Phenotypic and Functional Separation of Memory and Effector Human CD8+ T Cells

摘要: Human CD8+ memory- and effector-type T cells are poorly defined. We show here that, next to a naive compartment, two discrete primed subpopulations can be found within the circulating human cell subset. First, CD45RA−CD45R0+ reminiscent of memory-type in that they express elevated levels CD95 (Fas) integrin family members CD11a, CD18, CD29, CD49d, CD49e, compared cells, able secrete not only interleukin (IL) 2 but also interferon γ, tumor necrosis factor α, IL-4. This subset does exert cytolytic activity without prior vitro stimulation contain virus-specific cytotoxic lymphocyte (CTL) precursors. A second population is characterized by CD45RA expression with concomitant absence costimulatory molecules CD27 CD28. The CD8+CD45RA+CD27− contains expressing high CD11b, whereas CD62L (L-selectin) expressed. These do IL-2 or -4 produce IFN-γ TNF-α. In accordance this finding, contained subpopulation depend for proliferation on exogenous growth factors such as -15. Interestingly, parallel effector CTLs, abundantly Fas-ligand mRNA, perforin granzyme B, have prestimulation. Based both phenotypic functional properties, we conclude separated distinct entities