Role of tumor necrosis factor receptor expression in anterior chamber-associated immune deviation (ACAID) and corneal allograft survival.
OBJECTIVE
To determine the role of tumor necrosis factor receptors (TNFRs) in corneal allograft rejection.


METHODS
Corneal epithelial and endothelial cells were examined by flow cytometry for the expression of TNFRI and TNFRII and their susceptibility to TNF-alpha-induced apoptosis. Corneal allografts from normal and TNFRI and TNFRII knockout (KO) C57BL/6 mice were transplanted to BALB/c hosts, and the fate of the allografts was monitored. C57BL/6 spleen cells were injected into the anterior chamber (AC) of BALB/c mice to induce anterior chamber-associated immune deviation (ACAID) and promote corneal allograft survival. The presence of ACAID suppressor cells in corneal allograft recipients was tested using a local adoptive transfer (LAT) assay.


RESULTS
Murine corneal epithelial and endothelial cells expressed TNFRI and TNFRII and were susceptible to TNF-alpha-induced apoptosis, yet corneal allografts from either TNFRI or TNFRII donors did not enjoy a lower incidence of rejection or a prolongation in survival time compared to corneal allografts from normal C57BL/6 donors. Moreover, all 31 of the TNFRII KO corneal grafts were rejected by naïve BALB/c hosts. Rejection of TNFRII KO corneal grafts occurred even though suppressor cells developed in the hosts and inhibited the expression of delayed-type hypersensitivity to donor alloantigens.


CONCLUSIONS
Expression of TNFRII on corneal cells conveys a degree of protection against immune rejection of corneal allografts by a mechanism that is independent of ACAID. Moreover, induction of ACAID before the application of TNFRII KO corneal allografts fails to improve survival and does not replace the TNFRII-dependent protective mechanism.
Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, 75390-9057, USA. jerry.niederkorn@utsouthwestern.edu
Jerry Y
JY
Niederkorn
Elizabeth
E
Mayhew
Jessamee
J
Mellon
Sushma
S
Hegde
D019264:Adoptive Transfer; D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D000867:Anterior Chamber / Q000276:immunology*; D015703:Antigens, CD / Q000502:physiology*; D017209:Apoptosis / Q000187:drug effects; D004728:Endothelium, Corneal / Q000378:metabolism; D019573:Epithelium, Corneal / Q000378:metabolism; D005434:Flow Cytometry; D006084:Graft Rejection / Q000517:prevention & control; D006085:Graft Survival / Q000502:physiology*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007519:Isoantigens / Q000276:immunology; D015948:Keratoplasty, Penetrating / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018124:Receptors, Tumor Necrosis Factor / Q000502:physiology*; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D050378:T-Lymphocytes, Regulatory; D014184:Transplantation, Homologous; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D017304:Annexin A5; D015703:Antigens, CD; D007519:Isoantigens; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D014409:Tumor Necrosis Factor-alpha