Antigen-specific augmentation factor involved in murine delayed-type footpad reaction.III.Genetic restriction of delayed hypersensitivity augmentation factor (DAF)

We found an antigen-specific factor capable of augmenting delayed-type hypersensitivity (DTH) in the culture supernatant of the mixture of immune T cells and specific antigen, or in the serum of mice immunized with xenogeneic erythrocytes and elicited for DTH footpad reaction.Previous experiments on the genetic restriction of this factor (DTH-augmentation factor; DAF) indicated that DAF activity was effective across the MHC-barrier in OH/He (H-2^k) - BALB/c (H-2^d) system.The genetic restriction between DAF and its acceptor cells was then investigated precisely using Igh (immunoglobulin heavy chain locus)-congeneic mice: 1) Expression of DAF activity was MHC-nonrestricted, 2) but was restricted by the Ighlinked gene on the 12th chromosome, 3) such Igh-linked gene restriction was also demonstrated by an absorption test with normal spleen cells.The acceptor cells for DAF were Thy-1⁺, L3T4⁺, Lyt-2⁻ T cells.