Reviews & Analysis

A new subset of interleukin 17–producing CD4⁺ helper T cells with diverse functions has now been identified. New work by three groups substantially broadens the understanding of these cells in both mice and humans.

Studies of genetically modified reporter mice have provided insight into the development of regulatory T cells. New work shows that regulatory T cells producing interleukin 10 arise in the periphery from Foxp3⁺ and Foxp3⁻ thymic progenitors.

A new study in Nature identifies a long-sought cytoplasmic 'sensor' that is responsible, at least in part, for interferon responses induced by double-stranded DNA.

Specialized macrophage-like cells initiate antibody responses by trapping antigen in lymph. These antigen-trapping cells are located in the migration pathway of recirculating B cells, which can engage the trapped antigen.

A June 2007 meeting of immunologists in Crete focused on the intricate interconnections between the innate and adaptive immune systems and their implications for host defense against pathogens.

Transcription factor GATA-3 is essential for T lineage development. New data suggest that GATA-3 also can have a determining function in mast cell lineage development.

The regulation of T cell survival and apoptosis contributes to the pathogenesis of autoimmune disease. A new study shows that the transcriptional regulator β-arrestin 1 enhances antiapoptotic Bcl-2 in T cells, which can heighten autoimmune disease.

Tapasin enhances the loading and editing of peptide 'cargo' onto major histocompatibility complex class I molecules, yet it cannot do so alone. Two new reports show that the oxidoreductase ERp57 assists tapasin in these activities.

Time- and tissue-specific recombination of antigen-receptor genes is regulated in part by locus accessibility. New evidence demonstrates a specific function for nucleosome remodeling in the T cell receptor-β locus to allow recombination in thymocytes.

At the first meeting of the new three-part EMBO Conference series on “Signaling in the immune system,” immunologists presented key findings and highlighted new questions and emerging trends.

Toll-like receptors respond to ligands embedded in pathogen-derived macromolecules to induce immune responses. Binding of a stimulatory ligand to preexisting dimers of Toll-like receptor 9 induces conformational changes that lead to their full activation.

Allelic exclusion acts to ensure lymphocytes express only one antigen receptor on their surfaces. Differences in DNA methylation are now shown to distinguish alleles for subsequent somatic hypermutation steps leading to antibody affinity maturation.

Intensive characterization of the locus encoding interferon-γ provides new insight into how proper gene expression is achieved in polarizing T cells. NOTE: In the version of this News & Views initially published, the figure credit is missing. This figure should be credited to Ann Thomson. The error has been corrected in the HTML and PDF versions of the article.