Effect of culture conditions on the obtention of boar epididymal epithelial cell monolayers

Morphology of the epididymal duct of the domestic pig (Sus scrofa domesticus)

The study provides a general overview of the morphology of the epididymal duct in pigs. Four epididymides from two sexually mature boars were dissected into 32 segments and examined histologically. Duct lumen and wall thickness were measured and relative surface area of different components was assessed by Chalkley's random hit method. The epithelial lining was characterized at X1000. Lumen diameter and wall thickness of efferent ductules averaged 177 and 30 µm, respectively. Of the epididymal duct from caput to distal corpus the luminal diameter was 332 µm, with a narrower section in the proximal corpus. Wall thickness averaged 70 µm. In the cauda, luminal diameter and wall thickness increased to 717 and 751 µm, respectively. The epithelial lining of the efferent ductules consists of a single layer of columnar cells with average height 21 µm. The lining of the epididymal duct consists of ciliated, pseudo-stratified columnar epithelium composed of "basal cells" and "principal cells." Particularly tall principal cells (96 µm) were found in the proximal caput. Height decreased to 40 µm at the distal cauda. Microvilli from principal cells were 14-17 µm long in the distal caput but decreased to 5 µm in the distal cauda. The epithelial lining was folded in the proximal caput and more so in the distal cauda. Secretory granules (epididymosomes) were present in small amounts in efferent ductules and epididymal duct; the largest quantities occurred in the distal cauda. Leukocytes were present throughout the duct, albeit in insignificant numbers. Chalkley's random hit method showed rapid spermatozoan transport through efferent ductules and proximal caput in large amounts of fluid. Sperm concentration increased due to fluid resorption in the proximal caput, was highest from caput flexure to proximal cauda and decreased at the caudal flexure, indicating secretory activity.

Characterization of primary cultures of adult human epididymis epithelial cells

OBJECTIVE

To establish cultures of epithelial cells from all regions of the human epididymis to provide reagents for molecular approaches to functional studies of this epithelium.

DESIGN

Experimental laboratory study.

SETTING

University research institute.

PATIENT(S)

Epididymis from seven patients undergoing orchiectomy for suspected testicular cancer without epididymal involvement.

INTERVENTION(S)

Human epididymis epithelial cells harvested from adult epididymis tissue.

MAIN OUTCOME MEASURE(S)

Establishment of a robust culture protocol for adult human epididymal epithelial cells.

RESULT(S)

Cultures of caput, corpus, and cauda epithelial cells were established from epididymis tissue of seven donors. Cells were passaged up to eight times and maintained differentiation markers. They were also cryopreserved and recovered successfully. Androgen receptor, clusterin, and cysteine-rich secretory protein 1 were expressed in cultured cells, as shown by means of immunofluorescence, Western blot, and quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The distribution of other epididymis markers was also shown by means of qRT-PCR. Cultures developed transepithelial resistance (TER), which was androgen responsive in the caput but androgen insensitive in the corpus and cauda, where unstimulated TER values were much higher.

CONCLUSION(S)

The results demonstrate a robust in vitro culture system for differentiated epithelial cell types in the caput, corpus, and cauda of the human epididymis. These cells will be a valuable resource for molecular analysis of epididymis epithelial function, which has a pivotal role in male fertility.