CD8 T cell memory precursors are found in bone marrow upon activation after acute LCMV infection

ROMAGNOLI PA; PREMENKO-LANIER MF; LORIA GD; LEFRANCOIS L; ALTMAN JD

Boston, MA

Congreso; AAI IMMUNOLOGY 2012; 2012

The American Association of Immunologists, Inc.

The amount and quality of CD8T cell memory generated in response to an acute infection with an intracellular pathogen is influenced by the signals present in the tissues in which CD8 T cells are activated. Here, we investigated if location dictates the phenotype and functional properties of CD8 T cells responding to acute lymphocyticchoriomeningitis virus (LCMV) infection in different lymphoid tissues. First, we show that CD8 T cells isolated 3 days post infection (p.i.) from bone marrow (BM)displayed a memory precursor phenotype, CD62Llo CD25lo Ly6Chi different to the phenotype observed in LCMV-specific CD8 T cells from spleen or peripheral lymph nodes (PLN). Second, we show that T-bet, a T-box transcription factor found predominantly in terminally differentiated effector CD8 T cells,is almost absent in LCMV-specific CD8 T cells from BM in contrast to the high T-bet expression found on LCMV-specific CD8 T cells from PLN and spleen. Differences in T-bet are also detected after infection with vesicular stomatitis virus and L. monocytogenes. Finally, we find that CD8 T cells in BM recall better upon secondary challenge when compared to CD8 T cells from spleen or PLN. These findings strongly suggest that CD8 T cell memory precursors can arise in BM early after acute infection with an intracellular pathogen and further investigation is needed to define the environmental signals influencingCD8 T cell memory differentiation.