Basic fibroblast growth factor supports undifferentiated human embryonic stem cell growth without conditioned medium

Area of Science:

• Stem Cell Biology
• Developmental Biology
• Biotechnology

Background:

• Prolonged propagation of undifferentiated human embryonic stem cells (hESCs) traditionally requires conditioned medium from mouse embryonic feeders (MEF-CM).
• hESCs express receptors for key growth factors like basic fibroblast growth factor (bFGF), stem cell factor (SCF), and fetal liver tyrosine kinase-3 ligand (Flt3L).

Purpose of the Study:

• To evaluate the efficacy of specific growth factors in maintaining undifferentiated hESCs without MEF-CM.
• To identify growth factor combinations that support hESC pluripotency and stability.

Main Methods:

• hESCs were cultured in various defined media supplemented with specific growth factors, replacing MEF-CM.
• Cultures were assessed for morphology, surface marker and transcription factor expression, telomerase activity, differentiation potential, and karyotypic stability over 6 weeks.

Main Results:

• Cultures maintained with bFGF, alone or in combination with other factors, exhibited characteristics comparable to MEF-CM controls.
• Cultures supplemented with Flt3L, thrombopoietin, and SCF led to near-complete differentiation within 6 weeks.

Conclusions:

• hESCs can be successfully maintained in an undifferentiated state using defined media supplemented with specific growth factors, eliminating the need for MEF-CM.
• Basic fibroblast growth factor (bFGF) is a key factor in supporting hESC self-renewal and stability in feeder-free conditions.