QUANTIFICATION OF SPERMATOGENESIS BY DUAL-PARAMETER FLOW-CYTOMETRY

Objective: To investigate the usefulness of dual-parameter flow cytome try of testicular fine-needle aspirates for the quantification of sper matogenesis. Immunofluorescence staining for vimentin was introduced t o discriminate vimentin-negative germ cells from vimentin-positive str omal cells. The results of flow cytometry were compared with testicula r morphology and immunohistochemistry in cases of regular and disturbe d germ cell maturation. Design: Testicular fine-needle aspiration and surgical biopsy were performed in 50 autopsy cases. The fine-needle as pirates were double stained for the intermediate filament vimentin by indirect immunofluorescence and DNA propidium iodide and analyzed by f low cytometry. Surgical biopsies were examined by light microscopy. Th e distribution of vimentin-positive cells was evaluated by immunohisto chemistry. Results: A comparison of morphology and flow cytometric ana lysis yielded characteristic quantitative distribution patterns of the different germ cell and somatic cell populations in regular and distu rbed spermatogenesis. All three ploidy compartments of the germ epithe lium correlated with high statistical significance with the respective histologic diagnoses. Moreover, a marked quantitative increase of str omal cells could be demonstrated in spermatogenetic disorders. Conclus ions: The simultaneous analysis of the cellular DNA content and the in termediate filament vimentin by flow cytometry enables a detailed inve stigation of spermatogenetic disorders. Quantitative changes of the re lationships between germ cells and somatic cells can be selectively in vestigated.