The influence of extracellular matrix proteins on T-cell proliferation and apoptosis in women with endometriosis or uterine leiomyoma.

PROBLEM

Interactions between the extracellular matrix (ECM) and peripheral blood T cells in women with endometriosis and leiomyoma are hardly unknown. We have investigated the influence of two major ECM components, collagen IV (C-IV) and fibronectin (Fn), on T-cell proliferation and apoptosis in women with endometriosis and uterine leiomyoma. beta1 integrin expression, responsible for interactions with ECM proteins, was also studied.

METHOD OF STUDY

Peripheral blood lymphocytes were obtained from 53 women (17 with uterine leiomyomas, 18 with endometriosis, and 18 from healthy donors). T cells were exposed to ECM proteins co-immobilized with monoclonal antibody anti-CD3 for 72 hr. Apoptosis and S phase of the cell cycle of the T cells were studied by DNA analysis using flow cytometry. The proliferation of T cells was evaluated by MTT assay. The percentage of CD3+ cells expressing CD29 (beta1 integrin chain) was evaluated by double-color flow cytometry. Results were analyzed statistically using the Mann-Whitney test.

RESULTS AND CONCLUSIONS

(1) A general increase in the percentage of T cells in S phase could be seen in women with endometriosis and uterine leiomyoma in all culture conditions what may suggest general activation of T cells. (2) A significant increase in the percentage of cells in S phase was shown only in the case of T cells exposed to anti-CD3 + C-IV in both women with uterine leiomyoma and endometriosis. (3) However, no apoptotic cells were observed. (4) T cells from patients with uterine leiomyoma exhibited significantly increased level of proliferation after culture with anti-CD3 + C-IV. (5) More T cells expressed beta1 integrin in women with endometriosis or uterine leiomyoma than in healthy donors. Our data may suggest that increased beta1 integrin expression may enhance T-cell-ECM interactions, which may be responsible for the increased proliferation of T cells but not for apoptosis. Therefore, it is possible that interactions of T cells with ECM proteins, especially with C-IV, may contribute to the pathogenesis of endometriosis and uterine leiomyoma.