Baseline Characterization of Swine Leukocyte Antigen Diversity in GFP-Expressing Domestic Swine

Yorkshire piglets serve as valuable animal models in biomedical research, including partial heart transplantation research. This study characterizes the swine leukocyte antigen (SLA) diversity within a cohort of 16 Yorkshire piglets, including 5 genetically modified to express green fluorescent protein (GFP). Employing SLA typing, we identified 25 unique SLA class I alleles (9 SLA-1, 11 SLA-2, 5 SLA-3) and 17 unique SLA class II alleles (8 DRB1, 6 DQB1, 3 DQA). Notably, an allele of SLA-1*08:XX was detected in 75% of the piglets, while haplotypes Lr-7.26 and Lr-6.12b were most frequent, occurring at 18.75%. Comparative analysis with previous studies revealed consistent genetic trends, although differences in haplotype frequencies underscore the influence of breeding practices and sample size on SLA allele and haplotype distribution. Our findings highlight the significant polymorphism in the SLA complex of Yorkshire piglets, which is relevant for their utility as preclinical models for studying transplantation outcomes. The characterization of GFP piglets provides crucial genomic data for future research in cell tracking and graft integration. While the study's relatively small cohort may limit its generalizability, it represents the first baseline SLA typing of GFP Yorkshire piglets, offering foundational insights into their genetic diversity. This work emphasizes the importance of standardized genetic mapping to enhance the reproducibility and utility of laboratory swine in biomedical research.