Inhibition of antigen-induced T-cell proliferation by antibodies to endogenous AKR-MuLV

Lymph node cells from BALB/c mice immunized with ovalbumin or human γ-globulin were restimulated in vitro with these antigens and assayed for antigen-induced proliferation. The proliferative response was shown to be antigen specific and T cell dependent. A rabbit antiserum to envelope and core proteins of AKR murine leukemia virus was found to inhibit antigen-induced T-cell proliferation. The IgG fraction and F(ab′)₂ fragments of the antiserum were also inhibitory. The inhibition occurred after the initial step of antigen-T cell interaction and viral absorption studies showed the inhibition to be specific for anti-AKR virus antibodies. A hypothesis for the mechanism of inhibition is discussed in relation to a functional role for endogenous murine leukemia virus.