyzed, icteric, or lipemic can invalidate certain tests.

There are other commercially available tubes for blood sample collection. Thermo Fisher Scientific has not evaluated some of these tubes for compatibility with our ELISA kits. The commercially available serum tubes are as follows:Red: No anticoagulant. Red with black: treated with gel to help to separate the clot (not evaluated). The commercially available plasma tubes are as follows: Lavender: Treated with EDTA. Blue: Treated with citrate. Green: Treated with heparin. Grey: Treated with potassium oxalate/sodium fluoride (not evaluated). Yellow: Treated with ACD (not evaluated).

References: 1. Henry, J.B. (1979) Clinical Diagnosis and Management by Laboratory Methods, Volume 1, W.B Saunders Company, Philadelphia, PA, p. 60. 2. Thavasu, P.W., S. Longhurst, S.P. Joel, M.L. Slevin, and F.R. Balkwill (1992) Measuring cytokine levels in blood. Importance of anticoagulants, processing, and storage conditions. J. Immunol. Methods 153:115-124.

Answer Id: E5129

Was this answer helpful?

Yes
No
Thank you for your response

Product FAQ

What are general guidelines for the production of blood serum and plasma for cytokine analysis using ELISA and ProcartaPlex assays?

Answer

Serum is the liquid fraction of whole blood that is collected after the blood has clotted. The clot is removed by centrifugation and the resulting supernatant is the serum. It is carefully removed and used right away or it can be stored at -20 degrees C or below. Plasma is produced when whole blood is collected in tubes that contain an anticoagulant. In this case, the blood does not clot and the red and white blood cells are removed by centrifugation. The supernatant, called plasma, is carefully removed from the cell pellet and can be used right away or stored frozen for testing later.

Here are some procedures for preparing serum and plasma:

For serum, collect whole blood in capped test tubes and allow it to clot. Typically, commercially available tubes such as Vacutainer tubes are used, and for serum, the researcher should use the ones with red tops (no anticoagulant added). Vacutainer tubes of various types and volumes are available from Fisher Scientific. After collecting the blood, leave it undisturbed at room temperature to clot, which usually takes 15-30 minutes. Remove the clot by centrifugation at 1,000-2,000 x g for 10 minutes in a refrigerated centrifuge. The resulting supernatant is the serum. Following centrifugation, it is important to immediately transfer the sera into clean polypropylene tubes. These samples should be kept on wet ice until they are used or frozen. If the sera are not analyzed immediately, they should be divided into 0.5 mL aliquots and stored frozen at -20 degrees C or lower. It is important to avoid freeze/thaw cycles because this is detrimental to many serum components. Also, serum derived from blood that has undergone hemolysis (erythrocyte lysis), is icteric (contains bilirubin) or is lipemic (contains lipids) can invalidate certain tests.

For plasma preparation, collect whole blood into commercially available anticoagulant-treated Vacutainer or equivalent tubes. Tubes that are EDTA-treated (lavender tops) or citrate-treated (light blue tops) are commonly used. Heparinized tubes (green tops) are indicated for some applications. However, heparin can be contaminated with endotoxin, which can stimulate white blood cells to release cytokines. Cells are removed from the non-coagulated blood by centrifugation for 10 min at 1,000-2,000 x g using a refrigerated centrifuge. Centrifugation for 15 min at 2,000 x g depletes platelets in the plasma sample, if desired. Either way, the resulting supernatant is the plasma. Following centrifugation, it is important to immediately transfer the plasma into clean polypropylene tubes. The samples should be maintained on wet ice during handling. If the plasma is not analyzed immediately, it should be divided into 0.5 mL aliquots and stored at –20 degrees C or lower. It is important to avoid freeze/thaw cycles with plasma as well. Like serum, plasma derived from hemolyzed, icteric, or lipemic blood can invalidate certain tests.

Besides Vacutainer tubes, there are other commercially available tubes for blood sample collection. However, we have not evaluated these tubes to see if sera and plasma samples derived with them are compatible with our ELISA and ProcartaPlex kits. Nevertheless, commercially available blood collection tubes for serum are designated as follows: red caps = no anticoagulant or red caps with black stripes = no anticoagulant and containing gel to help to separate the clot (not evaluated). Blood collection tubes for plasma are as designated as follows: lavender cap = treated with EDTA, blue cap = treated with citrate, green cap = treated with heparin, grey cap = treated with potassium oxalate/sodium fluoride (not evaluated), and yellow cap = treated with acid-citrate-dextrose (not evaluated).

Answer Id: E5220

Was this answer helpful?

Yes
No
Thank you for your response

Citations & References

In vitro cellular adaptations of indicators of longevity in response to treatment with serum collected from humans on calorie restricted diets.

  • Authors: Allard JS, Heilbronn LK, Smith C, Hunt ND, Ingram DK, Ravussin E, de Cabo R
  • PubMed ID: 18791640
Catalog #

Citations & References

Prevalence of GB virus C (also called hepatitis G virus) markers in Norwegian blood donors.

  • Authors: Nordbo SA; Krokstad S; Winge P; Skjeldestad FE; Dalen AB
  • Journal: Journal of Clinical Microbiology 2000 7:2584-2590
Catalog #
  • 4318739(Discontinued)
  • 4327058(Discontinued)
  • 4327059(Discontinued)

Manual / Product Insert

ChargeSwitch gDNA 1 ml Blood Kit

Version: Version B 2/14/05
Catalog #
  • CS11001(Discontinued)

Manual / Product Insert

H-12000 Blood Processing Swinging Bucket Rotor Instruction Manual [EN]

Version: NOV.2016
Catalog #

Product Literature

Rapid, Single-Spin Fractionation of Serum Lipoproteins by Density Gradient Ultracentrifugation in Vertical Rotors

Product Literature

Specialty and Serum-Free Media

Product Literature

Serum-Free Cell Culture