Immunohistochemistry for HSp17 in human testis, ejaculated spermatozoa, and paradigmatic human ciliated epithelial cells. (A) Histologic section of healthy testis. HSp17 was found in spermatocytes and abundantly in spermatids, while spermatogonia and Sertoli cells were found to be immunonegative. Hsp17 was strongly found throughout the principal piece of the flagellum in a large amount of fertile ejaculated spermatozoa (inset). (B) Histologic section of ductuli efferenti of the male germinal tract, (C) tubes of the female genital tract, (D) trachea, (E) larynx, and (F) lung. (B-F) HSp17 was expressed in the cytoplasm of lining ciliated epithelial cells and their cilia. Original magnification × 400 for panels A-C and F; × 1000 for panels D, E, and inset. Indirect immunoperoxidase staining was used.