Xenoantibodies to pig endothelium are expressed in germline configuration and share a conserved immunoglobulin VH gene structure with antibodies to common infectious agents
Kearns-Jonker, M.; Fraiman, M.; Chu, W.; Gochi, E.; Michel, J.; Wu, G.D.; Cramer, D.V.
Transplantation 65(11): 1515-1519
1998
ISSN/ISBN: 0041-1337 PMID: 9645817 Document Number: 486412
Background. The rejection of pig xenografts in humans is initiated by preformed antibodies that may be related to the natural antibodies that formulate a first line of defense against infectious agents. Immunoglobulin gene variable domains encoding the antibodies that react with similar epitopes expressed on xenoantigens and bacteria may share structurally similar antigen-binding site configurations. Methods. We sequenced the VH immunoglobulin genes and germline progenitors of two rat monoclonal antibodies that recognize pig xenoantigens. Nucleic and amino acid sequences of these xenoantibodies were compared with immunoglobulin genes encoding antibodies that react with bacteria or viruses. Results and Conclusions. VH genes encoding rat antipig xenoantibodies are expressed in germline configuration and share structural similarities, including identical amino acids in key antigenic contact sites that define antibody canonical structural groups, with antibodies to infectious agents.