BackgroundIn Crohn’s disease (CD), the involvement of food antigens in immune responses remains unclear. The objective of this study was to detect immune responses against food antigens in CD patients and examine the mechanism in a mouse model of colitis.MethodsWe enrolled 98 CD patients, 50 ulcerative colitis patients, and 52 healthy controls (HCs) to compare the levels of serum immunoglobulin (Ig)Gs against 88 foods. The presence of serum IgGs against foods was also examined in interleukin (IL)-10 knockout (KO) mice in which CD4+ T cell activation by antigenic food protein was assessed. Mice transferred with IL-10 KO cells received diets with or without food antigens, and the development of colitis was evaluated.ResultsThe prevalence of IgGs against various foods, especially vegetables, grains, and nuts, was significantly higher in CD patients than in HCs. Similarly, the prevalence of IgGs against food proteins was higher in IL-10 KO mice than in BALB/c mice. Beta-conglycinin, identified as an antigenic food proteins in IL-10 KO mice, induced CD4+ T cell production of interferon-γ and IL-17 through dendritic cell antigen presentation. Elimination of the food antigens ameliorated the development of colitis in mice without altering the composition of their intestinal microbiota.ConclusionsIn CD colitis mice, intestinal inflammation via CD4+ T cell hyperactivation was induced by food antigens associated with high serum IgG levels and was ameliorated by the elimination of food antigens. This disrupted immunological tolerance to food antigen, which might act as an exacerbating factor, remains to be elucidated in CD patients.Electronic supplementary materialThe online version of this article (doi:10.1007/s00535-014-0981-8) contains supplementary material, which is available to authorized users.
ED alleviated adverse reactions to 5-FU without affecting antitumor activity. Protection against 5-FU-induced weight loss was potentially due to both improved nutritional support with combined ingredients and prevention of diarrhea that is associated with reduced colonic goblet cells and decreased saliva production from reduced salivary gland contraction.
Benzaldehyde is an organic compound with an almond-like aroma and one of the most important and widely used flavorings in the food industry. To develop an enzymatic process for the production of benzaldehyde from l-phenylalanine, four enzymes were expressed in Escherichia coli; l-amino acid deaminase, 4-hydroxymandelate synthase, (S)-mandelate dehydrogenase, and benzoylformate decarboxylase. Although each E. coli strain could be used to synthesize benzaldehyde from l-phenylalanine, the yield was low due to accumulation of an intermediate, phenylpyruvic acid. We developed a second reaction step by engineering 4-hydroxymandelate synthase of Actinoplanes teichomyceticus. A quadruple mutant of 4-hydroxymandelate synthase (A199V/Q206R/I217V/K337Q) obtained by random and site-directed mutagenesis demonstrated 2.4-fold higher activity than wild type. Furthermore, the mutant-expressing strain was able to produce benzaldehyde from 100 mM l-phenylalanine at a conversion rate of 84% (wild type, 37%). We report the development of an efficient process for benzaldehyde production using l-phenylalanine as a substrate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.