Expression of Toll-Like Receptors in the Mouse Testis Derived From In Vitro Embryo Culture and Embryo Transfer

Evidence suggests that Toll-like receptors (TLRs) may play developmental rather than immune roles in the mouse testis. Although all TLR proteins are present in the mouse testis, there are no studies that investigate the transcriptional expression of all TLR genes in physiological conditions. It also remains unexplored whether expression levels of TLR transcripts in mouse testis are influenced by in vitro embryo culture and embryo transfer. Therefore, the first objective of the present study was to examine transcriptional expression of all TLRs in mouse testis in physiological conditions. The second objective was to investigate whether transcriptional expressions of TLRs alter in testes of mice derived from transfer of blastocyst cultured under the atmospheric oxygen conditions, compared to those obtained from naturally ovulated females. Testis tissues of eight-week-old Agouti mice (C57BL/6 x BALB/c) were used in the current study. The study included one Control group (CG) and one Experimental group (EG). Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to assess the expressions of TLR genes. Data indicated that all TLR transcripts were present in the testis of CG and EG mice. Nonetheless, none of the TLR transcripts showed differential expressions between groups. TLR expression in the mouse testis appears to remain unaffected by in vitro embryo culture and embryo transfer. Expression of all TLRs in mouse testis under both physiological and detrimental conditions suggests that TLRs may have physiological roles in the process of spermatogenesis. Further studies are warranted to investigate the connection between TLRs and developmental processes of spermatogenesis.