Search Thermo Fisher Scientific
Search Thermo Fisher Scientific
Gibco Heat Stable Recombinant Human Proteins have been engineered for greater stability in cell culture, exhibiting enhanced bioactivity at 37°C. Because Heat Stable proteins are bioactive longer than native proteins in standard cell culture conditions, researchers may be able to use less to maintain the same growth rates, therefore improving the efficiency of their cell culture applications.
Figure 1. Cell proliferation studies demonstrate Heat Stable FGFs exhibit superior activity compared to native FGFs. HS bFGF activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation (top panels). The 10 ng/mL HS bFGF (top left) and native bFGF (top right) solutions were stored at 4°C (unstressed) or 37°C (heat stressed) for 72 hours before being used to treat the Balb/3T3 cells in a dose-dependent manner. Likewise, HS FGF10 activity was measured with PrestoBlue HS Cell Viability reagent analysis of MCF7 cell proliferation (bottom panels). The 1 μg/mL HS FGF10 (bottom left) and native FGF10 (bottom right) solutions were stored at 4°C (unstressed) or 37°C (heat stressed) for 72 hours before being used to treat the MCF7 cells in a dose-dependent manner.
Figure 2. Heat Stable FGF growth factors demonstrate greater activity after 72 hours of heat stress than native proteins. (Left) HS bFGF activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation. (Right) HS FGF10 activity was measured with PrestoBlue HS Cell Viability reagent analysis of MCF7 cell proliferation. The percent activity is the amount of activity maintained after heat stress relative to the same solution stored at 4°C (unstressed). The 10 ng/mL HS bFGF and native bFGF, and 1 μg/mL HS FGF10 and native FGF10 solutions were stored at 4°C or 37°C for 72 hours before being used to treat Balb/3T3 or MCF7 cells, respectively.
Figure 3. Heat Stable FGFs allows normal proliferation of cells with growth factor. (A) 5 ng/mL of bFGF leads to significantly slower neural stem cell (NSC) proliferations as compared with 5 ng/mL HS bFGF, which maintains a proliferation rate equivalent to that of 20 ng/mL native bFGF. Mean +/- SEM. ** = p < 0.01. (B) Additionally, while 5 ng/mL native bFGF leads to neurite outgrowth (denoted by red arrows), HS bFGF maintains multipotent NSC morphology. (C) Relative activity of FGF10 was measured following incubation of 1 μg/mL HS FGF10 and native FGF10 stock solutions at 4°C or 37°C for 72 hours before being used to treat MCF7 cells. Activity measured with PrestoBlue HS Cell Viability reagent demonstrated 10 ng/mL of HS FGF10 performed equivalently to 100 ng/mL of native FGF10. Mean +/- SEM. *** = p < 0.0001; n.s. = not significant.
Figure 4. Heat Stable bFGF maintains the morphology and SOX1 expression of multipotent NSCs. Phase contrast (left) and immunostained (right) photomicrographs of NSCs cultured in the presence of HS bFGF (top row) and native bFGF (bottom row). Immunostaining for NSC multipotency marker SOX1 (red) with nuclear (DAPI) counterstain (blue).
Figure 5. Spontaneous differentiation supported by HS bFGF. Primary rat NSC isolated from Sprague Dawley E14 cortex cultured for 3 passages in DMEM/F12 + GlutaMAX supplemented with N2, NEAA, β-mercaptoethanol and 10 ng/mL HS bFGF. Media changes made every 48 hours without daily spiking of bFGF. At passage 3, cells were allowed to spontaneously differentiate by culturing in growth medium without HS bFGF. Cells showed equivalent potential to undergo undirected differentiation as compared to native bFGF, measured by markers MAP2 (neuron), GFAP (astrocytes) and GALC (oligodendrocytes).
Figure 6. HS bFGF enhances growth of cancer spheroids without the need for troublesome media changes. Spheroids were formed in Nunclon Sphera microplates in serum-free medium containing no bFGF, 10 ng/mL native bFGF, or 10 ng/mL HS bFGF. After 8 days in culture without media changes, the cells were stained via live (green)-dead (red) assay and DAPI counterstain (blue). All spheroids were viable, but the spheroid exposed to HS bFGF was the largest of the three experimental conditions. For more information please see our application note
Figure 7. bFGF-target and off-target gene expression was comparable in cells treated with native bFGF and Heat Stable bFGF. The TaqMan Array Human Signal Transduction Pathways array (Cat. No. 4418775) and the TaqMan Array Human FGF Pathway (Cat. No. 4414136) were used to assess expression of genes in the androgen, calcium, CREB, estrogen, hedgehog, insulin, JAK-STAT, LDL, mitogenic, NFAT, NFkB, p53, phospholipase C, protein kinase C, retinoic acid, stress, survival, TGF-β, Wnt, and FGF-associated pathways, respectively. Expression was assessed using human induced pluripotent stem cells treated with 10 ng/mL native bFGF or Heat Stable bFGF. Genes from both arrays were separated into ‘bFGF-target’ or ‘off-target’ based on their downstream relationship to bFGF, as is currently indicated by the literature. The bFGF-target and off-target panels show the results from 43 and 71 genes, respectively.
Figure 8. HS bFGF exhibits superior activity after extended 37°C incubation compared to competitor’s products. Activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation. The percent activity is amount of activity maintained after heat stress (37°C), relative to the same solution stored at 4°C (unstressed). The 10 ng/mL HS bFGF and competitor bFGF solutions were stored at 4°C or 37°C for 72 hours before being used to treat the Balb/3T3 cells, N≥3. Mean ± SEM.
Figure 9. Comparison iPSCs cultured in the presence of Gibco HS bFGF or StemBeads reagent. Microscopic images of StemBeads reagent (10 ng/mL) captured at (A) 10x and (B) 20x magnification. Because StemBeads beads vary in size (arrows indicate different sized StemBeads particles), they can be difficult to distinguish from cells and also from debris. Twenty-four hours after seeding human iPSCs in the presence of either (C) 10 ng/mL Gibco HS bFGF or (D) 10 ng/mL StemBeads reagent, phase-contrast images were captured of the cultured cells. The image of cells cultured with HS bFGF is clear, containing minimal debris, whereas the StemBeads reagent–containing culture shows more apparent debris. In addition because the beads tend to sink relatively quickly in solution, accurately measuring StemBeads reagent concentration can present a challenge.
Figure 1. Cell proliferation studies demonstrate Heat Stable FGFs exhibit superior activity compared to native FGFs. HS bFGF activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation (top panels). The 10 ng/mL HS bFGF (top left) and native bFGF (top right) solutions were stored at 4°C (unstressed) or 37°C (heat stressed) for 72 hours before being used to treat the Balb/3T3 cells in a dose-dependent manner. Likewise, HS FGF10 activity was measured with PrestoBlue HS Cell Viability reagent analysis of MCF7 cell proliferation (bottom panels). The 1 μg/mL HS FGF10 (bottom left) and native FGF10 (bottom right) solutions were stored at 4°C (unstressed) or 37°C (heat stressed) for 72 hours before being used to treat the MCF7 cells in a dose-dependent manner.
Figure 2. Heat Stable FGF growth factors demonstrate greater activity after 72 hours of heat stress than native proteins. (Left) HS bFGF activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation. (Right) HS FGF10 activity was measured with PrestoBlue HS Cell Viability reagent analysis of MCF7 cell proliferation. The percent activity is the amount of activity maintained after heat stress relative to the same solution stored at 4°C (unstressed). The 10 ng/mL HS bFGF and native bFGF, and 1 μg/mL HS FGF10 and native FGF10 solutions were stored at 4°C or 37°C for 72 hours before being used to treat Balb/3T3 or MCF7 cells, respectively.
Figure 3. Heat Stable FGFs allows normal proliferation of cells with growth factor. (A) 5 ng/mL of bFGF leads to significantly slower neural stem cell (NSC) proliferations as compared with 5 ng/mL HS bFGF, which maintains a proliferation rate equivalent to that of 20 ng/mL native bFGF. Mean +/- SEM. ** = p < 0.01. (B) Additionally, while 5 ng/mL native bFGF leads to neurite outgrowth (denoted by red arrows), HS bFGF maintains multipotent NSC morphology. (C) Relative activity of FGF10 was measured following incubation of 1 μg/mL HS FGF10 and native FGF10 stock solutions at 4°C or 37°C for 72 hours before being used to treat MCF7 cells. Activity measured with PrestoBlue HS Cell Viability reagent demonstrated 10 ng/mL of HS FGF10 performed equivalently to 100 ng/mL of native FGF10. Mean +/- SEM. *** = p < 0.0001; n.s. = not significant.
Figure 4. Heat Stable bFGF maintains the morphology and SOX1 expression of multipotent NSCs. Phase contrast (left) and immunostained (right) photomicrographs of NSCs cultured in the presence of HS bFGF (top row) and native bFGF (bottom row). Immunostaining for NSC multipotency marker SOX1 (red) with nuclear (DAPI) counterstain (blue).
Figure 5. Spontaneous differentiation supported by HS bFGF. Primary rat NSC isolated from Sprague Dawley E14 cortex cultured for 3 passages in DMEM/F12 + GlutaMAX supplemented with N2, NEAA, β-mercaptoethanol and 10 ng/mL HS bFGF. Media changes made every 48 hours without daily spiking of bFGF. At passage 3, cells were allowed to spontaneously differentiate by culturing in growth medium without HS bFGF. Cells showed equivalent potential to undergo undirected differentiation as compared to native bFGF, measured by markers MAP2 (neuron), GFAP (astrocytes) and GALC (oligodendrocytes).
Figure 6. HS bFGF enhances growth of cancer spheroids without the need for troublesome media changes. Spheroids were formed in Nunclon Sphera microplates in serum-free medium containing no bFGF, 10 ng/mL native bFGF, or 10 ng/mL HS bFGF. After 8 days in culture without media changes, the cells were stained via live (green)-dead (red) assay and DAPI counterstain (blue). All spheroids were viable, but the spheroid exposed to HS bFGF was the largest of the three experimental conditions. For more information please see our application note
Figure 7. bFGF-target and off-target gene expression was comparable in cells treated with native bFGF and Heat Stable bFGF. The TaqMan Array Human Signal Transduction Pathways array (Cat. No. 4418775) and the TaqMan Array Human FGF Pathway (Cat. No. 4414136) were used to assess expression of genes in the androgen, calcium, CREB, estrogen, hedgehog, insulin, JAK-STAT, LDL, mitogenic, NFAT, NFkB, p53, phospholipase C, protein kinase C, retinoic acid, stress, survival, TGF-β, Wnt, and FGF-associated pathways, respectively. Expression was assessed using human induced pluripotent stem cells treated with 10 ng/mL native bFGF or Heat Stable bFGF. Genes from both arrays were separated into ‘bFGF-target’ or ‘off-target’ based on their downstream relationship to bFGF, as is currently indicated by the literature. The bFGF-target and off-target panels show the results from 43 and 71 genes, respectively.
Figure 8. HS bFGF exhibits superior activity after extended 37°C incubation compared to competitor’s products. Activity was measured with PrestoBlue dye analysis of Balb/3T3 cell proliferation. The percent activity is amount of activity maintained after heat stress (37°C), relative to the same solution stored at 4°C (unstressed). The 10 ng/mL HS bFGF and competitor bFGF solutions were stored at 4°C or 37°C for 72 hours before being used to treat the Balb/3T3 cells, N≥3. Mean ± SEM.
Figure 9. Comparison iPSCs cultured in the presence of Gibco HS bFGF or StemBeads reagent. Microscopic images of StemBeads reagent (10 ng/mL) captured at (A) 10x and (B) 20x magnification. Because StemBeads beads vary in size (arrows indicate different sized StemBeads particles), they can be difficult to distinguish from cells and also from debris. Twenty-four hours after seeding human iPSCs in the presence of either (C) 10 ng/mL Gibco HS bFGF or (D) 10 ng/mL StemBeads reagent, phase-contrast images were captured of the cultured cells. The image of cells cultured with HS bFGF is clear, containing minimal debris, whereas the StemBeads reagent–containing culture shows more apparent debris. In addition because the beads tend to sink relatively quickly in solution, accurately measuring StemBeads reagent concentration can present a challenge.
Question | Answer |
---|---|
What are the possible abbreviations for basic fibroblast growth factor? | Basic fibroblast growth factor can be notated in the following ways: bFGF, FGF2, FGF-2, FGF-β, FGF-basic. |
What is heat stable? | Heat stable is the ability to sustain activity at elevated temperatures (37°C). Also known as thermostable. |
What kind of tubes should be used to store aliquots? | Polypropylene tubes should be used to store aliquots of reconstituted Heat Stable Recombinant Human bFGF. |
Does the His-tag on Heat Stable Recombinant Human bFGF affect biological activity? | No, the His-tag has no effect on biological activity. |
Is Heat Stable Recombinant Human bFGF full length? | Yes, Heat Stable Recombinant Human bFGF is full-length at 155 amino acids, plus 20 amino acids for N-terminal tag for purification purposes. |
How do I determine a working concentration? | We recommend that you use the same working concentration as native human bFGF that you are currently using. Cell cultures should be monitored to determine whether the working concentration can be reduced. |
Can Heat Stable Recombinant Human bFGF be used in place of native recombinant human bFGF? | Yes, Heat Stable Recombinant Human bFGF can be used in place of native human bFGF. It is a direct replacement, offering greater stability in cell culture conditions. |
Was any additive added to achieve thermostability of Heat Stable Recombinant Human bFGF? | No additives were used. Heat Stable Recombinant Human bFGF was engineered to maintain bioactivity at 37°C. The patent pending technology has >90% sequence homology to native human bFGF. |
Has protein engineering altered the activity of Heat Stable Recombinant Human bFGF? | HS bFGF does not exhibit higher bioactivity, nor does it stimulate cell signaling differently than native bFGF. |
Why should Heat Stable Recombinant Human bFGF be used instead of native recombinant human bFGF? | Native human bFGF degrades at standard culture conditions (i.e., 37°C). This means that more frequent media changes and/or more protein is required to maintain biological activity. Heat Stable Recombinant Human bFGF retains bioactivity minimizing fluctuations to more closely mimic physiological conditions for cells. |
How long can I use media supplemented with Heat Stable Recombinant Human bFGF? | We recommend that you use growth factor-supplemented medium within 2-4 weeks of supplementation. |
Can I freeze aliquots after reconstitution? | Yes, aliquots can be frozen and stored at -20°C for up to 1 year from date of receipt. Avoid additional freeze/thaw cycles. |
I am not able to resuspend the 5 µg size at the recommended concentration. How should I use it? | The 5 µg Heat Stable Recombinant Human bFGF should be reconstituted directly in the intended culture medium, preferably media containing BSA or similar protein. |
For Research Use Only. Not for use in diagnostic procedures.