Abstract
Telomeres, structures on the ends of linear chromosomes, function to maintain chromosomal integrity. Telomere shortening occurs with cell division and provides a mechanism for limiting the replicative potential of normal human somatic cells. Telomerase, a ribonucleoprotein enzyme, synthesize telomeric repeats on chromosomal termini, potentially extending the capacity for cell division. The present study demonstrates that resting T cells express little/no activity, and optimal Ag-specific induction of telomerase activity in vitro requires both TCR and CD28-B7 costimulatory signals. Regulation of telomerase in T cells during in vivo Ag-dependent activation was also assessed by adoptive transfer of TCR transgenic T cells and subsequent Ag challenge. Under these conditions, telomerase was induced in transgenic T cells coincident with a phase of extensive clonal expansion. These findings suggests that telomerase may represent an adoptive response that functions to preserve replicative potential in Ag-reactive lymphocytes.
Original language | English (US) |
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Pages (from-to) | 5702-5706 |
Number of pages | 5 |
Journal | Journal of Immunology |
Volume | 160 |
Issue number | 12 |
State | Published - Jun 15 1998 |