Distribution of leukocytes in the epithelium and interstitium of four regions of the Lewis rat epididymis

✍ Scribed by Flickinger, Charles J. ;Bush, Leigh A. ;Howards, Stuart S. ;Herr, John C.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 641 KB
• Volume: 248
• Category: Article
• ISSN: 0003-276X
• DOI: 10.1002/(sici)1097-0185(199707)248:3<380::aid-ar11>3.0.co;2-l

✦ Synopsis

Background: Leukocytes expressing different surface markers were studied in four regions of the epididymis of Lewis rats. Cells resembling lymphocytes or monocytes had been described in the epididymis, but previous studies differed as to their nature and immunologic significance.

Methods: Frozen sections were immunocytochemically stained with monoclonal antibodies W3/25, OX-8, OX-42, and RLN-9D3, which are directed toward markers on CD41 cells, CD81 cells, macrophages, and B lymphocytes, respectively. The concentration of stained cells in the epithelium and interstitial tissue of the initial segment, caput, proximal cauda, and distal cauda regions was determined by a procedure based on the optical disector method.

Results: CD41 leukocytes were present in greater concentration than CD81 cells or macrophages in both the epithelium and interstitial tissue of all four regions. In the epithelium, the concentration of CD81 leukocytes was greater than that of macrophages in the initial segment, caput, and distal cauda. In the interstitium, however, the concentration of macrophages exceeded that of CD81 cells in both parts of the cauda. Macrophages and T lymphocytes were generally present in greater concentrations in the interstitium than in the epithelium, especially in the more proximal parts of the epididymis. In contrast to T cells, B lymphocytes were not detected in the interstitium or epithelium of any of part of the epididymis, despite prominent staining of B cells in other locations.

Conclusions: The epididymal epithelium of the Lewis rat contains many T lymphocytes, which may correspond to 'halo' cells. CD41 leukocytes predominate in all regions of the epididymis. The interstitium may function as a reservoir of leukocytes for the epithelial compartment. The epididymis is not normally a site for local immunoglobulin synthesis.