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Vol. 56, No. 4, 2010
Issue release date: June 2010
Editor's Choice -- Free Access
Gerontology 2010;56:390–403
(DOI:10.1159/000268620)

Telomeres and Immunological Diseases of Aging

Andrews N.P. · Fujii H. · Goronzy J.J. · Weyand C.M.
Lowance Center for Human Immunology, Department of Medicine, Emory University School of Medicine, Atlanta, Ga., USA
email Corresponding Author

Abstract

A defining feature of the eukaryotic genome is the presence of linear chromosomes. This arrangement, however, poses several challenges with regard to chromosomal replication and maintenance. To prevent the loss of coding sequences and to suppress gross chromosomal rearrangements, linear chromosomes are capped by repetitive nucleoprotein structures, called telomeres. Each cell division results in a progressive shortening of telomeres that, below a certain threshold, promotes genome instability, senescence, and apoptosis. Telomeric erosion, maintenance, and repair take center stage in determining cell fate. Cells of the immune system are under enormous proliferative demand, stressing telomeric intactness. Lymphocytes are capable of upregulating telomerase, an enzyme that can elongate telomeric sequences and, thus, prolong cellular lifespan. Therefore, telomere dynamics are critical in preserving immune function and have become a focus for studies of immunosenescence and autoimmunity. In this review, we describe the role of telomeric nucleoproteins in shaping telomere architecture and in suppressing DNA damage responses. We summarize new insights into the regulation of telomerase activity, hereditary disorders associated with telomere dysfunction, the role of telomere loss in immune aging, and the impact of telomere dysfunction in chronic inflammatory disease.


 goto top of outline Key Words

  • Telomeres
  • Aging
  • Immunosenescence

 goto top of outline Abstract

A defining feature of the eukaryotic genome is the presence of linear chromosomes. This arrangement, however, poses several challenges with regard to chromosomal replication and maintenance. To prevent the loss of coding sequences and to suppress gross chromosomal rearrangements, linear chromosomes are capped by repetitive nucleoprotein structures, called telomeres. Each cell division results in a progressive shortening of telomeres that, below a certain threshold, promotes genome instability, senescence, and apoptosis. Telomeric erosion, maintenance, and repair take center stage in determining cell fate. Cells of the immune system are under enormous proliferative demand, stressing telomeric intactness. Lymphocytes are capable of upregulating telomerase, an enzyme that can elongate telomeric sequences and, thus, prolong cellular lifespan. Therefore, telomere dynamics are critical in preserving immune function and have become a focus for studies of immunosenescence and autoimmunity. In this review, we describe the role of telomeric nucleoproteins in shaping telomere architecture and in suppressing DNA damage responses. We summarize new insights into the regulation of telomerase activity, hereditary disorders associated with telomere dysfunction, the role of telomere loss in immune aging, and the impact of telomere dysfunction in chronic inflammatory disease.

Copyright © 2009 S. Karger AG, Basel


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 goto top of outline Author Contacts

Cornelia M. Weyand, MD, PhD
Lowance Center for Human Immunology, Emory University
101 Woodruff Circle
Atlanta, GA 30322 (USA)
Tel. +1 404 727 7310, Fax +1 404 727 7371, E-Mail cweyand@emory.edu


 goto top of outline Article Information

Received: May 29, 2009
Accepted: September 7, 2009
Published online: December 17, 2009
Number of Print Pages : 14
Number of Figures : 3, Number of Tables : 1, Number of References : 148


 goto top of outline Publication Details

Gerontology (International Journal of Experimental, Clinical, Behavioural and Technological Gerontology)

Vol. 56, No. 4, Year 2010 (Cover Date: June 2010)

Journal Editor: Wick G. (Innsbruck)
ISSN: 0304-324X (Print), eISSN: 1423-0003 (Online)

For additional information: http://www.karger.com/GER


Copyright / Drug Dosage / Disclaimer

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

Abstract

A defining feature of the eukaryotic genome is the presence of linear chromosomes. This arrangement, however, poses several challenges with regard to chromosomal replication and maintenance. To prevent the loss of coding sequences and to suppress gross chromosomal rearrangements, linear chromosomes are capped by repetitive nucleoprotein structures, called telomeres. Each cell division results in a progressive shortening of telomeres that, below a certain threshold, promotes genome instability, senescence, and apoptosis. Telomeric erosion, maintenance, and repair take center stage in determining cell fate. Cells of the immune system are under enormous proliferative demand, stressing telomeric intactness. Lymphocytes are capable of upregulating telomerase, an enzyme that can elongate telomeric sequences and, thus, prolong cellular lifespan. Therefore, telomere dynamics are critical in preserving immune function and have become a focus for studies of immunosenescence and autoimmunity. In this review, we describe the role of telomeric nucleoproteins in shaping telomere architecture and in suppressing DNA damage responses. We summarize new insights into the regulation of telomerase activity, hereditary disorders associated with telomere dysfunction, the role of telomere loss in immune aging, and the impact of telomere dysfunction in chronic inflammatory disease.



 goto top of outline Author Contacts

Cornelia M. Weyand, MD, PhD
Lowance Center for Human Immunology, Emory University
101 Woodruff Circle
Atlanta, GA 30322 (USA)
Tel. +1 404 727 7310, Fax +1 404 727 7371, E-Mail cweyand@emory.edu


 goto top of outline Article Information

Received: May 29, 2009
Accepted: September 7, 2009
Published online: December 17, 2009
Number of Print Pages : 14
Number of Figures : 3, Number of Tables : 1, Number of References : 148


 goto top of outline Publication Details

Gerontology (International Journal of Experimental, Clinical, Behavioural and Technological Gerontology)

Vol. 56, No. 4, Year 2010 (Cover Date: June 2010)

Journal Editor: Wick G. (Innsbruck)
ISSN: 0304-324X (Print), eISSN: 1423-0003 (Online)

For additional information: http://www.karger.com/GER


Copyright / Drug Dosage

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

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