ASSESSMENT OF GERM-CELL KINETICS IN THE TESTES OF PATIENTS WITH VARICOCELE USING IMAGE-ANALYSIS OF IMMUNOSTAINED PROLIFERATING CELL NUCLEARANTIGEN

Objectives To examine the germ-cell kinetics of varicocele testis usin g proliferating cell nuclear antigen (PCNA) immunostaining and image c ytometry to evaluate the staining intensity, and to compare the prolif erative index (PI) of varicocele and normal testes. Patients and metho ds Fifty-six testicular biopsy specimens were taken from 28 patients w ith varicocele during high ligation. The specimens were fixed and embe dded in paraffin, and sections immunostained using an anti-PCNA antibo dy. The PI was measured using an image analyser and expressed as the p ercentage of the total nuclear area stained positively with PCNA monoc lonal antibody, assessed from > 20 seminiferous tubules. Sections stai ned with haematoxylin and eosin were used to determine Johnsen's score using conventional microscopy. Normal control testicular biopsies wer e obtained from subjects undergoing vasectomy.Results In patients with varicocele, both testes had a significantly lower PI than normal test es; the mean (SD) PI of the right and left testes was 11.3% (4.1) and 11.3% (4.8), respectively, and the PI of normal testes was 21.7% (3.1) . There was no significant correlation between PI and sperm concentrat ion or Johnsen's score. Conclusion PI is useful for assessing germ-cel l kinetics; in patients with varicocele both testes showed a deteriora tion in DNA synthesis, suggesting that reduced DNA synthesis is one of the causes of spermatogenic dysfunction in the varicocele testes.