The response of human T lymphocytes to porcine vascular endothelium will be a major factor determining the outcome of clinical tissue or organ xenotransplantation. This response will likely be determined by a combination of direct and indirect recognition of donor peptides expressed on donor or recipient MHC molecules. Studies of in vitro responses indicate the xenogenic human anti-porcine response is surprisingly stronger than the human alloresponse. By contrast, in vivo experimental models show that the xenoresponse is significantly weaker than the alloresponse. We hypothesize that some protein on human endothelial cells is required for in vivo but not in vitro responses and that this protein(s) expressed by porcine cells to a lesser degree or not recognized by human T cells in vivo. The investigators have developed the capacity to genetically transduce endothelial cells with viral vectors with high efficiency. This together with the development of a synthetic collagen/fibronectin gel microvessel system that can be introduced into huPBL/SCID beige mouse models offers a means to define properties of xenorecognition in vivo.
The specific aims of this proposal are: (1) to firmly establish the synthetic microvessel using normal porcine aortic endothelial cells (PAEC) and Bcl-2 transduced Paec, (2) to characterize the interaction of human PBMC with porcine PAEC-derived microvessels in vivo, (3) to genetically modify PAEC to overexpress factors that affect T cell endothelial cell interactions and characterize the consequences in vivo and in the synthetic microvessel system in vivo, and (4) to utilize the information to evaluate the responses in two additional models in the huPBL-SCID being mouse: the porcine arterial graft and the porcine skin graft. These experiments will provide critical information regarding the recognition properties of T cells in a xenograft model that is essential for xenotransplantation.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
1R01HL065744-01
Application #
6194807
Study Section
Pathology A Study Section (PTHA)
Project Start
2000-07-01
Project End
2001-06-30
Budget Start
2000-07-01
Budget End
2001-06-30
Support Year
1
Fiscal Year
2000
Total Cost
$404,305
Indirect Cost
Name
Yale University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
082359691
City
New Haven
State
CT
Country
United States
Zip Code
06520
Zheng, Lian; Gibson, Thomas F; Schechner, Jeffrey S et al. (2004) Bcl-2 transduction protects human endothelial cell synthetic microvessel grafts from allogeneic T cells in vivo. J Immunol 173:3020-6
Strawn, William B; Ferrario, Carlos M (2002) Mechanisms linking angiotensin II and atherogenesis. Curr Opin Lipidol 13:505-12
Tereb, D A; Kirkiles-Smith, N C; Kim, R W et al. (2001) Human T cells infiltrate and injure pig coronary artery grafts with activated but not quiescent endothelium in immunodeficient mouse hosts. Transplantation 71:1622-30