Transcriptome Analysis Revealed Ameliorative Effects of Bacillus Based Probiotic on Immunity, Gut Barrier System, and Metabolism of Chicken under an Experimentally Induced Eimeria tenella Infection

Abstract

In this study, we performed transcriptome analysis in the cecum tissues of negative control untreated non-challenged (NC), positive control untreated challenged (PC), and Bacillus subtilis (B. subtilis) fed challenged chickens (BS + ET) in order to examine the underlying potential therapeutic mechanisms of Bacillus based probiotic feeding under an experimental Eimeria tenella (E. tenella) infection. Our results for clinical parameters showed that birds in probiotic diet decreased the bloody diarrhea scores, oocyst shedding, and lesion scores compared to positive control birds. RNA-sequencing (RNA-seq) analysis revealed that in total, 2509 up-regulated and 2465 down-regulated differentially expressed genes (DEGs) were detected in the PC group versus NC group comparison. In the comparison of BS + ET group versus PC group, a total of 784 up-regulated and 493 down-regulated DEGs were found. Among them, several DEGs encoding proteins involved in immunity, gut barrier integrity, homeostasis, and metabolism were up-regulated by the treatment of probiotic. Functional analysis of DEGs also revealed that some gene ontology (GO) terms related with immunity, metabolism and cellular development were significantly affected by the exposure of probiotic. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis showed that the DEGs in the cecum of B. subtilis-fed challenged group were mainly participated in the pathways related with immunity and gut barrier integrity, included mitogen-activated protein kinase (MAPK) signaling pathway, toll-like receptor (TLR) signaling pathway, extracellular matrix (ECM)–receptor interaction, tight junction, and so on. Taken together, these results suggest that Bacillus based probiotic modulate the immunity, maintain gut homeostasis as well as barrier system and improve chicken metabolism during E. tenella infection.

Effect of bacillus subtilis strain Z15 secondary metabolites on immune function in mice

“…Probiotics are microorganisms that are beneficial to the health of the host and stimulate the innate and adaptive immune systems [ 4 , 5 ]. Bacillus subtilis is one of the main sources of probiotics and is classified as GRAS (Generally Recognized as Safe) by the US Food and Drug Administration (FDA).…”

Transcriptional changes in LMH cells induced by Eimeria tenella rhoptry kinase family protein 17

“…This indicated that EtROP17 may play a crucial role in parasite replication within chicken intestinal epithelial cells. Moreover, the cell to ECM interaction can form physical barriers to prevent invasion of pathogens ( 35 ). This indicated that, besides affecting intestinal immune network for IgA production, EtROP17 may contribute to defense against microbial infections through affecting ECM-receptor interaction.…”

Effect of Bacillus subtilis strain Z15 secondary metabolites on immune function in mice

“…This study was enriched by blood transcriptomic analysis of changes in the expression of genes related to the TLR signaling pathway, response to interferon-β, tumor necrosis factor signaling pathway, systemic lupus erythematosus, and primary immunode ciency. TLRs are a type of PRR that recognize pathogenassociated molecular patterns (PAMPs) in different microorganisms and act as a bridge between the innate and adaptive immune systems (26), activating multiple signaling pathways in immune cells and thus, providing a defense mechanism against pathogens (5). TLR2-TLR1 or TLR2-TLR6 heterodimers recognize different pathogen-expressed PAMPs including lipoproteins, peptidoglycans and yeast glycans (27).…”

“…Probiotics are microorganisms that are bene cial to the health of the host and stimulate the innate and adaptive immune systems (4,5). Bacillus subtilis is one of the main sources of probiotics and is classi ed as GRAS (Generally Recognized as Safe) by the US Food and Drug Administration (FDA).…”