Blocking of cytotoxic T-cell function of MOLF/Ei mice by anti-Ly 35.1 monoclonal antibody

Ly 35.1 antigen is an alloantigen expressed only on T cells of Mus musculus molossinus-derived inbred strains. Previous findings indicated that the genetic locus coding for Ly 35 antigen was closely linked to Ly 2/3 on chromosome 6 and that epitopes detected by Ly 2.1 and Ly 35.1 monoclonal antibodies (mAb) were closely associated, as shown by binding inhibition assay. In this study, we examined the blocking effects of anti-Ly 2.1 and anti-Ly 35.1 mAb on cytotoxic T-cell function of MOLF/Ei mice generated against BALB/c. MOLF/Ei cytotoxicity was blocked by Ly 35.1 mAb, but not by anti-Ly 2.1 mAb. Additional tests showed that cytotoxicity was blocked by Ly 3.1 mAb, but not Ly 3.2 or Ly 2.2 mAb. These results suggested that MOLF/Ei mice express Ly 3.1, but not Ly 2.1 antigen at a functional level, and that Ly 35.1 may be a functional epitope of Ly 2 antigen in the MOLF/Ei strain.