This work was supported by grants from the European Community to TL; Network of Excellence Europrise (LSHP-CT-2006-037611) and MUVAPRED (LSHP-CT-2003-503558). The authors declare that there is no conflict of interest. “
“Understanding how the immune response is activated and amplified requires detailed knowledge of the stages in the formation of the immunological synapse (IS) between T lymphocytes and antigen-presenting cells (APCs). We show that tetraspanins CD9 and CD151 congregate at the T-cell side of the IS. Silencing of CD9 or CD151 blunts the IL-2 secretion and expression of the activation marker CD69 by APC-conjugated

T lymphocytes, but does not affect the accumulation of CD3 or actin to the IS, or the translocation of the microtubule-organizing center toward the T-B contact area. CD9 or CD151 silencing diminishes the relocalization selleck of α4β1 integrin click here to the IS and reduces the accumulation of high-affinity β1 integrins at the cell–cell contact. These changes are accompanied by diminished phosphorylation of the integrin downstream targets FAK and

ERK1/2. Our results suggest that CD9 and CD151 support integrin-mediated signaling at the IS. “
“The Jenner Institute (ORCRB), Nuffield Department of Medicine, University of Oxford, Oxford The frequency of CD4+Foxp3+ regulatory T cells (Tregs) is often significantly increased in the blood of tumour-bearing mice and people with cancer. Moreover, Treg frequencies are often higher in tumours compared to blood and lymphoid organs. We wished to determine

whether certain chemokines expressed within the tumour mass selectively recruit Tregs, thereby contributing to their enrichment within the tumour-infiltrating lymphocyte pool. To achieve this goal, the chemokine profile ADAMTS5 of carcinogen-induced fibrosarcomas was determined, and the chemokine receptor expression profiles of both CD4+Foxp3- and CD4+Foxp3+ T cells were compared. These analyses revealed that the tumours are characterised by expression of inflammatory chemokines (CCL2, CCL5, CCL7, CCL8, CCL12, CXCL9, CXCL10 and CX3CL1), reflected by an enrichment of activated Foxp3- and Foxp3+ T cells expressing Th1-associated chemokine receptors. Notably, we found that CXCR3+ T cells were significantly enriched in the tumours although curiously we found no evidence that CXCR3 was required for their recruitment. Instead, CXCR3 marks a population of activated Foxp3- and Foxp3+ T cells, which use multiple and overlapping ligand receptor pairs to guide their migration to tumours. Collectively, these data indicate that enrichment of Foxp3+ cells in tumours characterised by expression of inflammatory chemokines, does not occur via a distinct chemokine axis thus selective chemokine blockade is unlikely to represent a meaningful therapeutic strategy for preventing Treg accumulation in tumours. This article is protected by copyright. All rights reserved. “
“The first draft of the human malaria parasite’s genome was released in 2002.