IL-21 Regulates the Differentiation of a Human γδ T Cell Subset Equipped with B Cell Helper Activity Caccamo, Nadia ; Todaro, Matilde ; La Manna, Marco P. ; Sireci, Guido ; Stassi, Giorgio ; Dieli, Francesco Abstract Publication: PLoS ONE Pub Date: July 2012 DOI: 10.1371/journal.pone.0041940 Bibcode: 2012PLoSO...741940C