Mucosal Immune Parameters Research Articles

Effects of dietary supplementation of spray dried hog plum (Spondias pinnata (L.f.) Kurz) fruit powder on growth, digestive enzyme activity, and skin mucus immune parameters of climbing perch (Anabas testudineus (Bloch, 1972)

The effects of dietary supplementation of spray-dried hog plum (Spondias pinnata (L.f.) Kurz) fruit powder (SPP) on growth, digestive enzyme activity, and skin mucus immune parameters of climbing perch (Anabas testudineus (Bloch, 1972)) were examined. The fish (N = 330; 2.00±0.1 g) were assigned to five groups in triplicates. They were fed different SPP levels at 0, 5, 10, 15, and 20 g/kg diet for eight weeks. Flavonoids, terpenoids, phenolic compounds, tannins, steroids, glycosides, and glycosides were detected in SPP. The SPP containing diet significantly improved growth parameters (P < 0.05) without a negative effect on the survival rate (P > 0.05). Intestinosomatic and hepatosomatic indices significantly declined in the fish fed SPP added diets (P < 0.05). There were significant elevations in digestive enzyme activities, amylase, protease, lipase, trypsin, pepsin, and esterase, in the tested fish compared to the control fish (P < 0.05). Additionally, fish fed SPP containing diets showed a significant enhancement of total protein, immunoglobulin M, lysozyme, antiprotease, alkaline phosphatase, and esterase in the skin mucus compared to the control group (P < 0.05). Significantly higher levels of superoxide dismutase, catalase, and total antioxidant capacity were detected in fish fed SPP containing diets compared to the control (P < 0.05). These findings suggest that dietary SPP supplementation can effectively enhance fish growth, digestive enzyme activities, and mucosal immune parameters in the climbing perch. The suitable level of SPP observed in this present study was 13.00 – 15.88 g/kg diet.

Skin mucosal immune parameters and expression of the immune-relevant genes in Danio rerio treated by white button mushroom (Agaricus bisporus).

This study evaluates using different levels of the white button mushroom powder (WBMP) on some mucosal innate immune parameters (lysozyme, protease, esterase, alkaline phosphatase activities, and total immunoglobulin levels), and the relative expression of some principal immune-relevant genes (lysozyme, TNF-α, and IL-1β) in the zebra danio intestine. Zebrafish specimens (1.75 ± 0.25g) were divided into experimental units based on the additives to a diet including 5, 10, and 20g of WBMP per kilogram of food weight, alone or in conjunction with the antibiotic (10mg/kg BW), and the AGRIMOS (1g/kg food weight). Following the 11-day experimental duration, the skin mucus and intestine were sampled. To assess the immune gene expression, the real-time PCR detection system was conducted according to the ΔΔCt method using the IQ5 software (Bio-RAD). Results showed that all groups had a significant increase in terms of mucosal lysozyme activity compared to the control group. Examination of total immunoglobulin, protease, esterase, and ALP activity in fish under experimental treatment showed that there was no significant difference between the trial groups and the control groups. The most expression of the lysozyme gene was related to the group that was separately taken the lower concentration (5g per kg of FW) of WBMP. In conclusion, the amount of 1% mushroom powder in the diet can improve its immune function. Our recommendation is that given the positive effects that mushroom powder added on the diet alone, avoid taking antibiotics for this purpose.

Effects of Dietary Limonene Supplementation on Growth Performance and Immunological Parameters of Common Carp, Cyprinus carpio, Challenged by Aeromonas hydrophila.

This study examined the impact of dietary limonene treatment on the growth performance, immune response, and disease resistance of common carp, Cyprinus carpio. The fish were fed with either a control diet (CTL; no limonene supplementation) or four experimental diets containing 50 (50 L), 100 (100 L), 200 (200 L), and 400 (400 L) mg/kg limonene over a 70-day period, followed by Aeromonas hydrophila challenge. The 200 L treatment resulted in a significant decrease in FCR compared to the CTL treatment. The highest post-challenge mortality was associated with the CTL treatment (62.7%), while the 200 L treatment had the lowest mortality (30.7%). Before the challenge, dietary limonene significantly increased humoral and skin mucosal immune parameters compared to the CTL treatment. The highest leukocyte, lymphocyte counts, skin mucosal protease activity, and intestinal lactic acid bacteria were observed in the 200 L treatment before the challenge. The highest plasma lysozyme activity was observed in the 400 L treatment, whereas the highest skin mucosal lysozyme and peroxidase activities were observed in the 100 L and 200 L treatments before the challenge. There were no significant differences in the blood neutrophil, monocyte, and eosinophil counts, humoral alternative complement activity, skin mucosal alkaline phosphatase activity, and the intestinal total viable bacteria among the treatments before the challenge. After the challenge, the 200 L treatment exhibited the highest leukocyte, neutrophil, and monocyte count, skin mucosal immune parameters, and intestinal lactic acid bacteria, whereas the highest blood eosinophil count was observed in the 100 L, 200 L, and 400 L treatments. At this time, the lowest blood lymphocyte counts were observed in the 100 L and 200 L, but the lowest intestinal total viable bacteria were observed in the 100 L, 200 L, and 400 L treatments. Based on these findings, dietary limonene at 200 mg/kg is ideal for common carp to promote feed efficiency, innate immunity boosting, and resistance against A. hydrophila.

Dietary powder and molecular imprinted polymer nanoencapsulated sodium propionate to enhance growth performance, digestive enzymes activity, antioxidant defense, and mucosal immune response in African cichlid (Labidochromis lividus) fingerlings

Abstract This study was conducted to examine the effects of powder sodium propionate (P-SP) and SP- loaded molecular imprinted polymer (MIP) nanoparticles (MIP-SP NPs) on the growth, skin mucosal immune parameters, and digestive and liver enzymes activities of African cichlid (Labidochromis lividus) fingerlings. Fish with an average weight of 500±2 mg were stocked into 12 experimental units and fed on experimental diets prepared by supplementing the basal diet (control) with MIP NPs, P-SP (5 g SP kg−1 of dry diet), and MIP-SP NPs for 8 weeks. The findings demonstrated that growth indices improved in the MIP-SP NPs followed by the P-SP dietary group compared to the control groups (P<0.05). The activity of digestive enzymes of lipase, trypsin, protease, and alkaline phosphatase was higher in the fish fed SP-supplemented diets than in the controls (P<0.05). The protease and lipase activities in the MIP-SP NPs dietary group increased by 29.33% and 48.81% compared to the control, respectively (P<0.05). In addition, the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of liver tissue decreased in the SP dietary groups, while the catalase (CAT ), superoxide dismutase (SOD), and alkaline phosphatase (ALP) levels increased compared to the control groups (P<0.05). The highest SOD and ALP levels were observed in the fish fed on the MIP-SP NPs-supplemented diet (P<0.05). Furthermore, the skin mucosal immune indices, including alternative hemolytic complement activity (ACH50), lysozyme, and total immunoglobulin (Ig) levels increased in the MIP-SP NPs and P-SP dietary groups compared to the controls (P<0.05). The findings indicated that sodium propionate encapsulated in molecularly imprinted polymer nanoparticles could enhance the efficiency of dietary SP in African cichlid fish.

Post-acute sequelae of COVID-19 is characterized by diminished peripheral CD8+β7 integrin+ T cells and anti-SARS-CoV-2 IgA response

Several millions of individuals are estimated to develop post-acute sequelae SARS-CoV-2 condition (PASC) that persists for months after infection. Here we evaluate the immune response in convalescent individuals with PASC compared to convalescent asymptomatic and uninfected participants, six months following their COVID-19 diagnosis. Both convalescent asymptomatic and PASC cases are characterised by higher CD8+ T cell percentages, however, the proportion of blood CD8+ T cells expressing the mucosal homing receptor β7 is low in PASC patients. CD8 T cells show increased expression of PD-1, perforin and granzyme B in PASC, and the plasma levels of type I and type III (mucosal) interferons are elevated. The humoral response is characterized by higher levels of IgA against the N and S viral proteins, particularly in those individuals who had severe acute disease. Our results also show that consistently elevated levels of IL-6, IL-8/CXCL8 and IP-10/CXCL10 during acute disease increase the risk to develop PASC. In summary, our study indicates that PASC is defined by persisting immunological dysfunction as late as six months following SARS-CoV-2 infection, including alterations in mucosal immune parameters, redistribution of mucosal CD8+β7Integrin+ T cells and IgA, indicative of potential viral persistence and mucosal involvement in the etiopathology of PASC.

Shaping approaches to standardization of oropharynx mucous membrane assessment of immunological parameters

Validation of biological sampling techniques to study the parameters of local mucosal immunity in oropharynx acute inflammatory diseases. 30 people with acute catarrhal pharyngitis with intoxication syndrome were examined. The sampling was carried out in 7 different ways. 1. Collect saliva samples using the passive drool collection method. 2. Collect saliva, using cotton swabs placed into the mouth for 3 minutes. 3. Cotton swabs wrapped around a metal probe was placed on palatine tonsils and lateral walls of the oropharynx. 4. Instead of a cotton swab, a disc of laboratory filter paper with a diameter of 0.7 cm was used. 5. Scrape by the mucous membrane of the palatine tonsils and lateral walls of the oropharynx were made with a cytobrush. 6. Using a cytobrush, scrapings were made from the mucous membrane of only the posterior pharyngeal wall, excluding the region of the palatine tonsils. 7. Using a cytobrush to make scrapings from the only palatine tonsils mucous membrane. RT-PCR was used to determine IL-1β mRNA. Minimal IL-1β mRNA values were detected in saliva collected by passive flow (0.095 [0; 3.45] units) and on a cotton swab (0.21 [0.1; 3.82] units). IL-1β mRNA in the material collected by methods No. 3 and No. 4 on a cotton swab and a paper disk did not differ significantly from each other. Its level was higher than in saliva and lower than in scrapings. The maximum result was revealed with method No. 5 when simultaneously taking scrapings from the palatine tonsils and posterior pharyngeal wall mucous membrane (4.76 [0.92; 8.13] units). The expression of IL-1β mRNA in the material obtained by methods No. 6 and No. 7 did not differ significantly from each other. Separated scrapings collecting from the palatine tonsils or posterior pharyngeal wall mucous membrane will allow assessing the inflammatory response autonomously in the lymphoid tissue and separately on the mucosa of the posterior pharyngeal wall. The mucosal scraping technique was the most effective for assessing cytokines in the oropharyngeal mucosal membrane.

Effects of Bougainvillea glabra leaf on growth, skin mucosal immune responses, and disease resistance in common carp Cyprinus carpio

This study evaluated the effects of Bougainvillea glabra (BG) leaf as a feed supplement on growth, skin mucosal immune parameters, serum oxidative stress, expression of immune-related genes, and susceptibility to pathogen infection in carp Cyprinus carpio. Diets containing four different BG concentrations (g kg−1), i.e., 0 g (basal diet), 20 g (BG20), 30 g (BG30), 40 g (BG40), and 50 g (BG50), were fed to the carp (average weight: 14.03 ± 0.81 g) for 8 weeks. Skin mucosal immunological and serum antioxidant parameters were examined 8 weeks post-feeding. Growth performance was significantly higher in BG40. Among the examined skin mucosal immune parameters, lysozyme (33.79 ± 0.98 U mL−1), protein (6.88 ± 0.37 mg mL−1), immunoglobulin (IgM; 5.34 ± 0.37 unit-mg mL−1), and protease activity (3.18 ± 0.36%) were significantly higher in BG40 than in the control; whereas, there was no significant effect on the alkaline phosphatase level. Among serum immune activity, activities of lysozyme, the alternative complement pathway, and IgM were significantly higher in BG40. Phagocytic, and superoxide dismutase (SOD) activities were higher (P < 0.05) in BG30–BG50. Serum ALT, AST, and MDA levels were lower in BG40 than in the control (P < 0.05). Intestinal enzymatic activities were enhanced in BG40 and BG50 (P < 0.05), except for lipase in BG50. Gene expression analysis revealed that the mRNA expressions of antioxidant genes (SOD, GPx, and Nrf2), an anti-inflammatory gene (IL-10), and IκBα were significantly upregulated in BG40. Conversely, the pro-inflammatory gene IL-1β and the signaling molecule NF-κB p65 were downregulated in BG40 and BG50, respectively. BG supplementation had no significant effect on TNF-α, TLR22, or HSP70 mRNA expressions. Moreover, fish in BG40 exhibited the highest relative post-challenge survival (67.74%) against Aeromonas hydrophila infection. These results suggested that dietary supplementation with BG leaves at 40 g/kg can significantly improve the growth performance, immune responses, and disease resistance of C. carpio. BG leaves are a promising food additive for carp in aquaculture.

Effect of Dietary Administration of Green Macroalgae (Ulva intestinalis) on Mucosal and Systemic Immune Parameters, Antioxidant Defence, and Related Gene Expression in Zebrafish (Danio rerio).

This study investigated the effects of adding green macroalgae gutweed (Ulva intestinalis) powder to zebrafish (Danio rerio) feed at different levels on innate immune responses, antioxidant defence, and gene expression. A total of 600 zebrafish (0.3 ± 0.08 g) were randomly allocated to 12 aquariums in four treatments with three replicates (50 fish per aquarium). Zebrafish were fed with different levels of U. intestinalis powder 0, 0.25, 0.5, and 1% for eight weeks. Whole-body extract (WBE) immune parameters including total protein level, globulin level, and lysozyme activity were evaluated and revealed statistically significant increased in all U. intestinalis supplemented groups compared to the control (P < 0.05). However, mucus immune parameters (total protein, globulin, and lysozyme) were statistically different in only 1% gutweed supplemented groups from other groups. While glutathione peroxidase (GPx) and superoxide dismutase (SOD) increased with the addition of gutweed (P < 0.05), catalase (CAT) did not change (P > 0.05). The study results showed that dietary gutweed remarkably upregulated immune-related genes such as lysozyme (Lyz) and Interleukin 1 beta (IL-1β). Antioxidant-related genes (SOD and CAT) and growth-related genes, including growth hormone (GH) and insulin-like growth factor-I (IGF-1), were remarkably upregulated with gutweed treatment (P < 0.05). In conclusion, dietary U. intestinalis showed beneficial effects on immunity, and same effects were observed in case of antioxidant and growth related genes expression in zebrafish.

Evaluation of Soil-Derived Streptomyces chartreusis KU324443 Effects as Probiotic on Growth Performance, Antioxidant Enzyme Activity, Mucosal and Serum Immune Parameters, and Related Gene Expression in Common Carp (Cyprinus carpio) Fingerlings

The present trial investigates the effects of soil-derived Streptomyces chartreusis KU324443 as a probiotic on growth performance, mucosal and serum immune parameters, and immune and antioxidant-associated gene expression in common carp (Cyprinus carpio). In a two-month experiment, carps were fed with varying levels of S. chartreusis KU324443 (0 (control), 105 (S1), 106 (S2), and 107 (S3) CFU/g). Then, performance, skin mucus, and serum immune parameters besides immune and antioxidant-related gene expression (IL1 and Lyz, CAT and SOD) were measured. Fish fed S. chartreusis-supplemented diet showed a significant increase in growth performance parameters ( P &lt; 0.05 ) regardless of inclusion levels. Including different doses of S. chartreusis significantly increased serum total Ig and lysozyme activity compared to those fed the control diet ( P &lt; 0.05 ). While no significant difference was noticed in the case of skin mucus total Ig ( P &gt; 0.05 ), lysozyme activity showed a significant increase in S. chartreusis-treated carps ( P &lt; 0.05 ). No significant differences ( P &gt; 0.05 ) were noticed in the case of serum antioxidant enzyme activity (CAT, SOD, and GPx) of S. chartreusis-fed carps and control. However, fish fed the control diet recorded the highest SOD and GPx enzyme activity in skin mucus of common carp, while no significant differences were noticed in the case of mucus CAT enzyme activity in common carp ( P &gt; 0.05 ). Gene expression studies revealed noticeable alterations between treated fish and control. Fish in S3 treatment had significantly higher CAT, SOD, Lyz, and IL1 expression ( P &lt; 0.05 ). These results confirmed the beneficial effects of a soil-derived probiotic (S. chartreusis) on the performance and health of common carp.

Impact of dandelion polysaccharides on growth and immunity response in common carp Cyprinus carpio

Natural products have gained considerable attention for improving fish growth performance and immunity to enhance disease resistance. This study evaluated the effect of dandelion polysaccharides (DP) on skin mucosal immune parameters, immune-related gene expression, and susceptibility to pathogen challenge in the Common carp Cyprinus carpio. Diets containing four different concentrations of DP (g Kg−1):0 g [basal diet], 0.5 g [D1], 1.5 g [D2], 2.5 g [D3], and 4.0 g [D4] were fed to the carp (average weight: 13.92 ± 0.83 g) for eight weeks. Growth parameters were analyzed four and eight weeks after feeding. Immunological, hematological, and antioxidant parameters were examined eight weeks post-feeding. Growth performance was significantly higher on D3, with a final weight gain of 71.48 ± 1.57 g and a specific growth rate of 3.06 ± 0.12. Among hematological parameters examined, erythrocyte, hematocrit, and mean corpuscular volume (MCV) levels were significantly higher in D3. Skin mucosal immune parameters, such as lysozyme (31.04 ± 1.02 Unit mL−1), alkaline phosphatase (122.6 ± 3.8 IU L-1), and protein level (10.6 ± 0.74 mg mL−1) were significantly higher in D3, while peroxidase activity was higher in D4. Furthermore, SOD activity was higher in D2–D3, whereas catalase activity was higher in D2–D4 (P < 0.05) than in the control. Malondialdehyde level decreased significantly in D3 (5.43 ± 0.36 nmol mL−1); whereas, serum ALT and AST levels were significantly lower on D2-D4. Intestinal tight-junction-related genes ZO-1 and Claudin 7 were significantly higher in the DP-fed groups; however, DP had no significant effect on claudin 3. Occludin expression was higher (p < 0.05) on D3 only. Pro-inflammatory cytokines (IL-1β and TNF-α) and IFN–γ strongly upregulated in the head kidney at D3. Conversely, the expression of the anti-inflammatory cytokine interleukin-10, HSP70, and TOR were considerably downregulated in D3. Fish from D3 exhibited markedly higher relative post-challenge survival (66.67%) against Aeromonas hydrophila challenge. The results of the present study suggest that dietary supplements of DP at 2.5 g kg−1 can significantly improve the growth performance, skin mucosal, and serum antioxidant parameters, and strengthen the immunity of C. carpio. Therefore, DP is a promising food additive for carp aquaculture.

Seasonal variations in the skin epidermal structure and mucosal immune parameters of rainbow trout skin (Oncorhynchus mykiss) at different stages of farming

The aim of this study was to investigate the seasonal changes in the epidermal structure and the innate immunity parameters of skin mucus in rainbow trout. The skin epidermis and mucus samples were collected over three consecutive seasons including winter, spring and late summer from three different weight groups i.e., 2–20 g (W1), 100–200 g (W2) and 400–600 g (W3) fish. The skin mucosal immunity analysis of rainbow trout showed that the haemagglutination activity increased significantly with increasing fish size from W1 to W3 in all three seasons, while no significant seasonal changes occurred in haemagglutination activity. Moreover, the bactericidal activity against fish pathogens increased significantly with increasing water bacterial load in late summer. The SDS-PAGE analysis of mucus showed a high amount of low molecular weight proteins (<35 kDa) in the late summer that was correlated with the increase in bactericidal activity. Histological analysis of the epidermis structure of rainbow trout skin showed that the density and size of goblet cells and consequently the mucus secretion significantly increased in W3 group in all seasons. In all three weight groups of fish, the density of goblet cells significantly increased from winter to spring and late summer along with increasing water temperature. Moreover, the goblet cell density showed a significant positive relationship with the soluble protein concentration and haemagglutination activity (p < 0.01). The results of this study demonstrated the more active immune role of the skin epidermal cells and mucus in rainbow trout during summer to protect fish against the pathogenic microorganisms. Given its potent bactericidal properties and the lack of haemolytic activity, the rainbow trout mucus might be used as a safe and inexpensive source for developing antimicrobial agents to prevent and treat some bacterial diseases in human and fish.

The effects of dietary fermented wheat bran polysaccharides on mucosal and serum immune parameters, hepatopancreas antioxidant indicators, and immune-related gene expression of common carp (Cyprinus carpio) juveniles

The effects of dietary fermented wheat bran polysaccharides on mucosal and serum immune parameters, hepatopancreas antioxidant indicators, and immune-related gene expression of common carp (Cyprinus carpio) juveniles

The association between parameters of oral mucosal immunity and 25-hydroxyvitamin D in patients with rampant caries

Aim. To determine the saliva level of immunoregulatory proteins in patients with rampant caries and 25-hydroxyvitamin D (25(OH)D) deficiency and evaluate the association of their concentration with 25(OH)D plasma level.Materials and methods. The study was performed in two groups. The experimental group included 15 patients aged 20–22 years with rampant caries and the 25(OH)D plasma level of &lt; 20 ng / ml. The control group encompassed 15 healthy age-matched volunteers with the 25(OH)D plasma level of 20–100 ng / ml. The concentrations of B7.2 (CD86), free active TGF-β1, CTLA-4, PD-1, Tim-3, LAG-3, IGFBP-4, and ICAM-1 were assessed using flow cytometry. The levels of LL-37 and secretory immunoglobulin A (sIgA) were measured using ELISA. The Spearman’s rank correlation coefficient was used to reveal a correlation between the indicated proteins and the 25(OH)D plasma level.Results. A decrease in B7.2 (CD86), PD-1, Tim-3, sIgA, and LL-37 and elevation of IGFBP-4 and ICAM-1 saliva levels were detected in patients with rampant caries and 25-hydroxyvitamin D deficiency. A positive Spearman’s rank correlation coefficient was revealed between plasma 25(OH)D and saliva levels of free active TGF-β1, CTLA4, B7.2 (CD86), LL-37, and sIgA. A negative correlation was revealed between 25(OH)Dand ICAM-1.Conclusion. 25(OH)D deficiency in patients with rampant caries is associated with decreased levels of B7.2 (CD86), PD-1, Tim-3, sIgA, and LL-37 and elevated levels of IGFBP-4 and ICAM-1 in the saliva.

Efficiency of elimination-irrigation therapy in children with allergic rhinitis and recurrent respiratory

Introduction. Despite new diagnostic methods contributing to an understanding of the etiopathogenesis of acute respiratory tract diseases and a variety of drugs for effective therapy, respiratory tract diseases continue to stand first in the overall morbidity profile in both children and adults. Frequently ill children are most susceptible to diseases, especially at the age of 3 to 6 years old, which accounts for up to 75% of all acute respiratory infection cases and shows no positive response to the medical-preventive activities. The article discusses the relationship between allergic rhinitis and recurrent respiratory diseases.Materials and methods. The possibility and effectiveness of complex treatment of allergic rhinitis in 65 frequently ill children aged 3 to 12 years are considered. The main group consisted of 35 children who were included in the traditional anti-allergic therapy with an isotonic solution of sea salt in an age-related dose for 10 days. The comparison group consisted of 30 children who received only traditional anti-allergic therapy, which was comparable in the compared groups. Patients underwent in-depth clinical and specific allergological examinations, as well as assessment of atopic response parameters of mucosal immunity, including determination of eosinophil levels, side, and Il-4 concentrations in nasal secretions.Results. Thus, the 12-month follow-up control over children with AR showed that the annual frequency of ARIs in the treatment group decreased by 1.4 times and, when averaged, was 5.2 cases, while in the comparison group it was 7.3 cases p &lt; 0.05.Conclusions. In children with recurrent respiratory diseases, suffering from allergic rhinitis, the complex anti-allergic therapy, with the inclusion of elimination and irrigation therapy with a preparation based on isotonic sea salt solution, led to a decrease activity of markers of allergic inflammation in the nasal mucosa, which is confirmed by a decrease in the level of eosinophils, secretory IgE and IL-4 in nasal secretions against the background of a decrease in the frequency of acute respiratory diseases during follow-up for a year.

Selenium nanoparticle and selenomethionine as feed additives: effects on growth performance, hepatic enzymes' activity, mucosal immune parameters, liver histology, and appetite-related gene transcript in goldfish (Carassius auratus).

The aim of this study was to assess the effects of different dietary selenium sources, selenium nanoparticle (nSe), and selenomethionine (SeMet) as feed additives on growth performance, hepatic enzymes' activity, biochemical, mucosal immune parameters, liver histology, and appetite-related gene transcript in goldfish (Carassius auratus). At first, goldfish juveniles (n=480; mean 4.54 g) were fed dietary selenium nanoparticle at 0, 0.3, 0.6, and 0.9 mg nSe/kg diet and SeMet at 0, 0.3, 0.6, and 0.9 mg Se/kg for 9 weeks. Growth performance was evaluated using standard procedures. Blood, skin mucus, and tissue samples (liver and intestine) were collected for biochemical, mucosal immune response, histology, and ghrelin and insulin-like growth factor-I (IGF-I) gene expression. The results showed that fish fed diets fortified with 0.6 mg nSe/kg and 0.6 mg Se/kg had a significant higher weight gain, specific growth rates (SGR), and lower feed conversion ratios (FCR) than fish fed basal diets (p<0.05). Furthermore, dietary nSe and SeMet enhanced blood biochemical profiles especially alkaline phosphatase (ALP) (p < 0.05) and mucosal immunity than the control group in goldfish. Moreover, the liver histological investigation showed that fish fed 0.9 mg of SeMet and nSe kg-1 diets had higher liver lesion scores such as karyolysis, lipidosis, and hyperemia while fish fed 0, 0.3, and 0.6 mg of SeMet and nSe kg-1 diets had small liver changes at 9 weeks. The study further established that inclusion of nSe and SeMet in the diet of goldfish greatly promoted ghrelin and IGF-1genes expressions (p <0.05). Overall, dietary nSe performs better than SeMet and basal diets. The results evoked that nSe and SeMet stimulate the growth, biochemical, and mucosal immunity in goldfish at 0.6 mg/kg.

Changes in rainbow trout (Oncorhynchus mykiss) growth and mucosal immune parameters after dietary administration of grape (Vitis vinifera) seed extract.

The effect of dietary grape (Vitis vinifera) seed extract (GSE) on growth performance and mucosal immune parameters in rainbow trout (Oncorhynchus mykiss) fry was studied. Fish (1.3 g mean weight) were randomly distributed in nine tanks (15 fish per tank) and fed diets containing GSE at 0 (control), 100, and 200 mg kg-1for 60 days. The results showed that growth parameters were enhanced in both treatment groups compared to the control group. Histological examination of fish skin showed higher epidermis thickness, goblet cell density, and volume density in the GSE groups compared to the values of the control group. Furthermore, the villus height, goblet cell density, and intraepithelial lymphocytes were increased in the fish intestine in those fish fed GSE, with respect to control fish. Feeding fish with low dose of GSE (100 mg kg-1) up-regulated the expression of some immune-relevant genes, including complement component 3 (C3), lysozyme (Lys), omDB-3, interferon gamma (IFN-γ), and tumor necrosis factor-α (TNF-α) in different mucosal tissues. However, feeding fish the high dose of GSE (200 mg kg-1) mostly enhanced expression of these genes in the skin. Besides, skin mucus of fish fed GSE showed bactericidal activity against Yersinia ruckeri. It was concluded that GSE, especially at 100 mg kg-1, modulates the growth performance and mucosal immunity of rainbow trout.

Comparison of Circulating Markers and Mucosal Immune Parameters from Skin and Distal Intestine of Atlantic Salmon in Two Models of Acute Stress.

Ensuring salmon health and welfare is crucial to maximize production in recirculation aquaculture systems. Healthy and robust mucosal surfaces of the skin and intestine are essential to achieve this goal because they are the first immunological defenses and are constantly exposed to multistressor conditions, such as infectious diseases, suboptimal nutrition, and environmental and handling stress. In this work, Atlantic salmon, split from a single cohort, were subjected to acute hypoxia stress or 15-min crowding stress and observed over a 24-h recovery period. Samples were collected from fish at 0, 1, 3, 6, 12 and 24 h post-stress to analyze plasma-circulating markers of endocrine function (cortisol), oxidative stress (glutathione peroxidase) and immune function (interleukin 10 (IL-10), annexin A1). In addition, mucosal barrier function parameters were measured in the skin mucus (Muc-like protein and lysozyme) and distal intestine (simple folds, goblet cell size and goblet cell area). The results showed that both acute stress models induced increases of circulating cortisol in plasma (1 h post-stress), which then returned to baseline values (initial control) at 24 h post-stress. Moreover, the hypoxia stress was mostly related to increased oxidative stress and IL-10 production, whereas the crowding stress was associated with a higher production of Muc-like protein and lysozyme in the skin mucus. Interestingly, in the distal intestine, smaller goblet cells were detected immediately and one hour after post-hypoxia stress, which could be related to rapid release of the cellular content to protect this organ. Finally, the correlation of different markers in the hypoxic stress model showed that the circulating levels of cortisol and IL-10 were directly proportional, while the availability of Muc-like proteins was inversely proportional to the size of the goblet cells. On the other hand, in the crowding stress model, a proportional relationship was established between plasma cortisol levels and skin mucus lysozyme. Our results suggest key differences in energy partitioning between the two acute stress models and support the need for further investigation into the interplay of multistressor conditions and strategies to modulate immunological aspects of mucosal surfaces.

Influence of Lacto-Immuno-Vital on growth performance and gene expression of IgA, MUC-2, and growth factor IGF-2 in the jejunum of broiler chickens

The effects of Lacto-Immuno-Vital synbiotic preparation on gene expression of IgA, MUC-2, and growth factor IGF-2 in the jejunum and on BW gain in broiler chickens were studied. A flock of 64,400 1-day-old Hybrid ROSS 308 chickens was inducted in the 42-day experiment. The chickens were divided into 2 equally size groups in separate halls. The chickens in the experimental (E) group received 500 g of Lacto-Immuno-Vital in 1,000 L of drinking water. The preparation was administered daily from the first day (day 1) to day 7 of the experiment. From day 7 to day 22, it was given in pulsed manner (every third day) at a dose of 300 g in 1,000 L of drinking water. The broiler chickens in the E group gained more weight (P < 0.001) compared with control from day 10 to day 42. Death of animals during feeding period was 1,078 chickens in the E group compared with 1,115 dead chickens in the control group. Feed conversion ratio was 1.61 kg of supplemented diet/kg of BW in the E group compare with 1.67 kg of nonsupplemented diet/kg of BW in control. The relative expression of IgA gene in the jejunum was upregulated on day 22 in the E group compared with control (P < 0.05), whereas relative expression of MUC-2 gene was upregulated in the E group compared with control on day 8 and day 22 (P < 0.05; P < 0.001). Similarly, relative expression of IGF-2 gene was upregulated in the E group compared with control on both samplings (P < 0.01). The composition of Lacto-Immuno-Vital synbiotic preparation showed beneficial effects on growth performance, feed conversion ratio, morbidity, mortality, and selected parameters of mucosal immunity in the chicken jejunum.

Effects of exercise in hot and humid conditions and bovine colostrum on salivary immune markers.

The purpose of this study was to examine the effects of exercise in a hot and humid environment on salivary lactoferrin and lysozyme. A secondary aim was to quantify the effects of 14-day bovine colostrum (BC) supplementation on salivary lactoferrin and lysozyme at rest and following exercise in hot and humid conditions. Using a randomized, double-blind, and counterbalanced design, ten males (20±2 years, VO2max 55.8±3.7mLkg-1min-1, 11.8±2.7% body fat) ran for 46±7.7minat 95% of ventilatory threshold in a 40°C and 50% RH environment after 14-days of supplementation with either BC or placebo. Saliva was collected pre, post, 1-h, and 4-h post exercise, and was analyzed for lactoferrin and lysozyme using ELISA. There was an immediate increase in the concentration and secretion rate of lactoferrin and lysozyme (p<0.05) with exercise, but BC had no effect (p>0.05). Saliva flow rate was not different between conditions [(PLA: pre: 0.54±0.3, post: 0.44±0.3, 1-h: 0.67±0.3, 4-h: 1.0±0.4mLmin-1); (BC: pre: 0.58±0.2, post: 0.37±0.1, 1-h: 0.63±0.2, 4-h: 0.83±0.4mLmin-1)]. There were no differences in thermoregulatory markers (core temperature or physiological strain index) between BC and placebo trials. Interestingly, exercise-induced heat stress did not impair mucosal immune parameters, instead participants showed a transient increase in salivary lactoferrin and lysozyme. Further, 14-day BC supplementation had no effect on mucosal immunity at any time point.

Sublingual Omp16-driven redirection of the allergic intestinal response in a pre-clinical model of food allergy.

IgE-mediated food allergy remains a significant and growing worldwide problem. Sublingual immunotherapy (SLIT) shows an excellent safety profile for food allergy, but the clinical efficacy needs to be improved. This study assessed the effects of the Toll-like receptor 4 agonist outer membrane protein (Omp) 16 from Brucella abortus combined with cow´s milk proteins (CMP) through the sublingual route to modulate cow's milk allergy in an experimental model. Mice sensitized with cholera toxin and CMP were orally challenged with the allergen to elicit hypersensitivity reactions. Then, mice were treated with a very low amount of CMP along with Omp16 as a mucosal adjuvant, and finally, animals were re-exposed to CMP. Systemic and mucosal immune parameters were assessed in vivo and in vitro. We found that the sublingual administration of Omp16+CMP induced a buccal Th1 immune response that modulated the intestinal allergic response with the suppression of symptoms, reduction of IgE and IL-5, and up-regulation of IgG2a and IFN-γ. The adoptive transfer of submandibular IFN-γ-producing α4β7+ CD4+ and CD8+ cells conferred protection against allergic sensitization. The use of Omp16+CMP promoted enhanced protection compared to CMP alone. In conclusion, Omp16 represents a promising mucosal adjuvant that can be used to improve the clinical and immune efficacy of SLIT for food allergy.