title: Effect of major histocompatibility complex expression on murine intestinal graft survival.
abstract: BACKGROUND
  Clinical intestinal transplantation has been plagued by frequent and severe graft rejection. It has been proposed that the major histocompatibility complex (MHC) antigens might play a critical role in this process owing to their extensive expression on enterocytes and mucosa-associated immune cells.
  
  
  METHODS
  The present study examined the role of MHC antigens in intestinal graft rejection using MHC class I-deficient and MHC class II-deficient donors.
  
  
  RESULTS
  Grafts with normal MHC expression were rejected by 9 days, whereas survival was prolonged to 14 days in the MHC class II-deficient grafts (P=NS) and to 20 days in the MHC I-deficient grafts (P<0.002). In all groups, early rejection was characterized by (1) increased crypt cell apoptosis, as detected by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) technique of in situ labeling; and (2) the increased expression of perforin and a CD8 phenotype in the graft-infiltrating cells.
  
  
  CONCLUSIONS
  These data suggest that MHC antigens, CD8-positive T cells, and perforin-expressing cells contribute to intestinal graft rejection. Apoptosis of the progenitor epithelial crypt cells during early intestinal rejection may impair the gut's ability to regenerate and repair mucosal damage.
authors.affiliation: Department of Surgery, London Health Sciences Centre, Ontario, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Cagiannos
authors.forename: R
authors.initials: R
authors.lastname: Zhong
authors.forename: Z
authors.initials: Z
authors.lastname: Zang
authors.forename: J
authors.initials: J
authors.lastname: Jiang
authors.forename: B M
authors.initials: BM
authors.lastname: Garcia
authors.forename: S
authors.initials: S
authors.lastname: Chakrabarti
authors.forename: A M
authors.initials: AM
authors.lastname: Jevnikar
authors.forename: N R
authors.initials: NR
authors.lastname: Sinclair
authors.forename: D R
authors.initials: DR
authors.lastname: Grant
mesh_terms: D000818:Animals; D017209:Apoptosis; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology; D015870:Gene Expression; D006084:Graft Rejection / Q000235:genetics; D006085:Graft Survival / Q000235:genetics; D007422:Intestines / Q000637:transplantation*; D008285:Major Histocompatibility Complex / Q000235:genetics*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011182:Postoperative Care; D051381:Rats; D013997:Time Factors; D014181:Transplantation Immunology; D014184:Transplantation, Homologous / Q000473:pathology