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RESEARCH ARTICLE

The postpartum endometrial inflammatory response: a normal physiological event with potential implications for bovine fertility

Aspinas Chapwanya A E , Kieran G. Meade B F , Cathriona Foley A B , Fernando Narciandi A , Alexander C. O. Evans C , Michael L. Doherty D , John J. Callanan D and Cliona O’Farrelly A
+ Author Affiliations
- Author Affiliations

A Comparative Immunology Group, School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland.

B Animal & Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Co. Meath, Ireland.

C UCD School of Agriculture and Food Science, Belfield, Dublin 4, Ireland.

D UCD School of Veterinary Medicine, Belfield, Dublin 4, Ireland.

E Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, 0014, South Africa.

F Corresponding author. Email: kieran.meade@teagasc.ie

Reproduction, Fertility and Development 24(8) 1028-1039 https://doi.org/10.1071/RD11153
Submitted: 8 June 2011  Accepted: 16 February 2012   Published: 30 March 2012

Abstract

After calving, the bovine endometrium undergoes marked morphological and functional changes that are necessary for subsequent re-breeding. Regulation and integration of these key events are largely uncharacterised. Here, endometrial swabs and biopsies were taken at 15, 30 and 60 days postpartum (DPP) from 13 healthy primiparous cows, 10 of which subsequently conceived, with a view to characterising innate and inflammatory gene expression profiles. Endometrial biopsies exhibited severe inflammation (>75 leukocytes per high-power field) at 15 DPP, which had begun to resolve by 30 DPP and had completely resolved by 60 DPP. The severe inflammation at 15 DPP coincided with uterine infection in all cows and a significant increase (P < 0.05) in the expression of all of 16 genes investigated, including CD45, IL8, IL6, IL1, TNF, TAP, SAA3 and HP at 15 DPP, relative to 60 DPP. All of these parameters had begun to return to normal physiological levels at 30 DPP. Systemically, serum protein concentrations of IL-8 were elevated at 15 DPP compared with 60 DPP (78 pg mL–1 vs 48 pg mL–1; P = 0.02). These results indicate that endometrial inflammation, leukocyte infiltration and increased expression of pro-inflammatory, antimicrobial and acute-phase protein genes are expected features of the postpartum period, critical to bacterial clearance and uterine involution.

Additional keywords: endometrium, inflammation, innate immunity, involution.


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