N-glycolylneuraminic acid knockout reduces erythrocyte sequestration and thromboxane elaboration in an ex vivo pig-to-human xenoperfusion model.

Background: Wild-type pigs express several carbohydrate moieties on their cell surfaces that differ from those expressed by humans. This difference in profile leads to pig tissue cell recognition of human blood cells causing sequestration, in addition to antibody-mediated xenograft injury. One such carbohydrate is N-glycolylneuraminic acid (Neu5Gc), a sialic acid molecule synthesized in pigs but not in humans.

Adiponectin: Its role in obesity-associated colon and prostate cancers.

Adipose tissue synthesizes many proteins and hormones collectively called adipokines, which are linked to a number of diseases, including cancer. Low levels of adiponectin are reported to be a risk factor for obesity-related cancers including colorectal and prostate cancers. Accordingly, obesity/lifestyle-related diseases, including certain cancers, may be treated by developing drugs that act specifically on adiponectin levels in circulation.

Human antibody recognition of xenogeneic antigens (NeuGc and Gal) on porcine heart valves: could genetically modified pig heart valves reduce structural valve deterioration?

Background: Glutaraldehyde-fixed bioprosthetic heart valves (GBHVs) derived from wild-type (WT, genetically unmodified) pigs are widely used clinically for heart valve replacement. There is evidence that their failure is related to an immune response. The use of valves from genetically engineered pigs that do not express specific pig antigens may prolong GBHV survival.

Initial in vitro studies on tissues and cells from GTKO/CD46/NeuGcKO pigs.

Background: The impact that the absence of expression of NeuGc in pigs might have on pig organ or cell transplantation in humans has been studied in vitro, but only using red blood cells (pRBCs) and peripheral blood mononuclear cells (pPBMCs) as the target cells for immune assays. We have extended this work in various in vitro models and now report our initial results.

Methods: The models we have used involve GTKO/hCD46 and GTKO/hCD46/NeuGcKO pig aortas and corneas, and pRBCs, pPBMCs, aortic endothelial cells (pAECs), corneal endothelial cells (pCECs), and isolated pancreatic islets.

B-Cell-Deficient and CD8 T-Cell-Depleted Gnotobiotic Pigs for the Study of Human Rotavirus Vaccine-Induced Protective Immune Responses.

Genetically modified pigs have become available recently. In this study, we established the gnotobiotic pig model of human rotavirus (HRV) infection using cloned pigs with homozygous disruption in the gene encoding immunoglobulin heavy chain (HCKO), which totally impairs B-cell development. To clarify importance of B cells and cytotoxic T cells in rotavirus immunity, CD8 cells in a subset of the pigs were depleted by injecting antipig CD8 antibodies and the immune phenotypes of all pigs were examined.