Bidirectional Estrogen-Like Effects of Genistein on Murine Experimental Autoimmune Ovarian Disease.

This study was to investigate the bidirectional estrogen-like effects of genistein on murine experimental autoimmune ovarian disease (AOD). Female BALB/c mice were induced by immunization with a peptide from murine zona pellucida. The changes of estrous cycle, ovarian histomorphology were measured, and the levels of serum sex hormone were analyzed using radioimmunoassay. Proliferative responses of the ovary were also determined by immunohistochemistry. Administration of 25 or 45 mg/kg body weight genistein enhanced ovary development with changes in serum sex hormone levels and proliferative responses. Meanwhile, the proportions of growing and mature follicles increased and the incidence of autoimmune oophoritis decreased, which exhibited normal ovarian morphology in administration of 25 or 45 mg/kg body weight genistein, while a lower dose (5 mg/kg body weight genistein) produced the opposite effect. These findings suggest that genistein exerts bidirectional estrogen-like effects on murine experimental AOD, while a high dose (45 mg/kg body weight) of genistein may suppress AOD.

Controlled reperfusion for different durations in the treatment of ischemia-reperfusion injury of the rat ovary: evaluation of biochemical features, molecular gene expression, and histopathology.

High numbers of proinflammatory cells (PMNLs), which are carried by the blood to ischemic tissue during reperfusion, are considered responsible for inducing the inflammatory response that occurs in ischemia-reperfusion (I/R) injury. Our objective was to determine the controlled reperfusion (CR) interval duration (CRID) that would minimize the injury caused by the PMNLs that infiltrate ischemic tissue. Animal groups were divided into the following groups: Sham group, ovarian I/R group (OIR), and ovarian ischemia controlled-reperfusion groups OICR-1, OICR-2, OICR-3, OICR-4, OICR-5, OICR-6, which had their ovarian artery opened and then closed for 10, 8, 6, 4, 2, or 1 s, respectively. The results show that the COX-2 activity and the gene expression decreased while the COX-1 activity and the gene expression were found to be increased in parallel to the shortening of the period in CRID. From the histopathological examinations, the findings of hemorrhage, edema, congested vascular structures, degenerated cells, and migration and adhesion of PMNLs were scaled as follows: Sham group < OICR-6 < OICR-5 < OICR-4 < OICR-3 < OICR-2 < OICR-1. The results from the histopathological assessments were consistent with the molecular and biochemical findings. In conclusion, our findings suggest that increased COX-2 activity plays a role in I/R injury of the rat ovary, and that controlled reperfusion for 3, 2, or 1 s following 2 h of ischemia may attenuate the effects of I/R injury.

Chrono- and Immunocorrection of Inflammatory Disorders of Internal Reproductive Organs in Women of Reproductive Age.

We compared the effectiveness of immunomodulators used in the treatment of patients with chronic salpingitis and oophoritis with or without changes in succinate dehydrogenase (SDH) activity in blood lymphocytes at incubation with the drug. Diurnal variations in individual reaction of SDH in blood lymphocytes to thymalin or ridostin were revealed. In the groups of women receiving ridostin or thymalin during the reaction of lymphocyte SDH to it, improvement of clinical laboratory and immunological parameters was observed in the majority of the patients and no effect was found in a lesser group of patients than in the groups treated with drugs during the absence of lymphocyte SDH reaction thereto. The timing of the presence of SDH reaction to drugs in the immunocompetent cells makes it possible to set the optimal daily regime of their application and to select a drug that would be most effective in each particular case.

H2 control of natural T regulatory cell frequency in the lymph node correlates with susceptibility to day 3 thymectomy-induced autoimmune disease.

Day 3 thymectomy (D3Tx) results in a loss of peripheral tolerance mediated by natural regulatory T cells (nTregs) and development of autoimmune ovarian dysgenesis (AOD) and autoimmune dacryoadenitis (ADA) in A/J and (C57BL/6J × A/J) F(1) hybrids (B6A), but not in C57BL/6J (B6) mice. Previously, using quantitative trait locus (QTL) linkage analysis, we showed that D3Tx-AOD is controlled by five unlinked QTL (Aod1-Aod5) and H2. In this study, using D3Tx B6-Chr(A/J)/NaJ chromosome (Chr) substitution strains, we confirm that QTL on Chr16 (Aod1a/Aod1b), Chr3 (Aod2), Chr1 (Aod3), Chr2 (Aod4), Chr7 (Aod5), and Chr17 (H2) control D3Tx-AOD susceptibility. In addition, we also present data mapping QTL controlling D3Tx-ADA to Chr17 (Ada1/H2), Chr1 (Ada2), and Chr3 (Ada3). Importantly, B6-ChrX(A/J) mice were as resistant to D3Tx-AOD and D3Tx-ADA as B6 mice, thereby excluding Foxp3 as a susceptibility gene in these models. Moreover, we report quantitative differences in the frequency of nTregs in the lymph nodes (LNs), but not spleen or thymus, of AOD/ADA-resistant B6 and AOD/ADA-susceptible A/J, B6A, and B6-Chr17(A/J) mice. Similar results correlating with experimental allergic encephalomyelitis and orchitis susceptibility were seen with B10.S and SJL/J mice. Using H2-congenic mice, we show that the observed difference in frequency of LN nTregs is controlled by Ada1/H2. These data support the existence of an LN-specific, H2-controlled mechanism regulating the prevalence of nTregs in autoimmune disease susceptibility.

Organ-specific autoimmune diseases induced in mice by elimination of T cell subset. I. Evidence for the active participation of T cells in natural self-tolerance; deficit of a T cell subset as a possible cause of autoimmune disease.

Organ-specific autoimmune diseases such as oophoritis, gastritis, thyroiditis, and orchitis were induced in female or male nude (nu/nu) mice by the transfer of nu/+spleen cells from which particular Lyt T cell subset(s) had been removed: nu/+spleen cells treated with anti-Lyt-1 plus complement (C) caused disease in recipient nude mice; anti-Lyt-2 plus C-treated spleen cells, in contrast, did not. The cells responsible for disease induction are believed to be Thy-1+, Lyt-1-, 2,3- (Thy-1, Lyt-1, 2,3), since spleen cells treated with mixed antisera, including anti-Lyt-1 and anti-Lyt-2, plus C, could induce the disease with almost the same incidence as anti-Lyt-1 plus C-treated cells (oophoritis 50%, gastritis 25%, thyroiditis 10-20%, and orchitis 40%). Cells treated with mixed antisera of anti-Thy-1, anti-Lyt-1, and anti-Lyt-2, plus C, could not induce autoimmune disease. Each induced autoimmune disease could be adoptively transferred to other nude mice via spleen cells, with resulting histological lesion of corresponding organs and development of specific circulating autoantibodies. Since anti-Thy-1 plus C treatment of donor spleen cells abrogated the capacity to transfer the disease, we conclude that T cells are required as effector cells, and that these may develop from Lyt-1-, 2,3- cells. Lyt-1+, 2,3- cells were demonstrated to have suppressive activity upon the development of the diseases; induction of autoimmunity was completely inhibited by the cotransfer of Lyt-1+, 2,3- cells with Lyt-1-, 2,3- cells. When anti-Lyt-2 plus C-treated cells (i.e., Lyt-1+, 2,3- and Lyt-1-, 2,3- cells) were mixed with anti-Lyt-1 and anti-Lyt-2 plus C-treated cells (i.e., Lyt-1-, 2,3- cells) in various ratios, then transferred to nude mice, the development of each autoimmune disease was clearly inhibited, even by small doses of Lyt-1+, 2,3- cells. The autoimmune disease we were able to induce was quite similar to human organ-specific autoimmune disease in terms of the spectrum of organs involved, histopathological features, and the development of autoantibodies to corresponding organ components (oocytes, parietal cells, thyroid colloid, including thyroglobulin, and sperm).(ABSTRACT TRUNCATED AT 400 WORDS)

The relative contribution of the CD28 and gp39 costimulatory pathways in the clonal expansion and pathogenic acquisition of self-reactive T cells.

The zona pellucida (ZP), an ovarian extracellular structure, contains three major glycoproteins: ZP1, ZP2, and ZP3. A ZP3 peptide contains both an autoimmune oophoritis-inducing T cell epitope and a B cell epitope that induces autoantibody to ZP. This study investigates two major T cell costimulation pathways in this disease model. Herein we show that blockage of glycoprotein (gp)39 and CD40 interaction with gp39 monoclonal antibody (mAb) results in the failure to induce both autoimmune oophoritis and autoantibody production. Inhibition of ligand binding to the CD28 receptor with the fusion protein, murine CTLA4-immunoglobulin (Ig), also results in failure to generate antibody to ZP and significantly reduces disease severity and prevalence. Surprisingly, the frequencies of antigen-specific T cells in anti-gp39 mAb-treated mice, CTLA4-Ig treated mice, and in mice given control hamster IgG or control fusion protein L6, were equivalent as determined by limiting dilution analysis (approximately equals 1:5,000). These T cells, which produced comparable amounts of interleukin 4 and interferon gamma in vitro, were able to transfer oophoritis to normal recipients. When anti-gp39 mAb and CTLA4-Ig were given together, the effect was additive, leading to inhibition of T cell activation as determined by in vitro proliferation and limiting dilution analysis (approximately equals 1:190,000); disease and antibody responses were absent in these mice. By studying these two costimulatory pathways in parallel, we have shown that autoimmune disease and autoantibody production are inhibitable by blocking either the gp39 or the CD28 pathway, whereas inhibition of clonal expansion of the effector T cell population occurs only when both pathways are blocked.

Study on cellular events in postthymectomy autoimmune oophoritis in mice. I. Requirement of Lyt-1 effector cells for oocytes damage after adoptive transfer.

Neonatal thymectomy during the critical period, 2-4 d after birth, can induce various organ-specific autoimmune diseases including oophoritis in A/J mice. The oophoritis thus induced was passively transferred into neonatal mice by injection of spleen cells obtained from syngeneic donors with the disease. Recipient ovaries were rapidly damaged with remarkable mononuclear cell infiltration and destruction of follicular structures. The phenotype of effector cells responsible for successful adoptive transfer was found to be Thy-1+, Lyt-1+,23-, Ia-, Qa-1-, and was sensitive to antithymocyte serum treatment but resistant to cyclophosphamide treatment or in vitro X-ray irradiation. The compatibility between donor and recipient at the major histocompatibility complex was not required for the effector phase of transfer. The oophoritis induced in BALB/c (nu/+ or +/+) was also shown to be transferred into athymic BALB/c nude mice with resulting ovarian lesion and circulating autoantibodies against oocytes. In this transfer system, the effector cells were also demonstrated to be T cells with the Lyt-1+,23- phenotype. Adoptive transfer experiments in both systems revealed that the destruction of ovaries in postthymectomy autoimmune oophoritis was mediated by Lyt-1 T cells. Whether these T cells can be distinguished from other Lyt-1 cells, such as T helper cells and effector T cells in delayed-type hypersensitivity (DTH), is not clear at present, but the results suggest that the effector mechanisms may be closely related to a DTH reaction.

Study on cellular events in post-thymectomy autoimmune oophoritis in mice. II. Requirement of Lyt-1 cells in normal female mice for the prevention of oophoritis.

Autoimmune oophoritis that develops in A/J mice after neonatally thymectomy (NTx) was prevented by a single intraperitoneal injection of spleen cells or thymocytes from normal adult female mice. Prevention of oophoritis was achieved when spleen cells were given within 2 wk after Tx. When spleen cells were obtained from neonatally oophorectomized mice, four times more cells were required for the prevention of oophoritis, but those from the mice oophorectomized on day 7 after birth had equivalent capacity to prevent oophoritis to those from normal female mice. The spleen cells from normal A/J mice that prevented the development of oophoritis in NTx A/J mice were Thy-1+, Lyt-1+,23-, Ia-, Qa-1-, sensitive to in vitro irradiation with 400 rad, resistant to administration of cyclophosphamide or anti-thymocyte serum, and were not eliminated by adult thymectomy. Thymocytes with oophoritis-preventing capacity were also found to be Lyt-1+,23- and TL-1,2,3-. These results seem to correlate well with the finding that the Lyt-1 subpopulation is substantially decreased in NTx mice. The results suggest that, in this post-thymectomy autoimmune oophoritis, NTx abrogates the Lyt-1 T cell subpopulation that serves as suppressive or regulatory cells over developing self-reactive cells directed toward ovarian antigens, and eventually may cause autoimmune oophoritis.

Autoimmune oophoritis in the adolescent.

Autoimmune oophoritis presents in adolescents as a component of autoimmune polyendocrine syndrome type I or type II. Autoimmune oophoritis can be diagnosed in women with primary ovarian insufficiency in the presence of adrenal cortical or steroid cell antibodies, and/or antibodies to adrenal and ovarian steroidogenic enzymes. The ovaries are cystic macroscopically, with a lymphocytic infiltrate in the steroidogenic theca cells. The immune infiltrate results in low estradiol levels and a compensatory increase in FSH levels. Granulosa cells are spared, and inhibin A and B levels are normal to high. Treatment is aimed at symptom relief with further investigation needed to assess treatment options such as immunosuppression.

Autoimmune disease of the ovary induced by a ZP3 peptide from the mouse zona pellucida.

We describe a novel experimental system in mice for the study of ovarian autoimmune disease, a condition encountered in women with premature ovarian failure. The ovarian autoimmune disease is induced in B6AF1 mice by a 15-amino acid peptide (Cys-Ser-Asn-Ser-Ser-Ser-Ser-Gln-Phe-Gln-Ile-His-Gly-Pro-Arg) from mouse ZP3, the sperm-binding component of the zona pellucida that surrounds growing and mature oocytes. Whereas the peptide induces both T cell and antibody responses, adoptive transfer of CD4+ T cell lines derived from affected animals causes oophoritis without observable antibodies to the zona pellucida peptide. The primacy of the T cell response in the pathogenesis of disease is further substantiated by defining oophoritogenic peptides as small as eight amino acids (Asn-Ser-Ser-Ser-Ser-Gln-Phe-Gln) that do not elicit an antibody response to the full-length ZP3 peptide. The identification of a well characterized peptide as a causative agent of autoimmune oophoritis should facilitate understanding of the pathogenesis of this T cell-mediated autoimmune disease. Because the proteins of the zona pellucida are conserved among mammals (the mouse and human ZP3 proteins are 67% identical), this murine model may lead to better understanding of the pathogenesis of human autoimmune oophoritis.

Antigen mimicry in autoimmune disease sharing of amino acid residues critical for pathogenic T cell activation.

A nonamer peptide from murine nicotinic acetylcholine receptor delta chain (ACR delta), which shared four amino acid residues with a nonamer peptide of murine ovarian zona pellucida glycoprotein ZP3, induced murine autoimmune oophoritis and IgG autoantibody to the zona pellucida. Crossreaction between the ACR delta and ZP3 peptides was established by the response of a ZP3 peptide-specific, oophoritogenic T cell clone to both peptides in association with IA (alpha k beta b). By substituting the ZP3 peptides with a single alanine, four amino acids within the ZP3 peptide were found to be important for ovarian autoimmune disease, autoantibody response, and stimulation of the ZP3-specific T cell clone. Substitution with conservative amino acids of three residues also ablated activity, whereas the fourth, a phenylalanine, was replaceable by tyrosine without loss of activity. Of the four critical amino acids, three were shared between the ZP3 peptide and the ACR delta peptide. Moreover, polyalanine peptides with the four critical ZP3 amino acids or the four amino acids common to the ZP3 and ACR delta peptides induced immune response to ZP3 and elicited severe ovarian autoimmune disease. Thus, organ-specific autoimmune disease can occur through immune response against unrelated self (or foreign) peptides that share with a self-peptide sufficient common amino acid residues critical for activation of pathogenic, autoreactive T cells.

ZP3 peptides administered orally suppress murine experimental autoimmune ovarian disease.

Experimental autoimmune ovarian disease (AOD) is a T cell-mediated chronic inflammatory disease that may lead to premature ovarian failure. Autoimmune disease can be suppressed by oral administration of autoantigens leading to tolerance. One of the major mechanisms of oral tolerance is induction of regulatory CD4+ T cells that can mediate active suppression by producing immunomodulatory cytokines. However, the role of oral tolerance as a treatment for experimental AOD has received little attention. Therefore, the purpose of this study was to examine the conditions necessary to produce oral tolerance in experimental AOD in B6AF1 female mice. In this study, mice received different doses of peptides of the mouse zona pellucida 3 (pZP3) via gastric intubation for 7 times. After 4 times of oral administration, AOD was induced by immunization with pZP3. The optimal tolerating regimen for oral administration of pZP3 in mice was 10 microg, which decreased morbidity of oophoritis compared to the control group. In this moderate-dose therapeutic group (MD), alterations in the estrous cycle were normalized and CD4+ T cells that were CD25+ increased while those that were CD25- decreased. The severity of autoimmune oophoritis and the titer of ZP autoantibodies were also significantly reduced. These findings suggest that oral administration of pZP3 may be successfully used as an oral tolerance strategy for suppression of AOD.

Primary Immunoprevention of Epithelial Ovarian Carcinoma by Vaccination against the Extracellular Domain of Anti-Müllerian Hormone Receptor II.

Epithelial ovarian carcinoma (EOC) is the most prevalent form of ovarian cancer in the United States, representing approximately 85% of all cases and causing more deaths than any other gynecologic malignancy. We propose that optimized control of EOC requires the incorporation of a vaccine capable of inducing safe and effective preemptive immunity in cancer-free women. In addition, we hypothesize that ovarian-specific self-proteins that are "retired" from autoimmune-inducing expression levels as ovaries age but are expressed at high levels in emerging EOC may serve as vaccine targets for mediating safe and effective primary immunoprevention. Here, we show that expression of the extracellular domain of anti-Müllerian hormone receptor II (AMHR2-ED) in normal tissues is confined exclusively to the human ovary, drops to nonautoimmune inducing levels in postmenopausal ovaries, and is at high levels in approximately 90% of human EOC. We found that AMHR2-ED vaccination significantly inhibits growth of murine EOC and enhances overall survival without inducing oophoritis in aged female mice. The observed inhibition of EOC growth was mediated substantially by induction of AMHR2-ED-specific IgG antibodies that agonize receptor signaling of a Bax/caspase-3-dependent proapoptotic cascade. Our results indicate that AMHR2-ED vaccination may be particularly useful in providing safe and effective preemptive immunity against EOC in women at high genetic or familial risk who have the greatest need for a preventive vaccine and ultimately in cancer-free postmenopausal women who account for 75% of all EOC cases. Cancer Prev Res; 10(11); 612-24. ©2017 AACRSee related editorial by Shoemaker et al., p. 607.

Effect of alpha-melanotropin hormone on serum levels of luteinizing hormone and progesterone in experimental rat autoimmune oophoritis.

We studied the effect of alpha-melanotropin hormone (alpha-MSH) on experimental autoimmune oophoritis (EAO), an inflammatory process induced in female rats. During proestrus, serum levels of LH and progesterone in rats with EAO were higher than those of control rats. However, administration of alpha-MSH to these rats decreased the levels of LH. Similarly, in the following diestrus, rats with EAO had high levels of LH but treatment with alpha-MSH decreased the levels to diestrus 2 control values. Treatment with alpha-MSH also reduced the LH levels of control rats in diestrus 2 compared to untreated controls. However, alpha-MSH treatment had no effect on progesterone levels of either control or rats with EAO. Thus, although alpha-MSH induced notable changes in levels of LH, this decrease was unable to block the illness.

Eosinophilic perifolliculitis presenting as a painful cystic ovarian mass in a woman with fibromyalgia: a case report.

BACKGROUND: Autoimmune oophoritis is characterized by an ovarian lymphocytic infiltrate and is a rare finding in women with premature ovarian failure. Eosinophilic perifolliculitis is a possible variant of autoimmune oophoritis, of which the pathogenesis and natural history are largely unknown. CASE: A 45-year-old woman, gravida 2, para 2, status post total abdominal hysterectomy, presented to her internist complaining of cyclic, throbbing, right lower quadrant pain. Her past medical history was significant forfibromyalgia. Pelvic ultrasound demonstrated a 2.3-cm, physiologic-appearing right ovarian cyst. Follow-up ultrasound showed a 2.2-cm, complex cyst on the right ovary that increased in size to 4.2 x 3.2 x 3.5 cm on repeat ultrasound 12 weeks later. Exploratory laparotomy and bilateral salpingo-oophorectomy were performed. Pathologic evaluation of the ovaries revealed a 3 x 2 cm regressing corpus luteal cyst with numerous eosinophils, lymphocytes, macrophages and plasma cells, infiltrating the cyst zoall. Serum antiovarian antibodies were positive. CONCLUSION: The patient's pathologic findings are consistent with the rare entity of eosinophilic perifolliculitis. The patient's history offibromyalgia is of particular interest given that both of these diseases may have an autoimmune etiology. Eosinophilic perifolliculitis should be considered in the differential diagnosis of premenopausal and perimenopausal women with pelvic pain and persistent cystic ovarian enlargement.

Experimental autoimmune oophoritis. II. Both lymphoid cells and antibodies are successful in adoptive transfer.

Experimental autoimmune oophoritis can be readily induced by passive transfer of peripheral blood lymphocytes, lymph node cells, spleen cells, T- and B-enriched cell suspensions, immune serum and gamma globulins, from ovary antigen immunized rats to naive recipients. Adoptive transfer was markedly enhanced when recipient rats were injected simultaneously with sensitized lymphoid cells and anti-ovary antibodies. Histologically, this passively induced disease was much the same as the actively induced disease. By syngeneic lymph node assay it was shown that regional lymph nodes of neonatally thymectomized rats did not enlarge upon injection of EAOO lymphocytes which otherwise produced a marked effect in lymph nodes of normal recipient rats. Therefore, it appears that enlargement of the draining lymph node was dependent on the participation of host T cells. The possibility that development of EAOO may involve cooperation between antigen-reactive and effector classes of lymphocytes was discussed.

Cellular events associated with autoimmune oophoritis and ovarian tumorigenesis in neonatally thymectomized mice.

Thymectomy at 3 days of age (Tx-3) in (C3H/HeMs x 129/J)F1 (C31) female mice results in post-pubertal ovarian dysgenesis associated with high levels of circulating auto-oocyte antibodies (AOA) prior to ovarian tumor formation. Evidence suggests that the etiology for the ovarian dysgenesis resulting from Tx-3 is autoimmune and involves helper T cell abnormalities. The present study characterized circulating leukocytes and mitogenic activity using concanavalin A (ConA) with serologically selected spleen T cells. We observed no sustained abnormalities in either number of circulating leukocytes or percentages of granulocytes or lymphocytes. Circulating mononuclear cells with positive immunofluorescence for Thy 1.2 and Lyt 1.1+Lyt 1.2 cell markers were similar in all mice. However, the spleen cells from Tx-3 mice with ovarian dysgenesis remaining after adsorption with antisera to the Lyt 2.1+Lyt 2.2 antigens (helper T cells remaining) showed increased incorporation of [3H]thymidine compared to the intact mice. This stimulated activity occurred during the periods of early ovarian dysgenesis and active tumor growth. Apparently, the autoimmune oophoritis results from an imbalance within the Lyt 1 cells which may represent a primary insult to the ovary that results in later ovarian tumor development.

Autoimmune oophoritis.

A 43-year-old para 3 woman presented with a six-year history of progressive oligomenorrhea and hypomenorrhea. A total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed for the suspicion of ovarian cysts. On histologic examination, the ovaries contained lymphocytic and plasma cell infiltrates in relation to the theca interna of growing follicles, to the corpora lutea and to the endocrine hilar cells. The infiltrates increased in density with the follicular maturation and culminated against the corpora lutea. The plasma cell population was polyclonal. No antibodies to ovarian tissue components could be demonstrated in the patient's serum by means of immunohistochemistry; but antibodies to the zona glomerulosa of adrenal cortex were detected by serologic means. Although a rare disease, autoimmune oophoritis must be recognized histologically because it is a cause of ovarian failure and because it indicates that the patient is at risk of developing associated Addison's disease.

Microheterogeneity of alpha 1-acid glycoprotein in the sera of patients with cancer or inflammatory states of the ovaries.

alpha 1-Acid glycoprotein (AGP) and its concanavalin A-dependent four microheterogeneous fractions were measured in sera from women with ovarian carcinoma and those with an inflammatory ovarian disease. Total concentrations of AGP in inflammatory and cancerous sera were significantly higher than in control group, but did not differ from each other. In the fourth stage cancer the distribution of Con A-dependent fractions 1, 3 and 4 was significantly different as compared with control, second stage cancer and inflammatory groups.

Contraceptive vaccine assessment based on a murine ZP3 mini-autoantigen.

A summary is presented of published and some unpublished observations from studies on the immunological response of mice to a 13-mer peptide of the murine ovarian zona pellucida glycoprotein ZP3. The findings have the following implications for the design of immunocontraceptive vaccines. To be reversible, a ZP3 vaccine must not contain pathogenic T cell epitopes of ZP3, but contraception without autoimmune oophoritis may be feasible. The immune response to the ZP3 mini-autoantigen is highly variable among inbred mouse strains, suggesting that a single oophoritogenic peptide would not achieve irreversible contraception in an outbred population. The discovery of antigen mimicry at the level of T cell peptide has thrown doubt on the validity of current strategy in detecting relevant self-antigens that might cross react with vaccine immunogens and on the feasibility of fully predicting the cross-reactive autoimmunogenic potential of a peptide or polypeptide vaccine antigen. Autoantibodies directed against epitopes outside the ZP3 mini-autoantigen, produced by immunization with the pure T cell epitope, react with high affinity, with native zona pellucida, and may be useful in identifying B cell epitopes in ZP3.