Cell Wall Extract Research Articles

Effects of feeding mycotoxin-contaminated diets and the use of an adsorbent on the intake, digestibility, rumen fermentation, nitrogen balance and physiological parameters in the blood of Nellore steers

The study objective was to investigate the effects of mycotoxin contaminated diets and the use of an adsorbent (yeast cell wall extract; YCWE) on the intake, digestibility, rumen fermentation, nitrogen balance and physiological parameters in the blood of Nellore steers. Eight rumen-cannulated Nellore steers (initial BW = 417 ± 42 kg) were used in a 4 × 4 replicated Latin square design. A 2 × 2 factorial treatment structure was used to investigate the effects of mycotoxin contamination of the diet, the use of a mycotoxin adsorbent and their interactions. The dietary contamination consisted of: (1) diet without mycotoxins (CTRL), and (2) control diet added mycotoxins (MYCOT). The second factor was: (1) absence (YCWE–) or (2) presence (YCWE+) of YCWE. Mycotoxin contamination negatively affected dry matter intake during the first week of treatment application (P = 0.05) and tended to lower intake during the sampling period (P = 0.08). MYCOT resulted in lower (P = 0.03) digestibility of neutral detergent fiber and tended to lower (P = 0.08) ruminal pH compared with CTRL. There was MYCOT × YCWE interaction on the proportion of isovalerate (P < 0.01) and trend on the proportion of valerate (P = 0.08) in the rumen. There was also an effect of MYCOT (P = 0.04) and a trend of YCWE (P = 0.10) on the proportion of isobutyrate. Animals received MYCOT treatments had higher N excretion in the urine (P = 0.01), and consequently lower N retention (P = 0.05). There was MYCOT × YCWE interaction effect (P = 0.04) on the serum glucose concentration, where the MYCOT YCWE– treatment had a higher glucose concentration than the CTRL YCWE–, and the use of YCWE in MYCOT diet resulted in a concentration similar to CTRL treatments. The use of YCWE resulted in higher (P = 0.03) serum concentration of total proteins and lower (P < 0.01) proportion of ceruloplasmin. Animals fed mycotoxins had a lower (P < 0.01) proportion of IgA. MYCOT × YCWE effects (P < 0.01) on hemoglobin concentration and hematocrit were observed, where MYCOT had lower concentrations than the control and the use of YCWE in the contaminated diet resulted in values similar to CTRL. Animals fed mycotoxins tended to have lower (P = 0.08) number of lymphocytes and had lower (P = 0.02) lymphocytes: neutrophils ratios. This study suggests that mycotoxins may have negative impacts on certain physiological parameters that can influence health and performance of beef cattle, and the use of YCWE can mitigate some of these negative changes.

Humanized IGHA1 Mouse Induced by Lactobacillus casei Cell Wall Extract: A Novel Galactose-Deficient Immunoglobulin A1 (IgA1) Elevated Mouse Model of IgA Nephropathy

Humanized IGHA1 Mouse Induced by Lactobacillus casei Cell Wall Extract: A Novel Galactose-Deficient Immunoglobulin A1 (IgA1) Elevated Mouse Model of IgA Nephropathy

Use of Yeast Cell Wall Extract for Growing Pigs Consuming Feed Contaminated with Mycotoxins below or above Regulatory Guidelines: A Meta-Analysis with Meta-Regression.

Using a random-effects meta-analysis, the performance of growing pigs under a mycotoxin challenge (MT) with or without supplementation of yeast cell wall extract (YCWE, Mycosorb®, Alltech Inc.) was evaluated. Both MT and YCWE were also compared to animal controls not receiving mycotoxins (CTRL). Meta-regression was used to further explore the impacts of MT at/below (category 1) or above (category 2) global regulatory guidelines. Following the screening, 23 suitable references (30 mycotoxin treatments) were used. Overall, MT lowered average daily gain (ADG, p < 0.001) and average daily feed intake (ADFI, p < 0.0001) from CTRL by -84 and -165 g, respectively. Inclusion of YCWE during mycotoxin challenges (YCWE+MT, average 2.1 kg/ton) tended to result in greater ADG (+17 g, p = 0.068) compared to MT treatments. The gain-to-feed ratio (G:F) was not impacted by MT or YCWE+MT. Further investigation by meta-regression revealed that pigs fed MT in category 1 had lower ADG (-78.5 g, p < 0.001) versus CTRL, while YCWE+MT had higher ADG (+48 g, p < 0.001) over MT and was similar to CTRL. The ADFI was not impacted, although YCWE+MT had ADFI values similar to the CTRL. In category 2, ADG and ADFI of pigs fed MT were lower than CTRL (-85.1 and -166 g, respectively, p < 0.0001), with a tendency for YCWE+MT to result in higher ADFI (+25.3 g, p = 0.062). In summary, the inclusion of YCWE provided benefits to performance during common mycotoxin challenge levels (at or below regulatory guidelines).

Reduced synthesis of phospho-polysaccharide in Lactococcus as a strategy to evade phage infection

Lactococcus spp. are applied routinely in dairy fermentations and their consistent growth and associated acidification activity is critical to ensure the quality and safety of fermented dairy foods. Bacteriophages pose a significant threat to such fermentations and thus it is imperative to study how these bacteria may evade their viral predators in the relevant confined settings. Many lactococcal phages are known to specifically recognise and bind to cell wall polysaccharides (CWPSs) and particularly the phospho-polysaccharide (PSP) side chain component that is exposed on the host cell surface. In the present study, we generated derivatives of a lactococcal strain with reduced phage sensitivity to establish the mode of phage evasion. The resulting mutants were characterized using a combination of comparative genome analysis, microbiological and chemical analyses. Using these approaches, it was established that the phage-resistant derivatives incorporated mutations in genes within the cluster associated with CWPS biosynthesis resulting in growth and morphological defects that could revert when the selective pressure of phages was removed. Furthermore, the cell wall extracts of selected mutants revealed that the phage-resistant strains produced intact PSP but in significantly reduced amounts. The reduced availability of the PSP and the ability of lactococcal strains to revert rapidly to wild type growth and activity in the absence of phage pressure provides Lactococcus with the means to survive and evade phage attack.

Effects of probiotic and yeast extract supplementation on oxidative stress, inflammatory response, and growth in weaning Saanen kids.

This study aimed to investigate the effects of probiotic and yeast extract supplementation on the metabolic, immune, and oxidative status of Sannen goat kids during the weaning challenge. Forty goat kids were randomly assigned to four groups: a probiotic group (Pr) (basal diet + mixture of Bacillus subtilis, Bacillus lechiniformis, Streptococcus Thermophilis, and Enterococcus faecium), a yeast cell wall extract group (YC) (basal diet + Saccharomyces cerevisiae), a probiotic and yeast cell wall extract group (Pr + YC) (basal diet + mixture of probiotic and yeast cell wall extract), and a control group (basal diet). Treatments were administered 21 days prior to weaning (80 ± 2 days of life) until 21 days post-weaning except for the control group. Blood samples were collected at four different time points, including 21 days before weaning, 2 days post-weaning (weaning time), 7 days post-weaning, and 21 days post-weaning. Average levels of triiodothyronine, thyroxine, total protein (TP), albumin, globulin, blood urea nitrogen (BUN), total antioxidant capacity (TAC), serum adenosine deaminase (ADA), nitric oxide (NO), ferritin, glucose, cortisol, triglyceride, non-esterified fatty acid (NEFA), Β-hydroxybutyric acid (BHBA), and body weight were measured. The average levels of cortisol tended to be higher in the Pr group in comparison to the control group (P = 0.07) and the Pr + YC group (P = 0.10). NEFA was found to be higher and tended to be higher in the control group compared to the Pr + YC group (P > 0.001) and Pr group (P = 0.10), respectively. Additionally, the BHBA concentration was higher in the control group compared to the Pr group (P > 0.001). No differences were observed in the concentration of other measured parameters among the treatments. The concentration of cortisol tended to be higher (P = 0.10) at the weaning time as compared to the third sampling time. Furthermore, the concentration of TAC was observed to be higher (P > 0.01) at the weaning time in comparison to the third and fourth sampling times. The concentration of NO was higher (P > 0.01) at the third sampling time when compared to the first sampling time. A reduction in NEFA and BHBA levels may suggest an improvement in the metabolic status of the supplemented animals during the weaning challenge. However, supplementation with probiotics and yeast cell wall extract did not appear to have an effect on the oxidative status of the animals. The increase in TAC and NO levels observed during the weaning time may indicate an increase in oxidative stress during this period.

Identification and Quantification of Monosaccharides from Fungal Cell Walls and Exopolysaccharides by Gas Chromatography Coupled to Mass Spectrometry.

The fungal cell wall and secreted exopolysaccharides play an important role in the interactions between fungi and their environment. Despite their central role in fungal biology, ecology, and host-pathogen interactions, the composition of these polymers and their synthetic pathways are not well understood. The protocols presented in this article describe an approach to isolate fungal cell wall polysaccharides and to identify and quantify the monosaccharide composition of these polymers by gas chromatography-mass spectrometry (GC-MS). © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: O-methyl trimethylsilyl monosaccharide derivatives composition analysis by GC-MS Support Protocol: Fungal cell wall extraction.

Platelets exacerbate cardiovascular inflammation in a murine model of Kawasaki disease vasculitis.

Kawasaki disease (KD) is the leading cause of acquired heart disease among children. Increased platelet counts and activation are observed during the course of KD, and elevated platelet counts are associated with higher risks of developing intravenous immunoglobulin resistance and coronary artery aneurysms. However, the role of platelets in KD pathogenesis remains unclear. Here, we analyzed transcriptomics data generated from the whole blood of patients with KD and discovered changes in the expression of platelet-related genes during acute KD. In the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis, LCWE injection increased platelet counts and the formation of monocyte-platelet aggregates (MPAs), upregulated the concentration of soluble P-selectin, and increased circulating thrombopoietin and interleukin 6 (IL-6). Furthermore, platelet counts correlated with the severity of cardiovascular inflammation. Genetic depletion of platelets (Mpl-/- mice) or treatment with an anti-CD42b antibody significantly reduced LCWE-induced cardiovascular lesions. Furthermore, in the mouse model, platelets promoted vascular inflammation via the formation of MPAs, which likely amplified IL-1B production. Altogether, our results indicate that platelet activation exacerbates the development of cardiovascular lesions in a murine model of KD vasculitis. These findings enhance our understanding of KD vasculitis pathogenesis and highlight MPAs, which are known to enhance IL-1B production, as a potential therapeutic target for this disorder.

Pectolytic enzyme treatment partially degrades an arabinogalactan protein–rhamnogalacturonan I–xyloglucan co-polymer in red wine as characterised using epitope mass profiling

Polysaccharides are important metabolites in red wine but are challenging to separate from yeast-derived mannoproteins, and costly to identify using sialylation and gas chromatography. Affinity and gel permeation chromatography was combined with immunodetection of various specific plant cell wall polysaccharide epitopes to understand this complex mixture of extracted cell wall polymers. A survey of Cabernet Sauvignon wines produced with and without pectolytic enzymes suggested that enzyme-treated wines have fewer polysaccharides in the 85–105 kDa and 1050–6000 kDa ranges. When yeast-derived mannoproteins are excluded (15.3% of total), pectolytic enzyme treatment was shown to alter the molecular weight wine polysaccharide composition between the 100–1000 kDa ranges. Furthermore, ELISA data suggested that many of the soluble polysaccharides in the 300–1000 kDa range are an arabinogalactan protein–rhamnogalacturonan I–xyloglucan co-polymer. This is the first report to use ELISA to identify changes in specific polysaccharide classes during enzyme preparation used in wine maceration.

The activation of CaN/NFAT signaling pathway in macrophages aggravated Lactobacillus casei cell wall extract-induced Kawasaki disease vasculitis

ObjectivesBy using GWAS(genome-wide association studies) and linkage disequilibrium analysis to investigate the susceptibility genes of KD(Kawasaki disease), previous studies have identified that the CaN(calcineurin)-NFAT(the nuclear factor of activated T cell) signal pathway were significantly associated with susceptibility to KD. However, little is known about the molecular basis of the CaN/NFAT pathway involved in KD. Therefore, in our study we investigate the role of Ca2+/CaN/NFAT signaling pathway in macrophages in vitro and in vivo on coronary artery lesions induced by LCWE (Lactobacillus casei cell wall extract). Methods and resultsWe observed that LCWE could increase the expression of NFAT1 and NFAT2 in macrophages in vitro, and also enhance the transcriptional activity of NFAT by promoting the nucleus translocation. Similarly, in LCWE-induced mice model, the expression of NFAT1 and NFAT2 and associated proinflammatory factors were increased significantly. In addition, by knocking down or overexpressing NFAT1 or NFAT2 in macrophages, the results indicated that NFAT signaling pathway mediated LCWE-induced immune responses in macrophages and regulated the synthesis of IL(interleukin)-6, IL-1β and TNF(tumor necrosis factor)-α in LCWE-induced macrophage activation. As well, we found that this process could be suppressed by CaN inhibitor CsA(cyclosporinA). ConclusionsTherefore, the CaN/NFAT signaling pathway mediated LCWE-induced immune responses in macrophages, and also participated in the LCWE-induced CALs(coronary artery lesions). And also the inhibitory effect of CsA in LCWE-induced cell model towards a strategy to modulate the CaN/NFAT pathway during the acute course of KD might be helpful in alleviate KD-induced CALs.

Optimisation and modelling of ultrasonic-assisted extraction of canthaxanthin from Chromochloris zofingiensis using eutectic solvents

Carotenoids are well-known bioactive compounds and high-value nutritional molecules. Chromochloris zofingiensis, a unicellular green alga, is a promising source of commercial carotenoids owing to its robust growth, easy cultivation, and facile scale-up. However, this microalga has a very rigid three-layered cell wall that hinders extraction. Meanwhile, traditional extraction methods are complicated and cause serious pollution. To address these issues, a eutectic solvent (ES) was identified from 15 candidates for the ultrasonic-assisted extraction of canthaxanthin from C. zofingiensis for the first time. Remarkably, this hydrophobic ES comprising octanoic and decanoic acid displayed novel dual functions of breaking the cell wall and carotenoid extraction. Under the optimised extraction conditions obtained using a response surface methodology (ultrasound at 50 ℃ for 49 min, octanoic acid-to-decanoic acid molar ratio of 2.3:1, and solid-to-solvent ratio of 66.2 mg/mL), the maximum yield of canthaxanthin (60.5 μg/mL) was equal or superior to that using traditional organic extractant after grinding to break the cell wall. Furthermore, only the ES was employed as the extraction solvent, and the canthaxanthin content obtained by pre-grinding under the same condition (70.4 μg/mL) was much higher than that of grinding and extraction with ethanol (62.2 μg/mL). Possible mechanisms of cell wall breakage and component extraction were investigated based on extraction kinetic analysis, molecular dynamics simulation, and scanning electron microscopy observation. This ES is non-volatile and environmentally friendly, making it a simple, sustainable, and effective alternative extractant for carotenoids in microalga. There is considerable potential for its industrial-scale development and applications in various fields such as food, medicine, and cosmetics.

Yeast cell wall extracts from Saccharomyces cerevisiae varying in structure and composition differentially shape the innate immunity and mucosal tissue responses of the intestine of zebrafish (Danio rerio).

With the rising awareness of antimicrobial resistance, the development and use of functional feed additives (FFAs) as an alternative prophylactic approach to improve animal health and performance is increasing. Although the FFAs from yeasts are widely used in animal and human pharma applications already, the success of future candidates resides in linking their structural functional properties to their efficacy in vivo. Herein, this study aimed to characterise the biochemical and molecular properties of four proprietary yeast cell wall extracts from S. cerevisiae in relation to their potential effect on the intestinal immune responses when given orally. Dietary supplementation of the YCW fractions identified that the α-mannan content was a potent driver of mucus cell and intraepithelial lymphocyte hyperplasia within the intestinal mucosal tissue. Furthermore, the differences in α-mannan and β-1,3-glucans chain lengths of each YCW fraction affected their capacity to be recognised by different PRRs. As a result, this affected the downstream signalling and shaping of the innate cytokine milieu to elicit the preferential mobilisation of effector T-helper cell subsets namely Th17, Th1, Tr1 and FoxP3+-Tregs. Together these findings demonstrate the importance of characterising the molecular and biochemical properties of YCW fractions when assessing and concluding their immune potential. Additionally, this study offers novel perspectives in the development specific YCW fractions derived from S. cerievisae for use in precision animal feeds.

Abstract 480: IL-33 Promotes Cardiovascular Lesions Development In A Mouse Model Of Kawasaki Disease

Kawasaki Disease (KD), a pediatric acute febrile illness and systemic vasculitis, is the leading cause of acquired heart diseases in children. Coronary artery aneurysms (CAAs) occur in up to 25% of untreated children, which is reduced to 5% with intravenous immunoglobulin (IVIG) treatment. However, up to 20% of KD patients are refractory to IVIG and at higher risk of CAAs, highlighting the need to characterize the mechanisms mediating KD vasculitis to develop more efficient therapies. IL-33 is released upon inflammation and tissue damage and exerts its effects by binding to its receptor ST2 ( IL1RL1 ). Levels of IL-33 are elevated in KD patients during the acute phase. However, how IL-33 contributes to the development of KD cardiovascular lesions remains unknown. Using the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis, we observed increased Il33 mRNA expression in hearts and abdominal aortas aneurysms of LCWE-injected mice. While ST2 was detected by immunofluorescence in the abdominal aortas of both control and LCWE-injected mice, IL-33 was mainly detected in tissues from LCWE-injected mice. Single-cell RNA-sequencing of abdominal aortas from LCWE-injected mice indicated that Il33 transcripts were expressed primarily by fibroblasts, endothelial cells, B cells, and vascular smooth muscle cells. In contrast, Il1rl1 was highly expressed by tissue infiltrating regulatory T cells, macrophages, eosinophils, and neutrophils. Blocking IL-33 with either anti-IL-33 or using Il33 -/- mice significantly attenuated LCWE-induced KD vasculitis. Our results indicate that IL-33 participates in LCWE-induced KD vasculitis in mice and could therapeutically be targeted to inhibit KD cardiovascular lesions.

IL-33 promotes cardiovascular lesions development in a mouse model of Kawasaki Disease

Abstract Kawasaki Disease (KD), a pediatric acute febrile illness and systemic vasculitis, is the leading cause of acquired heart diseases in children. Coronary artery aneurysms (CAAs) occur in up to 25% of untreated children, which is reduced to 5% with intravenous immunoglobulin (IVIG) treatment. However, up to 20% of KD patients are refractory to IVIG and at higher risk of CAAs, highlighting the need to characterize the mechanisms mediating KD vasculitis to develop more efficient therapies. IL-33 is released upon inflammation and tissue damage and exerts its effects by binding to its receptor ST2 (IL1RL1). Levels of IL-33 are elevated in KD patients during the acute phase. However, how IL-33 contributes to the development of KD cardiovascular lesions remains unknown. Using the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis, we observed increased Il33 mRNA expression in hearts and abdominal aortas aneurysms of LCWE-injected mice. While ST2 was detected by immunofluorescence in the abdominal aortas of both control and LCWE-injected mice, IL-33 was mainly detected in tissues from LCWE-injected mice. Single-cell RNA-sequencing of abdominal aortas from LCWE-injected mice indicated that Il33 transcripts were expressed primarily by fibroblasts, endothelial cells, B cells, and vascular smooth muscle cells. In contrast, Il1rl1 was highly expressed by tissue infiltrating regulatory T cells, macrophages, eosinophils, and neutrophils. Blocking IL-33 with either anti-IL-33 antibody or using Il33 −/−mice significantly attenuated LCWE-induced KD vasculitis. Our results indicate that IL-33 promotes LCWE-induced KD vasculitis in mice and could therapeutically be targeted to inhibit KD cardiovascular lesions.

Mercury increases IL-1β and IL-18 secretion and intensifies coronary arteritis in an animal model of Kawasaki disease.

Kawasaki disease (KD) is a multisystem vasculitis that predominantly targets the coronary arteries in young children. Epidemiological data suggest both environmental and genetic factors contribute to the susceptibility and severity of the disease. Mercury (Hg) is a known environmental pollutant and a Ca2+ signaling modulator. Ca2+ signaling regulates the activation of NLRP3 inflammasome. Using the Lactobacillus casei cell wall extract (LCWE) induced coronary arteritis mouse model of KD; we studied the effect of mercury on inflammasome activation and its impact on the immunopathogenesis of KD. Mercury enhances the expression of inflammasome activation resulting in caspase-1 mediated secretion of IL-1β and IL-18 cytokines. In vivo, the administration of mercury together with disease inducing LCWE exacerbates disease resulting in increased incidence and severity of coronary arteritis compared to LCWE alone. Mercury can act as a novel danger signal modulating Ca2+ signaling to increase IL-1β and IL-18 secretion and intensifies coronary arteritis in an animal model of KD.

Evaluation of the effects of dietary mycotoxin-degrading adsorbent on juvenile turbot (Scophthalmus maximus L.) fed aflatoxin B1-contaminated diets

This eight-week feeding trial was conducted to investigate whether adding yeast cell wall extract mixed with bacteria producing mycotoxin-degrading enzymes (YEMDE) to an aflatoxin B1 (AFB1)-contaminated diet affects the growth performance, liver health, antioxidant status, and intestinal microbiota status of juvenile turbot. A total of 480 fish were divided into four groups (three replicate tanks each group): basal diet (Control); Control diet supplemented with 100 μg/kg AFB1 (AFB1); and AFB1 supplemented with 500 mg/kg or 1000 mg/kg YEMDE (AFY500 and AFY1000, respectively). The results showed that a minor variation in growth performance was observed among all groups (P > 0.05). Compared to the Control diet, the AFB1 diet significantly deceased the activities of triglyceride and catalase in the serum (P < 0.05); Compared to the Control diet, the AFB1 diet significantly increased the gene expression of cyp3a and apoptosis-related genes (p53, Bax, caspase3, caspase7 and caspase9) (P < 0.05), reduced the expression of catalase in the liver (P < 0.05); In addition, the AFB1 diet negatively changed the communities of intestinal microbiota and down-regulated the abundance of some potential probiotics Bifidobacterium and Stenotrophomonas (P < 0.05). However, both the AFY500 and AFY1000 diets markedly recovered the antioxidant capacity, inhibited the apoptosis of hepatocytes, and improved the communities of intestinal microbiota (P < 0.05). More positive effects were observed in the AFY1000 group. Compared to the AFB1 diet, the AFY1000 diet markedly increased the abundance of some potential beneficial bacteria in the intestine, such as Faecalibacterium and Lachnoanaerobaculum (P < 0.05). In conclusion, dietary YEMDE can effectively reduce the harmful impacts caused by AFB1 on turbot, and in particular, it had beneficial effects on the communities of intestinal microbiota. It is promising to use YEMDE to control AFB1 contamination in fish feeds.

Effect of ultrasound-assisted cold plasma pretreatment on cell wall polysaccharides distribution and extraction of phenolic compounds from hyssop (Hyssopus officinalis L.)

Hyssopus officinalis L (Hyssop) is a good source of phenolic compounds. However, conventional methods for extraction of these compounds typically take a long time and have relatively low recovery rates. This study focused on cold atmospheric plasma (CAP) pretreatment and investigated its effects on the ultrasound-assisted extraction (UAE) of phenolic compounds from hyssop. Hyssop was treated at dielectric barrier discharge plasma with air and nitrogen gases for 5, 10, and 15 min. Optical emission spectroscopy was used to evaluate present active species in the plasma. The water contact angle changes, cell wall polysaccharides distribution, and structural variations of the treated samples were determined after treatment. Antioxidant activity and total phenolic contents (TPC) of the extracts were also evaluated. The results showed that CAP treatment reduced the contact angle making surface more hydrophilic. Compared with hyssop, overall no significant changes in the basic structure of all treated samples or the formation of new functional groups were recognized. In addition, CAP pretreatment before UAE increased the antioxidant activity of extracts according to the FRAP assay than the un-pretreated sample and conventional solvent extraction method. Also, TPC increased in samples treated with nitrogen plasma.

Comparative Assessment of Different Yeast Cell Wall-Based Mycotoxin Adsorbents Using a Model- and Bioassay-Based In Vitro Approach.

Frequently reported occurrences of deoxynivalenol (DON), beauvericin (BEA), and, to a lesser extent, ochratoxin A (OTA) and citrinin (CIT) in ruminant feed or feedstuff could represent a significant concern regarding feed safety, animal health, and productivity. Inclusion of yeast cell wall-based mycotoxin adsorbents in animal feeds has been a common strategy to mitigate adverse effects of mycotoxins. In the present study, an in vitro approach combining adsorption isotherm models and bioassays was designed to assess the efficacy of yeast cell wall (YCW), yeast cell wall extract (YCWE), and a postbiotic yeast cell wall-based blend (PYCW) products at the inclusion rate of 0.5% (w/v) (ratio of adsorbent mass to buffer solution volume). The Hill's adsorption isotherm model was found to best describe the adsorption processes of DON, BEA, and CIT. Calculated binding potential for YCW and YCWE using the Hill's model exhibited the same ranking for mycotoxin adsorption, indicating that BEA had the highest adsorption rate, followed by DON and CIT, which was the least adsorbed. PYCW had the highest binding potential for BEA compared with YCW and YCWE. In contrast, the Freundlich isotherm model presented a good fit for OTA adsorption by all adsorbents and CIT adsorption by PYCW. Results indicated that YCW was the most efficacious for sequestering OTA, whereas YCWE was the least efficacious. PYCW showed greater efficacy at adsorbing OTA than CIT. All adsorbents exhibited high adsorption efficacy for BEA, with an overall percentage average of bound mycotoxin exceeding 60%, whereas moderate efficacies for the other mycotoxins were observed (up to 37%). Differences in adsorbent efficacy of each adsorbent significantly varied according to experimental concentrations tested for each given mycotoxin (p < 0.05). The cell viability results from the bioassay using a bovine mammary epithelial cell line (MAC-T) indicated that all tested adsorbents could potentially mitigate mycotoxin-related damage to bovine mammary epithelium. Results from our studies suggested that all tested adsorbents had the capacity to adsorb selected mycotoxins in vitro, which could support their use to mitigate their effects in vivo.

Mycobacterium tuberculosis Cell Wall Antigens Induce the Formation of Immune Complexes and the Development of Vasculitis in an Experimental Murine Model.

Tuberculosis (TB) of the central nervous system (CNS) presents high mortality due to brain damage and inflammation events. The formation and deposition of immune complexes (ICs) in the brain microvasculature during Mycobacterium tuberculosis (Mtb) infection are crucial for its pathobiology. The relevance of ICs to Mtb antigens in the pathogenesis of CNS-TB has been poorly explored. Here, we aimed to establish a murine experimental model of ICs-mediated brain vasculitis induced by cell wall antigens of Mtb. We administered a cell wall extract of the prototype pathogenic Mtb strain H37Rv to male BALB/c mice by subcutaneous and intravenous routes. Serum concentration and deposition of ICs onto blood vessels were determined by polyethylene glycol precipitation, ELISA, and immunofluorescence. Histopathological changes in the brain, lung, spleen, liver, and kidney were evaluated by hematoxylin and eosin staining. Our results evidenced that vasculitis developed in the studied tissues. High serum levels of ICs and vascular deposition were evident in the brain, lung, and kidneys early after the last cell wall antigen administration. Cell wall Mtb antigens induce strong type III hypersensitivity reactions and the development of systemic vasculitis with brain vascular changes and meningitis, supporting a role for ICs in the pathogenesis of TB.

Increased Myosin light chain 9 expression during Kawasaki disease vasculitis.

Kawasaki disease (KD) is an acute systemic vasculitis that predominantly afflicts children. KD development is known to be associated with an aberrant immune response and abnormal platelet activation, however its etiology is still largely unknown. Myosin light chain 9 (Myl9) is known to regulate cellular contractility of both non-muscle and smooth muscle cells, and can be released from platelets, whereas any relations of Myl9 expression to KD vasculitis have not been examined. Plasma Myl9 concentrations in KD patients and children with febrile illness were measured and associated with KD clinical course and prognosis. Myl9 release from platelets in KD patients was also evaluated in vitro. Myl9 expression was determined in coronary arteries from Lactobacillus casei cell wall extract (LCWE)-injected mice that develop experimental KD vasculitis, as well as in cardiac tissues obtained at autopsy from KD patients. Plasma Myl9 levels were significantly higher in KD patients during the acute phase compared with healthy controls or patients with other febrile illnesses, declined following IVIG therapy in IVIG-responders but not in non-responders. In vitro, platelets from KD patients released Myl9 independently of thrombin stimulation. In the LCWE-injected mice, Myl9 was detected in cardiac tissue at an early stage before inflammatory cell infiltration was observed. In tissues obtained at autopsy from KD patients, the highest Myl9 expression was observed in thrombi during the acute phase and in the intima and adventitia of coronary arteries during the chronic phase. Thus, our studies show that Myl9 expression is significantly increased during KD vasculitis and that Myl9 levels may be a useful biomarker to estimate inflammation and IVIG responsiveness to KD.

SIGIRR-caspase-8 signaling mediates endothelial apoptosis in Kawasaki disease

BackgroundKawasaki disease (KD) is a kind of vasculitis with unidentified etiology. Given that the current diagnosis and therapeutic strategy of KD are mainly dependent on clinical experiences, further research to explore its pathological mechanisms is warranted.MethodsEnzyme linked immunosorbent assay (ELISA) was used to measure the serum levels of SIGIRR, TLR4 and caspase-8. Western blotting was applied to determine protein levels, and flow cytometry was utilized to analyze cell apoptosis. Hematoxylin eosin (HE) staining and TUNEL staining were respectively used to observe coronary artery inflammation and DNA fragmentation.ResultsIn this study, we found the level of SIGIRR was downregulated in KD serum and KD serum-treated endothelial cells. However, the level of caspase-8 was increased in serum from KD patients compared with healthy control (HC). Therefore, we hypothesized that SIGIRR-caspase-8 signaling may play an essential role in KD pathophysiology. In vitro experiments demonstrated that endothelial cell apoptosis in the setting of KD was associated with caspase-8 activation, and SIGIRR overexpression alleviated endothelial cell apoptosis via inhibiting caspase-8 activation. These findings were also recapitulated in the Candida albicans cell wall extracts (CAWS)-induced KD mouse model.ConclusionOur data suggest that endothelial cell apoptosis mediated by SIGIRR-caspase-8 signaling plays a crucial role in coronary endothelial damage, providing potential targets to treat KD.