Transfer Factor from BCG-Sensitized Mice

A mouse model was established for the study of transfer factor (TF). TF was extracted from the spleens of sensitized mice and examined for activity by the footpad test, which showed that mouse and human TF possessed similar properties. Parenteral administration of TF imparted to unsensitized mice immunologically specific, delayed type hypersenstivity within 24 hr. The magnitude of the response the recipients showed was proportional to the dose of TF. TF activity was relatively heat-stable, detectable in a fraction of molecular weight of ca 1,000 and apparently contained nucleic acids. Nude mice responded negatively to TF but following administration of viable naive spleen cells a positive response was observed, which suggests that the thymus plays an important role in the expression of TF phenomenon and that the target of TF is the T cells.