Human-porcine MHC-I homology allows for antibody cross-reactivity

Pigs are especially useful large animal models, however, limited availability of commercially available antibodies for immunoblotting presents a significant obstacle facing preclinical xenotransplantation research. Major histocompatibility complex class I (MHC-I) molecule expression enhancement by nucleotide-binding oligomerization domain (NOD)-like receptor family with a caspase recruitment domain (CARD) containing caspase 5 (NLRC5) is fundamental to understanding porcine xenoantigen presentation. Swine Leukocyte Antigens (SLAs) are the porcine MHC homologs for human leukocyte antigens. SLA-I is a known xenoantigen that causes T cell activation. NLRC5, SLA-I, and B2M are all targets of immune modulation in genetically engineered pigs in xenotransplantation research with the goal to reduce SLA-I expression. In the present study, the human anti-NLRC5 (ab105411), anti-NLRC5 (ab117624), anti-NLRC5 N-terminal (ab178767), anti-HLA E (ab203082), anti-HLA E (ab135826), anti-HLA E (ab2216) and anti-β₂ M (ab75853) antibodies were examined using immunoblots for porcine cross-reactivity. The anti-human antibodies ab117624, ab105411, ab178767, ab2216, and ab75853 cross reacted with cognate proteins in porcine cell lysates. Antibody reagents from this study will allow for validation of NLRC5, B2M, MHC-I expression in future research studies. In addition, following the methodology described in this study for other xenotransplantation targets may provide an alternative to custom antibody development.

Functional analysis of prv-miR-LLT11a encoded by pseudorabies virus

Viral-encoded microRNAs (miRNAs) have vital roles in the regulation of virus replications and host immune responses. The results of previous studies have indicated that miRNA clusters are involved in the replication and virulence of the pseudorabies virus (PRV), which may potentially lead to immune escape or facilitation of PRV replication. This study's previous research revealed that prv-miR-LLT11a was differentially expressed during PRV infection. The present study's results have demonstrated that prv-miR-LLT11a could significantly inhibit PRV replication. It was further determined that SLA-1 was the target gene of prv-miR-LLT11a, and simultaneously, that overexpression of prv-miR-LLT11a could downregulate the mRNA and protein levels of SLA-1 in a dose-independent manner. Furthermore, the present study also observed that prv-miR-LLT11a can downregulate TAP1 expression. Our findings provide a better understanding of the molecular mechanism involved in the effects of prv-miR-LLT11a on SLA-1 and TAP1 as well as its involvement in immune system evasion of PRV.