MONOCLONAL ANTIBODIES REACTIVE WITH SWINE LYMPHOCYTES I. Antibodies to Membrane Structures That Define the Cytolytic T Lymphocyte Subset in the Swine1

A panel of monoclonal antibodies (mAb) with spec-ificity for swine leukocytes was prepared by somatic cell hybridization with the use of spleen cells from mice immunized with swine thymocytes. The reac-tivity of two mAb (295/33 and 122/28). which both immunoprecipitated from the surface of swine leu-kocytes an antigen termed 5-L2 with an apparent m.w. of 33 to 35 kilodaltons under reducing and 65 to 70 kilodaltons under nonreducing conditions. was investigated in detail. These mAb were reactive in indirect immunofluorescence with 50 to 60 % of thymocytes. 35 % of peripheral blood lymphocytes. and 55 % of E rosette-positive cells; they were non-reactive with bone marrow cells. Ig+ B cells. nonro-setting lymphocytes. granulocytes. and monocytes