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The HIV-AIDS epidemic in Africa is now of epic proportions. This has precipitated a crisis in public health that needs to be resolved in a uniquely African way. Local and Western research efforts must be blended with strong political and social will to get the preventative message and appropriate therapies to the people whom need them most.
Antigen receptor editing is no longer the province of B cells alone. T cells also can be caught in the act, given the right system. The T cell receptors of double positive thymocytes that recognize self antigens on the cortical epithelium with dangerously high affinity will undergo editing until they get it right.
Ever since it was proposed that distinct subsets of dendritic cells induce distinct subsets of T cells, immunologists have been struggling to reconcile those conclusions with other data. New experiments now illuminate a different interpretation.
Activation of Ras is key for lymphocyte development and function. The understanding of Ras activation in T cells now takes an important step forward by the initial analysis of mice lacking the Ras activator RasGRP.
How do T cells recognize allogeneic MHC molecules with such ferocity? The first crystal structure of an allo-MHC complexed with peptide and T cell receptor begins to reveal the answer.
The NF-κB family of transcription factors are central to signaling from Toll family receptors. The IKKγ protein of Drosophila has been found to regulate NF-κB family–member Relish, but not the similar protein DIF, in the fly innate immune response.
