Abstract
Adoptive T-cell therapy with CD8+ CTLs is often characterized by poor persistence of the transferred T cells and limited effector responses. Improved persistence and therapeutic efficacy have been noted when antigen-activated CD8+ T cells express properties of memory cells. The current study was undertaken to more precisely characterize the development of memory-like CD8+ T cells from short-term CTLs in vitro and upon transfer in vivo, including their antitumor activity. Ovalbumin (OVA)-specific OT-I CTLs acquired phenotypic and functional properties of memory cells 2 to 3 days later either by lowering the concentration of antigen to a level that does not support primary responses and providing a survival signal through transgenic Bcl-2 in vitro or simply by transferring early day 3 CTLs to antigen-free lymphoid-replete mice. In lymphoid-replete mice, established OVA-expressing E.G7 tumor was rejected by short-term CTLs that simultaneously acquired memory-like properties in secondary lymphoid tissues, where tumor antigen level remained low. Collectively, these data indicate that CTLs readily converted to memory-like cells upon lowering antigen to a concentration that selectively supports memory responses and suggest that such conversion predicts successful adoptive immunotherapy.
Original language | English (US) |
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Pages (from-to) | 2984-2992 |
Number of pages | 9 |
Journal | Cancer Research |
Volume | 68 |
Issue number | 8 |
DOIs | |
State | Published - Apr 15 2008 |
ASJC Scopus subject areas
- Oncology
- Cancer Research