Immunological Paradigms and the Pathogenesis of Ovine Chlamydial Abortion
Article first published online: 16 AUG 2010
© 2010 John Wiley & Sons A/S
American Journal of Reproductive Immunology
Special Issue: Special Issue on Domestic Animal Models of Reproductive Immunology
Volume 64, Issue 4, pages 287–294, October 2010
How to Cite
Entrican, G., Wattegedera, S., Wheelhouse, N., Allan, A. and Rocchi, M. (2010), Immunological Paradigms and the Pathogenesis of Ovine Chlamydial Abortion. American Journal of Reproductive Immunology, 64: 287–294. doi: 10.1111/j.1600-0897.2010.00907.x
- Issue published online: 2 SEP 2010
- Article first published online: 16 AUG 2010
- Submitted March 23, 2010; accepted June 30, 2010.
Citation Entrican G, Wattegedera S, Wheelhouse N, Allan A, Rocchi M. Immunological paradigms and the pathogenesis of ovine chlamydial abortion. Am J Reprod Immunol 2010
Successful mammalian pregnancy involves complex immunological interactions between the mother and foetus that are not yet fully understood. A number of immunological paradigms have been established to explain the failure of the maternal immune system to reject the semi-allogeneic foetus, mainly based on studies in mice and humans. However, as placental structure, gestation periods and number of concepti per pregnancy can vary greatly between mammals, it is not always clear how applicable these immunological paradigms are to reproduction in other species. Here, we discuss the predictions of three important immunological paradigms in relation to the pathogenesis of ovine enzootic abortion (OEA), a common cause of infectious abortion in sheep and other ruminants. OEA is caused by the intracellular Gram-negative bacterium Chlamydophila abortus that exhibits a tropism for placental trophoblast. The paradigms of particular relevance to the pathogenesis of OEA are as follows: (i) intracellular bacterial infections are controlled by TH1-type CD4+ve T cells; (ii) indoleamine 2,3-dioxygenase is expressed in the placenta to prevent immunological rejection of the semi-allogeneic foetus; and (iii) pregnancy is a maternal TH2-type phenomenon. We discuss the relevance and validity of these paradigms for chlamydial abortion and reproductive immunology in sheep.