Objective. To investigate whether MHC class II expression on myeloid cells of patients with treatment-naive early rheumatoid arthritis (RA) correlates with disease progression. Methods. Monocytes were isolated by negative selection from the peripheral blood of 15 patients with early RA (disease duration 12 months), differentiated to macrophages and analysed for MHC class II expression by flowcy...

Human Vγ9δ2 (Vδ2) T cells represent a unique effector T cell population in humans and primates detecting nonpeptid phosphoantigens, playing an important role in antimicrobial and antitumor immunity. Currently, it is believed that various leukocyte subsets can promote phosphoantigen-driven Vδ2 cell expansion, but the essential cell type required remains elusive. We have used high purity cell sor...

Bone marrow-derived mast cells as well as dendritic cells, macrophages and B lymphocytes express major histocompatibility complex (MHC) class II molecules. In mast cells, the majority of MHC class II molecules reside in intracellular cell type-specific compartments, secretory granules. To understand the molecular basis for the localisation of MHC class II molecules in secretory granules, MHC cl...

Regulation of MHC class II gene expression is an essential aspect of the control of the immune response. Primary MHC class II deficiency is a genetically heterogeneous disease of gene regulation that offers the unique opportunity of a genetic approach for the identification of the functionally relevant regulatory genes and factors. Most patients exhibit a characteristic defect in the binding of...

The antigen-presenting abilities of basophils and their role in initiating a Th2 phenotype is a topic of current controversy. We aimed to determine whether human basophils can be induced to express MHC Class II and act as antigen presenting cells for T cell stimulation. Isolated human basophils were exposed to a panel of cytokines and TLR-ligands and assessed for MHC Class II expression. MHC Cl...

OBJECTIVE To investigate whether MHC class II expression on myeloid cells of patients with treatment-naive early rheumatoid arthritis (RA) correlates with disease progression. METHODS Monocytes were isolated by negative selection from the peripheral blood of 15 patients with early RA (disease duration < or =12 months), differentiated to macrophages and analysed for MHC class II expression by ...

Tumor-associated macrophages (TAM) are exposed to multiple microenvironmental cues in tumors, which collaborate to endow these cells with protumoral activities. Hypoxia, caused by an imbalance in oxygen supply and demand because of a poorly organized vasculature, is often a prominent feature in solid tumors. However, to what extent tumor hypoxia regulates the TAM phenotype in vivo is unknown. H...

We investigated the role of B cell Ag presentation in homeostasis of the memory B cell compartment in a mouse model where a conditional allele for the beta-chain of MHC class II (MHC-II) is deleted in the vast majority of all B cells by cd19 promoter-mediated expression of Cre recombinase (IA-B mice). Upon T cell-dependent immunization, a small number of MHC-II(+) B cells in IA-B mice dramatica...

The currently accepted model for superantigen (SAg) induced T cell activation suggests that SAg, without being processed, cross link both MHC class II, from Antigen Presenting Cells (APC), and V-, from T-cell receptor (TCR), initiating nonspecific T-cell activation. This T-cell proliferation induces a massive cytokine release associated with several human diseases. It is thought that murine CD...

Helicobacter pylori infection is associated with gastric epithelial damage, including apoptosis, ulceration, and cancer. Although bacterial factors and the host response are believed to contribute to gastric disease, no receptor has been identified that explains how the bacteria attach and signal the host cell to undergo apoptosis. Using H. pylori as "bait" to capture receptor proteins in solub...