Baker J M, Bamford A I, Antczak D F
James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
J Immunol. 1999 Apr 15;162(8):4496-501.
Maternal immune recognition of the developing conceptus in equine pregnancy is characterized by the strongest and most consistent alloantibody response described in any species, a response directed almost exclusively against paternal MHC class I Ags. This work investigated the cellular immune response to paternal MHC Ags in pregnant and nonpregnant horses and donkeys, and in horses carrying interspecies hybrid mule conceptuses. We observed profound decreases in classical, MHC-restricted, CTL activity to allogeneic paternal cells in peripheral blood lymphocytes from both horse mares and donkey jennets carrying intraspecies pregnancies, compared with cells from nonpregnant controls. This is the first evidence in a randomly bred species for a generalized systemic shift of immune reactivity away from cellular and toward humoral immunity during pregnancy. Surprisingly, mares carrying interspecies hybrid mule conceptuses did not exhibit this transient, pregnancy-associated decrease in CTL activity. The failure of interspecies pregnancy to down-regulate cellular immune responses may be a heretofore-unrecognized, subtle barrier to reproductive success between species.
母马妊娠期间对发育中胎儿的免疫识别，其特征是在所有物种中表现出最强且最一致的同种抗体反应，这种反应几乎完全针对父本的MHC I类抗原。这项研究调查了怀孕和未怀孕的马、驴以及怀有异种杂交骡胎儿的马对父本MHC抗原的细胞免疫反应。我们观察到，与未怀孕的对照组相比，怀有同种胎儿的母马和母驴外周血淋巴细胞中，针对同种异体父本细胞的经典的、MHC限制的CTL活性显著降低。这是在随机交配物种中首次有证据表明，妊娠期间免疫反应会普遍从细胞免疫向体液免疫发生全身性转变。令人惊讶的是，怀有异种杂交骡胎儿的母马并未出现这种与妊娠相关的CTL活性短暂降低的情况。异种妊娠未能下调细胞免疫反应，这可能是迄今为止未被认识到的、物种间生殖成功的一个微妙障碍。
