Using SLA inbred and recombinant miniature swine as models, this dissertation describes: (1) Quantitative differences in GLO enzyme activity associated with the SLA complex; (2) The mapping of swine C2, Bf, and C4 genes to the SLA complex; and (3) The preparation and characterization of MAb to swine leukocyte antigens. In the first project, no electrophoretic differences in GLO among miniature swine were detected. However, GLO enzyme activity in SLA[superscript] a/a cells was consistently higher than in SLA[superscript] d/d cells, whereas GLO activity of SLA[superscript] a/d heterozygotes was intermediate. Using this information, a family study was conducted which suggested linkage of the Glo gene to the SLA complex. In the second project, C2, Bf, and C4 restriction fragments were detected in miniature swine by Southern blot hybridization with human cDNA probes. DNA polymorphisms were indentified in the Bf (TaqI and MspI RFLPs) and the C4 (BamHI, PvuII, and SstI RFLPs) loci. The detection of restriction fragments common to the C2 and Bf probes suggested that there is a close linkage of the swine C2 and Bf genes. The segregation of Bf and C4 DNA polymorphisms with SLA class II genes in the recombinant SLA[superscript] g, suggested that Bf and C4 genes are linked to the class II genes in miniature swine. In the third project, a panel of murine MAb were produced against swine peripheral mononuclear cells. The cell binding activity of 20 MAb was determined by ELISA and indirect immunofluorescence assays. None of the MAb were haplotype specific. The mononuclear weights of the antigens recognized by six of the MAb were determined by immunoprecipitation and SDS-PAGE. The most interesting MAb, 7-34-1 (IgG2a), precipitated a putative MHC class I molecule composed of a 50 kd heavy chain and a 12 kd light chain ([beta][subscript]2m). This MAb did not bind radiolabeled swine [beta][subscript]2m and was not inhibited by the presence of free [beta][subscript]2m. These data indicate that the antigenic determinant recognized by 7-34-1 is probably on the heavy chain of the SLA class I molecule. Properties of MAb 7-34-1 are different from the two known SLA class I specific MAb, 74-11-10 and PT85. MAb 7-34-1 should be especially useful as a general anti-SLA class I reagent.