Host-microbiota interaction-mediated resistance to inflammatory bowel disease in pigs

BACKGROUND

Disease resistance phenotypes are associated with immune regulatory functions and immune tolerance and have implications for both the livestock industry and human health. Microbiota plays an essential role in regulating immunity and autoimmunity in the host organism, but the influence of host-microbiota interactions on disease resistance phenotypes remains unclear. Here, multiomics analysis was performed to identify potential regulatory mechanisms of disease resistance at both the microbiome and host levels in two pig breeds.

RESULTS

Acute colitis models were established in Min pigs and Yorkshire pigs, and control and diseased individuals were compared. Compared with Yorkshire pigs under the same nutritional and management conditions, Min pigs exhibited strong disease resistance, as indicated by a low disease activity index (DAI) and a low histological activity index (HAI). Microbiota sequencing analysis showed that potentially harmful microbes Desulfovibrio, Bacteroides and Streptococcus were enriched in diseased individuals of the two breeds. Notably, potentially beneficial microbes, such as Lactobacillus, Clostridia and Eubacterium, and several genera belonging to Ruminococcaceae and Christensenellaceae were enriched in diseased Min pigs and were found to be positively associated with the microbial metabolites related to intestinal barrier function. Specifically, the concentrations of indole derivatives and short-chain fatty acids were increased in diseased Min pigs, suggesting beneficial action in protecting intestinal barrier. In addition, lower concentrations of bile acid metabolites and short-chain fatty acids were observed in diseased Yorkshire pigs, which were associated with increased potentially harmful microbes, such as Bilophila and Alistipes. Concerning enrichment of the immune response, the increase in CD4⁺ T cells in the lamina propria improved supervision of the host immunity response in diseased Min pigs, contributing to the maintenance of Th2-type immune superiority and immune tolerance patterns and control of excessive inflammation with the help of potentially beneficial microbes. In diseased Yorkshire pigs, more terms belonging to biological processes of immunity were enriched, including Toll-like receptors signalling, NF-κB signalling and Th1 and Th17-type immune responses, along with the increases of potentially harmful microbes and damaged intestinal barrier.

CONCLUSIONS

Cumulatively, the results for the two pig breeds highlight that host-microbiota crosstalk promotes a disease resistance phenotype in three ways: by maintaining partial PRR nonactivation, maintaining Th2-type immune superiority and immunological tolerance patterns and recovering gut barrier function to protect against colonic diseases. Video abstract.

Correlation between immune response and self-reported depression during convalescence from COVID-19

Self-reported depression has been observed in coronavirus disease-2019 (COVID-19) patients, infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), during discharge from the hospital. However, the cause of this self-reported depression during the convalescent period remains unclear. Here, we report the mental health status of 96 convalescent COVID-19 patients who were surveyed using an online questionnaire at the Shenzhen Samii Medical Center from March 2 to March 12, 2020 in Shenzhen, China. After obtaining their informed consent, we retrospectively analyzed the clinical characteristics of patients, including routine blood and biochemical data. The results suggested that patients with self-reported depression exhibited increased immune response, as indicated by increased white blood cell and neutrophil counts, as well as neutrophil-to-lymphocyte ratio. However, the mechanism linking self-reported depression to these cellular changes needs further study. In conclusion, self-reported depression occurred at an early stage in convalescent COVID-19 patients, and changes in immune function were apparent during short-term follow-up of these patients after discharge. Appropriate psychological interventions are necessary, and changes in immune function should be emphasized during long-term follow up of these patients.

Toxicity of some insecticides to the haemocytes of giant honeybee, Apis dorsata F. under laboratory conditions

Quantitative studies concerning total and differential haemocyte counts and abnormalities were performed under laboratory conditions for larvae, pupae and adults collected from a wild Apis dorsata colony. Haemolymph samples were observed immediately, thirty and sixty minutes after field recommended concentration exposure of five different insecticides. Total haemocyte counts were significantly higher for larvae and pupae but less for adult bees, however, differential haemocyte counts insignificantly different. Exposure of insecticides showed variable response for tested insecticides with immediate increased change with ethofenprox, diafenthiuron and imidacloprid but decreased for all tested insecticides after sixty minutes. For differential haemocyte counts, plasmatocytes and granulocytes increased with exposure of insecticides. Immune response of haemocytes against insecticides showed different degrees of abnormalities like agglutination, denucleation and cell shape distortion. Such studies may help in possible identification of insect defense mechanisms against their exposure to external hazards for instance insecticide exposure.

Effects of light intensity on growth, immune responses, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala

Light is necessary for many fish species to develop and grow normally since most fishes are visual feeders. However, too intense light may be stressful or even lethal. Thus, this study was conducted to evaluate the effect of light intensity on growth, immune response, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala. Fish (18.04 ± 0.22 g) randomly divided into 5 groups were exposed to a range of light intensities (100, 200, 400, 800 and 1600 lx) in cultures for 8 weeks. After the feeding trial, fish were challenged by Aeromonas hydrophila and cumulative mortality was recorded for the next 96 h. The results demonstrated that fish subjected to 400 lx showed the greatest weight gain (125.70 ± 5.29%). Plasma levels of glucose and lactate increased with light intensity rising from 100 lx to 1600 lx while the lowest plasma levels of cortisol was observed at 400 lx group. Post-challenged haemato-immunological parameters (including plasma lysozyme and alternative complement activities, as well as plasma nitric oxide level and globulin contents) improved with light intensity increasing from 100 lx to 400 lx, and then decreased with further increasing light intensity. However, antioxidant biomarkers such as liver catalase and malondialdehyde showed an opposite trend with immune response with the lowest values observed at 400 lx groups. The application of light intensity at 1600 lx significantly lowered liver glutathione activity to 76.78 ± 6.91 μmol g(-1). Within a range of light intensity from 100 to 400 lx, no differences were observed in liver total superoxide dismutase and glutathione peroxidase activities while they were significantly higher at 800 and 1600 lx. After challenge, the lowest mortality was observed in fish exposed to 400 lx. It was significantly lower than that of fish exposed to 100 and 1600 lx. The results of the present study indicated that high light intensities (more than 800 lx) not only produced poor growth, but also led to stress response, as might consequently result in the elevated liver oxidation rates and depress immunity of this species. Although no stress response was observed, fish subjected to low light intensities (lower than 400 lx) also showed oxidative stress, immunosuppression and reduced disease resistance. Taken together, the optimal light intensity to enhance growth and boost immunity of this species at juvenile stage is 400 lx.

Effects of perfluorooctane sulfonate on the immune responses and expression of immune-related genes in Chinese mitten-handed crab Eriocheir sinensis

Perfluorooctane sulfonate (PFOS) has been widely studied due to its global distribution, slow degradation, high bioaccumulation and toxicological effects on vertebrates. However, the potential toxicity of PFOS to crustaceans is little known. The present study investigated the effects of PFOS on the immune responses and expression of immune-related genes in the Chinese mitten-handed crab Eriocheir sinensis. Crabs were exposed to 0, 0.01, 0.1, 1.0 and 10mg/L of PFOS, and sampled on 1, 4, 7, 14 and 21days respectively. The total hemocyte count and lysozyme activity in PFOS-treated crab were significantly lower than in the control. The exposure to 10mg/L of PFOS led to a marked inhibition in phenoloxidase and superoxide dismutase activities. At other PFOS levels, phenoloxidase and superoxide dismutase showed an initial increase and a subsequent decrease over time. The alkaline and acid phosphatase activities were stimulated in 10mg/L PFOS until 21days. The mRNA expression of immune related genes including hepatopancreas-specific C-type lectin and prophenoloxidase activating factors were up-regulated after the exposure to the concentrations of 1 and 10mg/L of PFOS, while the expression of lysozyme gene was up-regulated only in the crab exposed to 0.1mg/L PFOS. The results demonstrate that the high dose of PFOS leads to immune toxicity and the hepatopancreas is a major target organ for PFOS accumulation and immunotoxicity. Hemocyte counts, phenoloxidase and acid phosphatase are useful biomarkers for the risk assessment of PFOS toxicity to crustaceans.

Response of Sabella spallanzanii to multiple stressors. The combined effect of infection and copper sulphate

The aim of this work is to study the immune responses of the polychaete Sabella spallanzanii after exposure to copper sulphate, an immunomodulating agent in marine organisms, and the multiple stresses caused by Escherichia coli infection, to validate the species as a model organism in marine-coastal biomonitoring programmes. Polychaetes were housed in laboratory and divided into five experimental groups: 1. Control (no microinjected), 2. filtered seawater + TBS injection (control of point 3), 3. filtered seawater + E. coli injection (control of point 4), 4. CuSO₄ + TBS injection (control of point 5), and 5. CuSO₄ + E. coli injection. The immune variables, esterase and alkaline phosphatase activity, cytotoxicity and detoxifying/antioxidant enzymes such as glutathione peroxidase were evaluated in total body extracts of the animals. Moreover, toll-like receptor, allograft inflammatory factor-1, lysozyme and haemagglutinating activity were investigated to highlight possible interactions. Indeed, the results of this work demonstrate the immunomodulating effect of copper sulphate on S. spallanzanii total body extracts related to oxidative stress and inflammatory markers.

Pathogenicity and transcriptome analysis of a strain of Vibrio owensii in Fenneropenaeus merguiensis

Vibrio is an important conditional pathogen in shrimp aquaculture. This research reported a dominant bacteria strain E1 isolated from a shrimp tank with the method of biofloc culture, which was further identified as Vibrio owensii. To understand the interaction between V. owensii and the host shrimp, we studied the pathogenicity of the V. owensii and the molecular mechanisms of the Fenneropenaeus merguiensis immunity during the Vibrio invasion. Drug susceptibility tests showed that V. owensii was resistant to antibiotics streptomycin oxacillin, tetracycline, minocycline, and aztreonam, but highly sensitive to cefazolin, cefotaxime, and ciprofloxacin, and moderately sensitive to cefotaxime, ampicillin, and piperacillin. Lethal concentration 50 (LC₅₀) test was performed to evaluate the toxicity of V. owensii to F. merguiensis. The LC₅₀ of V. owensii infected F. merguiensis after 24, 48, 72, 96, 120, 144 and 168 h were 1.21 × 10⁷, 1.68 × 10⁶, 6.36 × 10⁵, 2.15 × 10⁵, 7.58 × 10⁴, 5.55 × 10⁴ and 4.33 × 10⁴ CFU/mL. In order to explore the molecular response mechanism of F. merguiensis infected with V. owensii, the hepatopancreas of F. merguiensis were sequenced at 24 hpi and 48 hpi, and a total 40,181 of unigenes were obtained. Through comparative transcriptomic analysis, 86 differentially expressed genes (DEGs) (including 38 up-regulated DEGs, and 48 down-regulated DEGs) and 305 DEGs (including 150 up-regulated DEGs, and 155 down-regulated DEGs) were identified at 24 hpi and 48 hpi, respectively. Annotation and classification analysis of these 391 DEGs showed that most of the DEGs were annotated to metableolic and immune pathways, which indicated that F. merguiensis responded to the invasion through the regulation of material metableolism and immune system genes during V. owensii infection. In the KEGG enrichment analysis, some pathways related to immune response were significantly influenced by V. owensii infection, including phagosome, MAPK signalling pathway and PI3K-Akt signalling pathway. In addition, some pathways related to the warburg effect were also significantly enriched after V. owensii infection, including pyruvate metableolism, glycolysis/gluconeogenesis, and citrate cycle (TAC cycle). Further analysis showed that C-type lectins and ficolin were also play important roles in the immune response of F. merguiensis against V. owensii infection. The current research preliminarily revealed the immune response of F. merguiensis to V. owensii infection at the molecular level, which provided valuable information to further understand the disease control and the interaction between shrimp and Vibrio.

Immune response of frontline medical workers providing medical support for Wuhan COVID-19 patients, China

The outbreak of novel coronavirus disease 2019 (COVID-19) posed a great challenge and stress to frontline medical workers in China. Stress is closely related to immunity. However, the immune response of frontline medical workers providing medical support for COVID-19 patients is unclear. Here, we reported the immune response of 76 frontline medical workers and 152 controls from the Second Affiliated Hospital of Xi'an Jiaotong University. The frontline medical workers were involved in the care for Wuhan COVID-19 patients from February 8 to March 31, 2020 in Tongji Hospital of Huazhong University of Science and Technology. The controls were medical workers of our hospital who had not been in contact with COVID-19 patients during the same period. Demographic and clinical data, including routine blood test data were extracted from the electronic health examination record and retrospectively analyzed. The post-stress frontline medical workers had higher lymphocyte (LYM) count compared with controls or pre-stress. However, the post-stress frontline medical workers had lower monocyte (MONO) count, neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR) and neutrophil (NEUT) ratio than controls or pre-stress. Interestingly, we found the differences were more significantly in female subgroup and nurse subgroup. Together, these data indicated that changes of immune response were found in frontline medical workers providing medical support for Wuhan COVID-19 patients, especially in females and nurses. Those maybe caused by psychological stress and we recommend to pay more attention to mental health of frontline medical workers, and provide appropriate psychological interventions for them.

Protective effects of butyric acid during heat stress on the survival, immune response, histopathology, and gene expression in the hepatopancreas of juvenile pacific shrimp (L. Vannamei)

This study looked at the effects of adding butyric acid (BA) to the diets of juvenile Pacific shrimp and how it affected their response to survival, immunity, histopathological, and gene expression profiles under heat stress. The shrimp were divided into groups: a control group with no BA supplementation and groups with BA inclusion levels of 0.5 %, 1 %, 1.5 %, 2 %, and 2.5 %. Following the 8-week feeding trial period, the shrimp endured a heat stress test lasting 1 h at a temperature of 38 °C. The results showed that the control group had a lower survival rate than those given BA. Interestingly, no mortality was observed in the group receiving 1.5 % BA supplementation. Heat stress had a negative impact on the activities of alkaline phosphatase (AKP) and acid phosphatase (ACP) in the control group. Still, these activities were increased in shrimp fed the BA diet. Similar variations were observed in AST and ALT fluctuations among the different groups. The levels of triglycerides (TG) and cholesterol (CHO) increased with high temperatures but were reduced in shrimp-supplemented BA. The activity of an antioxidant enzyme superoxide dismutase (SOD) increased with higher BA levels (P < 0.05). Moreover, the groups supplemented with 1.5 % BA exhibited a significant reduction in malondialdehyde (MDA) content (P < 0.05), suggesting the potential antioxidant properties of BA. The histology of the shrimp's hepatopancreas showed improvements in the groups given BA. Conversely, the BA significantly down-regulated the HSPs and up-regulated MnSOD transcript level in response to heat stress. The measured parameters determine the essential dietary requirement of BA for shrimp. Based on the results, the optimal level of BA for survival, antioxidant function, and immunity for shrimp under heat stress is 1.5 %.

Variation in the physiological response of adult worker bees of different ages (Apis mellifera L.) to pyraclostrobin stress

The social division of labor within the honeybee colony is closely related to the age of the bees, and the age structure is essential to the development and survival of the colony. Differences in tolerance to pesticides and other external stresses among worker bees of different ages may be related to their social division of labor and corresponding physiological states. Pyraclostrobin was widely used to control the fungal diseases of nectar and pollen plants, though it was not friend to honey bees and other pollinators. This work aimed to determine the effects of field recommended concentrations of pyraclostrobin on the activities of protective and detoxifying enzymes, on the expression of genes involved in nutrient metabolism, and immune response in worker bees of different ages determined to investigate the physiological and biochemical differences in sensitivity to pyraclostrobin among different age of worker bees. The result demonstrates that the tolerance of adult worker bees to pyraclostrobin was negatively correlated with their age, and the significantly reduced survival rate of forager bees (21 day-old) with continued fungicide exposure. The activities of protective enzymes (CAT and SOD) and detoxifying enzymes (CarE, GSTs and CYP450) in different ages of adult worker bees were significantly altered, indicating the physiological response and the regulatory capacity of worker bees of different ages to fungicide stress was variation. Compared with 1 and 8 day-old worker bees, the expression of nutrient-related genes (ilp1 and ilp2) and immunity-related genes (apidaecin and defensin1) in forager bees (21 day-old) was gradually downregulated with increasing pyraclostrobin concentrations. Moreover, the expression of vitellogenin and hymenoptaecin in forager bees (21 day-old) was also decreased in high concentration treatment groups (250 and 313 mg/L). The present study confirmed the findings of the chronic toxicity of pyraclostrobin on the physiology and biochemistry of worker bees of different ages, especially to forager bees (21 day-old). These results would provide important physiological and biochemical insight for better understanding the potential risks of pyraclostrobin on honeybees and other non-target pollinators.

Dynamics in a disease transmission model coupled virus infection in host with incubation delay and environmental effects

In this paper, a disease transmission model coupled virus infection in host with incubation delay and environmental effects is studied. For the virus infection model in host with immune, latent delay and environmental virus invading, the threshold criteria on the global stability of antibody-free and antibody response infection equilibria are established. For the disease transmission model with incubation delay and immune response in host, basic reproduction number R 0 is defined, and the local stability of equilibria are established, i.e., the disease-free equilibrium is locally asymptotically stable ifR 0 < 1 , and the endemic equilibrium is locally asymptotically stable ifR 0 > 1 . Furthermore, the uniform persistence of positive solutions is studied while there is not the direct transmission of disease by the infected individuals. Finally, the numerical examples are presented to verify the main results.

Alleviative effects of astragaloside IV on cyclophosphamide-induced oxidative damage and immunosuppression in tilapia (Oreochromis niloticus)

Astragaloside IV (ASIV) has effects of antioxidation and immunologic enhancement. However, there are few reports on the application and potential mechanism of ASIV in aquaculture. In this study, we investigated the effect of ASIV on growth, antioxidation, and immune function of tilapia. Tilapia were fed a diet containing 0.1, 0.2, and 0.5 g·kg^-1 ASIV for 60 days, followed by an intrapleural injection of 50 mg·kg^-1 cyclophosphamide (CTX) to induce oxidative damage and immunosuppression. Then tilapia were weighed and blood, liver, spleen, kidney, and intestinal were collected. The results showed ASIV increased the final weight, relative weight rate, and specific growth rate of tilapia, reduce conversion ratio, and reduced the morphological lesions of tissues. Meanwhile, ASIV alleviated CTX-induced oxidative damage by improving antioxidant activity in serum and tissues and inhibiting lipid peroxidation. Additionally, ASIV attenuated the immunosuppression of tilapia caused by CTX, regulated immunochemical indexes in serum, increased the viability of peripheral blood leukocytes and head kidney macrophages, and restored respiratory burst activity (O₂^-) in head kidney macrophages and splenocytes. Furthermore, qPCR data showed ASIV up-regulated antioxidant-related gene expression of nrf2, ho-1, gpx3, and cat and immune-related gene expression including C3 and igm. In conclusion, ASIV as a feed additive can not only improve the growth performance but also enhance the antioxidant capacity and immune function of tilapia, which may be associated with the ability of ASIV to scavenge free radicals, reduce lipid peroxidation levels, and stabilize numbers of immune cells.

The effects of ammonia stress exposure on protein degradation, immune response, degradation of nitrogen-containing compounds and energy metabolism of Chinese mitten crab

BACKGROUND

The Chinese mitten crab is one of the most economically important crabs that are widely farmed in China. Ammonia, which is a main physiological challenge for crab culture, grows rapidly in the intensive culture system over time, but little information is available with Chinese mitten crab on the molecular mechanisms.

METHODS AND RESULTS

Therefore, to understand the mechanism of response to ammonia stress in Eriocheir japonica sinensis, comparative transcriptome analysis was used to identify the key genes and pathways in hepatopancreas challenged with ammonia stress (325.07 mg/L NH4Cl). By sequencing the transcriptome hepatopancreas of E. j. sinensis treated with ammonia, 366,472 unigenes were obtained and annotated into several public libraries for later analyses. Subsequently, 1775 differentially expressed genes (DEGs) were identified according to comparative transcriptome analysis, of which 307 were up-regulated and 1468 were down-regulated. According to the DEGs of GO and KEGG enrichment analyses, we focused on four aspects of significant enrichment in this study: protein degradation, immune response, degradation of nitrogen-containing compounds and energy metabolism. The genes involved in protein degradation and energy metabolism process showed a significant decrease which was consisting of overall biological activity of E. j. sinensis decreased. In addition, five genes involved in high concentration of ammonia were discovered and validated by qRT-PCR.

CONCLUSIONS

This study will help us understand the molecular mechanisms of E. j. sinensis under high ammonia exposure and provide valuable information to the future research of other crabs with ammonia exposure.

Lacticaseibacillus chiayiensis mediate intestinal microbiome and microbiota-derived metabolites regulating the growth and immunity of chicks

Emerging evidence confirms beneficial properties of probiotics in promoting growth and immunity of farmed chicken. However, the molecular mechanisms underlying the host-microbiome interactions mediated by probiotics are not fully understood. In this study, the internal mechanisms of Lacticaseibacillus chiayiensis-mediated host-microbiome interactions and to elucidate how it promotes host growth were investigated by additional supplementation with L. chiayiensis. We conducted experiments, including intestinal cytokines, digestive enzymes test, intestinal microbiome, metabolome and transcriptome analysis. The results showed that chickens fed L. chiayiensis exhibited higher body weight gain and digestive enzyme activity, and lower pro-inflammatory cytokines, compared to controls. Microbiota sequencing analysis showed that the gut microbiota structure was reshaped with L. chiayiensis supplementation. Specifically, Lactobacillus and Escherichia increased in abundance and Enterococcus, Lactococcus, Corynebacterium, Weissella and Gallicola decreased. In addition, the bacterial community diversity was significantly increased compared to controls. Metabolomic and transcriptomic analyses revealed that higher bile acids and N-acyl amides concentrations and lower carbohydrates concentrations in L. chiayiensis-fed chickens. Meanwhile, the expression of genes related to nutrient transport and absorption in the intestine was upregulated, which reflected the enhanced digestion and absorption of nutrients in chickens supplemented with L. chiayiensis. Moreover, supplementation of L. chiayiensis down-regulated genes involved in inflammation-related, mainly involved in NF-κB signaling pathway and MHC-II mediated antigen presentation process. Cumulatively, these findings highlight that host-microbiota crosstalk enhances the host growth phenotype in two ways: by enhancing bile acid metabolism and digestive enzyme activity, and reducing the occurrence of intestinal inflammation to promote nutrient absorption and maintain intestinal health. This provides a basis for the application of LAB as an alternative to antibiotics in animal husbandry.

Autophagy-mediated expression clusters are involved in immunity regulation of coronary artery disease

BACKGROUND

The association between autophagy and immunity, including infiltrating immunocytes, immune reaction gene-sets, and HLAs (human leukocyte antigen) gene, remains unclear. The present study aimed to provide a valid diagnostic tool for coronary artery disease (CAD), and explore the pathological mechanisms of CAD based on the association between autophagy and immunity.

METHODS

First, the overlap between differentially expressed genes (DEGs) and autophagy-related genes (ARGs) was identified. Subsequently, machine learning was conducted to screen risk genes closely related to CAD. Diverse autophagy phenotype-related clusters were identified using unsupervised clustering. The connections between different clusters and immune characteristics were evaluated as well.

RESULTS

The present study identified 27 differentially expressed autophagy-related genes (DEAGRs) in CAD samples compared with healthy conrtrols. A classifier constructing by 9 DEARGs was regarded as an effective diagnostic tool for CAD. Furthermore, three distinct autophagy phenotype - related clusters were identified, each cluster exhibited different immune characteristics. Finally, the gene ontology (GO) analysis of 901 autophagy phenotype-related genes showed that immune response, protein phosphorylation, and innate immune response were remarkable enrichment components.

CONCLUSIONS

This study identified an effective classifier constituted by 9-DEARGs that has good diagnostic performance for CAD, and revealed that autophagy and the immunity may be common critical factors in the occurrence and development of CAD.