Interleukin-12 and its free p40 subunit regulate immune recognition of endometrial cells: potential role in endometriosis

Association between gene polymorphisms of IL-12, IL-12 receptor and IL-27 and organ involvement in Iranian endometriosis patients

Endometriosis is an inflammatory disease characterized by the presence of ectopic endometrial tissue, immune cell dysfunction and abnormal cytokine secretion. In addition to immunological factors, genetic variations that influence endometriosis severity and cytokine expression levels play important roles in the pathogenesis of this disease. Interleukin-12 (IL-12), specifically its p40 subunit encoded by IL-12B gene and the interleukin-12 receptor β1 (IL-12Rβ2) chain of its receptor, as well as interleukin-27 (IL-27) are important in the establishment of endometriosis. So, in this study, we measured IL-12 and IL-27 serum levels and investigated the possible links between IL-12B rs3212227, IL-12Rβ2 rs3790565 and IL-27 rs153109 polymorphisms and the risk of developing endometriosis in a group of Iranian women. In this case-control study, 162 endometriosis patients and 151 healthy women were included and tested for the aforementioned polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The enzyme-linked immunosorbent assay (ELISA) method was also used to measure IL-12 and IL-27 serum levels. Although there was no statistically significant association between the genotypes and alleles of the studied polymorphisms and the development of endometriosis in general, the AA genotype of IL-12B rs3212227 showed a significant association with uterine endometriosis when compared to AC+CC genotypes (p = .04, CI = 0.270-0.988, OR = 0.517). Indeed, the AA genotype of the IL-12B rs3212227 single nucleotide polymorphism (SNP) may be linked with a lower risk of developing uterine endometriosis. There was no significant difference in IL-27 levels between the two studied groups (p = .49), and IL-12 levels were undetectable in both groups. In conclusion, the AA genotype of IL-12B rs3212227 might be associated with a decreased risk of uterine involvement in endometriosis patients.

NK Cells as Potential Targets for Immunotherapy in Endometriosis

Endometriosis is a common gynecological disease defined by the presence of endometrial-like tissue outside the uterus, most frequently on the pelvic viscera and ovaries, which is associated with pelvic pains and infertility. It is an inflammatory disorder with some features of autoimmunity. It is accepted that ectopic endometriotic tissue originates from endometrial cells exfoliated during menstruation and disseminating into the peritoneum by retrograde menstrual blood flow. It is assumed that the survival of endometriotic cells in the peritoneal cavity may be partially due to their abrogated elimination by natural killer (NK) cells. The decrease of NK cell cytotoxic activity in endometriosis is associated with an increased expression of some inhibitory NK cell receptors. It may be also related to the expression of human leukocyte antigen G (HLA-G), a ligand for inhibitory leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1) receptors. The downregulated cytotoxic activity of NK cells may be due to inhibitory cytokines present in the peritoneal milieu of patients with endometriosis. The role of NK cell receptors and their ligands in endometriosis is also confirmed by genetic association studies. Thus, endometriosis may be a subject of immunotherapy by blocking NK cell negative control checkpoints including inhibitory NK cell receptors. Immunotherapies with genetically modified NK cells also cannot be excluded.

Endometriosis-induced changes in regulatory T cells - insights towards developing permanent contraception

BACKGROUND

Endometriosis is a gynecological disorder that is associated with alterations in the immune system that contributes to its pathology as well as its associated infertility.

MAIN FINDINGS

This brief report summarizes our findings related to the changes in T regulatory cells (Tregs) that may affect the uterine environment and impact the fertility of women and nonhuman primates with endometriosis.

PRINCIPAL CONCLUSION

Targeted therapies that could reduce Tregs within the reproductive tract may have a potential as long-lasting or permanent contraception.

Effect of helixor A on natural killer cell activity in endometriosis

BACKGROUND AND AIM

NK cells are one of the major immune cells in endometriosis pathogenesis. While previous clinical studies have shown that helixor A to be an effective treatment for endometriosis, little is known about its mechanism of action, or its relationship with immune cells. The aim of this study is to investigate the effects of helixor A on Natural killer cell (NK cell) cytotoxicity in endometriosis

MATERIALS AND METHODS

We performed an experimental study. Samples of peritoneal fluid were obtained from January 2011 to December 2011 from 50 women with endometriosis and 50 women with other benign ovarian cysts (control). Peritoneal fluid of normal control group and endometriosis group was collected during laparoscopy. Baseline cytotoxicity levels of NK cells were measured with the peritoneal fluid of control group and endometriosis group. Next, cytotoxicity of NK cells was evaluated before and after treatment with helixor A. NK-cell activity was determined based upon the expression of CD107a, as an activation marker.

RESULTS

NK cells cytotoxicity was 79.38±2.13% in control cells, 75.55±2.89% in the control peritoneal fluid, 69.59±4.96% in endometriosis stage I/II endometriosis, and 63.88±5.75% in stage III/IV endometriosis. A significant difference in cytotoxicity was observed between the control cells and stage III/IV endometriosis, consistent with a significant decrease in the cytotoxicity of NK cells in advanced stages of endometriosis; these levels increased significantly after treatment with helixor A; 78.30% vs. 86.40% (p=0.003) in stage I/II endometriosis, and 73.67% vs. 84.54% (p=0.024) in stage III/IV. The percentage of cells expressing CD107a was increased significantly in each group after helixor A treatment; 0.59% vs. 1.10% (p=0.002) in stage I/II endometriosis, and 0.79% vs. 1.40% (p=0.014) in stage III/IV.

CONCLUSIONS

Helixor A directly influenced NK-cell cytotoxicity through direct induction of CD107a expression. Our results open new role of helixor A as an imune modulation therapy, or in combination with hormonal agents, for the treatment of endometriosis.

Interleukin-12 inhibits development of ectopic endometriotic tissues in peritoneal cavity via activation of NK cells in a murine endometriosis model

Involvement of impaired peritoneal immunosurveillance systems has been well established in the pathology of endometriosis. On the other hand, it has been observed that peritoneal administration of IL-12 suppress development of endometriotic lesions in a mouse endometriosis model. We investigated the effect of peritoneal administration of IL-12 on the peritoneal immunosurveillance system regarding NK cells in the mouse model. Treating the endometrial-tissue challenged mice with IL-12 for 5 consecutive days, from day -2 to day 2 (implantation of the endometrial tissues was done on day 0), cytotoxicity of splenic NK cells was enhanced immediately after the administration, on day 3, and development of the endometriotic lesions was reduced on day 21. In vivo NK cell depletion by administration of anti-IL-2Rβ mAb resulted in reduction of the cytotoxicity of splenic NK cells concomitant with a significant attenuation of suppressive effect of IL-12 on development of endometriotic lesions. Therefore, it was suggested that IL-12 suppresses development of endometriotic lesions via activation of NK cells, and that NK cells are involved in the primary defense for the development of endometriotic lesions.

Lactobacillus gasseri OLL2809 is effective especially on the menstrual pain and dysmenorrhea in endometriosis patients: randomized, double-blind, placebo-controlled study

In this study, we evaluated the efficacy of Lactobacillus gasseri OLL2809 on endometriosis by the randomized, double-blind and placebo-controlled clinical study, especially against pain, which is one of the causative factors to decrease the quality of life. Sixty-six patients clinically diagnosed with endometriosis were enrolled in this study, 62 of which have successfully completed the trial. The tablets containing 100 mg of L. gasseri OLL2809 (active tablet, n = 29) or placebo tablets (n = 33) were ingested once a day for 12 weeks. Visual analog scale (VAS) of pain intensity at the menstrual period and verbal rating scale (VRS) of dysmenorrhea were significantly improved by the ingestion of the active tablets as compared with placebo tablets. There was no significant change of blood examination and biochemical examination of blood in the enrolled patients. Above results show that the tablet containing L. gasseri OLL2809 is effective on endometriosis, especially against menstrual pain and dysmenorrhea. Moreover, it was found that the tablet has no adverse effects. Therefore, it was suggested that the tablet containing L. gaserri OLL2809 contributes to improve the quality of life in the patients with endometriosis.

The non-human primate model of endometriosis: research and implications for fecundity

The development of an animal model of endometriosis is crucial for the investigation of disease pathogenesis and therapeutic intervention. These models will enhance our ability to evaluate the causes for the subfertility associated with disease and provide a first-line validation of treatment modulators. Currently rodents and non-human primate models have been developed, but each model has their limitations. The aim of this manuscript is to summarize the current findings and theories on the development of endometriosis and disease progression and the effectiveness of therapeutic targets using the experimental induced model of endometriosis in the baboon (Papio anubis).

A baboon model for endometriosis: implications for fertility

Endometriosis is one of the most common causes of chronic pelvic pain and infertility in women in the reproductive age group. Although the existence of this disease has been known for over 100 years our current knowledge of its pathogenesis and the pathophysiology of its related infertility remains unclear. Several reasons contribute to our lack of knowledge, the most critical being the difficulty in carrying out objective long-term studies in women. Thus, we and others have developed a model of this disease in the non-human primate, the baboon (Papio anubis). Intraperitoneal inoculation of autologous menstrual endometrium results in the development of endometriotic lesions with gross morphological characteristics similar to those seen in the human. Multiple factors have been implicated in endometriosis-associated infertility. We have described aberrant levels of factors involved in multiple pathways important in the establishment of pregnancy, in the endometrium of baboons induced with endometriosis. Specifically, we have observed dysregulation of proteins involved in invasion, angiogenesis, methylation, cell growth, immunomodulation, and steroid hormone action. These data suggest that, in an induced model of endometriosis in the baboon, an increased angiogenic capacity, decreased apoptotic potential, progesterone resistance, estrogen hyper-responsiveness, and an inability to respond appropriately to embryonic signals contribute to the reduced fecundity associated with this disease.