Accelerated corneal graft rejection in baby rats.
BACKGROUND
Penetrating keratoplasty in infants has a very poor outcome compared to adults. It is of intrinsic interest to gain insight into the still unknown immunological mechanisms of graft failure because any form of uncorrected corneal opacity leads to amblyopia.


METHODS
Allogeneic keratoplasty was performed between Lewis and Fisher rats. The recipients' ages were 10 and 3 weeks, respectively. All experiments were controlled syngeneically. Survival rates were calculated and cellular infiltrates analysed histologically.


RESULTS
Median graft survival times were 15 days in old recipients and 9 days in young recipients (p<0.01). There were fewer infiltrating cells in the younger rats than in the older ones on the day of rejection. Despite the fact that T cells dominated there were significantly more NK cells in young recipients at all time points after transplantation when compared to old recipients.


CONCLUSIONS
An animal model has been established that shows similar rejection kinetics as in children, that is corneal graft failure occurs sooner in young rats. Already little infiltration was sufficient to reject a corneal allograft. The dominance of infiltrating NK cells and the vigorous rejection process suggest an involvement of the innate immune system in this process.
Schwartzkopff
Johannes
J
University Eye Hospital, Killianstrasse 5, D-79106 Freiburg, Germany. johannes.schwartzkopff@uniklinik-freiburg.de
Berger
Moritz
M
Birnbaum
Florian
F
Böhringer
Daniel
D
Reinhard
Thomas
T
D056704:Adaptive Immunity; D000367:Age Factors; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D006084:Graft Rejection / Q000276:immunology* / Q000473:pathology; D007113:Immunity, Innate; D015948:Keratoplasty, Penetrating; D007694:Killer Cells, Natural / Q000276:immunology; D011184:Postoperative Period; D051381:Rats; D011916:Rats, Inbred F344; D011917:Rats, Inbred Lew; D014181:Transplantation Immunology