Muriel Stubbe, MD-PhD student in the group of Arnaud Marchant, recently completed a study dissecting the responses of T lymphocytes elicited by the hepatitis B vaccine in humans. This work, which is part of a collaborative project with Oberdan Leo, Fabienne Andris and Fouad Eddahri (Immunology Laboratory, IBMM), was just published in the Journal of Immunology, the journal of the American Association of Immunologists (J Immunol 2006 : 177 ; 8185-8190). The reported findings reveal the complexity of memory T cell subsets and supports the concept that T lymphocytes expressing CCR7 - a chemokine receptor involved in the homing of lymphocytes in lymph nodes - are capable of self-renewal and thereby contribute to maintain the pool of memory cells after vaccination. These observations are important for the development of new biomarkers to assess the efficacy of vaccines.