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Summary: Natural immunoglobulin M (IgM) is reactive to autoantigens and is believed to be important for autoimmunity. Blood pentameric IgM loaded with antigens forms a large immune complex (IC) that contains various elements, including apoptosis inhibitor of macrophage (AIM). Here we demonstrate that this IgM-AIM association contributes to autoantibody production under obese conditions. In mice fed a high-fat diet, natural IgM increased through B cell TLR4 stimulation. AIM associated with IgM and protected AIM from renal excretion, increasing blood AIM levels along with the obesity-induced IgM augmentation. Meanwhile, the AIM association inhibited IgM binding to the Fcα/μ receptor on splenic follicular dendritic cells, thereby protecting the IgM IC from Fcα/μ receptor-mediated internalization. This supported IgM-dependent autoantigen presentation to B cells, stimulating IgG autoantibody production. Accordingly, in obese AIM-deficient (AIM −/− ) mice, the increase of multiple IgG autoantibodies observed in obese wild-type mice was abrogated. Thus, the AIM-IgM association plays a critical role in the obesity-associated autoimmune process. [Copyright &y& Elsevier]

Background Recent studies have suggested that epidermal barrier dysfunction contributes to the development of atopic dermatitis (AD) and other allergic diseases. Objective We performed a prospective, randomized controlled trial to investigate whether protecting the skin barrier with a moisturizer during the neonatal period prevents development of AD and allergic sensitization. Methods An emulsion-type moisturizer was applied daily during the first 32 weeks of life to 59 of 118 neonates at high risk for AD (based on having a parent or sibling with AD) who were enrolled in this study. The onset of AD (eczematous symptoms lasting >4 weeks) and eczema (lasting >2 weeks) was assessed by a dermatology specialist on the basis of the modified Hanifin and Rajka criteria. The primary outcome was the cumulative incidence of AD plus eczema (AD/eczema) at week 32 of life. A secondary outcome, allergic sensitization, was evaluated based on serum levels of allergen-specific IgE determined by using a high-sensitivity allergen microarray of diamond-like carbon–coated chips. Results Approximately 32% fewer neonates who received the moisturizer had AD/eczema by week 32 than control subjects ( P = .012, log-rank test). We did not show a statistically significant effect of emollient on allergic sensitization based on the level of IgE antibody against egg white at 0.34 kU A /L CAP-FEIA equivalents. However, the sensitization rate was significantly higher in infants who had AD/eczema than in those who did not (odds ratio, 2.86; 95% CI, 1.22-6.73). Conclusion Daily application of moisturizer during the first 32 weeks of life reduces the risk of AD/eczema in infants. Allergic sensitization during this time period is associated with the presence of eczematous skin but not with moisturizer use. [ABSTRACT FROM AUTHOR]

Objectives We assessed the vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) in children 6 months to 15 years of age during the 2016/17 season. In addition, we estimated the impact of repeated vaccination in children on VE. Methods Our study for VEs in preventing influenza and admission due to influenza were conducted according to a test-negative case-control design (TNCC) based on influenza rapid diagnostic test results. We also analyzed the VE by vaccine status in the current and previous seasons for the impact of repeated vaccination. Results During the 2016/17 season, the quadrivalent IIV was used in Japan. The adjusted VE in preventing influenza illness was 38% (95% CI, 29–46) against influenza A and 39% (95% CI, 18–54) against influenza B. Infants showed no significant VE. The VE in preventing hospitalization was not demonstrated. For the analysis of repeated vaccination, the vaccine was effective only when immunization occurred in the current season. The children who were immunized in two consecutive seasons were more likely to develop influenza compared to those immunized in the current season only (odds ratio, 1.58 [95% CI, 1.05–2.38], adjusted odds ratio, 1.53 [95% CI, 0.99–2.35]). However, the odds ratio of repeated vaccination was not significant when the analysis excluded those who developed influenza in the previous season. Conclusions VE in children in the 2016/17 season was similar to values previously reported. Repeated vaccination interfered with the VE against any influenza infection in the 2016/17 season. The results of our study suggest that decreased VE by repeat vaccination phenomenon was associated with immunity by influenza infection in the previous season. However, the influenza vaccine should be recommended every season for children. [ABSTRACT FROM AUTHOR]