Endometriotic haptoglobin binds to peritoneal macrophages and alters their function in women with endometriosis

Proteolytic tailoring of the heat shock protein 70 and its implications in the pathogenesis of endometriosis

“…Additionally, higher expression of IL-6 was seen in ECE tissues, as also reported by others (31)(32)(33). IL-6 stimulates haptoglobin production (34,35), and increased haptoglobin levels have been held liable for the establishment and persistence of endometriosis (36). Interestingly, our previous study had also demonstrated increased haptoglobin expression in ECE (3).…”

Whole genome deoxyribonucleic acid microarray analysis of gene expression in ectopic versus eutopic endometrium

“…Both haptoglobin and CD163 antigen are involved in heme recycling (45); perhaps they are involved in the recycling of heme from retrogradely shed menstrual blood. Sharpe-Timms et al have also shown that endometriotic haptoglobin alters the function of peritoneal macrophages (6), which implicates haptoglobin in the altered immune responses that have been suggested to be involved in the establishment of endometriosis (2).…”

“…A variety of studies have examined gene expression in endometriosis one gene at a time; these studies have been well reviewed and summarized (4,5). Examples of genes that have been reported to exhibit differential expression in eutopic versus ectopic endometrium include intercellular adhesion molecule (ICAM-1) (4), integrins (4), tissue inhibitor of metalloproteinases (TIMP-2) (4, 5), haptoglobin (6,7), aromatase (4,8), and 17b-hydroxysteroid dehydrogenase (17b-HSD) (9). Moreover, growth factors and cytokines that regulate these proteins have been shown to be altered.…”

“Spot”-ting differences between the ectopic and eutopic endometrium of endometriosis patients

“…Our observation is in accordance with the results obtained by Piva et al (34), who established that endometriotic lesions synthesize and secrete into the peritoneal fluid a differentially sialyated and fucosylated form of haptoglobin. The altered form of haptoglobin has been found to bind to peritoneal macrophages, reduce their phagocytic capacity, and increase the production of cytokines (35).…”