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Poultry Science Jun 2024Mycoplasma gallisepticum (MG) can cause chronic respiratory disease (CRD) in chickens, which has a significant negative economic impact on the global poultry sector....
Mycoplasma gallisepticum (MG) can cause chronic respiratory disease (CRD) in chickens, which has a significant negative economic impact on the global poultry sector. Respiratory flora is the guardian of respiratory health, and its disorder is closely related to respiratory immunity and respiratory diseases. As a common probiotic in the chicken respiratory tract, Lactobacillus salivarius (L. salivarius) has potential antioxidant, growth performance enhancing, and anti-immunosuppressive properties. However, the specific mechanism through which L. salivarius protects against MG infection has not yet been thoroughly examined. This study intends to investigate whether L. salivarius could reduce MG-induced tracheal inflammation by modulating the respiratory microbiota and metabolites. The results indicated that L. salivarius reduced MG colonization significantly and alleviated the anomalous morphological changes by using the MG-infection model. L. salivarius also reduced the level of Th1 cell cytokines, increased the level of Th2 cell cytokines, and ameliorated immune imbalance during MG infection. In addition, L. salivarius improved the mucosal barrier, heightened immune function, and suppressed the Janus kinase/Signal transducer, and activator of transcription (JAK/STAT) signaling pathway. Notably, MG infection changed the composition of the respiratory microbiota and metabolites, and L. salivarius therapy partially reversed the aberrant respiratory microbiota and metabolite composition. Our results highlighted that these findings demonstrated that L. salivarius played a role in MG-mediated inflammatory damage and demonstrated that L. salivarius, by altering the respiratory microbiota and metabolites, could successfully prevent MG-induced inflammatory injury in chicken trachea.
PubMed: 38908119
DOI: 10.1016/j.psj.2024.103942 -
Fish Physiology and Biochemistry Jun 2024The current research aimed to shed light on the efficacy of Escherichia coli strain Nissle 1917 (EcN) on goldfish (……) growth, gut immunity, morphology, bacterial...
The current research aimed to shed light on the efficacy of Escherichia coli strain Nissle 1917 (EcN) on goldfish (……) growth, gut immunity, morphology, bacterial nutritional enzyme activity and resistance to Aeromonas hydrophila infection. Fish fed with EcN at 10, 10 and 10 CFU/g feed for 80 days showed an enhancement in growth better than control fish. The gut innate immunity in terms of lysozyme activity, immunoglobulin and total protein levels was increased in the treatment fish with the best result being observed in fish fed EcN at 10 CFU/ g. In addition, an increase was noted in the upregulation of immune-relevant genes, namely lysozyme, interleukin-1β, inducible nitric oxide synthase and tumor necrosis factor α of fish intestine. A marked surge in the number of proteolytic and heterotrophic bacteria was noted in the gut of fish nourished with the probiotic. Histological studies exhibited an improvement in the intestinal absorption surface area, intraepithelial lymphocyte count and goblet cell density. Significantly higher survival rate was obtained in fish fed EcN at 10 CFU/g compared with the fish fed with the basal diet. These data exhibited the beneficial effect of EcN on goldfish growth, digestive enzymes, intestine heterotrophic bacteria and resistance against Aeromonas hydrophila challenge. This study confirmed the favorable outcomes resulting from the administration of EcN at10 CFU/g.
PubMed: 38907742
DOI: 10.1007/s10695-024-01366-x -
BMC Nephrology Jun 2024IgA nephropathy, presently recognized as the foremost primary glomerular disorder, emerges as a principal contributor to renal failure globally, with its pathogenesis... (Review)
Review
IgA nephropathy, presently recognized as the foremost primary glomerular disorder, emerges as a principal contributor to renal failure globally, with its pathogenesis yet to be fully elucidated. Extensive research has highlighted the critical role of gut microbiome in the onset and progression of IgA nephropathy, underscoring its importance in accurately delineating the disease's etiology. For example, gut microbiome dysbacteriosis can lead to the production of nephritogenic IgA1 antibodies, which form immune complexes that deposit in the kidneys, causing inflammation and damage. The gut microbiome, a source of numerous bioactive compounds, interacts with the host and plays a regulatory role in gut-immune axis modulation, earning it the moniker of the "second brain." Recent investigations have particularly emphasized a significant correlation between IgA nephropathy and gut microbiome dysbacteriosis. This article offers a detailed overview of the pathogenic mechanisms of IgA nephropathy, specifically focusing on elucidating how alterations in the gut microbiome are associated with anomalies in the intestinal mucosal system in IgA nephropathy. Additionally, it describes the possible influence of gut microbiome on recurrent IgA nephropathy following kidney transplantation. Furthermore, it compiles potential therapeutic interventions, offering both theoretical and practical foundations for the management of IgA nephropathy. Lastly, the challenges currently faced in the therapeutic approaches to IgA nephropathy are discussed.
Topics: Glomerulonephritis, IGA; Humans; Gastrointestinal Microbiome; Dysbiosis; Immunity, Mucosal; Intestinal Mucosa; Kidney Transplantation
PubMed: 38907188
DOI: 10.1186/s12882-024-03646-3 -
Fish & Shellfish Immunology Jun 2024The development of green aquaculture practices has led to the supplementation of fish diets with natural immunostimulants such as organic acids. This study aimed to...
Immunostimulatory effects of dietary verjuice (Vitis vinifera) on immune response and transcription of immune-related genes in juvenile rainbow trout (Oncorhynchusmykiss).
The development of green aquaculture practices has led to the supplementation of fish diets with natural immunostimulants such as organic acids. This study aimed to assess the dietary effects of verjuice (VJ; unfermented unripe grapes; Vitis vinifera) on hematological parameters, skin mucosal immunity, transcriptional immune responses, and antibacterial serum activity against Aeromonas hydrophila in rainbow trout. The fish (51.0 ± 2.4 g) were randomly distributed into 15 tanks and fed ad-libitum thrice daily with diets containing different levels of VJ including 0 (control; VJ-0), 3 (VJ-3), 6 (VJ-6), 9 (VJ-9), and 12 (VJ-12) mL/kg VJ for 56 d. Results showed that immuno-hematological parameters (total white blood cells, neutrophils, and monocytes) were improved in VJ-added groups (P < 0.05). In addition, dietary VJ (9 mL/kg) modulated serum immunological parameters. Skin mucus immunology exhibited a notable increase in alkaline phosphatase, lysozyme activity, alkaline protease, total protein, total immunoglobulin, and esterase levels in VJ-9 group compared with those in the control group (P < 0.05). The mRNA expression of interleukin-1β, interleukin-6, interleukin-8, and immunoglobulin M were significantly higher in VJ-9 group than in the control (P < 0.05). Furthermore, the results of the antibacterial evaluation showed that A. hydrophila growth was significantly inhibited in the serum samples from VJ-3 to VJ-9 groups after the 56th day and in all VJ-treated groups after the 70th (P < 0.05). In conclusion, dietary VJ is a novel immunostimulant and the optimal dietary supplementation level of 6.65-7.46 mL/kg can effectively improve immune responses in rainbow trout.
PubMed: 38906438
DOI: 10.1016/j.fsi.2024.109714 -
Ecotoxicology and Environmental Safety Jun 2024Hydrogen sulphide (HS) is considered an immunotoxicant, and its presence in the water can influence the mucosal barrier functions of fish. However, there is a...
Hydrogen sulphide (HS) is considered an immunotoxicant, and its presence in the water can influence the mucosal barrier functions of fish. However, there is a significant knowledge gap on how fish mucosa responds to low environmental HS levels. The present study investigated the consequences of prolonged exposure to sub-lethal levels of HS on the mucosal defences of Atlantic salmon (Salmo salar). Fish were continuously exposed to two levels of HS (low: 0.05 µM; and high: 0.12 µM) for 12 days. Unexposed fish served as control. Molecular and histological profiling focused on the changes in the skin, gills and olfactory rosette. In addition, metabolomics and proteomics were performed on the skin and gill mucus. The gene expression profile indicated that the gills and olfactory rosette were more sensitive to HS than the skin. The olfactory rosette showed a dose-dependent response, but not the gills. Genes related to stress responses were triggered at mucosal sites by HS. Moreover, HS elicited strong inflammatory responses, particularly in the gills. All mucosal organs demonstrated the key molecular repertoire for sulphide detoxification, but their temporal and spatial expression was not substantially affected by sub-lethal HS levels. Mucosal barrier integrity was not considerably affected by HS. Mucus metabolomes of the skin and gills were unaffected, but a matrix-dependent response was identified. Comparing the high-concentration group's skin and gills mucus metabolomes identified altered amino acid biosynthesis and metabolism pathways. The skin and gill mucus exhibited distinct proteomic profiles. Enrichment analysis revealed that proteins related to immunity and metabolism were affected in both mucus matrices. The present study expands our knowledge of the defence mechanisms against HS at mucosal sites in Atlantic salmon. The findings offer insights into the health and welfare consequences of sub-lethal HS, which can be incorporated into the risk assessment protocols in salmon land-based farms.
PubMed: 38905940
DOI: 10.1016/j.ecoenv.2024.116617 -
Science Immunology Jun 2024Intestinal inflammation shifts microbiota composition and metabolism. How the host monitors and responds to such changes remains unclear. Here, we describe a protective...
Intestinal inflammation shifts microbiota composition and metabolism. How the host monitors and responds to such changes remains unclear. Here, we describe a protective mechanism by which mucosal-associated invariant T (MAIT) cells detect microbiota metabolites produced upon intestinal inflammation and promote tissue repair. At steady state, MAIT ligands derived from the riboflavin biosynthesis pathway were produced by aerotolerant bacteria residing in the colonic mucosa. Experimental colitis triggered luminal expansion of riboflavin-producing bacteria, leading to increased production of MAIT ligands. Modulation of intestinal oxygen levels suggested a role for oxygen in inducing MAIT ligand production. MAIT ligands produced in the colon rapidly crossed the intestinal barrier and activated MAIT cells, which expressed tissue-repair genes and produced barrier-promoting mediators during colitis. Mice lacking MAIT cells were more susceptible to colitis and colitis-driven colorectal cancer. Thus, MAIT cells are sensitive to a bacterial metabolic pathway indicative of intestinal inflammation.
Topics: Animals; Mucosal-Associated Invariant T Cells; Colitis; Dysbiosis; Mice; Gastrointestinal Microbiome; Mice, Inbred C57BL; Mice, Knockout; Intestinal Mucosa; Riboflavin
PubMed: 38905325
DOI: 10.1126/sciimmunol.adi8954 -
Discovery Immunology 2024Direct interaction between T-cells exerts a major influence on tissue immunity and inflammation across multiple body sites including the human gut, which is highly...
Direct interaction between T-cells exerts a major influence on tissue immunity and inflammation across multiple body sites including the human gut, which is highly enriched in 'unconventional' lymphocytes such as γδ T-cells. We previously reported that microbial activation of human Vγ9/Vδ2 γδ T-cells in the presence of the mucosal damage-associated cytokine IL-15 confers the ability to promote epithelial barrier defence, specifically via induction of IL-22 expression in conventional CD4 T-cells. In the current report, we assessed whether other cytokines enriched in the gut milieu also functionally influence microbe-responsive Vγ9/Vδ2 T-cells. When cultured in the presence of IL-21, Vγ9/Vδ2 T-cells acquired the ability to induce expression of the immunoregulatory cytokine IL-10 in both naïve and memory CD4 T-cells, at levels surpassing those induced by monocytes or monocyte-derived DCs. These findings identify an unexpected influence of IL-21 on Vγ9/Vδ2 T-cell modulation of CD4 T-cell responses. Further analyses suggested a possible role for CD30L and/or CD40L reverse signalling in mediating IL-10 induction by IL-21 conditioned Vγ9/Vδ2 T-cells. Our findings indicate that the local microenvironment exerts a profound influence on Vγ9/Vδ2 T-cell responses to microbial challenge, leading to induction of distinct functional profiles among CD4 T-cells that may influence inflammatory events at mucosal surfaces. Targeting these novel pathways may offer therapeutic benefit in disorders such as inflammatory bowel disease.
PubMed: 38903247
DOI: 10.1093/discim/kyae008 -
reshapes mucosal immunity toward a Type 2 response that attenuates inflammatory bowel-like diseases.BioRxiv : the Preprint Server For... Mar 2024Diarrheal diseases are the second leading cause of death in children worldwide. Epidemiological studies show that co-infection with decreases the severity of diarrhea....
Diarrheal diseases are the second leading cause of death in children worldwide. Epidemiological studies show that co-infection with decreases the severity of diarrhea. Here, we show that is highly prevalent in the stools of asymptomatic school-aged children. It orchestrates a Th2 mucosal immune response, characterized by increased antigen-specific Th2 cells, IL-25, Type 2-associated cytokines, and goblet cell hyperplasia. infection expanded IL-10-producing Th2 and GATA3 Treg cells that promoted chronic carriage, parasite transmission, and conferred protection against -induced lethal ileitis and DSS-driven colitis by downregulating proinflammatory cytokines, decreasing Th1/Th17 cell frequency, and preventing collateral tissue damage. Protection was dependent on STAT6 signaling, as -infected STAT6 mice no longer regulated intestinal bystander inflammation. Our findings demonstrate that infection reshapes mucosal immunity toward a Type 2 response, which confers a mutualistic protection against inflammatory disease processes and identifies a critical role for protists in regulating mucosal defenses.
PubMed: 38903060
DOI: 10.1101/2024.03.02.583119 -
Mucosal Immunology Jun 2024Exaggeration of type 2 immune responses promotes lung inflammation and altered lung development; however, eosinophils, despite expansion in the postnatal lung, have not...
Exaggeration of type 2 immune responses promotes lung inflammation and altered lung development; however, eosinophils, despite expansion in the postnatal lung, have not been specifically assessed in the context of neonatal lung disease. Furthermore, early-life factors including prematurity and respiratory infection predispose infants to chronic obstructive pulmonary disease later in life. To assess eosinophils in the developing lung and how they may contribute to chronic lung disease, we generated mice harboring eosinophil-specific deletion of the negative regulatory enzyme SHIP-1. This increased the activity and number of pulmonary eosinophils in the developing lung, which was associated with impaired lung development, expansion of activated alveolar macrophages (AMφ), multinucleated giant cell formation, enlargement of airspaces, and fibrosis. Despite regression of eosinophils following completion of lung development, AMφ-dominated inflammation persisted, alongside lung damage. Bone marrow chimera studies showed that SHIP-1-deficient eosinophils were not sufficient to drive inflammatory lung disease in adult steady-state mice but once inflammation and damage was present, it could not be resolved. Depletion of eosinophils during alveolarization alleviated pulmonary inflammation and lung pathology, demonstrating an eosinophil-intrinsic effect. These results show that the presence of activated eosinophils during alveolarization aggravates AMφs and promotes sustained inflammation and long-lasting lung pathology.
PubMed: 38901764
DOI: 10.1016/j.mucimm.2024.06.003 -
The ISME Journal Jun 2024Probiotics have gained significant attention as a potential strategy to improve health by modulating host-microbe interactions, particularly in situations where the...
Probiotics have gained significant attention as a potential strategy to improve health by modulating host-microbe interactions, particularly in situations where the normal microbiota has been disrupted. However, evidence regarding their efficacy has been inconsistent, with considerable inter-individual variability in response. We aimed to explore whether a common genetic variant that affects the production of mucosal α(1,2)-fucosylated glycans, present in around 20% of the population, could explain the observed interpersonal differences in the persistence of commonly used probiotics. Using a mouse model with varying α(1,2)-fucosylated glycans secretion (Fut2WT or Fut2KO), we examined the abundance and persistence of Bifidobacterium strains (infantis, breve, and bifidum). We observed significant differences in baseline gut microbiota characteristics between Fut2WT and Fut2KO littermates, with Fut2WT mice exhibiting enrichment of species able to utilise α(1,2)-fucosylated glycans. Following antibiotic exposure, only Fut2WT animals showed persistent engraftment of Bifidobacterium infantis, a strain able to internalise α(1,2)-fucosylated glycans, whereas B. breve and Bifidobacterium bifidum, which cannot internalise α(1,2)-fucosylated glycans, did not exhibit this difference. In mice with an intact commensal microbiota, the relationship between secretor status and B. infantis persistence was reversed, with Fut2KO animals showing greater persistence compared to Fut2WT. Our findings suggest that the interplay between a common genetic variation and antibiotic exposure plays a crucial role in determining the dynamics of B. infantis in the recipient gut, which could potentially contribute to the observed variation in response to this commonly used probiotic species.
PubMed: 38896583
DOI: 10.1093/ismejo/wrae107