Properties of human transfer factor from KLH immunized donors: dissociation of dermal transfer and proliferation augmenting activities

Human transfer factor (TF) contains many biologic activities including the ability to transfer dermal reactivity and the ability to augment lymphocyte proliferation in vitro. The dermal transfer component for keyhole limpet hemocyanin is only apparent following immunization to that Ag. This component of TF elutes from Sephadex G-25 in a discrete region (3a) and has an isoelectric point of 1.6. It elutes from high pressure reverse phase chromatography (HPRP) in two regions (R-2 and R-4) before alkaline phosphatase treatment, but in only one region (R-1) after alkaline phosphatase treatment. This component was found to be pronase sensitive. The component in TF which augments lymphocyte proliferation is found in both immune and nonimmune donors, but can only augment cells from immune recipients. It elutes from Sephadex G-25 in both Fractions 3a and 3b and has low retention time on HRPR (R-1). It is pronase resistant, but is sensitive to alkaline phosphatase treatment. These data suggest that the components responsible for dermal transfer activity and augmentation of lymphocyte proliferation are chemically distinct.