ଝଝ This text is protected by copyright owned by SPILF. Reproduction and distribution rights are granted by SPILF on request, provided the text is reproduced in full, with no addition or deletion, and provided SPILF and the references of the original article published in Médecine et Maladies Infectieuses are indicated. Chikungunya (CHIK) is both an arbovirus transmitted by Aedes mosquitoes and an arthrogenic alphavirus, the clinical consequences of which were revealed in France by the southwest Indian Ocean outbreak (Mayotte, Reunion) in 2005-2006. The recent epidemic spread of CHIK in the French South American and Pacific territories (departments) and communities led to a steady increase of infected individuals, confronting local and metropolitan healthcare professionals with the difficulties http://dx.

SummaryAging is generally associated with an increased predisposition to infectious diseases and cancers, related in part to the development of immune senescence, a process that affects all cell compartments of the immune system. Although many studies have investigated the effects of age on natural killer (NK) cells, their conclusions remain controversial because the diverse health status of study subjects resulted in discordant findings. To clarify this situation, we conducted the first extensive phenotypic and functional analysis of NK cells from healthy subjects, comparing NK cells derived from newborn (cord blood), middle-aged (18-60 years), old (60-80 years), and very old (80-100 years) subjects. We found that NK cells in cord blood displayed specific features associated with immaturity, including poor expression of KIR and LIR-1 ⁄ ILT-2 and high expression of both NKG2A and IFN-c. NK cells from older subjects, on the other hand, preserved their major phenotypic and functional characteristics, but with their mature features accentuated. These include a profound decline of the CD56 bright subset, a specific increase in LIR-1 ⁄ ILT-2, and a perfect recovering of NK-cell function following IL2-activation in very old subjects. We conclude that the preservation of NK cell features until very advanced age may contribute to longevity and successful aging.