Prevalence of antitumor antibodies in laying hen model of human ovarian cancer

Ovarian Cancer: Applications of Chickens to Humans

The lack of preclinical models of spontaneous ovarian cancer (OVCA), a fatal gynecological malignancy, is a significant barrier to generating information on early changes indicative of OVCA. In contrast to rodents, laying hens develop OVCA spontaneously, with remarkable similarities to OVCA in women regarding tumor histology, OVCA dissemination, immune responses, and risk factors. These important features of OVCA will be useful to develop an early detection test for OVCA, which would significantly reduce mortality rates; preventive strategies; immunotherapeutics; prevention of resistance to chemotherapeutics; and exploration of gene therapies. A transvaginal ultrasound (TVUS) imaging method for imaging of hen ovarian tumors has been developed. Hens can be monitored prospectively by using serum markers, together with TVUS imaging, to detect early-stage OVCA, provided that a panel of serum markers can be established and imaging agents developed. Recent sequencing of the chicken genome will further facilitate the hen model to explore gene therapies against OVCA.

Inflammasome expression is higher in ovarian tumors than in normal ovary

Chronic inflammation fundamentally influences cancer risk and development. A mechanism of chronic inflammation is the formation of inflammasome complexes which results in the sustained secretion of the pro-inflammatory cytokines IL1β and IL18. Inflammasome expression and actions vary among cancers. There is no information on inflammasome expression in ovarian cancer (OvCa). To determine if ovarian tumors express inflammasome components, mRNA and protein expression of NLRP3 (nucleotide-binding domain, leucine-rich repeat family, pyrin domain containing 3), caspase-1, IL1β, and IL18 expression in hen and human OvCa was assessed. Chicken (hen) OvCa a valid model of spontaneous human OvCa. Hens were selected into study groups with or without tumors using ultrasonography; tumors were confirmed by histology, increased cellular proliferation, and expression of immune cell marker mRNA. mRNA expression was higher for hallmarks of inflammasome activity (caspase-1, 5.9x increase, p = 0.04; IL1β, 4x increase, p = 0.04; and IL18, 7.8x increase, p = 0.0003) in hen OvCa compared to normal ovary. NLRP3, caspase-8 and caspase-11 mRNA did not differ significantly between tumor and non-tumor containing ovaries. Similar results occurred for human OvCa. Protein expression by immunohistochemistry paralleled mRNA expression and was qualitatively higher in tumors. Increased protein expression of caspase-1, IL1β, and IL18 occurred in surface epithelium, tumor cells, and immune cells. The aryl hydrocarbon receptor (AHR), a potential tumor suppressor and NLRP3 regulator, was higher in hen (2.4x increase, p = 0.002) and human tumors (1.8x increase, p = 0.038), suggesting a role in OvCa. Collectively, the results indicate that inflammasome expression is associated with hen and human OvCa, although the NLR sensor type remains to be determined.

Enhancement of Ovarian Tumor Detection by DR6-Targeted Ultrasound Imaging Agents in Laying Hen Model of Spontaneous Ovarian Cancer

OBJECTIVE

The lack of an effective early detection test leads to high case to death ratio of women with ovarian cancer (OVCA). To improve early detection, tumor-associated imaging targets need to be established and imaging agents to image these targets need to be developed. Targeted imaging agents offer potential for improvement of signal intensities from their targets. Expression of death receptor 6 (DR6) by ovarian malignant cells and tumor-associated microvessels increases during OVCA development and represents a novel target for ultrasound imaging. The goal of this study was to examine the feasibility of newly developed DR6-targeted ultrasound imaging agents in enhancing early detection of ovarian tumors in laying hen model of spontaneous OVCA.

MATERIALS AND METHODS

The study was conducted in an exploratory cross-sectional design using 4-year-old laying hens (n = 130). DR6-targeted imaging agents were developed by conjugating microbubbles with rabbit anti-chicken DR6 antibodies. Changes in signal intensity of ultrasound imaging were determined before and after injection of targeted imaging agents in hens with or without spontaneous OVCA. Following targeted imaging, normal or tumor ovaries were processed for histopathological and immunohistochemical studies.

RESULTS

DR6-targeted imaging agents bound with their targets expressed by malignant cells and tumor-associated microvessels in the ovary. Compared with pretargeted imaging, targeted imaging is enhanced by approximately 40% ultrasound echo signal intensity (P < 0.001) from early- and late-stage OVCA. Differences in signal enhancement were not observed among different histological subtypes of OVCA at early or late stages. Higher imaging signal intensities were associated with enhancement in DR6 expression by ovarian malignant cells and increase in the frequency of DR6-expressing microvessels during OVCA development.

CONCLUSIONS

The results of this study suggest that DR6-targeted imaging agents enhance the visualization of ovarian tumors and tumor-associated microvessels in hens with early-stage OVCA and will form a foundation for clinical studies.

Female Reproductive System and Immunology

Health of the reproductive organs is essential for formation and production of high quality and hygienic eggs. It is of importance to review the structures and functions of female reproductive system for better understanding of the mechanism by which the eggs are formed. The unique functions of ovarian cells for follicular growth and differentiation as well as steroidogenesis and oocyte maturation are regulated by gonadotropins and gonadal steroids. The oviduct is responsible for egg formation, while the unique function to store sperms for a prolonged period takes place in the specific tissue of this organ. The unique innate and adaptive immuno-defense systems that play essential role to prevent infection are developed in the ovary and oviduct. Toll-like receptors (TLRs) that recognize the molecular pattern of microbes and initiate the immunoresponse are expressed in those organs. Avian β-defensins (AvBDs), a member of antimicrobial peptides, are synthesized by the ovarian and oviductal cells. Challenge of those cells by TLR ligands upregulates the expression of proinflammatory cytokines, which in turn stimulate the expression of AvBDs. The adaptive immune system in the ovary and oviduct is also unique, since the migration of lymphocytes is enhanced by estrogens. In contrast to the development of immuno-defense system, spontaneous ovarian cancer and uterine fibroids appear more frequently in chickens than in mammals, and thus chickens could be used as a model for studying these diseases. Thus the avian reproductive organs have unique functions not only for egg formation but also for the immuno-defense system, which is essential for prevention of infection and production of hygienic eggs.

Selenium-Binding Protein 1 (SBP1) autoantibodies in ovarian disorders and ovarian cancer

Infertility is a risk factor for ovarian cancer (OvCa). The goal was to determine if antibodies to selenium-binding protein 1 (SBP1), an autoantibody we identified in patients with premature ovarian failure (POF), occurs in both infertility and OvCa patients, and thus could be associated with preneoplasia. Anti-SBP1 was measured by immunoassay against recombinant SBP1, in sera from OvCa (n = 41), infertility (n = 92) and control (n = 87) patients. Infertility causes were POF, unexplained, irregular ovulation or endometriosis. The percent of anti-SBP1-positive sera was higher in POF (P = 0.02), irregular ovulation (P = 0.001), unexplained causes (P = 0.02), late (III-IV)-stage OvCa (P = 0.02) but was not significant in endometriosis, benign ovarian tumors/cysts, early stage (I-II) OvCa or uterine cancer compared to healthy controls. Anti-SBP1 was significantly higher in women with serous (P = 0.04) but not non-serous (P = 0.33) OvCa compared to controls. Also, we determined if anti-SBP1 was associated with CA125 or anti-TP53, markers often studied in OvCa. Anti-TP53 and CA125 were measured by established immunoassays. The ability of anti-SBP1 alone to discriminate infertility or OvCa from controls or when combined with anti-TP53 and CA125, to identify OvCa was evaluated by comparing the area under the curve (AUC) in ROC analysis. Anti-SBP1 alone discriminated infertility (AUC = 0.7; P = 0.001) or OvCa (AUC = 0.67; P = 0.03) from controls. The sensitivity and specificity of OvCa identification was increased by combining CA125, anti-TP53 and anti-SBP1 (AUC = 0.96). Therefore, anti-SBP1 occurs in infertile women with POF, ovulatory disturbances or unexplained infertility and in serous OvCa. This suggests an autoimmune process is associated with the development of serous OvCa.

Association of Immunosuppression with DR6 Expression during the Development and Progression of Spontaneous Ovarian Cancer in Laying Hen Model

Ovarian cancer (OVCA) mainly disseminates in the peritoneal cavity. Immune functions are important to prevent OVCA progression and recurrence. The mechanism of immunosuppression, a hallmark of tumor progression, is not well understood. The goal of this study was to determine the immune system's responses and its suppression during OVCA development and progression in hens. Frequencies of CD8+ T cells and IgY-containing cells and expression of immunosuppressors including IRG1 and DR6 in OVCA at early and late stages in hens were examined. Frequencies of stromal but not the intratumoral CD+8 T cells and IgY-containing cells increased significantly (P < 0.01) during OVCA development and progression. Tumor progression was associated with increased expression of IRG1 and DR6 and decreased infiltration of immune cells into the tumor. Frequency of stromal but not intratumoral immune cells increases during OVCA development and progression. Tumor-induced IRG1 and DR6 may prevent immune cells from invading the tumor.

Common mechanisms of onset of cancer and neurodegenerative diseases

Onset of cancer and neurodegenerative disease occurs by abnormal cell growth and neuronal cell death, respectively, and the number of patients with both diseases has been increasing in parallel with an increase in mean lifetime, especially in developed countries. Although both diseases are sporadic, about 10% of the diseases are genetically inherited, and analyses of such familial forms of gene products have contributed to an understanding of the molecular mechanisms underlying the onset and pathogenesis of these diseases. I have been working on c-myc, a protooncogene, for a long time and identified various c-Myc-binding proteins that play roles in c-Myc-derived tumorigenesis. Among these proteins, some proteins have been found to be also responsible for the onset of neurodegenerative diseases, including Parkinson's disease, retinitis pigmentosa and cerebellar atrophy. In this review, I summarize our findings indicating the common mechanisms of onset between cancer and neurodegenerative diseases, with a focus on genes such as DJ-1 and Myc-Modulator 1 (MM-1) and signaling pathways that contribute to the onset and pathogenesis of cancer and neurodegenerative diseases.

Discovery of prognostic factors for diagnosis and treatment of epithelial-derived ovarian cancer from laying hens

Ovarian cancer is a lethal gynecological cancer causing cancer-related deaths in women worldwide. It is difficult to diagnosis at an early stage when more than 90% patients can be cured because of lack of specific symptoms and early detection markers. Most of malignant ovarian tumors are originated from the germinal epithelium of the ovary. For investigation with animal models of epithelial-derived ovarian cancer (EOC), laying hens are the most relevant animal models because they spontaneously develop EOC as occurs in women through ovulating almost every day. As in women, EOC in the hen is age-related and grossly and histologically similar to that in women. However, domesticated animals are inappropriate for research human EOC due to multiple pregnancies and lactating or seasonally anestrous. In addition, the non-spontaneous nature of rodents EOC limits clinical relevance with human EOC. Recent studies have shown that ovarian cancer could arise from epithelium from the oviduct as oviduct-related genes are up-regulated in EOC of hens. Therefore, we showed in the review: 1) characterization and classification of EOC; 2) chicken models for EOC; 3) relationship estrogen with EOC; 4) candidate prognostic factors for EOC including serpin peptidase inhibior, clade B (ovalbumin), member 3 (SERPINB3), SERPINB11, gallicin 11 (GAL11), secreted phosphoprotein 1 (SPP1) and alpha 2 macroglobulin (A2M) in normal and cancerous ovaries of laying hens; 5) biological roles of microRNAs in development of EOC. Collectively, the present reviews indicate that expression of SERPINB3, SERPINB11, GAL11, SPP1 and A2M is clearly associated with the development of ovarian carcinogenesis. These results provide new insights into the prognostic biomarkers for EOC to diagnose and to evaluate responses to therapies for treating EOC of humans.

Towards an animal model of ovarian cancer: cataloging chicken blood proteins using combinatorial peptide ligand libraries coupled with shotgun proteomic analysis for translational research

Epithelial ovarian cancer is the most deadly gynecological cancer around the world, with high morbidity in industrialized countries. Early diagnosis is key in reducing its morbidity rate. Yet, robust biomarkers, diagnostics, and animal models are still limited for ovarian cancer. This calls for broader omics and systems science oriented diagnostics strategies. In this vein, the domestic chicken has been used as an ovarian cancer animal model, owing to its high rate of developing spontaneous epithelial ovarian tumors. Chicken blood has thus been considered a surrogate reservoir from which cancer biomarkers can be identified. However, the presence of highly abundant proteins in chicken blood has compromised the applicability of proteomics tools to study chicken blood owing to a lack of immunodepletion methods. Here, we demonstrate that a combinatorial peptide ligand library (CPLL) can efficiently remove highly abundant proteins from chicken blood samples, consequently doubling the number of identified proteins. Using an integrated CPLL-1DGE-LC-MSMS workflow, we identified a catalog of 264 unique proteins. Functional analyses further suggested that most proteins were coagulation and complement factors, blood transport and binding proteins, immune- and defense-related proteins, proteases, protease inhibitors, cellular enzymes, or cell structure and adhesion proteins. Semiquantitative spectral counting analysis identified 10 potential biomarkers from the present chicken ovarian cancer model. Additionally, many human homologs of chicken blood proteins we have identified have been independently suggested as diagnostic biomarkers for ovarian cancer, further triangulating our novel observations reported here. In conclusion, the CPLL-assisted proteomic workflow using the chicken ovarian cancer model provides a feasible platform for translational research to identify ovarian cancer biomarkers and understand ovarian cancer biology. To the best of our knowledge, we report here the most comprehensive survey of the chicken blood proteome to date.

Dietary supplementation of Ashwagandha (Withania somnifera, Dunal) enhances NK cell function in ovarian tumors in the laying hen model of spontaneous ovarian cancer

PROBLEM

Ovarian cancer (OVCA) disseminates in a distinct pattern through peritoneal metastasis and little is known about the immunosuppression in the tumor microenvironment. Our goal was to determine changes in NK cell population during OVCA development and the effects of Ashwagandha (Withania somnifera, Dunal) supplementation on NK cell localization in laying hens with OVCA.

METHODS

Frequency of NK cells in ovarian tumors at early and late stages in 3- to 4-year-old hens (exploratory study) as well as in hens supplemented with dietary Ashwagandha root powder for 90 days (prospective study) was examined.

RESULTS

The population of stromal NK cells but not the intratumoral NK cells increased with OVCA development and progression. Ashwagandha supplementation decreased the incidence and progression of OVCA. Both the stromal and intratumoral NK cell population increased significantly (P < 0.0001) in Ashwagandha supplementated hens.

CONCLUSION

The results of this study suggest that the population of stromal and tumorinfiltrating NK cells is increased by dietary Ashwagandha supplementation. Thus, Ashwagandha may enhance antitumor function of NK cells. This study may be useful for a clinical study to determine the effects of dietary Ashwagandha on NK cell immune function in patients with ovarian cancer.

Immune cells in the normal ovary and spontaneous ovarian tumors in the laying hen (Gallus domesticus) model of human ovarian cancer

Background

Spontaneous ovarian cancer in chickens resembles human tumors both histologically and biochemically. The goal was to determine if there are differences in lymphocyte content between normal ovaries and ovarian tumors in chickens as a basis for further studies to understand the role of immunity in human ovarian cancer progression.

Methods

Hens were selected using grey scale and color Doppler ultrasound to determine if they had normal or tumor morphology. Cells were isolated from ovaries (n = 6 hens) and lymphocyte numbers were determined by flow cytometry using antibodies to avian CD4 and CD8 T and B (Bu1a) cells. Ovarian sections from another set of hens (n = 26) were assessed to verify tumor type and stage and to count CD4, CD8 and Bu1a immunostained cells by morphometric analysis.

Results

T and B cells were more numerous in ovarian tumors than in normal ovaries by flow cytometry and immunohistochemistry. There were less CD4+ cells than CD8+ and Bu1a+ cells in normal ovaries or ovarian tumors. CD8+ cells were the dominant T cell sub-type in both ovarian stroma and in ovarian follicles compared to CD4+ cells. Bu1a+ cells were consistently found in the stroma of normal ovaries and ovarian tumors but were not associated with follicles. The number of immune cells was highest in late stage serous tumors compared to endometrioid and mucinous tumors.

Conclusions

The results suggest that similar to human ovarian cancer there are comparatively more immune cells in chicken ovarian tumors than in normal ovaries, and the highest immune cell content occurs in serous tumors. Thus, this study establishes a foundation for further study of tumor immune responses in a spontaneous model of ovarian cancer which will facilitate studies of the role of immunity in early ovarian cancer progression and use of the hen in pre-clinical vaccine trials.

Epithelial ovarian cancer experimental models

Epithelial ovarian cancer (OvCa) is associated with high mortality and, as the majority (>75%) of women with OvCa have metastatic disease at the time of diagnosis, rates of survival have not changed appreciably over 30 years. A mechanistic understanding of OvCa initiation and progression is hindered by the complexity of genetic and/or environmental initiating events and lack of clarity regarding the cell(s) or tissue(s) of origin. Metastasis of OvCa involves direct extension or exfoliation of cells and cellular aggregates into the peritoneal cavity, survival of matrix-detached cells in a complex ascites fluid phase and subsequent adhesion to the mesothelium lining covering abdominal organs to establish secondary lesions containing host stromal and inflammatory components. Development of experimental models to recapitulate this unique mechanism of metastasis presents a remarkable scientific challenge, and many approaches used to study other solid tumors (for example, lung, colon and breast) are not transferable to OvCa research given the distinct metastasis pattern and unique tumor microenvironment (TME). This review will discuss recent progress in the development and refinement of experimental models to study OvCa. Novel cellular, three-dimensional organotypic, and ex vivo models are considered and the current in vivo models summarized. The review critically evaluates currently available genetic mouse models of OvCa, the emergence of xenopatients and the utility of the hen model to study OvCa prevention, tumorigenesis, metastasis and chemoresistance. As these new approaches more accurately recapitulate the complex TME, it is predicted that new opportunities for enhanced understanding of disease progression, metastasis and therapeutic response will emerge.

Three are better than one: plasminogen receptors as cancer theranostic targets

Activation of plasminogen on the cell surface initiates a cascade of protease activity with important implications for several physiological and pathological events. In particular, components of the plasminogen system participate in tumor growth, invasion and metastasis. Plasminogen receptors are in fact expressed on the cell surface of most tumors, and their expression frequently correlates with cancer diagnosis, survival and prognosis. Notably, they can trigger multiple specific immune responses in cancer patients, highlighting their role as tumor-associated antigens. In this review, three of the most characterized plasminogen receptors involved in tumorigenesis, namely Annexin 2 (ANX2), Cytokeratin 8 (CK8) and alpha-Enolase (ENOA), are analyzed to ascertain an overall view of their role in the most common cancers. This analysis emphasizes the possibility of delineating new personalized therapeutic strategies to counteract tumor growth and metastasis by targeting plasminogen receptors, as well as their potential application as cancer predictors.

Human epididymis protein 4 in cancer diagnostics: a promising and reliable tumor marker

Human epididymis protein 4 (HE4) is a member of the "four-disulfide core" family that comprises a heterogeneous group of small acid- and heat-stable proteins of divergent function. Although there is an exponential growth of evidence that HE4 is a valuable tumor marker for ovarian malignancies, the exploration of the usefulness of this glycoprotein in the large tumor landscape is still ongoing. Enzyme-linked immunosorbent assay, chemiluminescent microparticle immunoassay, and bead-based array system are the preferred analytical methods for measuring HE4 concentration. Serum and urinary HE4 levels appear to be more affected by carcinogenesis than by other pathologic processes. Apart from the malignancy itself, histological type of cancer, cancer stage, and menopausal status affects HE4 concentration. An important objective in nowadays research remains the development of a tumor marker panel with a sufficient accuracy for risk assessment, early diagnosis, prognosis, and response to therapeutic treatment of cancer.

Expression of death receptor 6 by ovarian tumors in laying hens, a preclinical model of spontaneous ovarian cancer

Tumor-associated neoangiogenesis and suppression of antitumor immunity are hallmarks of tumor development and progression. Death receptor 6 (DR6) has been reported to be associated with suppression of antitumor immunity and tumor progression in several malignancies. However, expression of DR6 by malignant ovarian epithelial tumors at an early stage is unknown. The goals of this study were to determine whether DR6 is expressed by malignant ovarian epithelial tumors at an early stage and to examine whether DR6 expression is associated with ovarian cancer (OVCA) progression in a laying hen model of spontaneous OVCA. Expression of DR6 was examined in normal and malignant ovaries, normal ovarian surface epithelial (OSE) cells, or malignant epithelial cells and in serum of 3-year-old hens. The population of microvessels expressing DR6 was significantly higher in hens with early-stage OVCA than hens with normal ovaries (P < .01) and increased further in late-stage OVCA. The results of this study showed that, in addition to microvessels, tumor cells in the ovary also express DR6 with a significantly higher intensity than normal OSE cells. Similar patterns of DR6 expression were also observed by immunoblot analysis and gene expression studies. Furthermore, DR6 was also detected in the serum of hens. In conclusion, DR6 expression is associated with OVCA development and progression in laying hens. This study may be helpful to examine the feasibility of DR6 as a useful surrogate marker of OVCA, a target for antitumor immunotherapy and molecular imaging and thus provide a foundation for clinical studies.

Expression of Leukocyte Inhibitory Immunoglobulin-like Transcript 3 Receptors by Ovarian Tumors in Laying Hen Model of Spontaneous Ovarian Cancer

Attempts to enhance a patient's immune response and ameliorate the poor prognosis of ovarian cancer (OVCA) have largely been unsuccessful owing to the suppressive tumor microenvironment. Leukocyte immunoglobulin-like transcript 3 (ILT3) inhibitory receptors have been implicated in immunosuppression in several malignancies. The expression and role of ILT3 in the progression of ovarian tumors are unknown. This study examined the expression and association of ILT3 in ovarian tumors in laying hens, a spontaneous preclinical model of human OVCA. White Leghorn laying hens were selected by transvaginal ultrasound scanning. Serum and normal ovaries or ovarian tumors were collected. The presence of tumors and the expression of ILT3 were examined by routine histology, immunohistochemistry, Western blot analysis, and reverse transcription-polymerase chain reaction. In addition to stromal immune cell-like cells, the epithelium of the ovarian tumors also expressed ILT3 with significantly high intensity than normal ovaries. Among different subtypes of ovarian carcinomas, serous OVCA showed the highest ILT3 staining intensity, whereas endometrioid OVCA had the lowest intensity. Similar to humans, an immunoreactive protein band of approximately 55 kDa for ILT3 was detected in the ovarian tumors in hens. The patterns of ILT3 protein and messenger RNA expression by ovarian tumors in different subtypes and stages were similar to those of immunohistochemical staining. The results of this study suggest that laying hens may be useful to generate information on ILT3-associated immunosuppression in OVCA. This animal model also offers the opportunity to develop and test anti-ILT3 immunotherapy to enhance antitumor immunity against OVCA in humans.

The hen model of human ovarian cancer develops anti-mesothelin autoantibodies in response to mesothelin expressing tumors

Objective

Study of the hen immune system led to seminal contributions to basic immunological principles. Recent studies of spontaneous ovarian cancer in the laying hen show strikingly similar tumor types and antigen expression compared to human ovarian cancer, suggesting hens would be valuable for studies of tumor immunology and pre-clinical vaccine development. Circulating mesothelin is a relatively specific marker for human ovarian cancer and autoantibodies to mesothelin were reported. We hypothesized that hen tumors express mesothelin and that circulating anti-mesothelin antibodies occur in response to tumors.

Methods

Mesothelin mRNA expression was analyzed by RT-PCR in hen ovarian tumors and normal ovaries. Mesothelin protein expression was evaluated by immunohistochemistry (IHC) and two-dimensional SDS-PAGE Western blots. Anti-mesothelin antibodies were assessed by immunoassay of sera from hens with normal ovaries and with ovarian tumors.

Results

Significant mesothelin mRNA expression was observed in 57% (12/21) of hen ovarian tumors but not in normal ovaries and was found predominantly in serous tumors as in humans. Mesothelin protein was detected in tumors with mesothelin mRNA by IHC and 2D Western blots, but not in normal ovaries or tumors without mesothelin mRNA. Circulating anti-mesothelin antibodies occurred in 44% (n = 4/9) of hens with ovarian tumors which express mesothelin mRNA and were not found in hens with tumors that did not express mesothelin (n = 0/5) or normal ovaries (n = 0/5).

Conclusion

The results support the utility of the hen as a novel model for preclinical studies of mesothelin as a biomarker and a target for immunotherapy.

Sphingosine-1 phosphate receptor (S1p1), a critical receptor controlling human lymphocyte trafficking, is expressed in hen and human ovaries and ovarian tumors

Background

Sphingosine-1 receptor 1 (S1P1) plays a major role in regulating lymphocyte egress from peripheral lymph tissue. Lymphocyte trafficking is potentially a critical response to tumors and to tumor vaccines. Also, the receptor has been shown to influence metastasis. However, there is little information on its expression in the aged ovary or ovarian tumors. As a basis for further studies in the laying hen model of spontaneous ovarian cancer, the objective of this study was to determine if S1P1 is expressed in hens, and if the morphological distribution of S1P1 is similar in hen and human ovary and ovarian tumors.

Methods

S1P1 mRNA was ascertained in hen tissue by RT-PCR using hen specific primers. S1P1 protein expression and localization was evaluated in hen and human tissue with a human S1P1 antibody by Western blot and immunohistochemistry.

Results

S1P1 mRNA was expressed in all hen tissues examined. Protein was detected in human and hen ovary and ovarian tumors at 47, 72 and 108 kDa in Western blots. S1P1 was similarly expressed on endothelial cells, lymphocytes and surface epithelial cells in normal ovaries and tumor-containing ovaries of the hen. In addition, S1P1 distribution was heterogeneous in both hen and human ovarian tumors by immunohistochemistry.

Conclusion

The results show that S1P1 is expressed in the hen and human ovary as well as in ovarian tumors. These findings support the use of the hen in further studies of the role of S1P1 in metastasis and immune cell trafficking in ovarian tumor development.

Autoantigens in ovarian autoimmunity associated with unexplained infertility and premature ovarian failure

OBJECTIVE

To identify ovarian autoantigens associated with ovarian autoantibodies.

DESIGN

Hypothesis-generating prospective study.

SETTING

Urban infertility referral centers and academic research institution.

PATIENT(S)

Seventy-four patients with infertility, 19 patients with premature ovarian failure (POF), and 16 healthy control women.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Identification of autoantigens.

RESULT(S)

To identify major antigens for ovarian autoimmunity, sera from 74 women with unexplained infertility were screened for ovarian autoantibodies (AOAs) by immunoassay and one-dimensional Western blot. The majority of sera had immunoreactions at 50-56 kDa. Six representative positive infertility sera were used to identify antigens between 40 and 60 kD by two-dimensional Western blot and mass spectrometry. Antigens included aldehyde (retinal) dehydrogenases (ALDH1A1, ALDH1A2, and ALDH7A1), protein disulfide isomerase A3, vimentin, α-enolase, phosphoglycerate dehydrogenase, and selenium-binding protein 1 (SBP1). Sixty percent (24 out of 40) of infertility and POF sera were positive for recombinant ALDH1A1, SBP1, or enolase; 80.7% (21 out of 26) of AOA-positive sera had antibodies to one or more of the three antigens, and only 7% (1 out of 14) of AOA-negative sera had antibodies to recombinant proteins.

CONCLUSION(S)

ALDH1A1 and SBP1 are unique to ovarian autoimmunity associated with infertility and POF, and may provide the basis for specific tests to identify patients with ovarian autoimmunity.