A novel endometriosis inducing factor in women with endometriosis

To confirm the hypothesis of the presence of a possible endometriosis inducing factor(s) (EIF) in the blood of women with endometriosis.

Forty infertile women were studied. The study group compromised of fifteen women of each three different degrees of endometriosis and fifteen women without endometriosis as a control group. Stem cells are characterized by being spindle shaped and proliferate in appropriate culture indefinitely. The women sera were co-cultured with mesenchymal stem cells (MSCs) which were followed up weekly to look for morphological changes and to detect Annexin 1 marker and ß-actin gene by reverse transcriptase polymerase chain reaction.

MSCs cultured with sera of cases with, mild, moderate and severe endometriosis, showed morphological changes to be columnar and cuboidal shaped cells -resembling endometrial cells and glands- by the 4th week in 60%, 60% & 100% respectively. These cells were detected from as early as the first week in women with moderate and severe types (20% for each group). The percentage of the change into endometrial like cells increased among the three groups where it was 30±25.8%, 45±29.9% and 75±37.9% respectively. Moreover, increasing number of endometrial like cells are detected weekly, the more severe the disease is. None of the cultures of serum of the control group had made such changes all over the study. Furthermore, with more differentiation there was a considerable decrease in number of stem cells. These differentiated cells expressed the Annexin-1 marker.

It was evident that serum of women with endometriosis posses a factor(s) that enables the MSCs to be transformed into endometrial like cells and glands in vitro. This finding supports a new theory for the etiology of endometriosis. This observation may have a tremendous effect on the therapeutic implications of this debilitating condition.