Characterisation of antigen-presenting cells in the murine female reproductive tract and its draining lymph nodes

Despite the global burden of sexually transmitted diseases, the immunology of the female reproductive tract is poorly understood. An understanding of how the distribution of antigen presenting cells in the tissue and cross talk between cell types both at the site of antigen uptake and in the draining lymph nodes will be important for the design of new tools to manipulate local immune responses. The murine estrous cycle is characterised by large changes in the architecture of the vaginal and cervical epithelia in response to hormonal changes. Here, I show that the distribution of APCs in the epithelia of the vagina and cervix is not uniform. Neutrophils infiltrate the tissue in large numbers during the progesterone high stages of the murine estrous cycle, but this does not affect DC localisation. The iliac lymph nodes that drain the reproductive tract are structurally similar to other mucosal lymph nodes, but DCs are reduced in frequency compared to LNs draining other sites. RALDH expression, a marker for retinoic acid metabolism was also reduced in iliac compared to other peripheral lymph nodes. The murine lower female reproductive tract and its draining lymph nodes are, therefore, distinct from other mucosal tissues and lymph nodes and warrant further investigation.