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Background Chronic inflammation and insulin resistance are factors that are related to obesity. We have suggested that the administration of heat-treated Lactobacillus plantarum OLL2712 (OLL2712) cells can improve glucose and lipid metabolism by suppressing chronic inflammation in mouse models and a preliminary clinical study. Objective The aim of this study was to investigate whether ingesting OLL2712 cells can reduce body fat accumulation and improve metabolic risk factors, in overweight, healthy adults. Methods This study was a randomized, double-blind, placebo-controlled, parallel-group trial conducted at a single center in Japan. The study participants included 100 overweight (BMI range, ≥25 to <30 kg/m2) adults aged 20–64 y. They were randomly assigned to either the placebo or OLL2712 group (n  = 50 each) and were administered conventional yogurt or yogurt containing >5 × 109 heat-treated OLL2712 cells, respectively, daily for 12 wk. The primary outcome was the 12-wk change in the abdominal fat area, as assessed by computed tomography, and the secondary outcomes were glucose and lipid metabolism-related parameters and chronic inflammation markers, which were analyzed using a linear mixed model. Results The 12-wk change of abdominal fat area (difference: 8.5 cm2; 95% CI: 0.3, 16.6 cm2; P  = 0.040) and fasting plasma glucose (difference: 3.2 mg/dL; 95% CI: 0.8, 5.6 mg/dL; P  = 0.021) were significantly less in the OLL2712 group than the placebo group. The overall trend of serum IL-6 was significantly decreased in the OLL2712 group compared with baseline and the placebo group. Conclusions The ingestion of heat-treated OLL2712 cells reduces body fat accumulation and the deterioration of glycemic control and chronic inflammation, in overweight, healthy adults. We hypothesize that OLL2712 cells may prevent obesity by regulating chronic inflammation. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry as UMIN000027709. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that various food components affect the immune response. These components act on various immune cells, and their effects are mediated through the intestinal immune system and, in some cases, the intestinal microbiota. In this review, we describe the immunomodulating effects of various food components, including probiotics, prebiotics, polysaccharides, vitamins, minerals, fatty acids, peptides, amino acids and polyphenols. Some of these components enhance immune responses, leading to host defense against infection, whereas others inhibit immune responses, thus suppressing allergy and inflammation. [ABSTRACT FROM AUTHOR]

In human trials, Bifidobacterium longum BB536 alleviates subjective symptoms of Japanese cedar pollinosis, an IgE-mediated type I allergy caused by exposure to Japanese cedar, and significantly suppresses the increase of plasma thymus- and activation-regulated chemokine (TARC) associated with pollen dispersion. In the present study, we investigated the suppressive effects of BB536 on the production of T helper type 2 (Th2)-attracting chemokines, such as TARC and macrophage-derived chemokine (MDC), together with the mechanisms of their production. Murine splenocytes were cultured with heat-killed BB536, and the levels of Th2-attracting chemokines in the supernatants were measured. TARC and MDC were produced in cultures without stimulation, and the production was significantly suppressed by BB536. These chemokines were produced by antigen-presenting cells (APCs) of splenocytes stimulated with an anti-CD40 antibody. Furthermore, TARC production was induced with granulocyte macrophage colony-stimulating factor that was produced by T cells and dendritic cells. BB536 suppressed MDC production induced with the anti-CD40 antibody by APCs from the spleen, mesenteric lymph nodes (MLNs) and Peyer's patches, and it suppressed TARC production by APCs from the spleen and MLNs. These results indicate that BB536 suppresses the production of Th2-attracting chemokines induced by the T cell–APC interaction, suggesting a novel mechanism for alleviating symptoms of allergic disorders by probiotics. [ABSTRACT FROM AUTHOR]

The article presents a study which compares the immunomodulatory effects of Bacteroides and Lactobacillus on Immunoglobulin A (IgA) production by Peyer's patches lymphocytes. It notes that the Bacteroides have stronger ability to induce Peyer's patches lymphocyte IgA production than Lactobacillus. Moreover, it also states that murine intestinal commensal bacteria stimulates mucosal IgA production.

The article discusses a study which examines the effect of dietary melibiose (6-o-α-D-galactopyranosyl-D-glucose) on T-helper (Th) cell responses induced by an orally fed antigen in ovalbumin-specific T cell receptor transgenic mice. Dietary melibiose significantly decreased the Th2 type responses, shown by a significant decrease in the interleukin-4 production and T cell proliferative response induced by sensitization from the oral administration of ovalbumin.

Describes a polymerase chain reaction method for the detection of buckwheat DNA using primers corresponding to internal transcribed spacer region. Information on the presence of buckwheat contamination in food; Causes of allergies; Risk of raising the buckwheat allergy due to allergens derived from wild buckwheat.

T cell responses directed toward TCR‐derived peptides have been shown to be an important regulatory mechanism of protection against autoimmunity. Here, we show that a naturally induced TCR‐directed immune response can delay the onset of collagen‐induced arthritis (CIA), an animal model of autoimmune rheumatoid arthritis in humans. DBA/1 mice were pretreated with an immunodominant peptide, p245–270, from bovine type II collagen (bCII) and were subsequently immunized with whole bCII for the induction of arthritis. The results showed that preactivation of p245–270‐reactive cells delayed the onset and reduced the severity of CIA, compared with animals in the control group. Interestingly, the serum antibody response to bCII and the bCII‐specific cytokine were not affected under these conditions. This result indicates that the observed protection was neither directly due to a lower antibody response nor due to the immune deviation of the anti‐bCII T cell response. Furthermore, immunization with p245–270, but not bCII, induced a strong response to the B5 peptide, an immunodominant region of the TCR Vβ8.2 (amino acids 76–101) that binds very strongly to I‐Aq. These data suggest that at a critical phase in the loss of self‐tolerance, an effective anti‐TCR response, induced naturally, can regulate the pathogenic autoimmune response and thus may provide protection against autoimmunity. [ABSTRACT FROM PUBLISHER]

Reports on a study which reveals that antigen feeding increases frequency and antigen-specific proliferation ability of intraepithelial CD4[sup +] T cells in alphabeta T cell receptor transgenic mice. Changes in the population of IEL in response to orally administered Ag; Changes in Ag-specific reactivity of IEL in response to orally administered Ag; Proliferative response of CD4[sup +] and CD4[sup -] IEL sorted by MACS.

The recirculation of lymphocytes through the intestinal mucosa is important for specific immune defense, but the origin and differentiation of intraepithelial lymphocytes (IEL) are not fully understood. The present study therefore used intravital microscopy to investigate the migration of IEL to the villus mucosa and Peyer's patches of the small intestine. IEL were separated from inverted murine small intestine and mesenteric lymph node (MLN) T cells were also isolated. The adhesion of fluorescence-labeled lymphocytes to postcapillary venules (PCV) of Peyer's patches and arcade microvessels of small intestinal villi was observed after injection. In some experiments, the effect of antibodies against adhesion molecules on cell kinetics were investigated. IEL time-dependently accumulated in villus microvessels of the small intestine, whereas few MLN cells did. Few IEL adhered to the PCV of Peyer's patches. IEL were shown to express αEβ7-integrin but not L-selectin. The accumulation of IEL in villus archade was significantly inhibited by antibody against β7-integrin or mucosal addressin cell adhesion molecules (MAdCAM)-1, but not by αE-integrin. The combined blocking of β7-integrin and MAdCAM-1 further attenuated the sticking of IEL in this area, although it did not entirely block the IEL adherence. The adherence of CD4+ or TCRαβ IEL to villus microvessels was significantly greater than that of CD4− or TCRγδ IEL. It was demonstrated in situ for the first time that IEL adhered selectively to the villus microvessels of the small intestine partly via β7 and MAdCAM-1. [ABSTRACT FROM PUBLISHER]

Immunological tolerance of systemic immunity can be induced by the oral administration of an exogenous antigen, which is termed oral tolerance. We examined whether there was a difference in the degree of tolerance between individual antigenic determinants in oral tolerance. Feeding bovine αs1-casein, a major protein in cow's milk, as a constituent of the diet induces oral tolerance in mice. However, a weak antibody response can be elicited in the αs1-casein-fed animals by subsequent immunization with the antigen. We examined the fine specificity of such anti-αs1-casein antibodies produced in αs1-casein-fed mice. The results demonstrated that there was a difference in the inhibition of antibody response between different B cell determinants. Differential inhibition could also be observed for T cell responses. T cells specific for dominant determinants were preferentially tolerized, while those for cryptic determinants escaped oral tolerance. Our results imply the importance of antigen presentation for this differential inhibition of antigenic determinants. We suggest that orally administered antigen does not induce tolerance to some of the B and T lymphocyte repertoire which could potentially induce harmful food hypersensitivity. [ABSTRACT FROM PUBLISHER]

The article focuses on a research concerning the analysis of two different epitopes including OVA23-3 CD4+T cells and DO11.10 CD4+T cells in the ovalbumin 323-339 (OVA 323-339) peptide of mice or food allergic patients. The research found that OVA23-3 CD4+T identified the Th2-phenotype while DO11.10 CD4+T cells identified the Th1-phenotype. It also discusses the impact of these differences on the immune responses of mice.