Secretion of ovine lymphocyte suppressor factor from curetted uterine luminal cells

The secretion of ovine lymphocyte suppressor factor from jugular vein (JV), uterine vein (UV), and curetted hemopoietic uterine luminal (UL) mononuclear cells was evaluated on d 14 of the cycle, following ovariectomy (OVX) and after 14 d of progesterone injections (OVX + P4, 1 mg/kg BW). Mononuclear cells (predominantly lymphocytes) were harvested by Ficoll-Paque and placed into culture (2.5 x 10(6).mL-1.well-1 in RPMI-1640). Cellular supernatants were obtained at 72 h and volumes (5 to 50 microL) were tested for suppression of phytohemagglutinin (PHA [.08 microgram l)-treated peripheral blood lymphocytes (1.0 x 10(5)). In a concurrent experiment, PHA-treated JV, UV, and UL cells (1.0 x 10(5)) were cultured singly and JV cells (1.0 x 10(5)) were also cocultured with each of 1.0 x 10(5), 5.0 x 10(4), and 2.5 x 10(4) UV and UL cells. The incorporation of thymidine into DNA was quantified at 60 h. For the cellular supernatant experiment, thymidine incorporation was affected by reproductive phase (P less than .036), lymphocyte source (P less than .0001), and phase x source (P less than .004). For UL cells, the degree of suppressor activity follows: d 14 greater than OVX greater than OVX+P4 (P less than .05). The UL supernatant from OVX+P4-treated ewes and supernatants of JV and UV cells, irrespective of reproductive phase, lacked suppressor activity. Sephacryl S-200 chromatography revealed that UL supernatant from d-14 ewes contained a greater than or equal to 248,000 molecular weight suppressor macromolecule. For the cellular coculture experiment, thymidine incorporation was affected by reproductive phase (P less than .05) and lymphocyte source (P less than .0001).(ABSTRACT TRUNCATED AT 250 WORDS)