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Differential expression of Ly6C and T-bet distinguish effector and memory Th1 CD4(+) cell properties during viral infection.

Department of Immunobiology, Yale University School of Medicine, New Haven, CT 06520, USA.
Immunity (Impact Factor: 19.75). 10/2011; 35(4):633-46. DOI: 10.1016/j.immuni.2011.08.016
Source: PubMed

ABSTRACT CD4(+) T cells differentiate into multiple effector types, but it is unclear how they form memory T cells during infection in vivo. Profiling virus-specific CD4(+) T cells revealed that effector cells with T helper 1 (Th1) or T follicular helper (Tfh) cell characteristics differentiated into memory cells, although expression of Tfh cell markers declined over time. In contrast to virus-specific effector CD8(+) T cells, increased IL-7R expression was not a reliable marker of CD4(+) memory precursor cells. However, decreased Ly6C and T-bet (Tbx21) expression distinguished a subset of Th1 cells that displayed greater longevity and proliferative responses to secondary infection. Moreover, the gene expression profile of Ly6C(lo)T-bet(int) Th1 effector cells was virtually identical to mature memory CD4(+) T cells, indicating early maturation of memory CD4(+) T cell features in this subset during acute viral infection. This study provides a framework for memory CD4(+) T cell development after acute viral infection.

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