B1 cells are evolutionarily conserved innate-like cells that share many features with macrophages. It has also been established that B1 cells have a close developmental relationship with macrophages. However, whether B1 cells are able to act as professional phagocytic cells is not clear. In this study, we report that mouse peritoneal cavity (PerC) B cells demonstrate in vivo and in vitro phagocytic activities for Staphylococcus aureus, Escherichia coli, and polystyrene fluorescent microspheres. Approximately 5% of PerC B cells, mainly B1b cells, showed phagocytic activity. Ingested microbes were killed efficiently in the phagolysosome. The antigen-specific B-cell antigen receptor promoted B-cell phagocytosis, resulting in antigen presentation to T cells after uptake of bacteria. Our results reveal for the first time that mouse B1 cells have active phagocytic capabilities and thereby act as a bridge linking innate and adaptive immunity.

BackgroundDiabetes has become a major public health problem in China. Support of patient self-management is a key component of effective diabetes care and improved patient outcomes. A series of peer-led community-based disease-specific self-management programs including diabetes have been widely disseminated in urban communities of Shanghai since 1999. However, the strategy of using trained lay leaders to support patient self-management faces challenges in rural communities in Shanghai. This study developed a Chinese diabetes group visit program as an alternative approach to support patient self-management and examined its effectiveness on self-management behaviors, self-efficacy and health status for patients with type 2 diabetes in rural communities of Shanghai.Methods208 patients with type 2 diabetes aged 35–80 years were randomly assigned to the intervention group (n=119) of 12 monthly group visit sessions or to a control group (n=89) of usual care. The trial was undertaken in two rural communities in Shanghai, China. Randomization and allocation to study group were carried out by using a random number table. Analysis of covariance was used to compare changes in the 17 self-management behavior, self-efficacy and health status related variables in two groups at 12 months’ follow-up based on 176 patients (n=98; n=78).ResultsCompared with controls, the intervention patients, on average, increased their duration of aerobic exercise by more than 40 minutes per week (p=0.001); had significant increase of 0.71 in mean score on self-efficacy to manage diabetes (p=0.02); and had significant improvements in measures of illness intrusiveness and systolic blood pressure. The intervention patients attended an average of 10.1 of the 12 program sessions with 75.6% of them attended 10 and more sessions.ConclusionThe Chinese diabetes group visit model is a feasible, acceptable and effective alternative for supporting diabetes patient self-management in Chinese rural communities. The model requires larger studies to determine its effect on blood glucose control and health care utilization.Trial registrationISRCTN87909028

Hepatitis C virus (HCV) is an important cause of chronic liver disease worldwide. Development of vaccines to prevent HCV infection, or at least prevent progression to chronicity, is a major goal. In mice and rhesus macaques, a DNA vaccine encoding cell-surface HCV-envelope 2 (E2) glycoprotein stimulated stronger immune responses than a vaccine encoding intracellular E2. Therefore, we used DNA encoding surface-expressed E2 to immunize chimpanzees 2768 and 3001. Chimpanzee 3001 developed anti-E2 after the second immunization and antibodies to hypervariable region 1 (HVR1) after the third immunization. Although chimpanzee 2768 had only low levels of anti-E2 after the third immunization, an anamnestic response occurred after HCV challenge. CTL responses to E2 were not detected before challenge, but a strong response was detected after HCV challenge in chimpanzee 2768. An E2-specific CD4؉ response was detected in chimpanzee 2768 before challenge and in both chimpanzees postchallenge. Three weeks after the last immunization, animals were challenged with 100 50% chimpanzee-infectious doses (CID 50 ) of homologous monoclonal HCV. As a control, a naive chimpanzee was inoculated with 3 CID 50 of the challenge virus. The vaccine did not generate sterilizing immunity because both vaccinated chimpanzees were infected. However, both vaccinated chimpanzees resolved the infection early whereas the control animal became chronically infected. Compared with the control animal, hepatitis appeared earlier in the course of the infection in both vaccinated chimpanzees. Therefore, DNA vaccine encoding cell surface-expressed E2 did not elicit sterilizing immunity in chimpanzees against challenge with a monoclonal homologous virus, but did appear to modify the infection and might have prevented progression to chronicity. (HEPATOLOGY 2000;32:618-625.)Hepatitis C virus (HCV) is a major cause of chronic liver disease worldwide. 1 More than 2% of the entire world population is chronically infected with this virus; liver cirrhosis and hepatocellular carcinoma are recognized long-term sequelae of chronic HCV infection. 1 Chronic HCV infection has been treated with interferon but less than 20% of patients achieve a sustained response with this drug. 2 Combination therapy of interferon and the nucleoside analog ribavirin has increased the rate of sustained response to more than 30%, [3][4][5] and it is expected that in the next few years, new antiviral agents will further improve the response rate in chronically infected patients. The combination of more effective antiviral drugs and the lower incidence of new HCV infections since the introduction of anti-HCV screening of blood products will eventually reduce the prevalence of HCV infection in industrialized countries. However, HCV still causes at least 30,000 new cases of hepatitis in the United States each year. 6 In developing countries, where the prevalence of HCV infection in the general population can be as high as 30%, 7 strategies to prevent HCV transmission are not universally implement...

Background:The typical two-cysteine peroxiredoxin Ahp1 catalyzes the decomposition of alkyl hydroperoxides. Results: Ahp1 possesses a peroxidatic Cys-62 after resolving Cys-31 and an A-type dimer interface that contributes to the positive cooperativity of hydroperoxide binding. Conclusion: Ahp1 defines a novel group of thioredoxin-dependent peroxidases. Significance: Provided is the first structural snapshot of electron transfer from thioredoxin to a thioredoxin-like protein.