Altered target organ. A mechanism of postrecovery resistance to murine autoimmune oophoritis.

Experimental murine autoimmune oophoritis, a model of human premature ovarian failure, is induced by immunization with a peptide of the ZP3 glycoprotein from mouse zona pellucida (ZP3(330-340)) in CFA. The ovarian pathology is mediated by ZP3-specific, CD4+ T cells, and not by Abs. We now show that mice recovered from autoimmune oophoritis in 4 mo, as characterized by regression of ovarian inflammation. Recovery was associated with disease resistance upon rechallenge with ZP3(330-340) in CFA. Oophoritis resistance was not explicable by immunosuppressive effect of CFA priming, nor by suppression of pathogenic T cells. ZP3-specific, proliferative T cell response could be detected, and a ZP3-specific, IFN-gamma-producing pathogenic T cell line was derived readily from the recovered mice by in vitro stimulation with the ZP3(330-340) peptide. Moreover, recovered mice, when challenged with ZP3(330-340) in CFA, produced Abs of IgG class to the ZP3(330-340) peptide. Suppressor T cells are not readily demonstrable. Most importantly, oophoritis occurred in normal ovaries implanted under the renal capsule of the recovered mice. That oophoritis developed in the implanted ovaries, but spared the endogenous ovaries, further indicates that the latter is refractory to oophoritis. Disease resistance of the ovaries is not explicable by limitation of accessible target Ags. When mated, recovered mice were fertile and produced normal litters; and, as recipients of a ZP3-specific T cell line, their ovaries developed oophoritis. We conclude that altered local environment of the target organ following autoimmune disease recovery can contribute to the complex disease-resistant state.