Whey-acidic protein four-disulfide core domain (WFDC) genes display putative roles in innate immunity and fertility. In mice, a locus on chromosome 2 contains 5 and 11 Wfdc genes in its centromeric and telomeric subloci, respectively. Although Wfdc genes are highly expressed in the epididymis, their contributions to epididymal function remain elusive. Here, we investigated whether Wfdc genes are regulated in response to lipopolysaccharide (LPS)-induced epididymitis, an inflammatory condition that impairs male fertility. We induced epididymitis in mice via (i) interstitial LPS injection into epididymal initial segment and (ii) intravasal LPS injection into the vas deferens towards cauda epididymis. Interstitial ... More
Whey-acidic protein four-disulfide core domain (WFDC) genes display putative roles in innate immunity and fertility. In mice, a locus on chromosome 2 contains 5 and 11 Wfdc genes in its centromeric and telomeric subloci, respectively. Although Wfdc genes are highly expressed in the epididymis, their contributions to epididymal function remain elusive. Here, we investigated whether Wfdc genes are regulated in response to lipopolysaccharide (LPS)-induced epididymitis, an inflammatory condition that impairs male fertility. We induced epididymitis in mice via (i) interstitial LPS injection into epididymal initial segment and (ii) intravasal LPS injection into the vas deferens towards cauda epididymis. Interstitial and intravasal LPS induced a differential upregulation of inflammatory mediators (IL1B, IL6, TNF, IFNG and IL10) in the initial segment and cauda epididymis within 72 h post-treatment. These changes were accompanied by a time-dependent endotoxin clearance from the epididymis. In the initial segment, interstitial LPS upregulated all centromeric (Slpi, Wfdc5, Wfdc12, Wfdc15a and Wfdc15b) and five telomeric (Wfdc2, Wfdc3, Wfdc6b, Wfdc10 and Wfdc13) Wfdc transcripts at 24 and 72 h. In the cauda epididymis, intravasal LPS upregulated Wfdc5 and Wfdc2 transcripts at 24 h, followed by a downregulation of Wfdc15b and three telomeric (Wfdc6a, Wfdc11, Wfdc16) gene transcripts at 72 h. Pharmacological inhibition of NFKB activation prevented LPS-induced upregulation of centromeric and telomeric Wfdc genes depending on the epididymal region. We show that LPS-induced inflammation differentially regulated the Wfdc locus in the proximal and distal epididymis, indicating region-specific roles for the Wfdc family in innate immune responses during epididymitis.
