Immunomodulation with pentoxifylline abrogates macrophage-mediated infertility in an in vivo model: a paradigm for a novel approach to the treatment of endometriosis-associated subfertility.

Although present consensus holds that endometriosis-associated subfertility is the result of an adverse effect of hyperactivated macrophages on early reproductive events, most treatments for endometriosis are directed at the suppression of endometriotic implants. We hypothesized that periovulatory immunomodulation of macrophage activation and inflammatory mediator production might be a more effective approach to this problem. In this experiment, heterologous transfer of activated peritoneal inflammatory cells within a syngeneic strain of mice was used as an in vivo model for the peritoneal inflammatory environment of the endometriosis patient. Intraperitoneal transfer of hyperactivated macrophages, but not basal state macrophages, significantly inhibited fertilization. This activity was reversed by periovulatory pentoxifylline treatment. Immunomodulation of peritoneal inflammatory cell hyperactivation with pentoxifylline may represent a new modality for the treatment of endometriosis-associated subfertility.