TGF-beta3 is a 25 kD polypeptide which exhibits potent biological effects on a variety of cell types. TGF-beta3 may be useful in cancer therapy, in wound healing indications and as an immunosuppressive agent. The goal of Phase I study was to express the TGF-beta3 cDNA. The investigators succeeded in establishing an initial expression system for TGF-beta3 and purified the corresponding protein to homogeneity. Furthermore, they prepared a series of both peptide polyclonal and monoclonal antibodies (MAbs) against different epitopes in TGF-beta3. Via their corporate collaboration with Pfizer, they now have a major pharmaceutical company interested in TGF-beta3 for multiple indications. However, it is apparent that commercial development is totally dependent upon establishing a cost effective production system. In Phase II study, they propose to increase the efficiency of expression of the recombinant protein produced in mammalian cells. Based on recent methodologies demonstrating successful expression of disulfide linked dimeric polypeptides in E. coli, they will also attempt to develop a procaryotic expression system to produce TGF-beta3 in E. coli.
