CO-FACTORS FOR TROPHIC FACTORS, AND METHODS OF USE THEREOF

摘要

The present invention is based on the discovery and isolation of a co-factor for trophic factors. It has been discovered that trophic factors require a co-factor to stimulate and/or potentiate the trophic factor activity and/or specificity. This was clearly identified in low density cells where trophic factors are unable, or at best, at minimal levels, able to proliferate undifferentiated cells without a co-factor. In a particular embodiment of the present invention, there is provided a composition comprising glycosylated cystatin C (CCg), an FGF co-factor that stimulates proliferation of neural and fibroblast associated undifferentiated cells. The N-glycosylation of cystatin C is required for its activity. Moreover, CCg acts in cooperation with basic fibroblast growth factor (FGF-2) to induce neural progenitor cell proliferation.