Changes in telomerase activity and telomere length during human T lymphocyte senescence

Chong-Xian Pan, Bao Hua Xue, Thomas M. Ellis, David J. Peace, Manuel O. Díaz

Research output: Contribution to journalArticle

56 Citations (Scopus)

Abstract

It has been proposed that telomeres shorten with every cell cycle because the normal mechanism of DNA replication cannot replicate the end sequences of the lagging DNA strand. Telomerase, a ribonucleoprotein enzyme that synthesizes telomeric DNA repeats at the DNA 3' ends of eukaryotic chromosomes, can compensate for such shortening, by extending the template of the lagging strand. Telomerase activity has been identified in human germline cells and in neoplastic immortal somatic cells, but not in most normal somatic cells, which senesce after a certain number of cell divisions. We and others have found that telomerase activity is present in normal human lymphocytes and is upregulated when the cells are activated. But, unlike the immortal cell lines, presence of telomerase activity is not sufficient to make T cells immortal and telomeres from these cells shorten continuously during in vitro culture. After senescence, telomerase activity, as detected by the TRAP technique, was downregulated. A cytotoxic T lymphocyte (CTL) cell line that was established in the laboratory has very short terminal restriction fragments (TRFs). Telomerase activity in this cell line is induced during activation and this activity is tightly correlated with cell proliferation. The level of telomerase activity in activated peripheral blood T cells, the CTL cell line, and two leukemia cell lines does not correlate with the average TRF length, suggesting that other factors besides telomerase activity are involved in the regulation of telomere length.

Original languageEnglish (US)
Pages (from-to)346-353
Number of pages8
JournalExperimental Cell Research
Volume231
Issue number2
DOIs
StatePublished - Mar 15 1997
Externally publishedYes

Fingerprint

Telomerase
Telomere
T-Lymphocytes
Cell Line
Telomere Shortening
Cytotoxic T-Lymphocytes
Ribonucleoproteins
DNA
DNA Replication
Cell Division
Blood Cells
Cell Cycle
Leukemia
Down-Regulation
Chromosomes
Cell Proliferation
Lymphocytes
Enzymes

ASJC Scopus subject areas

  • Cell Biology

Cite this

Changes in telomerase activity and telomere length during human T lymphocyte senescence. / Pan, Chong-Xian; Xue, Bao Hua; Ellis, Thomas M.; Peace, David J.; Díaz, Manuel O.

In: Experimental Cell Research, Vol. 231, No. 2, 15.03.1997, p. 346-353.

Research output: Contribution to journalArticle

Pan, Chong-Xian ; Xue, Bao Hua ; Ellis, Thomas M. ; Peace, David J. ; Díaz, Manuel O. / Changes in telomerase activity and telomere length during human T lymphocyte senescence. In: Experimental Cell Research. 1997 ; Vol. 231, No. 2. pp. 346-353.
@article{d5b7ffc0a63142048bee9c06e37ae5df,
title = "Changes in telomerase activity and telomere length during human T lymphocyte senescence",
abstract = "It has been proposed that telomeres shorten with every cell cycle because the normal mechanism of DNA replication cannot replicate the end sequences of the lagging DNA strand. Telomerase, a ribonucleoprotein enzyme that synthesizes telomeric DNA repeats at the DNA 3' ends of eukaryotic chromosomes, can compensate for such shortening, by extending the template of the lagging strand. Telomerase activity has been identified in human germline cells and in neoplastic immortal somatic cells, but not in most normal somatic cells, which senesce after a certain number of cell divisions. We and others have found that telomerase activity is present in normal human lymphocytes and is upregulated when the cells are activated. But, unlike the immortal cell lines, presence of telomerase activity is not sufficient to make T cells immortal and telomeres from these cells shorten continuously during in vitro culture. After senescence, telomerase activity, as detected by the TRAP technique, was downregulated. A cytotoxic T lymphocyte (CTL) cell line that was established in the laboratory has very short terminal restriction fragments (TRFs). Telomerase activity in this cell line is induced during activation and this activity is tightly correlated with cell proliferation. The level of telomerase activity in activated peripheral blood T cells, the CTL cell line, and two leukemia cell lines does not correlate with the average TRF length, suggesting that other factors besides telomerase activity are involved in the regulation of telomere length.",
author = "Chong-Xian Pan and Xue, {Bao Hua} and Ellis, {Thomas M.} and Peace, {David J.} and D{\'i}az, {Manuel O.}",
year = "1997",
month = "3",
day = "15",
doi = "10.1006/excr.1997.3475",
language = "English (US)",
volume = "231",
pages = "346--353",
journal = "Experimental Cell Research",
issn = "0014-4827",
publisher = "Academic Press Inc.",
number = "2",

}

TY - JOUR

T1 - Changes in telomerase activity and telomere length during human T lymphocyte senescence

AU - Pan, Chong-Xian

AU - Xue, Bao Hua

AU - Ellis, Thomas M.

AU - Peace, David J.

AU - Díaz, Manuel O.

PY - 1997/3/15

Y1 - 1997/3/15

N2 - It has been proposed that telomeres shorten with every cell cycle because the normal mechanism of DNA replication cannot replicate the end sequences of the lagging DNA strand. Telomerase, a ribonucleoprotein enzyme that synthesizes telomeric DNA repeats at the DNA 3' ends of eukaryotic chromosomes, can compensate for such shortening, by extending the template of the lagging strand. Telomerase activity has been identified in human germline cells and in neoplastic immortal somatic cells, but not in most normal somatic cells, which senesce after a certain number of cell divisions. We and others have found that telomerase activity is present in normal human lymphocytes and is upregulated when the cells are activated. But, unlike the immortal cell lines, presence of telomerase activity is not sufficient to make T cells immortal and telomeres from these cells shorten continuously during in vitro culture. After senescence, telomerase activity, as detected by the TRAP technique, was downregulated. A cytotoxic T lymphocyte (CTL) cell line that was established in the laboratory has very short terminal restriction fragments (TRFs). Telomerase activity in this cell line is induced during activation and this activity is tightly correlated with cell proliferation. The level of telomerase activity in activated peripheral blood T cells, the CTL cell line, and two leukemia cell lines does not correlate with the average TRF length, suggesting that other factors besides telomerase activity are involved in the regulation of telomere length.

AB - It has been proposed that telomeres shorten with every cell cycle because the normal mechanism of DNA replication cannot replicate the end sequences of the lagging DNA strand. Telomerase, a ribonucleoprotein enzyme that synthesizes telomeric DNA repeats at the DNA 3' ends of eukaryotic chromosomes, can compensate for such shortening, by extending the template of the lagging strand. Telomerase activity has been identified in human germline cells and in neoplastic immortal somatic cells, but not in most normal somatic cells, which senesce after a certain number of cell divisions. We and others have found that telomerase activity is present in normal human lymphocytes and is upregulated when the cells are activated. But, unlike the immortal cell lines, presence of telomerase activity is not sufficient to make T cells immortal and telomeres from these cells shorten continuously during in vitro culture. After senescence, telomerase activity, as detected by the TRAP technique, was downregulated. A cytotoxic T lymphocyte (CTL) cell line that was established in the laboratory has very short terminal restriction fragments (TRFs). Telomerase activity in this cell line is induced during activation and this activity is tightly correlated with cell proliferation. The level of telomerase activity in activated peripheral blood T cells, the CTL cell line, and two leukemia cell lines does not correlate with the average TRF length, suggesting that other factors besides telomerase activity are involved in the regulation of telomere length.

UR - http://www.scopus.com/inward/record.url?scp=0031569378&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031569378&partnerID=8YFLogxK

U2 - 10.1006/excr.1997.3475

DO - 10.1006/excr.1997.3475

M3 - Article

VL - 231

SP - 346

EP - 353

JO - Experimental Cell Research

JF - Experimental Cell Research

SN - 0014-4827

IS - 2

ER -