Monocyte chemotactic protein-1 (MCP-1), its receptor, and macrophages in the perifollicular stroma during the human ovulatory process

Objective To evaluate the expression and localization of the macrophage-specific chemokine monocyte chemotactic protein-1 (MCP-1), CC chemokine receptor 2 (CCR2), and macrophages (CD68) in the perifollicular stroma of different phases of the human ovulatory process and its relation to macrophage influx. Design Experimental study on patient-controlled material. Setting University hospital. Patient(s) Twenty-eight women planned to undergo laparoscopic sterilization. Intervention(s) Surgery was performed at either of four distinct ovulatory phases, and a biopsy sample was obtained from the perifollicular stroma of the ovulatory follicle. Main Outcome Measure(s) Real-time polymerase chain reaction, immunoblotting, and immunohistochemistry were used for measurements of MCP-1, CCR2, and macrophages. Result(s) The messenger RNA levels of MCP-1 in the perifollicular stroma increased from the preovulatory to the late ovulatory phase and declined during the postovulatory phase. A higher density of macrophages was found in the preovulatory and early ovulatory phases compared with late and postovulatory phases. Monocyte chemotactic protein-1 and CCR2 were present in the stroma. Protein expression of CD68 and CCR2 were identified in the four ovulatory phases. Conclusion(s) This study demonstrates an upregulation of MCP-1 in the stroma compartment around the human follicle during the ovulatory process, and a high density of macrophages was found at earlier phases. Thus, inflammation-like reactions are integral in the ovulatory process and may be targeted to stimulate or inhibit this process.