Allergenic Shrimp Tropomyosin Distinguishes from a Non-Allergenic Chicken Homolog by Pronounced Intestinal Barrier Disruption and Downstream Th2 Responses in Epithelial and Dendritic Cell (Co)Culture.

BACKGROUND: Tropomyosins (TM) from vertebrates are generally non-allergenic, while invertebrate homologs are potent pan-allergens. This study aims to compare the risk of sensitization between chicken TM and shrimp TM through affecting the intestinal epithelial barrier integrity and type 2 mucosal immune activation. METHODS: Epithelial activation and/or barrier effects upon exposure to 2-50 µg/mL chicken TM, shrimp TM or ovalbumin (OVA) as a control allergen, were studied using Caco-2, HT-29MTX, or HT-29 intestinal epithelial cells. Monocyte-derived dendritic cells (moDC), cocultured with HT-29 cells or moDC alone, were exposed to 50 µg/mL chicken TM or shrimp TM. Primed moDC were cocultured with naïve Th cells. Intestinal barrier integrity (TEER), gene expression, cytokine secretion and immune cell phenotypes were determined in these human in vitro models. RESULTS: Shrimp TM, but not chicken TM or OVA exposure, profoundly disrupted intestinal barrier integrity and increased alarmin genes expression in Caco-2 cells. Proinflammatory cytokine secretion in HT-29 cells was only enhanced upon shrimp TM or OVA, but not chicken TM, exposure. Shrimp TM enhanced the maturation of moDC and chemokine secretion in the presence or absence of HT-29 cells, while only in the absence of epithelial cells chicken TM activated moDC. Direct exposure of moDC to shrimp TM increased IL13 and TNFα secretion by Th cells cocultured with these primed moDC, while shrimp TM exposure via HT-29 cells cocultured with moDC sequentially increased IL13 expression and IL4 secretion in Th cells. CONCLUSIONS: Shrimp TM, but not chicken TM, disrupted the epithelial barrier while triggering type 2 mucosal immune activation, both of which are key events in allergic sensitization.

Bioactive Dairy-Fermented Products and Phenolic Compounds: Together or Apart.

Fermented dairy products (e.g., yogurt, kefir, and buttermilk) are significant in the dairy industry. They are less immunoreactive than the raw materials from which they are derived. The attractiveness of these products is based on their bioactivity and properties that induce immune or anti-inflammatory processes. In the search for new solutions, plant raw materials with beneficial effects have been combined to multiply their effects or obtain new properties. Polyphenols (e.g., flavonoids, phenolic acids, lignans, and stilbenes) are present in fruit and vegetables, but also in coffee, tea, or wine. They reduce the risk of chronic diseases, such as cancer, diabetes, or inflammation. Hence, it is becoming valuable to combine dairy proteins with polyphenols, of which epigallocatechin-3-gallate (EGCG) and chlorogenic acid (CGA) show a particular predisposition to bind to milk proteins (e.g., α-lactalbumin ß-lactoglobulin, αs1-casein, and κ-casein). Reducing the allergenicity of milk proteins by combining them with polyphenols is an essential issue. As potential 'metabolic prebiotics', they also contribute to stimulating the growth of beneficial bacteria and inhibiting pathogenic bacteria in the human gastrointestinal tract. In silico methods, mainly docking, assess the new structures of conjugates and the consequences of the interactions that are formed between proteins and polyphenols, as well as to predict their action in the body.

Immunoreactive proteins of Capsicum-based spices as a threat to human health: mass spectrometry analysis and in silico mapping.

Dietary patterns are changing severely, especially the consumption of highly processed foods with lots of spices is increasing, carrying an increased risk of immediate hypersensitivity (type I), in sensitised individuals, due to the possible presence of allergens, especially the hidden ones. Paprika is a fruit of the Capsicum genus, which belongs to the Solanaceae family and is commonly consumed fresh or as a spice. Despite recorded cases of anaphylaxis, its allergenicity has yet to be clearly investigated. In this study, we research to identify proteins that could trigger a severe allergic reaction in patients with an equivocal clinical picture. Two types of protein extracts extracted from 3 different paprika spices were immunoblotted with sera from patients with severe allergic symptoms, presumably to paprika. Proteins from the IgE reactive bands obtained were subjected to LC-MS/MS identification and then in silico analysis to assess their possible sensitising capacity and proinflammatory potential using online tools. The spices were shown to contain a number of incompletely investigated highly immunoreactive allergenic proteins, including proteins of foreign origin (contaminants), the presence of which can stimulate inflammatory mechanisms and cross-reactivity with other food allergens, which can threaten life and health and should be investigated in detail.

Glycation of Whey Proteins Increases the Ex Vivo Immune Response of Lymphocytes Sensitized to ß-Lactoglobulin.

Glycation is a spontaneous reaction accompanying the thermal processing and storage of food. It can lead to changes in the allergenic and immunogenic potential of protein. This study aimed to evaluate the effect of the glycation of α-lactalbumin and ß-lactoglobulin (ß-lg) on the ex vivo response of ß-lg sensitized lymphocytes. C57BL/6 mice were immunized intragastrically (i-g) or intraperitoneally (i-p) with ß-lg. The humoral response of the groups differed only with respect to the IgE level of the i-p group. Cellular response was studied after stimulation with antigen variants. The lymphocytes from the i-g/group mesenteric lymph nodes, stimulated with ß-lg before and after glycation, presented a higher percentage of CD4 and CD8 T cells compared to the i-p/group. The cytokine profile of the i-p/group splenocytes stimulated with antigens showed elevated levels of pro-inflammatory IL-17A regardless of protein modification. In conclusion, the ex vivo model proved that the glycation process does not reduce protein immunogenicity.

Side Streams of Vegetable Processing and Its Bioactive Compounds Support Microbiota, Intestine Milieu, and Immune System.

The industry of vegetable processing generates large amounts of by-products, which often emerge seasonally and are susceptible to microbial degradation. Inadequate management of this biomass results in the loss of valuable compounds that are found in vegetable by-products that can be recovered. Considering the possibility of using waste, scientists are trying to reuse discarded biomass and residues to create a product of higher value than those processed. The by-products from the vegetable industry can provide an added source of fibre, essential oils, proteins, lipids, carbohydrates, and bioactive compounds, such as phenolics. Many of these compounds have bioactive properties, such as antioxidative, antimicrobial, and anti-inflammatory activity, which could be used, especially in the prevention or treatment of lifestyle diseases connected with the intestinal milieu, including dysbiosis and immune-mediated diseases resulting in inflammation. This review summarises the key aspects of the health-promoting value of by-products and their bioactive compounds derived from fresh or processed biomass and extracts. In this paper, the relevance of side streams as a source of beneficial compounds with the potential for promoting health is considered, particularly their impact on the microbiota, immune system, and gut milieu because all of these fields interact closely to affect host nutrition, prevent chronic inflammation, and provide resistance to some pathogens.

Phytate Hydrolysate Differently Modulates the Immune Response of Human Healthy and Cancer Colonocytes to Intestinal Bacteria.

(1) Phytic acid (PA) is a component of cereal seeds and legumes, therefore its consumption is much higher in a vegan and vegetarian diet compared to a conventional diet. The diet is the main driver of metabolic activity of gut microbiota, therefore, the ability to degrade phytates by the microbiota of vegans significantly exceeds that of the gut microbiota of omnivores. The aim of the study was to investigate the early phase of the immune response of colonocytes treated with an enzymatic hydrolysate of phytic acid (hPA120) and gut bacteria. (2) Cell lines derived from healthy (NCM460D) and cancer (HCT116) colonic tissue and fecal bacteria from vegan (V) and omnivorous (O) donors were investigated. Fecal bacteria were grown in mucin and phytic acid supplemented medium. Cultured bacteria (BM) were loaded onto colonocytes alone (V BM and O BM) or in combination with the phytate hydrolysate (V BM + hPA120 and O BM + hPA120). After a treatment of 2 h, bacterial adhesion, secretion of cytokines, and the expression of genes and proteins important for immune response were determined. (3) All bacteria-treated colonocytes increased the expression of IL8 compared to controls. The significant increase of the secreted IL-8 (p < 0.01) in both cell lines was observed for O BM and O BM + hPA120. The increase of TNF, IL-1ß, and IL-10 secretion in healthy colonocytes (V BM alone and with hPA120 treatments; p < 0.05) and for TNF and IL-10 in cancer cells (treatments except O BM + hPA120 and V BM, respectively; p > 0.05) were stated. A comparison of solely the effect of hPA120 on bacteria-treated colonocytes (BM vs. BM + hPA120) showed that hPA120 decreased expression of NFkB1 and TNFR (p < 0.001) in healthy colonocytes. In cancer colonocytes, the expression of TLR4 and IL1R increased after BM + hPA120 treatment, whereas the secretion of IL-8 and MYD88 and TNFR expression decreased (p < 0.01). (4) The investigated hPA120 showed a differentiated modulatory activity on the immune response of healthy and cancer human colonocytes. Especially when analyzed independently on the gut bacteria origin, it reduced the proinflammatory response of HCT116 cells to gut bacteria, while being neutral for the bacteria-treated healthy colonocytes.

The Immune System Response to 15-kDa Barley Protein: A Mouse Model Study.

Barley (Hordeum vulgare L.) proteins are taxonomically homologous to wheat proteins and react with sera from patients with baker's asthma. In the current work, the crude extract of barley proteins was divided into six fractions on DEAE-Sepharose. Their immunoreactivity in reacting with sera from patients with a confirmed food allergy varied, and the 15-kDa fraction (B−FrVI) showed the strongest response. In silico analysis confirmed that 15-kDa B-FrVI protein belongs to the trypsin/amylase inhibitor family and to a group of MHC type II allergens. In the next step, the immunogenicity of the B-FrVI was examined in a mouse model. It was shown that, compared to the PBS group, administration of B-FrVI to mice induced almost 2× higher amounts of specific IgG, ~217, and IgA ~29, as early as day 28 after immunization, regardless of the route (intraperitoneal or oral) of antigen administration (p < 0.0001). An ELISpot for B-cell responses confirmed it. Stimulation of mesenteric lymphocytes with pure B-FrVI significantly increased (p < 0.001) the proliferation of lymphocytes from all groups compared to cells growing in media only and stimulated with lyophilized beer. The experiments prove the strong immunogenicity of the 15-kDa B-FrVI protein and provide a basis for future studies of the allergenic nature of this protein.

The Manifold Bioactivity and Immunoreactivity of Microbial Proteins of Cow and Human Mature Milk in Late Lactation.

(1) Human milk (HM) is a source of many microorganisms, whose structure contains microbial protein (MP). In addition to the known health-promoting properties of HM, many activities, including immunoreactivity, may result from the presence of MP. Cow's milk (CM)-derived MP may be 10 times more abundant than MP derived from HM. (2) Raw cow's milk samples of Holstein and Jersey breeds, commercially available pasteurized milk, and milk from three human donors in the late lactation phase were subjected to chemical and microbiological analyzes. Microorganisms from the milk material were recovered, cultured, and their activities were tested. MPs were extracted and their immunoreactivity was tested with human high IgE pooled sera. The milk types were subjected to simulated digestion. Milk and microbial proteins were identified with LCMS and subjected to an in silico analysis of their activities. Their antioxidant potential was analysed with the DPPH method. (3) The MP of HM shows a stronger IgE and IgG immunoreactivity in the tests with human sera compared to the MP of CM (p = 0.001; p = 0.02, respectively). There were no significant differences between the microbes in the MP of different cattle breeds. The MS-identification and in silico tests of milk and microbial proteins confirmed the presence of MP with immunoreactivity and antioxidant potential. (4) MPs possess a broad bioactive effect, which was determined by an in silico tools. The balance between an MP's individual properties probably determines the raw material's safety, which undoubtedly requires further research.

Nutritional strategies for autophagy activation and health consequences of autophagy impairment.

OBJECTIVES: Currently, the plague of chronic diseases, such as overweight, obesity, diabetes, and cardiovascular diseases, is associated with chronic inflammation as an effect of homeostasis disbalance. One of the processes involved in homeostasis maintenance is autophagy, which is also referred to as self-eating or cellular recycling. Due to the correlation between the epidemic scale of chronic diseases and autophagy impairment, strategies for autophagy activation are urgently needed. METHODS: In this review, we comprehensively summarized the current data on autophagy types, dysfunction, associated diseases, and ways of activation available in scientific databases and published up until 2022. RESULTS: Our review indicates that impaired autophagy is associated with inflammatory bowel diseases, cancer, overweight, obesity, type I diabetes, diseases of the cardiovascular system, neurodegenerative diseases, depression, and anxiety. We highlight nutritional behavior as one of the factors behind autophagy induction and homeostasis restoration. CONCLUSIONS: Autophagy is involved in different dysfunctions and diseases; thus, activation strategies are urgently needed. A high potential in the prevention and therapies of chronic diseases by means of autophagy induction can be expected from nutritional behaviors. To date, most studies were carried out in vitro or in a murine model. Thus, further, well-designed, clinical trials are needed to provide the missing understanding of the nutritional potential to regulate specific signaling pathways that keep autophagy running smoothly.

Operational culture conditions determinate benzalkonium chloride resistance in L. monocytogenes-E. coli dual species biofilms.

Biofilms pose a serious challenge to the food industry. Higher resistance of biofilms to any external stimuli is a major hindrance for their eradication. In this study, we compared the growth dynamics and benzalkonium chloride (BAC) resistance of dual species Listeria monocytogenes-Escherichia coli 48 h biofilms formed on stainless steel (SS) coupons surfaces under batch and fed-batch cultures. Differences between both operational culture conditions were evaluated in terms of total viable adhered cells (TVAC) in the coupons during 48 h of the mixed-culture and of reduction of viable adhered cells (RVAC) obtained after BAC-treatment of a 48 h biofilm of L. monocytogenes-E. coli formed under both culture conditions. Additionally, epifluorescence microscopy (EFM) and confocal scanning microscopy (CLSM) permitted to visualize the 2D and 3D biofilms structure, respectively. Observed results showed an increase in the TVAC of both strains during biofilm development, being the number of E. coli adhered cells higher than L. monocytogenes in both experimental systems (p < 0.05). Additionally, the number of both strains were higher approximately 2.0 log CFU/coupon in batch conditions compared to fed-batch system (p < 0.05). On the contrary, significantly higher resistance to BAC was observed in biofilms formed under fed-batch conditions. Furthermore, in batch system both strains had a similar reduction level of approximately 2.0 log CFU/coupon, while significantly higher resistance of E. coli compared to L. monocytogenes (reduction level of 0.69 and 1.72 log CFU/coupon, respectively) (p < 0.05) was observed in fed-batch system. Microscopic image visualization corroborated these results and showed higher complexity of 2D and 3D structures in dual species biofilms formed in batch cultures. Overall, we can conclude that the complexity of the biofilm structure does not always imply higher resistance to external stimuli, and highlights the need to mimic industrial operational conditions in the experimental systems in order to better assess the risk associated to the presence of pathogenic bacterial biofilms.

OVA-Experienced CD4+ T Cell Transfer and Chicken Protein Challenge Affect the Immune Response to OVA in a Murine Model.

Chicken meat is often a major component of a modern diet. Allergy to chicken meat is relatively rare and occurs independently or in subjects allergic to ovalbumin (OVA). We examined the effect of adoptive transfer of OVA-CD4+ T cells on the immune response to OVA in mice fed chicken meat. Donor mice were injected intraperitoneally with 100 µg of OVA with Freund's adjuvant two times over a week, and CD4+ T cells were isolated from them and transferred to naïve mice (CD4+/OVA/ChM group), which were then provoked with OVA with FA and fed freeze-dried chicken meat for 14 days. The mice injected with OVA and fed chicken meat (OVA/ChM group), and sensitized (OVA group) and healthy (PBS group) mice served as controls. Humoral and cellular response to OVA was monitored over the study. The CD4+/OVA/ChM group had lowered levels of anti-OVA IgG and IgA, and total IgE. There were significant differences in CD4+, CD4+CD25+, and CD4+CD25+Foxp3+ T cells between groups. OVA stimulation decreased the splenocyte proliferation index and IFN-γ secretion in the CD4+/OVA/ChM group compared to the OVA group. IL-4 was increased in the OVA/ChM mice, which confirms allergenic potential of the egg-meat protein combination. Transfer of OVA-experienced CD4+ T cells ameliorated the negative immune response to OVA.

Phytate and Butyrate Differently Influence the Proliferation, Apoptosis and Survival Pathways in Human Cancer and Healthy Colonocytes.

The colonic epithelium is never exposed to a single factor, therefore studies on the effect of combinations of factors naturally and persistently present in the intestines are of special importance for understanding the phenomena occurring at this place. The aim of the study was to investigate the combined effect of 1 mM phytate and 1 mM butyrate (PA1B1) on cell lines derived from cancer (HCT116 and HT-29) and healthy (NCM460D) human colonic epithelium. Colorimetric and flow cytometry methods were used to determine the proliferation rate, cell cycle, and apoptosis. Selected markers of proliferation, inflammatory, and survival pathways were investigated at the mRNA and/or protein level. The combination of phytate and butyrate disturbed the cell cycle and triggered apoptosis and/or death in both studied cancer colonocytes to a higher extent compared to healthy colonocytes. Moreover, in healthy colonocytes, phytate activated the survival pathway without stimulation of inflammatory response. This may indicate that the response of healthy colonocytes to phytate protects colonic epithelium from the loss of integrity and tightness that would occur if inflammation developed. Based on the obtained results we postulate that studies on both cancer and/or healthy colonocytes should be carried out in the presence of butyrate as the permanent component of colonic contents. This should be of special importance when anti-proliferative/pro-apoptotic activity or inflammatory status of colonocytes is to be investigated.

The effect of lactic acid fermentation with different bacterial strains on the chemical composition, immunoreactive properties, and sensory quality of sweet buttermilk.

This paper describes the successful development of new low-immunoreactive buttermilk (BM)-based formulations which were fermented with 31 lactic acid bacteria (LAB) and Bifidobacterium strains. The aim of this study was to create a new formula, which can serve as potential candidates for the immunotherapy of allergy. Preparations were tested for their content of biologically active compounds, such as proteins, peptides, phospholipids, and short-chain fatty acids (SCFA), as well as for the survivability of LAB and sensory quality. The results showed that the BM was a matrix rich in nutritional components and displayed higher than expected susceptibility to the reduction of protein IgE-immunoreactivity (to 98%) and high bacterial-protecting capacity. The overall sensory quality of examined products was influenced by the profile of SCFA and free peptides, but two formulations fermented with Lactobacillus delbrueckii ssp. bulgaricus-151 and Lactobacillus casei-LcY were the most advantageous with desirable sensory, immunoreactive, and biochemical properties.

Differences in Regulatory Mechanisms Induced by ß-Lactoglobulin and κ-Casein in Cow's Milk Allergy Mouse Model-In Vivo and Ex Vivo Studies.

The presence of various proteins, including modified ones, in food which exhibit diverse immunogenic and sensitizing properties increases the difficulty of predicting host immune responses. Still, there is a lack of sufficiently reliable and comparable data and research models describing allergens in dietary matrices. The aim of the study was to estimate the immunomodulatory effects of ß-lactoglobulin (ß-lg) in comparison to those elicited by κ-casein (κ-CN), in vivo and ex vivo, using naïve splenocytes and a mouse sensitization model. Our results revealed that the humoral and cellular responses triggered by ß-lg and κ-CN were of diverse magnitudes and showed different dynamics in the induction of control mechanisms. ß-Lg turned out to be more immunogenic and induced a more dominant Th1 response than κ-CN, which triggered a significantly higher IgE response. For both proteins, CD4+ lymphocyte profiles correlated with CD4+CD25+ and CD4+CD25+Foxp3+ T cells induction and interleukin 10 secretion, but ß-lg induced more CD4+CD25+Foxp3- Tregs. Moreover, ex vivo studies showed the risk of interaction of immune responses to different milk proteins, which may exacerbate allergy, especially the one caused by ß-lg. In conclusion, the applied model of in vivo and ex vivo exposure to ß-lg and κ-CN showed significant differences in immunoreactivity of the tested proteins (κ-CN demonstrated stronger allergenic potential than ß-lg), and may be useful for the estimation of allergenic potential of various food proteins, including those modified in technological processes.

Two Faces of Milk Proteins Peptides with Both Allergenic and Multidimensional Health Beneficial Impact- Integrated In Vitro/In Silico Approach.

The main food-origin antigens that the infant's body is in contact with are cow's milk proteins (CMP). Still, CMP are one of the main sources of beneficial biologically active peptides that play a role in treatment of non-communicable diseases. Safe methods to quickly predict the sensitizing potential of food proteins among their range of health-promoting properties are essential. The aim of study was to adapt an integrated approach combining several in silico (IS) studies and in vitro (IV) assays to screen the multifunctionality of CMP-derived peptides. Major histocompatability complex type II MHC II-binders, interleukin-4 and -10 inducers, interferon γ -inducers and immunobioactivity tools were used to predict the peptide-power of inducing allergies or tolerance. A comparison of the peptide profiless revealed the presence of one identical and one overlapping sequence in IS and IV hydrolysate. By IS analysis, four of 24 peptides were found to have high affinity and stimulate IL-4 expression, and by IV, one of seven peptides had this potential (Bos d9 peptide DIPNPIGSENSEK (195-208)). Three IV peptides may induce IL-10 expression. The IV/IS assessment seems promising agents for peptides' potential determination dedicated only to preliminary screening of peptides. The IV verification is still crucial in further steps of studies.

Effect of Low-Immunogenic Yogurt Drinks and Probiotic Bacteria on Immunoreactivity of Cow's Milk Proteins and Tolerance Induction-In Vitro and In Vivo Studies.

There is no effective therapy for milk allergy. The role of lactic acid bacteria (LAB) and probiotics in protection against allergy-related outcomes is still under investigation. The aim of the study was to evaluate the immunomodulative and therapeutic potential of yogurt drinks in cow's milk allergy (CMA) management. We compared immunoreactivity of α-casein (α-CN), ß-casein (ß-CN), κ-casein (κ-CN), α-lactalbumin (α-LA), and ß-lactoglobulin (ß-LG) in 27 yogurt drinks fermented with different basic yogurt cultures, or yogurt cultures enriched with Lactobacillus plantarum and/or Bifidobacterium lactis strains, by competitive ELISA assay. Drinks with the lowest antigenic potential were used as allergoids for CMA therapy. BALB/c mice were sensitized via intraperitoneal injection of α-CN + ß-LG mixture with aluminum adjuvant, and gavaged with increasing doses of selected low-immunogenic drinks (YM-basic, or YM-LB-enriched with L. plantarum and B. lactis) to induce tolerance. Milk- or phosphate-buffered saline (PBS)-dosed mice served as controls. Compared to milk, the immunoreactivity of proteins in drinks increased or decreased, depending on the bacterial sets applied for fermentation. Only a few sets acted synergistically in reducing immunoreactivity. The selected low-immunogenic drinks stimulated allergic mice for profiling Th2 to Th1 response and acquire tolerance, and the effect was greater with YM-LB drink, which during long-lasting interventional feeding strongly increased the secretion of regulatory cytokines, i.e., IL-10 and TGF-ß, and IgA and decreased IL-4, IgE, and anti-(α-CN + ß-LG) IgG1. The studies revealed variations in the potency of yogurt bacteria to change allergenicity of milk proteins and the need for their strict selection to obtain a safe product for allergy sufferers. The YM-LB drink with reduced antigenic potential may be a source of allergoids used in the immunotherapy of IgE mediated CMA, but further clinical or volunteer studies are required.

Gestational Dysfunction-Driven Diets and Probiotic Supplementation Correlate with the Profile of Allergen-Specific Antibodies in the Serum of Allergy Sufferers.

BACKGROUND: Maternal diet has significant effects on development of childhood atopic disease and hypersensitivity development. However, the gestational dysfunctions demanding special diets are becoming a widespread phenomenon, their immunological implications can be manifested in the profile of antibodies in the offspring's serum. METHODS: 153 allergic and 150 healthy individuals were diagnosed for allergy using specific antibody and cytokine immunoassay tests. The medical history of subjects along with mothers' course of pregnancy was completed by allergologist's anamnesis. A self-organizing neural network and multivariate analyses to complex data and pick basic interactions were used. RESULTS: Two significant explanatory modules were determined. The first was formed by gestational diabetic and cholestatic diet, infant formula feeding type, probiotic supplementation and its BMI index, moderate IgE, increased IgG levels of antibodies and single or poly-food allergy type (7 clusters). The second was formed by gestational vegan/vegetarian and elimination diet, maternal probiotic supplementation, sex, high IgE total antibodies and food and mixed poly-allergy to aero- and food-origin allergens (19 clusters). CONCLUSIONS: Significant associations were observed between special gestational diet intake underlying foetal programming and the mechanisms of childhood allergy. The novelty is the positive association between diabetic and cholestatic diet intake and IgE/IgG-mediated food hypersensitivity.

Milk and Meat Allergens from Bos taurus ß-Lactoglobulin, α-Casein, and Bovine Serum Albumin: An In-Vivo Study of the Immune Response in Mice.

The mechanism of food allergy may vary. This study aimed to compare the effects of milk, yogurt, or beef meat supplementation on humoral and cellular immune responses in a mice model. Mice were divided into four groups: The "Milk group" was sensitized with a ß-lactoglobulin (ß-lg)/α-casein (α-CN) mixture and supplemented cow milk; the "Yogurt group" was sensitized with ß-lg/α-CN and supplemented yogurt; the "Beef group" was immunized with bovine serum albumin (BSA) and supplemented beef meat; and the "PBS group" received PBS in all procedures. ELISA was used to measure humoral response, including: Total IgE, specific IgG, and IgA. Cellular response was determined by phenotyping lymphocyte from lymphoid tissue and measuring the Th1/Th2 cytokine concentration with flow cytometry. The qPCR method was used for quantification of the fecal microbiota. The results obtained revealed a lower IgE level for the Yogurt group than for the Milk one. In the Yogurt group, the contribution of regulatory T cells to MLN and PP was higher compared to the other groups. We confirmed that diet supplementation with yogurt modulates the immune response to the prime allergen, and changes the activity of serum antibodies to milk proteins and BSA. Based on a specific antibodies level, we cannot exclude the possibility of CMA mice reaction against BSA.

Frequency of infections caused by ESBL-producing bacteria in a pediatric ward - single-center five-year observation.

INTRODUCTION: Infections caused by Enterobacteriaceae producing extended-spectrum ß-lactamases (ESBLs) are a serious therapeutic and clinical problem. An increasing role of ESBL(+) pathogens is observed in both community- and hospital-acquired infections. The aim of the study was to assess the incidence and the risk factors for ESBL(+) bacteria infection in a pediatric ward during a 5-year period. MATERIAL AND METHODS: The medical documentation data of patients hospitalized in the Department of Pediatrics, Pediatric Nephrology and Allergology between 2011 and 2015 were subjected to a retrospective analysis. Cases of ESBL(+) bacterial infections were analyzed in detail. RESULTS: 0.57% (46) of all the hospitalizations (8015) during the 5-year observation period in our department were caused by ESBL (+) pathogens. It constituted 8.5% of all positive microbiological cultures obtained. The analysis revealed an increasing trend in the number of ESBL (+) infections throughout the observed period. 43.5% of patients were only asymptomatic carriers. In 71.7% urinary tract structural and functional abnormalities were present. 76.1% of patients had been hospitalized previously and 60.9% had undergone urinary tract invasive procedures. CONCLUSIONS: The results confirm the rising trend of ESBL (+) infections during the observed period. ESBL (+) bacteria were isolated primarily in previously hospitalized children with particular reference to urinary tract invasive procedures during hospitalizations. Moreover, the study showed that patients with urogenital disorders and non-urinary chronic diseases are more susceptible to these priority pathogen infections.

Immunoreactive properties of α-casein and κ-casein: Ex vivo and in vivo studies.

The aim of this study was to evaluate the ex vivo and in vivo studies immune potential of α- and κ-casein. Ex vivo, naïve mouse splenocytes were stimulated with α- or κ-casein. After 120 h of culture, the proliferation index (PI), determined by 3-(4,5 dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and carboxyfluorescein diacetate N-succinimidyl ester (CFSE) staining, did not vary for either antigen, suggesting similar ex vivo immunogenic potential of both casein fractions. In vivo, BALB/ccmdb mice were sensitized with α- or κ-casein and then gavaged with primary antigen. Mice immunized with α-casein had higher levels of IgG (216.33) and IgA (210.22) in serum at the end of the experiment compared with mice immunized with κ-casein (215 and 29.3 for IgG and IgA, respectively). The use of α-casein for mouse immunization and ex vivo lymphocyte stimulation resulted in higher concentrations of secreted cytokines (IL-4, IL-10) compared with κ-casein stimulation. This is consistent with increasing regulatory T cell (Treg) lymphocyte populations, independent of the antigen used for stimulation. In summary, the immunogenic potential of α- and κ-casein was similar. Humoral and cellular immune responses confirmed their strong, independent potential to induce B and T cells. We propose that the lymphocyte proliferation index be used as an initial screening for protein immunogenicity.