Details

Autor(en) / Beteiligte

• Hislop, Andrew D
• Gudgeon, Nancy H
• Callan, Margaret F. C
• Fazou, Chrysoula
• Hasegawa, Hitoshi
• Salmon, Michael
• Rickinson, Alan B

Titel

EBV-Specific CD8+ T Cell Memory: Relationships Between Epitope Specificity, Cell Phenotype, and Immediate Effector Function

Ist Teil von

• The Journal of immunology (1950), 2001-08, Vol.167 (4), p.2019-2029

Ort / Verlag

United States: Am Assoc Immnol

Erscheinungsjahr

2001

Quelle

MEDLINE

Beschreibungen/Notizen

• EBV infection in humans induces CD8+ T cell memory to viral epitopes derived from both lytic and latent cycle Ags. We have analyzed the relationship between the phenotype and function of the memory pool of T cells specific for these Ags. Lytic epitope-specific populations were heterogeneous in terms of CD45RO/RA and CD28 expression, whereas latent epitope-specific populations were uniformly CD45RO+ and CD28+, consistent with the higher antigenic challenge from lytic epitopes driving some memory cells toward a CD45RA+, CD28- phenotype. However, both types of memory population showed immediate epitope-specific cytotoxicity and type 1 cytokine production in ex vivo assays. Cytotoxic function was not associated with preactivated T cells, as EBV-specific populations were negative for activation markers such as CD69 or CD38, nor could cytotoxic function be ascribed to CD27- or CD56+ subsets, as such cells were not detected in EBV-specific memory. Furthermore, cytotoxicity was not limited to CD45RA+ and/or CD28- fractions, but also was observed in CD45RO+, CD28+ populations in lytic and latent epitope-specific memory. Cytokine (IFN-gamma, TNF-alpha) responses, measured by intracytoplasmic staining after peptide stimulation, also were detectable in CD45RO+ and RA+ subsets as well as CD28+ and CD28- subsets. Of other markers that were heterogeneous in both lytic and latent epitope populations, CCR7 gave the best discrimination of functionality; thus, CCR7+ cells consistently failed to give an IFN-gamma or TNF-alpha response, whereas many CCR7- cells were responsive. Our data are consistent with effector functions having a broad distribution among phenotypically distinct subsets of "effector memory" cells that have lost the CCR7 marker.