Interleukin-1 receptor antagonist therapy and induction of anterior chamber-associated immune deviation-type tolerance after corneal transplantation.
OBJECTIVE
Topical treatment with interleukin 1 receptor antagonist (IL-1ra) can promote corneal allograft survival by suppressing induction of allodestructive immunity. The purpose of these experiments was to determine whether IL-1ra could also promote induction of allo-protective tolerogenic pathways, including anterior chamber-associated immune deviation (ACAID), which has been shown to participate in long-term survival of corneal transplants.


METHODS
Corneal buttons from BALB/c (syngeneic) or C57BL/6 (fully mismatched allogeneic) mice were orthotopically grafted onto BALB/c recipients. Topical IL-1ra or vehicle alone was applied to grafts three times daily. Donor-specific ACAID was measured in allogeneic grafted mice at 4 and 8 weeks after transplantation by ear-challenging grafted hosts with donor-derived splenocytes 1 week after SC immunization. In separate experiments, grafted mice were treated for 4 weeks before injecting ovalbumin (OVA) into their anterior chambers to determine their capacity to induce antigen-specific ACAID.


RESULTS
Treatment with IL-1ra did not promote, or inhibit, induction of donor-specific ACAID compared with vehicle-treated controls at either the early or late time points studied. However, IL-1ra treatment after transplantation led to significantly earlier restoration of the grafted eyes' capacity for inducing ACAID to soluble antigen (OVA).


CONCLUSIONS
Promotion of OVA-specific ACAID by IL-1ra suggests that suppression of IL-1-mediated mechanisms contributes to recovery of the anterior segment's immunosuppressive microenvironment at least 1 month earlier than would otherwise be seen after corneal transplantation. However, IL-1ra treatment does not alter induction of donor-specific ACAID after transplantation, suggesting that its anti-inflammatory activities do not lead to an ACAID-inducing signal per se. This suggests that IL-1ra promotes graft survival almost exclusively by virtue of suppressing inflammation and not by directly promoting tolerance or antigen-specific regulatory pathways.
Yamada
J
J
Laboratory of Immunology, Schepens Eye Research Institute and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA.
Zhu
S N
SN
Streilein
J W
JW
Dana
M R
MR
D000287:Administration, Topical; D000818:Animals; D000867:Anterior Chamber / Q000276:immunology*; D016039:Corneal Transplantation / Q000276:immunology*; D006085:Graft Survival / Q000187:drug effects* / Q000276:immunology; D006968:Hypersensitivity, Delayed / Q000139:chemically induced / Q000276:immunology / Q000517:prevention & control*; D007108:Immune Tolerance / Q000187:drug effects; D007109:Immunity; D053590:Interleukin 1 Receptor Antagonist Protein; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009883:Ophthalmic Solutions / Q000627:therapeutic use; D010047:Ovalbumin / Q000633:toxicity; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000627:therapeutic use; D012795:Sialoglycoproteins / Q000627:therapeutic use*; D014184:Transplantation, Homologous
C507764:Il1rn protein, mouse; D053590:Interleukin 1 Receptor Antagonist Protein; D009883:Ophthalmic Solutions; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; D012795:Sialoglycoproteins; D010047:Ovalbumin