Cellular immunity in gnotobiotic primates induced by transfer factor.

Abstract Human dialyzable transfer factor (TF) was found capable of inducing in vivo (skin test) and in vitro blastogenesis) cellular immunity in gnotobiotic nonhuman primates. Because the animals were gnotobiotic (germ-free) and had not been skin tested previously, these data support the hypothesis that induction of cell-mediated immunity in recipients of TF does not require a “priming” exposure to specific and/or cross-reacting antigens, and that this induction may be due to an antigen-specific informational effect of TF. In addition, these results support the antigenic specificity of TF, in that recipient primates developed cellular reactivity only against donor “positive” but not against donor “negative” antigens.