| Abstract: | Human leukocyte dialysates contain components capable of amplifying cutaneous delayed-type hypersensitivity (DTH) reactions. In the present study, two such amplifiers, both less than 3500 m.w., were partially purified from human leukocyte dialysates by gel filtration on Sephadex G-10 followed by high pressure reverse-phase liquid chromatography. These amplifiers of DTH were examined for their effects on production of the migration inhibitory lymphokines leukocyte migration inhibition factor (LIF) and macrophage migration inhibition factor (MIF). The amplifiers were found to increase LIF and MIF production by antigen- or alloantigen-stimulated human peripheral blood lymphocytes in a dose-dependent fashion. Further analysis demonstrated that although antigen-stimulated T4 and T8 cell subpopulations could produce LIF activity under the assay conditions employed, amplification of lymphokine production by modulator was only observed with the T4 subset. |
