Presence and distribution of leucocyte subsets in the murine epididymis after vasectomy

Summary Male mice were vasectomized by ‘open‐ended’ or ‘closed’ techniques. After 4 weeks the cell‐mediated immune reactions were compared with those of sham‐operated animals by immunohistochemical localization of leucocytes, using specific monoclonal antibodies. Macrophages and MHC class II antigen‐positive cells were the major cell types to appear in all regions of the epididymis after both types of operation. There was recruitment of T‐helper/inducer leucocytes but not of T‐suppressor‐cytotoxic cells. An increased presentation of macrophage‐migration inhibiting factor antigen appeared in interstitial and peritubular locations. After ‘closed’ and ‘open‐ended’ vasectomy granulomata developed in the epididymis. The sperm‐containing lumen of these granulomata was invaded by macrophages, MHC class II‐positive cells and T‐helper/inducer lymphocytes. This mouse model thus reveals a significant epididymal inflammatory response of the epididymis to vasectomy.