Endometrial integrin expression in women with recurrent implantation failure after in vitro fertilization and its relationship to pregnancy outcome

Abstract

To determine expression of integrins α₁, α₄, and αVβ₃ in the glandular and luminal epithelium, stroma, and cells in the blood vessel walls of the endometrium from women with recurrent implantation failure (RIF) and to determine if they are of prognostic value in determining pregnancy outcome. Prospective nonrandomized study. Department of reproductive medicine. Forty-five women with RIF and six healthy fertile women were recruited. RIF was defined as the failure to conceive after the transfer of four good-quality embryos in three or more fresh or frozen cycles. Endometrial biopsy samples were obtained from women with RIF and control women on days LH+7-LH+9 of the cycle. Expression of integrins α₁, α₄, and αVβ₃ was determined by immunohistochemistry. A semiquantitative measurement of expression of each integrin protein in the luminal and glandular epithelium, stroma, and cells in the blood vessel walls was determined by H-score analysis. Expression of integrins α₁ and α₄ was greatest in the luminal and glandular epithelial cells and the cells in the blood vessel wall, and significantly higher expression of integrins α₁ and α₄ was seen in the glandular epithelium compared with the luminal epithelium (H-scores: α₁ 293 ± 15 and 180 ± 12, α₄ 287 ± 14 and 191 ± 11, respectively). Expression of αVβ₃ in the epithelium and blood vessels was also greater than in the stroma but there was no significant difference in expression of αVβ₃ in glandular and luminal epithelium. No significant difference in H-scores was seen for α₁, α₄, and αVβ3 expression in any of the endometrial compartments in tissue from women with RIF and control women. No significant difference in α₁, α₄, and αVβ₃ expression in any compartment was observed between those who achieved a clinical pregnancy after subsequent assisted conception treatment (n = 21) and those who were unsuccessful (n = 24). RIF, when defined as failure to achieve a clinical pregnancy after the transfer of at least four good-quality embryos in three transfer cycles, is not associated with abnormal endometrial integrin expression. In addition, the expression of integrins α₁, α₄, and αVβ₃ appears to have no prognostic value in subsequent IVF treatment.