Thermostable FGF Basic / FGF2 (FGFbasic-TS) for stem cell (hESC or iPS) culture

Thermostable FGF Basic / FGF2 (FGFbasic-TS) for stem cell (hESC or iPS) culture

FGFbasic stem cell

FGF basic (also known as FGF-2 or bFGF) is required in stem cell cultures to maintain the stem cells in an undifferentiated and pluripotent state. However, FGF basic is unstable, requiring daily media changes with fresh addition of FGF basic, which is costly, tedious and time consuming. To overcome this problem, a thermal stable version of FGF basic (FGFbasic-TS) has been developed to support a 2-day media change protocol instead of daily media change. The 2-day media change protocol relieves stem cell researchers from coming back to the lab over the weekend , making it an ideal choice for stem cell researchers.

Thermostable FGF basic (FGFbasic-TS) was carefully engineered for enhanced stability in culture media, without affecting its biological functions. The 154 amino acid, 17 kDa, non-glycosylated monomer cytokine is expressed with our HumanKine™ technology developed for production of authentic human recombinant proteins.

Stability of thermostable FGF basic (FGFbasic-TS) in cell culture media

When cultured in a typical stem cell culture media at 37°C, a considerable amount (35%) of Thermostable FGF basic (FGFbasic-TS, SKU# SDP1025) remains intact in the media after 2 days of culture, while regular FGF basic (SKU# YCP1143) is undetectable after day 1. The results suggest thermostable FGF basic degrades roughly 3 times more slowly than regular FGF basic.

FGFbasic-TS stability

Resistance of thermostable FGF basic (FGFbasic-TS) to enzymatic digest

When exposed to trypsin, FGF basic is significantly degraded after 4.5 hours, while FGFbasic-TS levels are only slightly reduced. Of note, Heprin protects FGF2 and FGFbasic-TS from trypsin digestion. Thermostable FGF basic is more resistant towards proteolytic degradation compared to FGF basic.

FGFbasic-TS degradation

Thermostable FGF basic (FGFbasic-TS) maintains pluripotency of stem cells with 2-day feeding schedule

Using a two day feeding protocol, pluripotency of stem cells is effectively maintained after 10 passages, regardless that the cells are human embryonic stem cells (hESC) or induced pluripotent stem cells (iPSC); passaged using a non-enzymatic passaging solution (XFPS) or using a collagen-based reagent (CG); cultured in chemically defined matrix (XFM) or in Matrigel (MG). Pluripotency is confirmed by cytometric analysis of stem cell markers including SSEA-4, Tra1-60, Tra1-81 and Oct3/4.

FGFbasic-TS culture

Thermostable FGF basic (FGFbasic-TS) maintains FGF basic’s activity in promotion of stem cell proliferation

With a two day feeding protocol, iPSC cell cultures maintained healthy growth characteristics even after 10 passages. The picture below shows iPS cells at the 2nd and 6th day of culture, respectively.

FGFbasic-TS morphology

Thermostable FGF basic (FGFbasic-TS) does not induce genetic abnormalities

Stem cell cultures are known to develop genetic abnormalities during long-term culture. On a 2-day feeding schedule with 10 mg/mL FGFbasic-TS, an iPS cell line remains normal in karyotype analysis after the 10th passage.

FGFbasic-TS karyotype