RESUMO
Soluble isoforms of the non-classical Human Leukocyte Antigen (HLA)-G as well as Transforming Growth Factor (TGF)-ß is expressed in seminal plasma possibly influencing the pregnancy potential. We wanted to examine the association of seminal plasma sHLA-G, TGF-ß1, TGF-ß2 and TGFß3 with pregnancy success in a cohort of 127 couples and 4 single women attending fertility treatment with the use of assisted reproduction technologies (ART). Soluble HLA-G, TGF-ß1, TGF-ß2 and TGF-ß3 in seminal plasma did not fluctuate significantly over time. We did not find any impact of seminal plasma sHLA-G, TGF-ß1, TGF-ß2 and TGF-ß3 on time-to-pregnancy measured as number of treatment cycles. There was a significant association between concentrations of seminal plasma sHLA-G and HLA-G variations in the 3'untranslated region (3'UTR) of the HLA-G gene, supporting and extending previous findings. Furthermore, by comparing seminal plasma concentrations of sHLA-G, TGF-ß1, TGF-ß2 and TGF-ß3 in male subjects with reduced semen quality, male subjects with normal semen quality, and sperm donors, we found that TGF-ß2 was significantly lower, and TGF-ß3 was significantly higher, in seminal plasma from sperm donors. These findings suggest that TGF-ß isoforms may influence semen quality and fertility.