Immunologic specificity of transfer factor.

This study examined the immunologic specificity of transfer factor using a chromatographically purified transfer factor preparation. The specificity of transfer was examined utilizing immunity to keyhole limpet hemocyanin (KLH) and tuberculin. Transfer factor prepared from a donor immune to KLH successfully transferred KLH skin test reactivity to 10 out of 10 recipients. In contrast, comparable amounts of transfer factor from two donors not immune to KLH failed to transfer immunity to KLH in 11 recipients despite evidence for successful transfer of tuberculin reactivity. Unlike prior studies with a variety of antigens, the immunity to KLH in recipients of KLH immune transfer factor appeared comparable to that of the donor since both could be elicited with the same skin test antigen dose. These observations indicate that transfer factor can initiate a specific immune response to an antigen not previously encountered by the recipient and that in certain circumstances this immune response can be comparable to that of the donor. These observations on specificity and potency of transfer factor have important implications for the clinical use of this material.