Expression Of Macrophages And Interleukin 1β, 8 In Women With Endometriosis And Its Relation To Clinic Significance

BackgroundEndometriosis is one of the common gynecological diseases, affecting 10% of women in reproductive age. Recent years, the incidence of endometriosis is everlasting increasing. The characteristics of the pathologic changes in the lesions of this disease include abroad anatomical distributions, the diversity appearance, and the high invasiveness in residence tissue. The high recurrence rate of endometriosis cause it become a difficult curative disease. Though there were several theories represent to this disease, but the exact pathogenesis is still unknown. Sampson's theory of retrograde menstruation is the most widely accepted theory postulated to explain peritoneal endometriosis. But prevalence of retrograde menstruation does not correlate with the prevalence of endometriosis among women in reproductive age. It is clear that there must be other factors that contribute to the pathogenesis of this disease. Eutopic endometrium determination hypothesis appear in more and more literatures. This hypothesis indicates that the eutopic endometrium of women with endometriosis are innately abnormal and contribute to the establishment and maintenance of the disease. If refluxed endometrial cells can grow successfully in abdominal cavity, it must breakthrough three lines of host defensive mechanisms that are peritoneal fluid, macrophages and peritoneal ECM. I t must accomplished adhesion-invasion-angiogenesistrilogy.In recently years, there are emerging data from the different literatures present the immunological mechanisms hypotheses postulated to explain endometriosis. Macrophages are multifunctional cells play key roles in local immune response. Macrophages can execute diverse functional activities, including phagocytosis and degradation of foreign antigens, matrix dissolution and tissue remodelling, and production and secretion of cytokines, chemokines and growth factors. Macrophages are the first line of local host defense when menstrual debris reflux into peritoneal cavity. There are several evidence suggest that the changes of numbers and functions of macrophage both in peritoneal fluid and in eutopic and ectopic endometrium play a pivotal role in the establishment of the endometriotic implants. Khaleque investigated the distribution of macrophage infiltration in eutopic and ectopic endometrium throughout the menstrual cycle. They found that infiltration macrophages appeared to be higher in the endometrium in women with endometriosis than in those without endometriosis, and this was more marked in minor endometriosis. The eutopic endometrium in women with endometriosis appeared to harbor more macrophages in both the proliferative phase and secretory phase compared with control women. Macrophages infiltration in the endometrium increased steadily throughout the cycle of the endometrium . Several published reports suggested that the elevated numbers and activated function of macrophages in eutopic and ectopic endometrium, in peritoneal fluid (PF) of women with endometriosis play a core role in the pathologenesis of endometriosis. The function of antigen presentation and phagocytosis of activated macrophages are reduced and the secrectory functions are imposed. Activated macrophages may release products such as cytokines, prostaglandins (PGs), complement components and hydrolytic enzymes. Activated macrophages with their liberated cytokines or growth factors induce proliferation of cells, involved in inflammation, tissue repair and angiogenesis, sothat play an active role in the initiation, maintenance and progression of endometriosis. Macrophages product then accumulate and activate more macrophages, thus a positive cascade and cells-cytokines network established that facilitates implantation and growth of ectopic endometrial cells.It was proved that IL- 1, IL-2, IL-6, IL-8 and TNFa are all increased in the PF of women with endometriosis, and these cytokines mainly produced by peritoneal macrophages. Among these factors, interleukin 1 is a pivotal macrophage-derived cytokine which plays a key role in primary immune responses. Levels of IL-1β are elevated in the PF of women with endometriosis and IL-1β has been shown to upregulate cytokines and growth factors such as intergrin, MMP3, MMP4, IL-8, TNF and VEGF, which may contribute to vascularisation, adhesion, invasive and establishment of ectopic endometriotic lesions.IL-8 is a potent angiogenic, proinflammatory, growth-promoting cytokine. It stimulates the growth of ectopic, eutopic endometrial cells and DNA synthesis, and play a major role in ectopic endometrial cell implant. Until now, few data showed in the correlation between the IL-1β , IL-8 in PF of women with endometriosis. The expression of CD68( a specific antibody of the activated macrophage) and IL-1β, IL-8 in ectopic and eutopic endometrium of women with emdometriosis and their correlation remain unreported.Objectives (1 ) To detect the distribution and expression of macrophages inendometrium and to determine the correlation between the tissue accumulation of macrophages and the staging of endometriosis; (2) To investigate the correlation between the macrophages and it's products of IL-1β ,IL-8 and to clarify the changes of expression and function of macrophages in the lesions of endometriosisMaterials and MethodsMaterials In a series of 40 women with endometriosis undergoing operation, biopsies samples were collected from ovarian endometriosis cystoma and corresponding eutopic endometrium. As a control group, eutopic endometrium from 20 women operated on other gynecologic diseases such as myomas were also evaluated.Methods The immunohistochemical techniques with the antibody for the CD68, IL-1β and IL-8 were performed on paraffin wax sections of endometrial tissue and eutopic endometrium from patients with and without endometriosis . Immunostaining outcome was semi-quantified by the HSCORE. Routine HE staining was accomplished in all samples.Results(1) The infiltration of macrophages as shown by CD68-positive brown spots expressed in eutopic, ectopic endometrium. The number of CD68 positive cells are larger in the eutopic endometrium in women with endometriosis than in those without endometriosis(P<0.05). The ectopic endometrium are infiltrated more macrophages than eutopic endometrium in each group of the endometriosis women (p<0.01). Women with severe endometriosis harbored more macrophages than women with minor endometriosis or control group (P<0.01)(2) IL-1β positive stain in all endometrial endothelial cells and stromal cells. The expression of IL-1β were stronger in the ectopic endometrium than eutopic endometrim in endometriosis women (p<0.001). The expression of IL- 1β were stronger in eutopic endometrim in endometriosis women than in endometrium of women without endometriosis (p<0. 01)(3) IL-8 positive staining expressed in endometrial endothelial cell and stroma. In ectopic endometrium, IL-8 HSCORE values were significantly higher than those in normal eutopic endometrium (P<0.01) . There was no significantdifference in the IL-8 expression between the eutopic endometrium of women with and without endometriosis (P>0.05) .(4) There was a significant correlation between macrophages infiltration and immunoreaction of IL-1β or IL-8 in women with endometriosis( P<0.05). There was no correlation between them in control women (P=0.607) .( 5) There was a significant correlation between IL-1 β and IL-8 in women with endometriosis.( P<0. 01).There was no correlation between them in control women(P=0.552)Conclusions(1) Ectopic and the corresponding eutopic endometrium of women with endometriosis harbor more macrophages than the endometrium of women without endometriosis. The severity of endometriosis is associated with abundant recruitment and infiltration of macrophages, indicating that the activated macrophages in eutopic and ectopic endometrium of women with endometriosis contribute to the establishment, maintenance and advancement of this disease.(2) Endometriotic tissue had significantly higher immunostaining of macrophage-derived cytokines such as IL-1β, IL-8 than endometrium from both patients with and without endometriosis. Suggesting IL-1β and IL-8 may participate in an integrated inflammatory cascade that facilitates implantation and growth of ectopic endometrial cells in endometriosis women.(3) The intensity of immunostaining of IL-1β , IL-8 , and the numbers of macrophages infiltrated in endometriotic tissue were positively correlated, suggesting endometrial macrophages are associated with endometriosis and may play a central role in its etiology by releasing IL-1β, IL-8.