Increased chemotactic activity of peritoneal fluid in patients with endometriosis

Combinatory effects of current regimens and Guizhi Fuling Wan on the development of endometriosis

OBJECTIVE

Endometriosis, defined as the growth of endometrial glands and stromal cells in a heterotopic location under the cyclic influence of ovarian hormones, is a common gynecological disorder manifested by chronic pelvic pain and infertility. In traditional Chinese medicine, endometriosis is characterized by stagnation of vital energy (qi) and blood stasis. Guizhi Fuling Wan (GFW) was first described in Chinese canonical medicine to treat disorders associated with stagnation of qi and blood stasis, including endometriosis. Therefore, the current study aimed to test the effects of combining GFW with western medicine on the suppression of endometriosis.

MATERIALS AND METHODS

Endometriosis was generated by suturing endometrial tissue on the peritoneal wall of C57BL/6JNarl mice. The mice were subsequently treated with either GFW or current hormonal therapies or in combination for 28 days.

RESULTS

Endometriosis development was inhibited by GFW, Gestrinone, Visanne, GFW + Gestrinone or GFW + medroxyprogesterone acetate (MPA). The expression of intercellular adhesion molecule 1 (ICAM-1) was inhibited by GFW, Gestrinone, MPA, Visanne, GFW + Gestrinone, GFW + MPA and GFW + Visanne. Vascular endothelial growth factor (VEGF) expression was inhibited by GFW, Gestrinone, Visanne, GFW + Gestrinone and GFW + MPA. Both ICAM-1- and VEGF-reducing effects of GFW were attenuated by western medicines. Administration of GFW, MPA, Visanne, GFW + MPA and GFW + Visanne also correspondingly reduced macrophage population in peritoneal fluid. GFW, MPA, Visanne, GFW + MPA and GFW + Visanne enhanced B-cell population in peritoneal fluid.

CONCLUSION

The current study reveals the therapeutic effects of GFW on endometriosis. However, the combination of GFW and current hormonal therapies potentially impedes the efficacy of each individual agent in treating endometriosis.

Leflunomide—an Immunomodulator—Induces Regression of Endometrial Explants in a Rat Model of Endometriosis

OBJECTIVE

To test if leflunomide, an immunomodulator, could impede the growth of an ectopic uterine tissue.

METHODS

Endometriosis was surgically induced in 26 rats by transplanting an autologous fragment of endometrial tissue onto the inner surface of the abdominal wall. Four weeks later two rats were killed. The volume and weight of the implants were measured. The remaining rats were randomly grouped, and in group 1 no medication was given. To the rats in group 2, 35 mg/kg/d of leflunomide was administered orally. Four weeks later, rats were killed and ectopic uterine tissues were reevaluated morphologically and histologically. A scoring system was used to evaluate preservation of epithelia.

RESULTS

Two rats in the control group died 5 weeks after surgery. There was a significant difference in post-treatment spherical volumes (139.1 +/- 92.8 versus 33.5 +/- 12.5 mm3) and explant weights (156.3 +/- 105.6 versus 38.6 +/- 12.6 mg) between the control and leflunomide-treated groups. The epithelia were found to be preserved significantly better in the control group when compared with the leflunomide-treated group (median 2.5 [interquartile range, 1.25] versus median 1.00 [interquartile range, 1.5]).

CONCLUSION

Leflunomide appeared to cause regression of experimental endometriosis in rats.

Pathogenesis of Endometriosis: Roles of Retinoids and Inflammatory Pathways

Endometriosis is a nonmalignant, but potentially metastatic, gynecological condition manifested by the extrauterine growth of inflammatory endometrial implants. Ten percent of reproductive-age women are affected and commonly suffer pelvic pain and/or infertility. The theories of endometriosis histogenesis remain controversial, but retrograde menstruation and metaplasia each infer mechanisms that explain the immune cell responses observed around the ectopic lesions. Recent findings from our laboratories and others suggest that retinoic acid metabolism and action are fundamentally flawed in endometriotic tissues and even generically in women with endometriosis. The focus of our ongoing research is to develop medical therapies as adjuvants or alternatives to the surgical excision of these lesions. On the basis of concepts put forward in this review, we predict that the pharmacological actions and anticipated low side-effect profiles of retinoid supplementation might provide a new treatment option for the long-term management of this chronic and debilitating gynecological disease.

Endometriosis: hormone regulation and clinical consequences of chemotaxis and apoptosis

BACKGROUND

The recruitment of immune cells by chemokines and the regulation of endometrial cell apoptosis are critical aspects of endometriosis biology. Here, we review the local (paracrine) and systemic hormone (endocrine) modulation of these two specific, but highly related phenomena.

METHODS

We searched Pubmed for items published in English between September 1991 and September 2011 and selected the studies evaluating the effects of hormones on chemokines or apoptosis in normal human endometrium and endometriosis.

RESULTS

Estradiol has proinflammatory and antiapoptotic effects in endometrial cells, and these effects appear to be exacerbated in women with endometriosis. In these women, physiological estradiol concentrations are able to induce an enhanced inflammatory response mediated by local chemokine production and to reinforce mechanisms of cell survival mediated by extracellular signal-regulated kinases and Bcl-2. The main effect of progestogens is to inhibit interleukin-8 and other chemokines in stromal cells from both eutopic and ectopic endometrium. Progesterone is also effective in inducing apoptosis in endometrial and endometriotic cells through the inhibition of Bcl-2 and nuclear factor-κB.

CONCLUSIONS

Estrogens and progestogens modulate chemotaxis and apoptosis in human endometrium and endometriotic cells and tissues. These endocrine and paracrine pathways are perturbed in women with endometriosis, contributing to inflammatory responses, abnormal tissue remodeling, therapeutic refractoriness and disease persistence. Ultimately, they promote adhesion formation and the clinical symptoms of pelvic pain and infertility. A more detailed understanding of the molecular mechanisms involved will offer new opportunities for novel pharmacological strategies to diagnose and treat endometriosis.

Peritoneal fluid from endometriosis patients switches differentiation of monocytes from dendritic cells to macrophages

Immunological abnormalities of cell-mediated and humoral immunity might be associated with the pathogenesis of endometriosis. This study has examined the effects of peritoneal fluid obtained from patients with endometriosis (ePF) on the phenotypic characteristics of macrophages and dendritic cells (DCs) derived from monocytes. Monocytes were obtained from healthy young volunteers and cultured with ePF (n=12) or a control PF (cPF) (n=5) in the presence or absence of macrophage-colony stimulating factor (M-CSF) or IL-4 plus granulocyte macrophage-colony stimulating factor (GM-CSF). The ePF was demonstrated to increase expression levels of CD14 and CD64 on isolated monocytes in the presence or absence of M-CSF. Compared with cPF, addition of 10% ePF to GM-CSF plus IL-4-treated monocytes significantly down-regulated CD1a expression and up-regulated CD64 expression, but did not enhance expression levels of class II MHC. ePF had no effect, however, on tumor necrosis factor-alpha-induced maturation of DC. Levels of IL-6, IL-10 and M-CSF production were higher in ePF-treated than cPF-treated monocytes for both cell culture conditions with GM-CSF plus IL-4 and M-CSF. A neutralizing IL-6 antibody, but not an IL-10 antibody, abrogated the ePF-induced down-regulation of CD1a, up-regulation of CD64 and secretion of M-CSF. These results suggest that ePF favorably induces monocyte differentiation toward macrophages rather than DCs, and that this effect is mediated by IL-6. A reciprocal mode of cell differentiation between macrophages and DCs in response to ePF may be related to the pathogenesis of endometriosis.

The G(-2518)A polymorphism of monocyte chemotactic protein-1 (MCP-1) and its serum and peritoneal fluid levels in Korean women with endometriosis

OBJECTIVES

To investigate the associations between endometriosis and the G(-2518)A polymorphism of monocyte chemotactic protein-1 (MCP-1), and serum and peritoneal fluid MCP-1 levels in Korean women.

STUDY DESIGN

The G(-2518)A polymorphism of MCP-1 was analyzed by restriction fragment length polymorphism in 105 women with and in 101 women without endometriosis. Serum and peritoneal fluid MCP-1 levels were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The genotype frequencies of the MCP-1 G (-2518)A polymorphism were GG 36.9%, AG 52.9%, and AA 10.2%. MCP-1 genotype frequencies and serum and peritoneal fluid MCP-1 levels were similar in those with or without endometriosis and were not dependent on disease stage. A significant correlation was found between serum and peritoneal fluid levels of MCP-1. However, no differences were found between MCP-1 genotypes in terms of serum and peritoneal fluid MCP-1 levels.

CONCLUSIONS

Serum and peritoneal fluid MCP-1 levels and the G (-2518)A MCP-1 polymorphism were found not to be associated with endometriosis in Korean women.

Effects of peritoneal fluid from endometriosis patients on the release of vascular endothelial growth factor by neutrophils and monocytes

BACKGROUND

An increase in the level of the vascular endothelial growth factor (VEGF) production has been reported in the peritoneal fluid (PF) of endometriosis patients. This suggests that changes in the vascular permeability and angiogenesis play an important role in the pathophysiology of this disease. This study examined the effects of the PF obtained from endometriosis patients on the release of VEGF by neutrophils and monocytes.

METHODS

Neutrophils and monocytes were obtained from young healthy volunteers and cultured with the PF obtained from either endometriosis patients (EPF) (n=18) or a control group (CPF) (n=4). A human monocyte/macrophage cell line, THP-1, was cultured with either 10% EPF or 10% CPF. The PF and culture supernatants were assayed for VEGF using ELISA. Real-time PCR and Western blotting were used to measure the VEGF mRNA and protein expression level, respectively.

RESULTS

The VEGF levels were higher in the EPF than in the CPF (591+/-75 versus 185+/-31 pg/ml, P<0.05). However, the level of VEGF released by THP-1 cells in CPF and EPF was similar. The EPF induced the release of VEGF by neutrophils, but no VEGF was released by monocytes. The VEGF mRNA expression levels in the neutrophils were higher in the EPF, which was abrogated by cycloheximide, suggesting that the EPF induces the production of VEGF in neutrophils. Neutralizing antibodies against IL-8 and TNF-alpha did not completely prevent the EPF-induced release of VEGF by the neutrophils, even though these growth factors stimulated the release of VEGF by neutrophils. There was a positive correlation between the VEGF and IL-10 concentrations in the EPF (correlation coefficient=0.549, P=0.012, n=18), but the neutralizing antibody of IL-10 did not affect the release of VEGF by the EPF-treated neutrophils.

CONCLUSION

The EPF induced the production and release of VEGF by neutrophils, suggesting that neutrophils may be a source of peritoneal VEGF. In addition, neutrophil-derived VEGF might be a marker for diagnosing endometriosis.

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.

Expression of matrix metalloproteinases in ovarian endometriomas: immunohistochemical study and enzyme immunoassay

Like carcinoma, endometriosis has the unique characteristics, of invasion and metastasis, though pathologically, it is a benign tumor. However, the mechanism of destruction of the surrounding tissue in endometriosis is still unclear. In this study, the expression and localization of matrix metalloproteinases (MMP)-1, -2, -3, -7, -9 and tissue inhibitors of metalloproteinases-1 (TIMP-1) were evaluated by immunohistochemistry for 20 cases and the amounts of MMP-1, TIMP-1 and MMP-1/TIMP-1 complex in the fluid of endometrioma, were analyzed by ELISA and western blotting for 20 cases, which were analyzed by immunohistochemical study. MMP-1, -2 and -9 were detected strongly in both stromal and epithelial cells and MMP-7 in the epithelial cells in the menstrual period. MMP-3 was mainly expressed in macrophage containing hemosiderin but the change of expression was not clear. TIMP-1 was intensively detected in both stromal and epithelial cells in the menstrual period but the expression decreased in other stages of the menstrual cycle. ELISA for MMP-1 also showed results similar to immunohistochemistry, suggesting that it was released to the cyst in the menstrual period when it was released to the extracellular space from the cytoplasm. The expression of TIMP-1 was not clearly changed during the menstrual cycle. From these results, it was suggested that the destruction of the surrounding matrix by endometriosis might be caused by various MMPs, which are mainly produced in stromal cells.

Signal transduction pathways involved in macrophage migration induced by peritoneal fluid chemotactic factors in stages I and II endometriosis

OBJECTIVE

To explore the role of G-protein coupled signaling pathways in activation of macrophage migration in endometriosis stages I and II.

DESIGN

Case controlled study.

SETTING

University hospital.

PATIENT(S)

Fifteen patients undergoing laparoscopy for elective sterilization (n = 5) or for diagnosis of endometriosis stages I and II associated with infertility (n = 10).

INTERVENTION(S)

Peritoneal fluid samples were collected during laparoscopy.

MAIN OUTCOME MEASURE(S)

Macrophage migration induced by peritoneal fluid from patients with endometriosis stages I and II (PF SI-II) and potential G-protein coupled receptors and second messengers involved in macrophage activation.

RESULT(S)

Potential G-protein coupled receptors and second messengers involved in macrophage activation were evaluated after incubation of U-937 cells differentiated into macrophages with inhibitors of phospholipase A and C, adenylate cyclase, and protein kinase A and C. Macrophage chemotactic activity induced by PF SI-II was inhibited in the presence of a phospholipase C and A2 inhibitor (IC50= 30 microM) and after treatment with myristoylated protein kinase C peptide inhibitor (50 nM). An increase in inositol phosphate (IP3) was also observed in macrophages exposed to PF SI-II. Activation of multiple G-proteins in macrophages was examined after exposure of cells to PF SI-II in the presence and absence of Bordettela pertussis and cholera toxins. No effect on macrophage migration was observed.

CONCLUSION(S)

Macrophage chemotaxis induced by PF SI-II appears to involve activation of pertussis toxin-insensitive G-protein coupled receptors in macrophages. Our data suggest that these events lead to subsequent activation of phospholipases followed by generation of IP3 and potential mobilization of intracellular Ca2+. Subsequent phosphorylation of target proteins by protein kinase C may regulate the chemotactic responses. The adenylate cyclase pathway does not appear to play a role in this process.

Uterine chemokines in reproductive physiology and pathology

PROBLEM

Chemokines are increasingly recognized as important regulators of uterine function.

METHODS OF STUDY

The following is a review of uterine chemokines, especially monocyte chemotactic protein (MCP)-1, interleukin (IL)-8, and regulated-upon-activation normal-T-cell-expressed and -secreted (RANTES) protein, in reproductive physiology and pathology.

RESULTS

It is increasingly clear that IL-8, MCP-1, RANTES and their receptors are produced by endometrial, myometrial, and trophoblast cell types in a timed and co-ordinated manner. In addition to the regulation of leukocyte migration and function, uterine chemokines also display specific roles in endometrial angiogenesis, apoptosis, proliferation, and differentiation. IL-8, MCP-1 and RANTES are regulated by local growth factors and cytokines such as tumor necrosis factor-alpha (TNF-alpha), interferon-gamma, and IL-1. IL-8 takes part in cervical ripening and parturition. IL-8, MCP-1 and RANTES are also found at high levels in the peritoneal fluid of women with endometriosis.

CONCLUSION

Co-ordination of chemokine-chemokine receptor interactions plays an important role in the menstrual cycle and successful pregnancy. Moreover, unbalanced chemokine expression contributes to pathologic conditions typified by uncontrolled cellular proliferation, migration and invasion.

Modulation of neutrophil apoptosis by plasma and peritoneal fluid from patients with advanced endometriosis

BACKGROUND

The increased production of pro-inflammatory chemoattractant cytokines for neutrophils in endometriosis suggests that changes in the immune system play an important role in the pathophysiology of endometriosis. The effects of plasma and peritoneal fluid from patients with advanced endometriosis on the apoptosis of neutrophils were investigated.

METHODS

Apoptotic changes of neutrophils were evaluated by morphological changes using Giemsa staining. Apoptosis was confirmed by DNA electrophoretic analysis.

RESULTS

Compared with the plasma (n = 20) and peritoneal fluid (n = 5) of healthy controls, the addition of 10% plasma (n = 20) and peritoneal fluid (n = 10) from patients with endometriosis to an in-vitro culture of neutrophils from healthy subjects reduced the percentage of apoptotic cells from 65.3 +/- 6.6 to 27.2 +/- 4.6% (P < 0.001) and from 45.3 +/- 4.8 to 10.5 +/- 4.3% (P < 0.001) respectively. Neutralizing interleukin-8 antibody abrogated the delay of neutrophil apoptosis induced by peritoneal fluid, but not in the plasma of endometriosis patients.

CONCLUSIONS

These findings show that interleukin-8 is one of the neutrophil survival factors in the peritoneal fluid of endometriosis patients and that an unidentified survival factor is also present in the plasma of patients with endometriosis.

The fallopian tube and reproductive health

The fallopian tube is the essential link between the ovary and the uterus. Its transport mechanisms are now reasonably well understood and include orderly ovum transfer by the fimbria, and ovum/preembryo retention, with transport to the uterus on the third postovulatory day. Sperm/tube interaction ensures a reservoir and storage/activation system at the tubal isthmus. Ovum/tube interaction is driven by the HCO3 ion in the tubal secretions, which also supply pyruvate and other essential substances to the preembryo. Tubal function may be impaired/destroyed by salpingitis, a peritubal disease resulting from ruptured appendix, endometriosis, and ectopic pregnancy (often the result of prior tubal damage with partial occlusion or luminal adhesions). Prophylactic measures include counseling the patient on how to avoid sexually transmitted disease or inhibition of upward ascent of bacteria, and, in the case of ectopic pregnancy, how to use the most efficient contraceptive measures. The least intrusive transfer methods are helpful in avoiding tubal pregnancy following embryo transfer after in vitro fertilization, and results are improved by pretreatment removal of hydrosalpinges. Among adolescents, efforts should be made to preserve tubal function and to increase awareness of the importance of avoiding tubal disease with an eye to preserving future reproductive capacity.

Chemokines and human reproduction

OBJECTIVE

To review the available information regarding chemotactic cytokines and their possible implications in human reproduction.

DESIGN

A thorough literature and MEDLINE search was conducted to identify studies relating to the role of chemokines in ovulation, menstruation, implantation, cervical ripening and preterm labor, and endometriosis.

RESULT(S)

Chemokines mediate leukocyte traffic through their specific receptors in various tissues. Although four families have been described to date, two remain the major subfamilies: alpha-chemokines (with interleukin-8 as representative for this group), and beta-chemokines (with monocyte chemotactic protein-1 as representative). Interleukin-8, monocyte chemotactic protein-1, and growth-regulated oncogene-alpha are involved in follicular development and atresia, ovulation, steroidogenesis, and corpus luteum function. Interleukin-8 showed cycle-dependent expression in human endometrium, and at the same time, stimulated endometrial stromal cell growth, acting as an autocrine growth factor. Interleukin-8 has been identified in human amnion, chorion, decidua, and villous placenta, and its level increases during labor. Levels of interleukin-8 correlate with the release of collagenases, a crucial step that regulates the process of cervical extracellular matrix remodeling. The levels of monocyte chemotactic protein-1; regulated on activation, normal T-expressed and secreted (RANTES); interleukin-8; and growth-regulated oncogene-alpha are elevated in the peritoneal fluid of women with endometriosis, and they correlate with the stage of the disease.

CONCLUSION(S)

Chemokines play a relevant role in many physiologic and pathologic situations, such as ovulation, menstruation, implantation, cervical ripening and preterm labor, and endometriosis. Their regulation soon may provide new therapeutic strategies.

Potential implications of chemokines in reproductive function: an attractive idea

Chemokines are a new family of cytokines specialised in attracting leukocytes, acting in physiological conditions and in pathological processes. A wide variety of cell types in response to exogenous irritants or endogenous mediators of the inflammatory reaction produce them. Pivotal parts of reproductive function are based on inflammatory like processes wherein different leukocytes subsets are recruited and activated to produce paracrine autocrine effects in which cytokines and growth factors are implicated. Since chemokines control leukocyte trafficking and belong to the cytokine superfamily, in this review we analyze the implications of these molecules and related cells in ovulation, embryonic implantation, menstruation, parturition and their role in pathological process such as preterm delivery, endometriosis, ovarian hyperstimulation syndrome and HIV infection.

Macrophage scavenger receptor(s) and oxidatively modified proteins in endometriosis

OBJECTIVE

To determine whether cultured human peritoneal macrophages have functional scavenger receptor(s) and whether activation of macrophages in endometriosis may involve an increase in scavenger receptor activity.

DESIGN

A controlled clinical study comparing peritoneal fluid (PF) macrophages of women with endometriosis and controls without endometriosis.

SETTING

Women undergoing laparoscopic evaluation and treatment in a tertiary medical center.

PATIENT(S)

Twenty-one women undergoing evaluation for pelvic pain or infertility and 10 women undergoing elective laparoscopic tubal ligation.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Evidence for functional macrophage scavenger receptor and evidence of ligands for the scavenger receptor in PF.

RESULT(S)

Peritoneal macrophages of women with endometriosis degrade significantly more endothelial cell-low density lipoprotein (EC-LDL) and copper-oxidized LDL (Cu-LDL) than native LDL. Macrophages of women with endometriosis also incorporate more labeled oleic acid into cholesteryl ester in the presence of oxidized LDL (Ox-LDL) than in the presence of native LDL. Western blot analysis demonstrates the presence of adducts between lipid peroxidation products and proteins in PF of patients with and without endometriosis. The PF of women with endometriosis competes with labeled Ox-LDL for uptake by mouse peritoneal macrophages in a dose-dependent manner.

CONCLUSION(S)

We demonstrate for the first time that human macrophages have functional scavenger receptor(s) and that activation of macrophages in endometriosis involves an increase in scavenger receptor activity. Two lines of evidence indicate the presence of ligands for the scavenger receptor in PF.

Angiogenesis and macrophage activation in endometriosis

Recent studies suggest that the symptoms associated with endometriosis are the result of local peritoneal inflammation. Increased concentrations of activated pelvic macrophages and lymphocytes and the elevated levels of specific cytokines and growth factors reviewed above support this hypothesis. The precise roles of these soluble factors are currently unknown, but we propose that a complex network of endometrial cytokines are normally regulated by hormones produced during the ovulatory cycle. Ectopic endometrial implants also are subject to these same endocrine cues. The secretion of these proinflammatory proteins by endometriosis lesions into the peritoneal microenvironment appears to cause a recruitment of capillaries and activated inflammatory cells to the implant. Future therapeutic strategies directed to ameliorate the inflammatory reaction associated with endometriosis should not ignore the likely physiological actions of many of the same bioactive molecules in normal eutopic endometrial function.

Monocyte chemotactic protein-1 concentration in peritoneal fluid of women with endometriosis and its modulation of expression in mesothelial cells

OBJECTIVE

To investigate monocyte chemotactic protein-1 concentrations in the peritoneal fluid (PF) of women with or without endometriosis, then assess peritoneal mesothelial cells as a potential source of monocyte chemotactic protein-1.

DESIGN

Prospective study.

SETTING

University medical center.

PATIENT(S)

Women with (n = 60) or without (n = 18) endometriosis.

INTERVENTION(S)

First monocyte chemotactic protein-1 levels in PF were measured, then mesothelial cells in culture were treated with cytokines.

MAIN OUTCOME MEASURE(S)

In PF and culture supernatants, monocyte chemotactic protein-1 was measured by ELISA. In vitro monocyte chemotactic protein-1 messenger RNA expression was evaluated by Northern analysis.

RESULT(S)

The median concentration of monocyte chemotactic protein-1 in PF of control women was 137 pg/mL (conversion factor to SI unit, 0.115; range, 12 to 418 pg/mL); that of women with moderate endometriosis was 205 pg/mL (range 65 to 6,000 pg/mL); and that of those with severe endometriosis was 1,165 pg/mL (0 to 2,602 pg/mL). Within the moderate to severe endometriosis group, monocyte chemotactic protein-1 levels were higher in women with untreated endometriosis (354 pg/mL range 0 to 6,000 pg/mL) than in women receiving GnRH agonist (128 pg/mL, range 0 to 216 pg/mL). In the control group, monocyte chemotactic protein-1 levels were higher in the proliferative phase than in the secretory phase. Mesothelial cells produced constitutively monocyte chemotactic protein-1; moreover, both interleukin-1 alpha and tumor necrosis factor-alpha induced higher levels of monocyte chemotactic protein-1.

CONCLUSION(S)

Levels of monocyte chemotactic protein-1 in PF were higher during the proliferative phase than secretory phase of control women and increased in moderate to severe endometriosis. The regulated expression of monocyte chemotactic protein-1 may recruit macrophages into PF and contribute to the pathogenesis of endometriosis.

Basic research in endometriosis

A more thorough understanding of the mechanisms associated with the cause and pathophysiology of endometriosis may help in the development of new diagnostic and therapeutic methods for the management of endometriosis. Research has begun to enhance our understanding of endometriosis by demonstrating the differences and similarites between eutopic and ectopic endometrium, and by characterizing the peritoneal environment. Animal models have been developed and validated to conduct studies that are ethically impossible in women. Recently, cell culture models, using purified populations of cells from endometriotic lesions, have provided an appropriate in vitro endometriosis model to study the language by which cells communicate; to evaluate the biochemical effects of steroids, growth factors, pharmacological agents and immunomodulatory agents on the cells; and to study the effects of endometriosis on reproduction.

Chemotaxis of macrophages by a peritoneal fluid protein in women with endometriosis

OBJECTIVE

To expand on a preliminary study comparing the chemotactic potential of peritoneal fluid (PF) from women with and without endometriosis and to characterize this activity via immunosuppressants and a protease.

DESIGN

Case control study.

SETTING

University center.

PATIENT(S)

Fifty-nine women with endometriosis and 44 without, undergoing laparoscopy.

INTERVENTION(S)

Collection of PF, endometriotic, ovarian, and endometrial biopsies at laparoscopy.

MAIN OUTCOME MEASURE(S)

Chemotactic activity of PF was tested via an in vitro assay alone and in the presence of immunosuppressants cyclosporin A (CSA), FK506, rapamycin, and type XVII-b(S-V8) protease and in media incubated with endometriotic, ovarian, or endometrial biopsy specimens.

RESULT(S)

The PF from women with endometriosis had significantly greater chemotactic activity (cells per well, mean +/- SD) than without endometriosis (142 +/- 39 versus 48 +/- 17). Cyclosporin A significantly inhibited the chemotactic activity of the endometriotic PF; FK506 and rapamycin did not. Incubation of media with endometriotic tissue, but not ovarian or endometrial, for > or = 7 hours displayed chemotactic activity. Protease type XVII-b(S-V8) added to endometriotic PF inhibited this chemotactic activity.

CONCLUSION(S)

Peritoneal fluid from patients with endometriosis contains a protein chemotactic factor attracting inflammatory cells into the peritoneal cavity, possibly secreted by endometriotic implants. This chemotactic factor may be a member of the immunophilin family because of its inhibition profile.

Increased monocyte chemotactic protein-1 level and activity in the peripheral blood of women with endometriosis. Le Groupe d'Investigation en Gynécologie

OBJECTIVE

Our purpose was to evaluate monocyte chemotactic protein-1 in the peripheral blood of women with and without endometriosis.

STUDY DESIGN

Fifty-seven patients with endometriosis at laparoscopy done for infertility and pelvic pain were compared with 44 fertile women with no evidence of endometriosis at tubal ligation by laparoscopy. Monocyte chemotactic protein-1 concentration in the plasma was determined by enzyme-linked immunosorbent assay and its biologic activity was evaluated by measuring monocyte chemotaxis with use of a human histiocytic cell line (U937).

RESULTS

Monocyte chemotactic protein-1 concentrations (median and range of values) found in the plasma were higher in patients with endometriosis (163, 0 to 788 pg/ml) than in normal controls (0, 0 to 355 pg/ml). This elevation was significant only in the minimal stage of endometriosis (revised American Fertility Society stage I). However, increased chemotactic activity (mean number of migrating cells/mm2 +/- SEM) was found in the stages I (1240 +/- 141), II (519 +/- 30), and III-IV (523 +/- 23) of the disease compared with normal controls (205 +/- 20). A total of 35% to 44% of this activity was inhibited in the presence of an antibody specific to monocyte chemotactic protein-1.

CONCLUSION

Endometriosis is associated with increased level and activity of monocyte chemotactic protein-1 in the peripheral blood. The elevation and activation of this cytokine could play a relevant role in the immunoinflammatory process associated with the disease.

Secretion of monocyte chemotactic protein-1 by cytokine-stimulated endometrial cells of women with endometriosis. Le groupe d'investigation en gynécologie

OBJECTIVE

To evaluate in vitro the production of monocyte chemotactic protein-1 (MCP-1) by endometrial cells of patients with and without endometriosis.

DESIGN

Primary cultures of stromal and epithelial cells isolated from human endometrium were exposed during 24 hours to different cytokines. Monocyte chemotactic protein-1 secretion was analyzed in the culture medium.

SETTING

Gynecology clinic and laboratories of endocrinology of reproduction and immunology.

PATIENTS

Women presenting for infertility or pelvic pain in which endometriosis was diagnosed at laparoscopy (n = 6) and women presenting for tubal ligation without laparoscopic evidence of the disease (n = 6).

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

De novo secretion of MCP-1 in the culture supernatant by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis after metabolic labeling with 35S-cysteine.

RESULTS

The incubation of endometrial epithelial cells of endometriosis women with either interleukin-1 beta or tumor necrosis factor-alpha resulted in the appearance of at least two and sometimes three bands having approximately 15, 13, and 9 kd molecular weights. These bands were identified as three distinct species of MCP-1 as their immunoprecipitation was prevented effectively in presence of an excess of cold MCP-1. In contrast, the endometrial epithelial cells of only one of six normal women produce significant levels of MCP-1 under the same stimulation conditions. The stromal cells of both groups of subjects do not secrete appreciable amounts of MCP-1 or only small quantities in two cases of endometriosis.

CONCLUSIONS

Monocyte chemotactic protein-1 secretion is upregulated in cytokine-stimulated endometrial epithelial cells of women having endometriosis as compared with normal women without evidence of the disease. Such a difference at the level of eutopic endometrial cell may have a significance in the physiopathology of endometriosis.

Cytokine-induced secretion of monocyte chemotactic protein-1 by human endometriotic cells in culture. The Groupe d'Investigation en Gynécologie

OBJECTIVE

Local secretion of chemotactic factors could contribute to the attraction of macrophages into the peritoneal cavity of women with endometriosis. The purpose of this study was to investigate the ability of endometriotic cells to produce monocyte chemotactic and activating protein-1 in response to interleukin-1 beta and tumor necrosis factor-alpha, which are found in elevated levels in the peritoneal fluid of patients with endometriosis.

STUDY DESIGN

Cultures of fibroblast-like and epithelial cells isolated from endometriotic tissue were incubated with different concentrations of cytokines for varying periods of time. The de novo secretion of monocyte chemotactic protein-1 in the culture supernatants was analyzed by immunoprecipitation and electrophoresis after metabolic labeling with sulfur 35-labeled cysteine.

RESULTS

The incubation of endometriotic fibroblast-like cells with interleukin-1 beta and tumor necrosis factor-alpha resulted in a time- and dose-dependent release of monocyte chemotactic protein-1 into the culture supernatant. Coincubation of the cells with tumor necrosis factor-alpha and interferon gamma resulted in a synergistic and dose-dependent increase of the monocyte chemotactic protein-1 secretion, whereas interferon gamma alone had no significant effect. Preliminary results indicate that monocyte chemotactic protein-1 is also produced by endometriotic epithelial cells in response to the same cytokines.

CONCLUSIONS

Cytokine-stimulated endometriotic cells synthesize and secrete monocyte chemotactic protein-1 in culture, and they may play a relevant role in the recruitment of macrophages to the peritoneal cavity of patients by the local production of chemotactic factors.

Immunohistochemical localization of granulocyte-macrophage colony-stimulating factor in matched endometriosis and endometrial tissues

OBJECTIVE

Murine endometrial granulocyte-macrophage colony-stimulating factor has been related to macrophage recruitment and activation and postulated to mediate reproductive events. This study was designed to determine whether granulocyte-macrophage colony-stimulating factor is present in normal human endometrium or endometriosis.

STUDY DESIGN

Granulocyte-macrophage colony-stimulating factor was immunohistochemically evaluated in matched endometrial and endometriosis biopsy specimens (n = 19) and endometrial biopsy specimens from disease-free patients (n = 8). Staining differences were determined with McNemar's, Fisher's, and Wilcoxon's tests.

RESULTS

Granulocyte-macrophage colony-stimulating factor was primarily localized in endometrial and endometriotic epithelial cells. Expression (p = 0.71) and staining intensity (p = 0.37) was similar in matched proliferative-phase endometrium and endometriosis. Matched secretory-phase endometrium and endometriosis also expressed granulocyte-macrophage colony-stimulating factor in similar proportions (p = 0.12), but staining intensity was enhanced in secretory endometriosis compared with secretory endometrium (p = 0.05). Endometrial granulocyte-macrophage colony-stimulating factor did not vary throughout the menstrual cycle, but endometriotic expression (p = 0.013) and staining intensity (p = 0.008) were significantly greater in the secretory phase.

CONCLUSIONS

Granulocyte-macrophage colony-stimulating factor is localized in endometrial and endometriotic epithelial cells with increased expression in secretory-phase endometriosis. Granulocyte-macrophage colony-stimulating factor may elicit migration, proliferation, and activation of endometrial and peritoneal macrophages.