Global Transcriptomic Profiling of Bovine Endometrial Immune Response In Vitro. I. Effect of Lipopolysaccharide on Innate Immunity1

Abstract

The dysregulation of endometrial immune response to bacterial lipopolysaccharide (LPS) has been implicated in uterine disease and infertility in the postpartum dairy cow, although the mechanisms are not clear. Here, we investigated whole-transcriptomic gene expression in primary cultures of mixed bovine epithelial and stromal endometrial cells. Cultures were exposed to LPS for 6 h, and cellular response was measured by bovine microarray. Approximately 30% of the 1006 genes altered by LPS were classified as being involved in immune response. Cytokines and chemokines (IL1A, CX3CL1, CXCL2, and CCL5), interferon (IFN)-stimulated genes (RSAD2, MX2, OAS1, ISG15, and BST2), and the acute phase molecule SAA3 were the most up-regulated genes. Ingenuity Pathway Analysis identified up-regulation of many inflammatory cytokines and chemokines, which function to attract immune cells to the endometrium, together with vascular adhesion molecules and matrix metalloproteinases, which can facilitate immune cell migration from the tissue toward the uterine lumen. Increased expression of many IFN-signaling genes, immunoproteasomes, guanylate-binding proteins, and genes involved in the intracellular recognition of pathogens suggests important roles for these molecules in the innate defense against bacterial infections. Our findings confirmed the important role of endometrial cells in uterine innate immunity, whereas the global approach used identified several novel immune response pathways triggered by LPS in the endometrium. Additionally, many genes involved in endometrial response to the conceptus in early pregnancy were also altered by LPS, suggesting one mechanism whereby an ongoing response to infection may interfere with the establishment of pregnancy.

Bovine Endometrial Cells Mount Innate Immune Response to the Intracellular Ligands CL097 and Poly(dA:dT) Indicating Roles against Uterine Viruses

“…in agreement with previous findings [18] [20], as well as the cytosolic PRRs IFIH1 [21], DDX58 and LRRFIP1. These receptors have important roles in detecting both extracellular and intracellular pathogens during innate immunity.…”

“…We previously showed peak expression of TNF at 1 h after treatment of BEESC with LPS although the peak response to IL1B was at 6 h [20] so it is possible that a peak cytokine response to poly(dA:dT) had occurred earlier than the first time of assessment. These key inflammatory cytokines are an important component of the early innate immune defence [21] and also serve as a crucial link in the development of an adaptive immune response [33]. TLR7/8 agonists also up-regulated many cytokine genes and proteins in human DCs [35].…”

Regulation of inflammatory mediator expression in bovine endometrial cells: effects of lipopolysaccharide, interleukin 1 beta, and tumor necrosis factor alpha

“…To evaluate the effects of an infectious agent and inflammatory mediators on the gene expression and cytokine production of endometrial cells, the endometrial epithelial cells (bEEL, seeded at 35 000 cells per well) and stromal (bCSC, seeded at 8000 cells per well) were cultured in a 24‐well culture plates (Corning Costar) supplemented with RPMI media containing bacterial lipopolysaccharide (LPS, 1 μ g/mL; O111:B4; catalogue number L2630; Sigma‐Aldrich, St. Louis, MO, USA), bovine IL‐1 β (10 ng/mL; catalogue number RBOIL1BI; Thermo Scientific; Frederick, MD, USA), bovine TNF α (50 ng/mL; catalogue number RPB‐341; IBI Scientific, Peosta, IA, USA) or untreated cells (vehicle control) for 6 h and 24 h. The time of 6 h was chosen based on time‐course studies in endometrium which previously had shown to induces changes in inflammatory genes (e.g., CXCL8/IL8, IL1B, IL6 and/or fatty acid cyclooxygenase‐2) that peaked by 6 h following the treatment with LPS (Oguejiofor et al. ; Swangchan‐Uthai et al. ), IL‐1 β (Huang et al.…”

“…; Oguejiofor et al. ; Swangchan‐Uthai et al. ) have focused on the characterization of the inflammatory response triggered by infectious agents.…”

Bovine P-selectin mediates leukocyte adhesion and is highly polymorphic in dairy breeds

“…Similar to mastitis, there is evidence for the involvement of selectins in all of these processes. Both SELP and SELL are significantly upregulated in endometrial cells stimulated with the bacterial product lipopolysaccharide (LPS) (Oguejiofor et al, 2015). SELP is also crucial for the migration of PMN into the bovine corpus luteum during luteolysis (Shirasuna et al, 2012).…”