Inflammatory Infiltrate in Prostatic Hyperplasia—Evidence of a Host Response to Intraprostatic Spermatozoa?

The inflammatory infiltrate was characterised in 20 samples of prostatic hyperplasia using cell surface specific monoclonal antibodies. The infiltrate was composed predominantly of CD-3+ T-lymphocytes. The distribution of the T-lymphocyte subsets (CD-4 and CD-8) between the epithelial and stromal components of the gland was significantly different, with most of the intra-epithelial infiltrate being CD8+, T cytotoxic/suppressor cells. This may be a necessary immunological barrier, as in the epididymis, to prevent the development of autoimmunisation to sperm antigens. Large numbers of CD4+ T helper/inducer cells and significant numbers of CD-11c+ macrophages were demonstrated in the extra-glandular stromal tissues, suggesting a delayed type hypersensitivity reaction. Intraprostatic spermatozoa have been demonstrated recently and we have confirmed this finding on post mortem specimens. It is postulated that the presence of an intra-epithelial cytotoxic barrier and the marked stromal infiltrate may be due, in part, to the intermittent presence of spermatozoa within the prostate.