Antigen-induced immune suppression, like T cell activation, requires antigen-presenting cells (APCs); however, the role of APCs in mediating these opposing effects is not well understood, especially in vivo. We report that genetic inactivation of CD11b, which is a CD18 subfamily of integrin receptors that is highly expressed on APCs, abolishes orally induced peripheral immune tolerance (oral to...

BACKGROUND Peripheral blood CD8+ T cells expressing interferon gamma and interleukin-4 (IL-4), and lacking CD28 molecules, were responsible for the dynamic interplay between peripheral blood and inflammatory sites. INTRODUCTION The aim of the current study was to define in Behçet's disease (BD), CD8+ T-cell subsets using CD28 and CD11b monoclonal antibodies, and the characterization of the Tc...

In vitro incubation of mouse blood eosinophils with dexamethasone (DEX) resulted in concentration- and time-dependent reduction in CD11b and CD49d cell-surface expression as detected by flow cytometry. This inhibitory effect ranged between 20 and 40% for both integrins, and it was not related to alteration of cell survival. DEX was maximally effective at 1 microM, and it was prevented by coaddi...

T cells recovering after bone marrow transplantation (BMT) were analyzed for their phenotypic and functional features by two-color immunofluorescence and a high efficiency cloning technique. A predominance of cells co-expressing natural killer (NK)-related surface antigens, such as Leu 7 (CD57) and CD11b, was detected within both the CD4+ and CD8+ subsets from 5 months postgrafting onward. Such...

Japanese encephalitis (JE) is neuroinflammation characterized by uncontrolled infiltration of peripheral leukocytes into the central nervous system (CNS). We previously demonstrated exacerbation of JE following CD11chi dendritic cell (DC) ablation in CD11c-DTR transgenic mice. Moreover, CD11chi DC ablation led to abnormal differentiation of CD11b+Ly-6Chi monocytes and enhanced permeability of t...

We previously reported that Mycobacterium tuberculosis triggers macrophage necrosis in vitro at a threshold intracellular load of ~25 bacilli. This suggests a model for tuberculosis where bacilli invading lung macrophages at low multiplicity of infection proliferate to burst size and spread to naïve phagocytes for repeated cycles of replication and cytolysis. The current study evaluated that mo...

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects several million people in Latin America. Myocarditis, observed in the acute and chronic phases of the disease, is characterized by a mononuclear cell inflammatory infiltrate. We previously identified a myeloid cell population in the inflammatory heart infiltrate of infected mice that expressed arginase I. In this study,...

1 Incubation of human eosinophils in BSA-coated tissue culture plates resulted in time-dependent adhesion and attendant activation of the NADPH oxidase that were both inhibited (by >85%) by blocking antibodies raised against CD11b and CD18. 2 SB 203580, an inhibitor of p38 mitogen-activated protein (MAP) kinase, did not influence adhesion but inhibited superoxide anion generation (pIC50=-6.57)....

OBJECTIVE Mice with CCR2 deficiency are protected from insulin resistance but only after long periods of high-fat diet (HFD) feeding, despite the virtual absence of circulating inflammatory monocytes. We performed a time course study in mice with hematopoietic and global CCR2 deficiency to determine adipose tissue-specific mechanisms for the delayed impact of CCR2 deficiency on insulin resistan...

The goal of the innate immune system is containment of a pathogen at the site of infection prior to the initiation of an effective adaptive immune response. However, effector mechanisms must be kept in check to combat the pathogen while simultaneously limiting undesirable destruction of tissue resulting from these actions. Here we demonstrate that innate immune effector cells contain a peripher...