Changes in expression levels of Nod-like receptors in the spleen of ewes

Abstract

Nucleotide-binding oligomerization domain receptors (NOD-like receptors, NLRs) have critical effects on interfaces of the immune and reproductive systems, and the spleen plays a key role in both innate and adaptive immune functions. It is hypothesized that NLR family participates in maternal splenic immune regulation during early pregnancy in sheep. In this study, maternal spleens were collected on day 16 of the estrous cycle, and days 13, 16 and 25 of gestation (n = 6 for each group) in ewes. Expression of NLR family, including NOD1, NOD2, class II transactivator (CIITA), NLR family apoptosis inhibitory protein (NAIP), nucleotide-binding oligomerization domain, Leucine rich repeat and Pyrin domain containing 1 (NLRP1), NLRP3 and NLRP7, was analyzed using quantitative real-time PCR, Western blot and immunohistochemistry analysis. The results revealed that expression levels of NOD1, NOD2, CIITA and NLRP3 were downregulated at days 13 and 16 of pregnancy, but expression of NLRP3 was increased at day 25 of pregnancy. In addition, expression values of NAIP and NLRP7 mRNA and proteins were improved at days 16 and 25 of pregnancy, and NLRP1 was peaked at days 13 and 16 of pregnancy in the maternal spleen. Furthermore, NOD2 and NLRP7 proteins were limited to the capsule, trabeculae and splenic cords. In summary, early pregnancy changes expression of NLR family in the maternal spleen, which may be related with the maternal splenic immunomodulation during early pregnancy in sheep.

Effects of early pregnancy on NOD-like receptor expression in the ovine endometrium

“…NOD1 and NOD2 signaling modulate metabolic, autoimmune, and inflammatory diseases, which is mediated by nuclear factor-κB (NF-κB) signaling, interferon mitogen-associated protein kinase signaling, and inflammasome activation (13). Our previous studies have reported that early pregnancy regulated the expression of the NLR family in the spleen, liver, thymus, and lymph nodes of ewes in a tissue-specific manner, which were involved in modulating maternal immune responses (14)(15)(16)(17). It was hypothesized that the expression of the NLR family in the ovine endometrium was modified by early pregnancy via IFNT and P 4 , which may be implicated in regulating maternal endometrial immune responses and contributing to pregnancy establishment.…”