Intestinal Immune Parameters Research Articles

Effects of dietary organic acids and nature identical compounds on growth, immune parameters and gut microbiota of European sea bass

A 71-day study was conducted to explore the effect of increasing dietary levels (0, 250, 500, 1000 mg kg feed−1; D0, D250, D500 and D1000, respectively) of a blend of microencapsulated organic acids (OA, specifically citric and sorbic acid) and nature identical compounds (NIC, specifically thymol and vanillin), on growth, intestinal immune parameters and gut microbiota (GM) of European sea bass juveniles reared under normal and subsequently suboptimal environmental conditions (high temperature, 30.0 ± 0.4 °C and low oxygen, 4.6 ± 0.6 mg L−1). OA and NIC did not promote growth, feed utilisation and feed intake at the inclusion tested but induced a significantly upregulation of IL-8, IL-10 and TGFβ. GM analyzed by next-generation sequencing showed that OA and NIC were able to exert prebiotic properties stimulating the development of beneficial bacteria taxa such as Lactobacillus, Leuconostoc, and Bacillus sp. Picrust analyses displayed a significant potential functional reconfiguration of GM promoting a decrease in inflammation-promoting and homeostatic functions at increasing OA and NIC administration. For the first time on this species the exposure to suboptimal rearing conditions was able to modify GM structure reducing LAB and increasing Proteobacteria, findings which were consistent with the inflammatory process observed at mRNA level.

Erucic acid impairs intestinal immune function of on-growing grass carp (Ctenopharyngodon idella)

Erucic acid (EA) mainly occurs in rapeseed meal as an anti-nutritional factor which can deteriorate animal growth performance. To our knowledge, the deteriorated animal growth performance is closely correlated with the impaired intestinal immune function. Thus, a 60-day feeding trial was carried out to explore the relationship of EA and the intestinal immune function of on-growing grass carp (Ctenopharyngodon idella). Fish (129.17 ± 0.19 g) were distributed into 18 cages (length, width and height all equal to 1.4 m) at a stocking density of 15 individuals/m3 and received 6 diets 4 times a day to apparent satiety for 60 days. The basal diet, to which different levels of EA were added to obtain 0.00 (control), 0.29, 0.60, 0.88, 1.21 and 1.50% EA, contained 28.73% crude protein and 6.43% crude lipid. At the end of the feeding trial, 24 fish of similar body weight from each group were used in a challenged test with Aeromonas hydrophila for 6 days and then collected to evaluate the effect of EA on morbidity of enteritis, intestinal immune parameters and intestinal inflammatory parameters. In fish intestine, our study found that EA: (1) reduced the activities of lysozyme (LZ) and acid phosphatase (ACP) and the contents of complement 3 (C3), C4 and immunoglobulin M (IgM); (2) decreased the transcript levels of liver-expressed antimicrobial peptide (LEAP)-2A, LEAP-2B, hepcidin, β-defensin-1 and mucin2; (3) aggravated inflammatory response in relation to the increased transcript levels of pro-inflammatory cytokines involved in the activation of [IκB kinase β, γ (IKKβ, γ)/inhibitor of κBα (IκBα)/nuclear factor (NF)-κBp65 and c-Rel] signalling pathway and to the decreased transcript levels of anti-inflammatory cytokines involved in the suppression of [target of rapamycin (TOR)/ribosomal protein S6 kinases 1 (S6K1) and eIF4E-binding proteins (4E-BP)] signalling pathway. EA did not alter the transcript levels of interleukin (IL)-12p35, NF-κB p52 and IKKα in the intestine of on-growing grass carp. Finally, based on a straight broken-line model and using enteritis morbidity and the activities of LZ in proximal intestine (PI), mid intestine (MI) and distal intestine (DI) as response criterions, the maximum tolerance levels of EA for on-growing grass carp (129.17–471.18 g) were evaluated to be 0.53%, 0.36%, 0.44% and 0.45% diet, respectively.

Effects of Glutamine Supplementation on Broiler Performance and Intestinal Immune Parameters During an Experimental Coccidiosis Infection

SUMMARY The objective of this study was to evaluate the effects of glutamine supplementation on performance and intestinal immune parameters of broilers during an experimental coccidiosis infection. There were 3 glutamine supplementation levels in this study: 0, 0.5, and 1.0%. At 14 d of age, each bird was given an oral gavage of 20X dose of Coccivac B52 suspended in distilled water. IFN-γ mRNA levels were downregulated 11.8- and 2.0-fold in the jejunum and 8.1- and 7.9-fold in the cecal tonsils of birds supplemented with 0.5 and 1.0% glutamine at 21 d, respectively, compared to that in the birds fed 0% supplemental glutamine (P = 0.06 and P = 0.01, respectively). At 21 d of age, IL-10 mRNA levels were downregulated in the jejunum of the birds supplemented with 0.5 and 1.0% having a 25.3- and a 1.5-fold lower level, respectively (P 0.05) were observed on any performance parameter or T-cell population percentages. This study shows that glutamine supplementation upregulated tight junction protein gene expression, improved intestinal morphology, and downregulated pro- and anti-inflammatory cytokine gene expression. In conclusion, these results indicate that dietary glutamine supplementation can improve intestinal health in birds challenged with an experimental coccidiosis infection.

Corn gluten meal induces enteritis and decreases intestinal immunity and antioxidant capacity in turbot (Scophthalmus maximus) at high supplementation levels.

Corn gluten meal (CGM) is an important alternative protein source in aquafeed production. However, in turbot (Scophthalmus maximus), CGM could not be effectively utilized because of its low digestibility, the reason for which is still unclear. The purpose of the present study was to investigate and elucidate the cause for the poor utilization of CGM by turbot from the view of gut health. An 8-week feeding trial was conducted with turbot individuals (initial body weight 11.4 ± 0.2 g), which were fed with one of four isonitrogenous and isolipidic diets formulated to include 0%, 21.2%, 31.8%, and 42.6% CGM to progressively replace 0%, 33%, 50%, and 67% fish meal (FM) protein in a FM-based diet, respectively. The results showed that CGM caused dose-dependent decreases in (1) growth performance, nutrient digestibility, and feed utilization; (2) activities of brush-border membrane enzymes; (3) intestinal antioxidant indices of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activities, and reduced glutathione level; (4) intestinal immune parameters of acid phosphatase activity, complement 3, complement 4, and IgM concentrations. Dose-dependent increases in the severity of the inflammation, with concomitant alterations on microvilli structure and increasing expression of inflammatory cytokine genes of Il-1β, Il-8, and Tnf-α were observed but without a change in the intracellular junctions and the epithelial permeability established by the plasma diamine oxidase activity and D-lactate level examinations. In conclusion, the present work proved that CGM negatively affected the gut health of turbot by inducing enteritis and by decreasing intestinal immunity and antioxidant capacity, which could be one of the reasons for the reduced utilization of CGM by turbot.

Effects of Lactobacillus delbrueckii on immune response, disease resistance against Aeromonas hydrophila, antioxidant capability and growth performance of Cyprinus carpio Huanghe var

The aim of the present study was to investigate effects of dietary Lactobacillus delbrueckii (L. delbrueckii) on immune response, disease resistance against Aeromonas hydrophila (A. hydrophila), antioxidant capability and growth performance of Cyprinus carpio Huanghe var. 450 fish (mean weight of 1.05 ± 0.03 g) were randomly distributed into five groups that fed diets containing different levels of L. delbrueckii (0, 1 × 105, 1 × 106, 1 × 107 and 1 × 108 CFU g−1) for 8 weeks. The results showed that intestinal immune parameters such as lysozyme, acid phosphatase, and myeloperoxidase activities, immunoglobulin M content, and the survival rate were improved in fish fed with 1 × 106 and 1 × 107 CFU g−1L. delbrueckii. In addition, 1 × 107 CFU g−1L. delbrueckii supplementation down-regulated mRNA levels of TNF-α, IL-8, IL-1β and NF-κBp65, and up-regulated IL-10 and TGF-β mRNA levels in the intestine. The survival rate was significantly (P < 0.05) higher (68.33%) in fish fed 1 × 106 CFU g−1L. delbrueckii than the control diet-fed group (40%) after challenge by A. hydrophila. Fish fed with diet containing 1 × 106 CFU g−1L. delbrueckii showed higher antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and total antioxidant capacity (T-AOC) and lower MDA concentrations than those of the control group (P < 0.05). The relative gene expression (SOD, CAT, GPX) showed the same trend with their activities. In addition, the growth performance was significantly improved in fish fed with the diet containing 1 × 106 and 1 × 107 CFU g−1L. delbrueckii (P < 0.05). These results demonstrated that dietary optimal levels of L. delbrueckii enhanced immunity, disease resistance against A. hydrophila antioxidant capability and growth performance in Cyprinus carpio Huanghe var.

Effect of dietary inulin supplements on growth performance and intestinal immunological parameters of broiler chickens

The objective of this study was to assess the effects of dietary inulin supplementation on growth performance and intestinal immune parameters of broilers. A total of 280 one-day-old Cobb 500 male broilers were randomly allocated into four groups of seven replicate pens and given a maize-soybean basal diet supplemented with 0, 5, 10 and 15g/kg of inulin during the 42 days of the experiment. Feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR) were determined from d 1 to 21 (starter), and from d 22 to 42 (grower). Intestinal T lymphocyte subpopulations, the production of immunoglobulin A (IgA) and cytokines as well as mucin mRNA expression were measured at 21d and 42d. Feed intake was increased quadratically (P=0.001) as the dietary inulin level increasing during starter period only. However BWG and FCR of broilers were not affected by inulin supplementation in either period. At d 21 and as the dietary inulin concentration increasing, proportion of T CD4+ T lymphocyte and CD4+/CD8+ ratio in ileum tissue tended (P=0.05–0.087) to be linearly increased, IgA concentration in cecal content and mucin mRNA expression in jejunum tissue were linearly increased (P=0.006–0.01), whereas concentrations of interleuk-6 and interferon-γ in ileum tissue quadratically (P<0.05) decreased. The effects of dietary inulin on these intestinal immunological parameters were minimal at the 42-d age of broilers. These results indicated that dietary inulin at the levels of 5–10g/kg may have the beneficial effects on enhancing intestinal immune function of broiler chicken at younger age when the intestinal function is not fully developed.

The Probiotic Mixture VSL#3 Has Differential Effects on Intestinal Immune Parameters in Healthy Female BALB/c and C57BL/6 Mice1–3

Background: Probiotic bacteria may render mice resistant to the development of various inflammatory and infectious diseases.Objective: This study aimed to identify mechanisms by which probiotic bacteria may influence intestinal immune homeostasis in noninflammatory conditions.Methods: The effect of VSL#3, a mixture of 8 probiotic bacteria, on intestinal gene expression was studied in healthy female BALB/c and C57BL/6 mice after prolonged oral treatment (28 d, triweekly) with 3 × 108 colony-forming units of VSL#3. In a separate experiment in BALB/c mice, the effects of prolonged administration of VSL#3 and of phosphate-buffered saline (PBS), followed by 1 single dose of VSL#3, on innate and adaptive immune cells were evaluated.Results: Microarray analysis of the intestines of mice treated with PBS confirmed well-established differences in the expression of immune-related genes between C57BL/6 and BALB/c mice. Prolonged administration of VSL#3 was associated with downregulation of Il13[fold change (FC) = 0.46] and Eosinophil peroxidase (Epx) (FC = 0.44) and upregulation of Il12rb1 (FC = 2.1), C-C chemokine receptor type 5 (Ccr5) (FC = 2.6), chemokine (C-X-C motif) receptor 3 (Cxcr3) (FC = 1.6), and C-X-C motif chemokine 10 (Cxcl10) (FC = 2.8) in BALB/c mice but not in C57BL/6 mice. In BALB/c mice, it was shown that 28 d of treatment with VSL#3 affected the Peyer's patches (PPs) and mesenteric lymph nodes (MLNs), which was evident from an increase in B cells (26% and 8%, respectively), a decrease in T cells (21% and 8%, respectively), and an increase in cluster of differentiation (CD) 11c+ cells (57% in PPs) compared with PBS-treated mice. This treatment was also associated with increased frequencies of T helper 17 (13%) and regulatory T cells (11%) in the MLNs. Treatment with PBS followed by 1 single dose of VSL#3, 18 h before killing, was associated with a 2-fold increase in CD103+CD11c+ dendritic cells in MLNs and PPs.Conclusion: VSL#3 treatment mediates mouse strain–specific alterations in immunologic phenotype in conditions of homeostasis, suggesting that the effects of probiotic bacteria depend on the genetic background of the host.

Probiotic Treatment Decreases the Number of CD14-Expressing Cells in Porcine Milk Which Correlates with Several Intestinal Immune Parameters in the Piglets.

Modulating the mucosal immune system of neonates by probiotic treatment of their mothers is a promising approach which can only be investigated through the use of animal models. Here, we used sows and their piglets to investigate the impact of a bacterial treatment on the sow’s milk and on the neonate piglet intestinal immune system. In previous experiments, feed supplementation of sows with the probiotic Enterococcus faecium NCIMB 10415 during pregnancy and lactation had been shown to affect intestinal microbiota and cytokine expression of the offspring during the suckling and weaning periods. We therefore investigated the composition of the milk from treated sows in comparison to samples from a control group. In treated sows, the amount of lactose increased, and the somatic cell numbers were reduced. In all milk samples, the percentage of cells expressing membranous CD14 (mCD14) was greater than the fractions of immune cells, indicating expression of mCD14 on mammary epithelial cells. However, in the milk of E. faecium-treated sows, mCD14+ cells were reduced. Furthermore, the number of CD14+ milk cells was positively correlated with the percentages of B cells and activated T cells in the ileal MLN of the piglets. This study provides evidence for the expression of mCD14 by the porcine mammary epithelium, and suggests an immunological effect of mCD14+ milk cells on the piglets’ intestinal immune system. Our study further suggests that mCD14+ mammary epithelial cell populations can be modulated by probiotic feed supplementation of the sow.

Effect of polyoxyethylene and polyoxypropylene nonionic block copolymers on performance and recruitment of immune cell subsets in weaned pigs

BackgroundBecause European-wide directives are restricting the non-clinical use of antibiotics as in-feed growth promotors in swine production, there is an intensive search for alternative strategies for control and prevention of losses among young pigs. With the growing knowledge of the porcine immune system and its endogenous modulation, it has been clearly established that exogenous immunomodulation using adjuvants and immune response modifiers (IRMs) represents an important prophylactic/therapeutic approach in the prevention/treatment of both stress- and microbial-induced disorders that accompaning weaning. However, it is essential to select a fully evaluated agent which may act either as a nonspecific IRM or synergistically as an adjuvant with vaccines. The synthetic macromolecules with a long history as adjuvant and IRM are nonionic block copolymers which consist of polyoxyethylene (POE) and polyoxypropylene (POP) molecules.MethodsThe aim of this work was to evaluate the effectiveness of POE-POP given as a single peroral dose on productivity parameters such as body weight gain, feed intake and feed conversion ratio, and systemic and intestinal immune parameters by assessing the proportions of CD45+ lymphoid cells, CD4+ and CD8+ T cells, and CD21+ B cells in the peripheral blood as well as the number of CD45RA+ naive lymphoid cells residing in the ileal mucosa in weaned pigs during a follow-up study 5 weeks after the treatment.ResultsPigs treated with POE-POP had better feed intake (+ 14.57%), higher average body mass at the end of the experiment (20.91 kg vs. 17.61 kg), and higher body weight gain in relation to Day 0 (191.63% vs. 144.58%) as well as in relation to nontreated pigs (+ 18.74%), with a lower feed conversion ratio (− 30.26%) in comparison to the control pigs. A much lower diarrhea severity score (5 vs. 54) was recorded in pigs treated with POE-POP (− 90.74%) than in the control pigs. A higher average diarrhea severity (ADS) was recorded in the control pigs (1.54 vs. 0.14), whereas the treatmant group had much a lower ADS ratio (− 90.91%) after 35 days of the experiment. The pigs that were treated with POE-POP had an increased proportion of CD45+, CD4+ and CD8+ cells at Day 21 (at p < 0.05, p < 0.05 or p < 0.01, respectively), Day 28 (at p < 0.01, respectively) and Day 35 (at p < 0.01, p < 0.05 or p < 0.01, respectively) as well as of CD21+ cells at Day 28 (p < 0.05) and Day 35 of the experiment (p < 0.01). Also, these pigs had more numerous CD45RA+ cells in interfollicular (p < 0.05) and follicular areas (p < 0.01) of the ileal Peyer’s patches than did control pigs.ConclusionThis property of POE-POP to induce recruitment of circulating and intestinal immune cell subsets in weaned pigs may allow the use of IRM-active block copolymers as adjuvants for vaccines, particularly those orally delivered and targeted to the gut-associated lymphoid tissues that are well known to promote rather tolerogenic than protective immune responses.

Effect of yeast cell product supplementation on broiler cecal microflora species and immune responses during an experimental coccidial infection

This experiment was conducted to study the effects of whole yeast (Pichia guilliermondii; CitriStim, ADM, Quincy, IL) cell product supplementation on cecal microflora population and intestinal immune parameters in broilers. In the first experiment, birds were fed 0, 0.1, or 0.2% yeast cell wall product for 42 d. Feeding yeast cell wall products decreased (P = 0.03) the proportion of Escherichia coli in the ceca by 31% compared with the control group. The group fed 0.2% yeast cell wall product had a 20% decrease (P = 0.23) in Salmonella population compared with the control group. In the second experiment, birds were fed yeast cell wall product for 21 d and challenged or not challenged with coccidial oocysts, thus resulting in a 2 (0 and 0.2% whole yeast product) × 2 (coccidial challenge and no coccidial challenge) factorial model. Supplementing whole yeast cell wall product prevented a coccidial infection-induced decrease in the Lactobacillus population (P = 0.09) at 12 d postchallenge. Supplementing yeast cell wall product prevented a coccidial infection-induced increase in the Salmonella population (P = 0.08) and E. coli (P = 0.12) at 12 d postchallenge. At 5 d (P < 0.01) and 12 d (P < 0.01) postcoccidial infection, yeast cell wall product supplementation or coccidial infection increased the regulatory T cell (Treg) percentage in the cecal tonsils, whereas yeast cell wall product supplementation in the coccidial-infected group decreased the increase in Treg percentage. At 5 d postcoccidial infection, coccidial infection increased (P = 0.01) the relative amounts of cecal interferon (IFN)γ mRNA. In addition, the yeast cell wall product supplementation in the coccidial-infected groups further increased (P = 0.15) the IFNγ mRNA. It could be concluded that yeast cell wall product supplementation decreased coccidial-infection-induced increase in E. coli and Salmonella colonization and improved IFNγ mRNA amounts after coccidial infection.