title: Rat corneal allograft survival prolonged by the superantigen staphylococcal enterotoxin B.
abstract: OBJECTIVE
  The purpose of this study was to determine the optimal conditions for prolonging corneal allograft survival by inducing anergy with the superantigen staphylococcal enterotoxin B (SEB).
  
  
  METHODS
  A rat model of penetrating keratoplasty, whereby Fisher344 donor corneas are implanted into Lewis recipients, was used to evaluate the effects of SEB on inhibiting immune-mediated allograft rejection. To induce anergy, SEB was injected into the peribulbar space of Lewis rats. Furthermore, histopathology and immunofluorescent staining were used to examine the levels of infiltrating CD4(+) and CD8(+) T lymphocytes and NK1.1(+) lymphocytes.
  
  
  RESULTS
  By administering SEB, at doses of 90 or 120 micro g/kg 7 days before and after keratoplasty, we suppressed the episode of corneal graft rejection for a median of 12 and 30 days, respectively. In contrast, rejection was observed when 30 or 60 micro g/kg of SEB was administered. After SEB injections, lymphocyte infiltration into the corneal grafts was reduced, and the expression of NK1.1(+) lymphocytes was enhanced, suggesting that anergy may be occurring. Also, there were no differences in the number of infiltrating CD4(+) and CD8(+) T lymphocytes cells between the control group and groups injected with 30 and 120 micro g/kg SEB on postoperative days 10 and 30.
  
  
  CONCLUSIONS
  Inducing anergy with the superantigen SEB prolonged corneal graft survival in a rat model of penetrating keratoplasty. Therefore, these results support the possibility of prolonging corneal allograft survival in a clinical setting by preventing immune-mediated rejection through the administration of the superantigen SEB.
authors.affiliation: Beijing Institute of Ophthalmology, Beijing TongRen Eye Center, Capital University of Medical Sciences, Beijing, China. ebank416@msn.com
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Pan
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Wenhua
authors.initials: W
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Jie
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Yuying
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D017635:Clonal Anergy; D003315:Cornea / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D004768:Enterotoxins / Q000494:pharmacology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006085:Graft Survival / Q000187:drug effects* / Q000276:immunology; D015948:Keratoplasty, Penetrating; D007694:Killer Cells, Natural / Q000276:immunology; D051381:Rats; D011916:Rats, Inbred F344; D011917:Rats, Inbred Lew; D013211:Staphylococcus aureus; D018089:Superantigens / Q000494:pharmacology*; D014184:Transplantation, Homologous
chemical_list: D004768:Enterotoxins; D018089:Superantigens; C031818:enterotoxin B, staphylococcal