Humans are continuously exposed to a high number of diverse pathogens that induce different types of immune responses. Primary pathogen-specific immune responses generate multiple subsets of memory T cells, which provide protection against secondary infections. In recent years, several novel T cell subsets have been identified and have significantly broadened our knowledge about T cell differentiation and the regulation of immune responses. At the same time the rapidly growing number of incompletely characterized T cell subsets has also generated some controversies. We therefore review here the current knowledge on features and functions of human α/β T cell subsets, focusing on CD4+ T cells classified according to cytokine production and tissue localization. The principal helper and regulatory T cell subsets can be identified by a limited number of relevant surface markers, which are an integral part of the T cell differentiation programs because they are directly induced by the relevant lineage-defining transcription factors. In vivo occurring human T cell subsets can thus be purified directly ex vivo from relevant tissues for molecular and functional studies, and represent not only an ideal model to study T cell differentiation, but they also offer important clinical opportunities. © 2013 Elsevier Ltd.
|Titolo:||The CD4-centered universe of human T cell subsets|
|Parole Chiave:||CD4+ memory T cells; Cytokines; T cell differentiation; Tissue homing|
|Settore Scientifico Disciplinare:||Settore MED/12 - Gastroenterologia|
|Data di pubblicazione:||nov-2013|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.smim.2013.10.012|
|Appare nelle tipologie:||01 - Articolo su periodico|