@article{miles_beetham_segerson_2002, title={Suppressor cell activity of ovine caruncular and intercaruncular tissues during the placentation period}, volume={58}, ISSN={["0093-691X"]}, DOI={10.1016/S0093-691X(01)00681-1}, abstractNote={We assessed the suppression of lymphocyte proliferation ovine endometrial cells recovered during each trimester (Days 45, 90, and 135) of pregnancy. We evaluated fractionated and unfractionated caruncular (C) and intercaruncular (IC) cells for suppression of cocultured peripheral blood lymphocytes (PBL) in phytohemagglutinin (PHA)-treated cultures. We also evaluated cells for the release of the suppressor factor into the culture medium and tested the factor for transforming growth factor-beta (TGF-beta) activity. Suppression of PHA-induced proliferation of PBL was evident for C and IC cells recovered from each day of pregnancy, and the activity was predominantly attributed to the population(s) of low-density (1.006-1.054 g/ml) cells. The activity was greater for unfractionated C than for IC cells on Day 45, whereas the pattern was reversed by Day 135 of pregnancy. For the C cells, the activity was greatest on Day 45 and least by Day 135. Although suppressor factor was released into the medium from cultured C and IC cells, its activity was not apparently mediated by TGF-beta. In conclusion, we observed a temporal pattern in suppressor activity for unfractionated endometrial cells during pregnancy. Suppression was predominately mediated by a population(s) of low-density cells. In addition, the cells released a soluble suppressor factor that seems to be unrelated to TGF-beta. The suppressor cells may provide immunological protection to the fetoplacental unit by suppressing specific lymphocyte responses directed toward conceptus tissues.}, number={6}, journal={THERIOGENOLOGY}, author={Miles, JR and Beetham, PK and Segerson, EC}, year={2002}, month={Oct}, pages={1097–1109} }
 @article{ireland_segerson_1999, title={Ovine endometrial cells fail to lyse K-562 target cells: a preliminary investigation}, volume={51}, DOI={10.1016/S0093-691X(99)00087-4}, abstractNote={The ability of unfractionated and fractionated endometrial cells to lyse K-562 target cells was investigated within ewes during the late luteal phase of the estrous cycle (Days 12 to 14) and pregnancy (Days 16 and 19). In separate experiments, lymphokine activated killer (LAK) cells and endometrial cells, both designated as effector cells, were co-cultured with chromium-51 (51Cr)-labeled K-562 target cells in varying effector: target cell ratios. At 22 h, lytic activity was assessed by the release of 51Cr into the culture medium. The LAK cells exhibited lytic activity in a ratio-dependent manner, whereas the unfractionated and fractionated endometrial cells failed to lyse the target cells. For ratios combined, the rate of cytotoxicity for unfractionated endometrial cells recovered from ewes in the cyclic and pregnant (Days 16 and 19 combined) groups was 13.9 and 5.4%, respectively. Although the findings are preliminary, they indicate that ovine endometrial cells recovered during the late luteal phase and early pregnancy failed to exhibit natural killer activity upon K-562 target cells.}, number={8}, journal={Theriogenology}, author={Ireland, A. C. and Segerson, E. C.}, year={1999}, pages={1431–1440} }
 @article{shipp_segerson_1998, title={Endometrial suppressor cells in beef cattle}, volume={50}, ISSN={["0093-691X"]}, DOI={10.1016/S0093-691X(98)00183-6}, abstractNote={Endometrial cells were recovered post mortem from cyclic and pregnant crossbred beef cattle (n = 5 each) on Days 16 to 18 after estrus, and were evaluated for their ability to suppress lymphocyte responses and release suppressor factor into the culture medium. The suppressor factor was assessed for transforming growth factor-beta (TGF-beta) activity. In addition, Percoll was used to fractionate endometrial cells from Angus cows (n = 4) on Days 16 to 18 of pregnancy to determine the density of the suppressor cells. Endometrial cells from cyclic and pregnant cows suppressed lymphocyte proliferative responses and released suppressor factor into the culture medium. The suppressor factor exhibited TGF-beta activity. Suppressor activities tended to be greatest for fractionated cells with densities of 1.01 and 1.095 g/mL. In conclusion, the bovine endometrium contains low- and high-density suppressor cells capable of releasing suppressor factor. The factor seems to be associated with TGF-beta.}, number={5}, journal={THERIOGENOLOGY}, author={Shipp, SA and Segerson, EC}, year={1998}, month={Oct}, pages={779–791} }
 @article{segerson_li_talbott_allen_gunsett_1998, title={Partial characterization of ovine intrauterine suppressor cells}, volume={58}, ISSN={["1529-7268"]}, DOI={10.1095/biolreprod58.2.397}, abstractNote={Ovine uterine cells that represented Day 14 cyclic and pregnant endometrium were fractionated with Percoll and evaluated for suppression of cocultured phytohemagglutinin (PHA)-induced peripheral blood lymphocyte (PBL) proliferation and for the presence of T-lymphocyte markers. Uterine cells were then evaluated for suppressor activity following the depletion of conventional lymphocyte classes (i.e., T-, B-, and NK-like) with complement + antibody treatment. In addition, supernatant (derived from cultured uterine cells) was tested for transforming growth factor beta (TGFbeta) activity using neutralization antibodies to TGFbeta. Fractionated uterine cells (density range of 1.002-1.056 g/ml) from cyclic and pregnant ewes suppressed PHA-induced proliferation of PBL, and the majority (69.5%) of these cells were < or = 5.2 microm in diameter. Percentages of CD5+, CD4+, and CD8+ lymphocytes recovered from endometrial curettage were less for cells in this density range than for cells with greater densities. Uterine cells released suppressor factor(s) into the culture medium (supernatant); however, suppressor activity was unaffected by either anti-TGFbeta or complement + antibody treatment. In conclusion, low-density uterine cells from Day 14 cyclic and pregnant ewes suppressed the proliferation of cocultured PBL and released a suppressor factor(s) into the medium that did not exhibit TGFbeta activity. It is unlikely that the suppressor cells comprise conventional T-, B-, or NK-like lymphocyte lineages.}, number={2}, journal={BIOLOGY OF REPRODUCTION}, author={Segerson, EC and Li, H and Talbott, CW and Allen, JW and Gunsett, FC}, year={1998}, month={Feb}, pages={397–406} }
 @article{segerson_li_talbott_1997, title={Estradiol-17 beta and progesterone increase ovine uterine suppressor cell activity}, volume={75}, DOI={10.2527/1997.75102778x}, abstractNote={We evaluated the regulation of ovine uterine (UT) suppressor cell activity by progesterone (P4), estradiol-17 beta (E2), and P4 + E2 in ovariectomized (OVX) ewes. Following 14 d of steroid injections, endometrial cells (designated as UT cells) were recovered postmortem, and unfractionated and fractionated cells were assessed for suppression of autologous phytohemagglutinin (PHA)-treated peripheral blood lymphocytes (PBL). Supernatants from cultured UT cells were also assessed for suppressor activity. In other experiments, UT cells recovered from nontreated OVX ewes were cocultured with PHA-treated PBL and varying concentrations (1 x 10(-11) to 1 x 10(-5) M) of each steroid preparation. Supernatants from separate cultures that contained UT cells and steroids were evaluated for suppressor activity. Uterine cells from control and steroid-treated ewes suppressed proliferative responses of PHA-treated PBL; however, suppressor activity of UT cells was greater (P < .05) for E2-treated than for control and P4-treated ewes. Uterine suppressor cells from steroid-treated ewes sedimented in Percoll within a density range of 1.002 to 1.056 g/mL. Uterine cells from all ewes released suppressor factor(s) into the culture medium; however, the activity of the supernatant from the cultured cells was not increased for the steroid-treated ewes. For cocultures that contained steroids and cultures that contained supernatant, suppressor activity of the UT cells was increased by specific concentrations of each steroid preparation. These findings demonstrate that reproductive steroids augment ovine UT suppressor cell activity.}, number={10}, journal={Journal of Animal Science}, author={Segerson, E. C. and Li, H. and Talbott, C. W.}, year={1997}, pages={2778–2787} }
 @article{segerson_talbott_1997, title={Transforming growth factor-beta 2 activity is temporally associated with a porcine high-molecular-weight uterine component recovered during early pregnancy}, volume={75}, DOI={10.2527/1997.752462x}, abstractNote={A high-molecular-weight component (> or = 4 MDa, eluted at void volume of a Sepharose CL-6B column) was recovered postmortem from uterine luminal secretions from crossbred gilts (4/d) on d 9, 12, 15, and 18 of pregnancy and d 15 of the cycle. It was tested for suppression of peripheral blood lymphocyte (PBL) proliferation and for transforming growth factor-beta (TGF-beta) activity. In Exp. 1, the > or = 4 MDa component was cultured with phytohemagglutinin (PHA)-treated PBL. Parallel cultures received a pan-specific neutralization antibody to TGF-beta. In Exp. 2, cultures contained PHA-treated PBL, the > or = 4 MDa component and neutralization antibodies to either TGF-beta 1 or -beta 2. In Exp. 1, the > or = 4 MDa component recovered from uterine secretions for d-12 to d-18 pregnant gilts and d-15 cyclic gilts suppressed (P < .001) the proliferation of PHA-treated PBL; however, suppressor responses were reversed (P < .001) by anti-TGF-beta only for the > or = 4 MDa component recovered from gilts on d 15 and 18 of pregnancy. In Exp. 2, anti-TGF-beta 2 reversed (P < .05) the suppressor activity of the > or = 4 MDa component recovered from gilts on d 15 of pregnancy. In conclusion, a temporal pattern of TGF-beta activity was associated with a > or = 4 MDa carrier recovered from porcine uterine luminal secretions during early pregnancy. For uterine secretions recovered on d 15, suppressor activity was at least partly attributed to TGF-beta 2.}, number={2}, journal={Journal of Animal Science}, author={Segerson, E. C. and Talbott, C. W.}, year={1997}, pages={462–468} }