Meeting Abstract
19.6 Tuesday, Jan. 4 Exploring the effects of pregnancy on Th1/Th2 immune tradeoffs in the African buffalo O’NEAL, D.M.*; JOLLES, A.E.; EZENWA, V.O.; University of Georgia; Oregon State University; University of Georgia dmoneal@uga.edu
Reproduction is costly and requires significant maternal investment. This investment increases as pregnancy progresses and maternal resources are allocated to fetal development and away from self-maintenance. This redirection of resources, potentially away from immune maintenance as well as other metabolic functions, can lead to suppression of the maternal immune response. Additionally, immune function can be suppressed to protect the fetal allograft from rejection by the maternal immune system. Suppression, however, may not be holistic. Th1 and Th2 immune responses are known to cross-regulate one another and cytokines produced by Th1 cells can suppress Th2 immune function and vice versa. This differential suppression could be extended through pregnancy. We looked for evidence of cross-regulation between Th1 and Th2 immune responses in wild caught African buffalo (Syncerus caffer) and investigated how reproduction may modify pre-existing tradeoffs in immune allocation. Female buffalo were captured across several reproductive stages and were assessed for adaptive immune function as indicated by Th1 (IFN-γ, IL-1β, TNF-α) and Th2 (IL-4, IL-10) cytokine levels. We predicted enhanced down-regulation of cytokine regulators associated with cell-mediated immunity and systemic inflammatory responses in pregnant compared to non-pregnant females and at more advanced stages of pregnancy. The results of this study will provide key insights into the nature of immune tradeoffs taking place during reproduction and provide information regarding the types of pathogens that pose the greatest threat to pregnant females. Moreover, these results may reveal key mechanisms by which within-host physiological processes scale up to influence patterns of disease across life-history stages in natural populations.
