In-depth quantitative proteome analysis of seminal plasma from men with oligoasthenozoospermia and normozoospermia.

Can seminal plasma markers for oligoasthenozoospermia be identified by comparison of the human seminal plasma proteome in men with oligoasthenozoospermia and normozoospermia? An in-depth quantitative proteome analysis was conducted using a high-throughput method named isobaric tag for relative and absolute quantification. A total of 734 seminal plasma proteins were quantified by mass spectrometry. Compared with the seminal plasma from men with normozoospermia, 22 upregulated proteins and 20 downregulated proteins were identified in the oligoasthenozoospermic seminal plasma. These differential seminal plasma proteins were involved in various physiological processes, including metabolism, transport, antioxidation and immune response. The confidence of some proteome data was further verified by western blot of (prostate-specific antigen [KLK3], lactotransferrin [LTF], alpha-1-antitrypsin [SERPINA1] and glyceraldehyde-3-phosphate dehydrogenase [GAPDH]). Additionally, 38% of the seminal plasma proteins identified in this study have not been reported in previously published studies on seminal plasma proteome, and 53% of our seminal plasma proteins were shared with published studies on human plasma proteome. Our seminal plasma proteome research provides new complementary high-confidence data, and also enhances understanding of the pathogenic mechanisms in oligoasthenozoospermia.