Bull seminal plasma stimulates in vitro production of TGF-beta, IL-6 and IL-8 from bovine endometrial epithelial cells, depending on dose and bull fertility

Seminal plasma (SP) regulates immune responses in the female reproductive tract through specific cytokines. It is not known whether SP from high fertility bulls (H) differs from SP from low fertility bulls (L). In this study, the cytokine response of bovine endometrial epithelial cells (bEEC) in culture was investigated after challenge with SP from two bulls of below average (L) or three bulls of above average fertility (H). The bEECs were challenged with 1% or 4% SP from L- or H-fertility bulls (L1, L4, H1, H4, respectively) or 1%, or 4% PBS as control (C1, C4) for 72 h. The culture media were analysed for concentrations (pg/million cells) of transforming growth factor beta (TGF-beta 1, TGF-beta 2 and TGF-beta 3) by Luminex, and Interleukin 6 and 8 (IL-6, IL-8) by ELISA. Challenge significantly affected production of TGF-beta 1, TGF-beta 2 and IL-8 compared to controls and was affected by bull fertility (p < 0.0001), SP concentration (p < 0.0001) and their interaction (p < 0.0001). A higher production of TGF beta 1, TGF-beta 2 and IL-8 (p < 0.0001), and also IL-6 (p < 0.01), resulted from challenge with high doses of SP, being higher for L than H (p < 0.05). For TGF-beta 3, fertility of bull (p < 0.05). For TGF-B3, fertility of bull (p < 0.05) and the interaction between fertility and concentration of SP were significant (p < 0.01). In conclusion, 4% SP from L bulls stimulated more TGF-beta 1, TGF-beta 2, TGF-beta 3, IL-6 and IL-8 production than SP from H bulls, indicating that stimulation of the endometrium is relevant for fertility. Seminal plasma from high fertility bulls seems to affect cytokine production in utero positively in inseminated cows.Funding Agencies|FORMASSwedish Research Council Formas [221-2011-512, 221-2010-1241]; Mahasarakham University; Veterinary Faculty at the Swedish University of Agricultural Sciences (SLU); Linkoping University via the Research Council in Southeast Sweden (FORSS) [378091/3129712013-2016]; Swedish Research Council VR, StockholmSwedish Research Council [521-2011-6353]