The effect of treatment with immune modulators on endometrial cytokine expression in mares susceptible to persistent breeding-induced endometritis.

This study investigates the impact of immune modulators on the gene expression of inflammatory markers in mares susceptible to persistent endometritis following breeding. The results revealed that the use of specific immune modulators could adjust the expression of certain inflammatory genes in the horse’s uterus, offering new insights for potential treatments.

Research Objectives and Hypothesis

The purpose of the study was to assess the effect of immune modulation on the gene expression of inflammatory markers in mares susceptible to persistent breeding-induced endometritis. Specifically, the researchers wanted to analyze the changes 6 hours post-breeding, considered a significant point in the uterine innate immune response. They hypothesized that immune modulation could alter endometrial cytokine expression within this time frame.

Methodology

• The researchers designed and executed a randomised controlled study. They specifically looked at the effects of a mycobacterial cell wall extract and dexamethasone on endometrial gene expression post-insemination.
• Six mares, known to be susceptible to persistent breeding-induced endometritis, were chosen for the study. They were inseminated during three oestrus cycles with nonviable sperm. Alongside this, they were either not treated, treated with dexamethasone at insemination time, or given the mycobacterial cell wall extract 24 hours before insemination. The treatments were randomly ordered and each mare served as her own control.
• Through endometrial biopsies taken 6 hours after breeding, the researchers could analyze the expression of various genes related to inflammation (interleukin [IL]1β, IL6, interferon γ, IL10 and IL1RA) using quantitative polymerase chain reaction analysis.
• The results were processed through an ANOVA and were considered significant if P<0.05.

Results

• The data analysis revealed that the expression of IL1β mRNA decreased post-treatment with dexamethasone or the mycobacterial cell wall extract when compared to the control group. However, there were no detectable changes in the mRNA expression of the other cytokines post any of the treatments.

Conclusions

• The findings of this research suggest that treatment with immune modulators can alter the gene expression of IL1β post insemination. This provides an avenue for further exploration; a more detailed understanding of immune modulation mechanisms within the equine uterus could improve the treatment practices for persistent breeding-induced endometritis.