T helper (Th) 2 predominance in atopic diseases is due to preferential apoptosis of circulating memory/effector Th1 cells


Akdis M., Trautmann A., Klunker S., Daigle I., Kucuksezer U. C., Deglmann W., ...More

FASEB JOURNAL, vol.17, no.9, pp.1026-1035, 2003 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 17 Issue: 9
  • Publication Date: 2003
  • Doi Number: 10.1096/fj.02-1070com
  • Journal Name: FASEB JOURNAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1026-1035
  • Istanbul University Affiliated: Yes

Abstract

T cells constitute a large population of cellular infiltrate in atopic/allergic inflammation and a dysregulated, Th2-biased peripheral immune response appears to be an important pathogenetic factor. In atopic dermatitis, circulating cutaneous lymphocyte-associated antigen-bearing (CLA(+)) CD45RO(+) T cells with skin-specific homing property represent an activated memory/effector T cell subset. They express high levels of Fas and Fas ligand and undergo activation-induced apoptosis. The freshly purified (CLA(+)) CD45RO(+) T cells of atopic individuals display distinct features of in vivo-triggered apoptosis such as procaspase degradation and active caspase-8 formation. In particular, the Th1 compartment of activated memory/effector T cells selectively undergoes activation-induced cell death, skewing the immune response toward surviving Th2 cells in atopic dermatitis patients. The apoptosis of circulating memory/effector T cells was confined to atopic individuals whereas non-atopic patients such as psoriasis, intrinsic-type asthma, contact dermatitis, intrinsic type of atopic dermatitis, bee venom allergic patients, and healthy controls showed no evidence for enhanced T cell apoptosis in vivo. These results define a novel mechanism for peripheral Th2 response in atopic diseases.

T cells constitute a large population of cellular infiltrate in atopic/allergic inflammation and a dysregulated, Th2-biased peripheral immune response appears to be an important pathogenetic factor. In atopic dermatitis, circulating cutaneous lymphocyte-associated antigen-bearing (CLA(+)) CD45RO(+) T cells with skin-specific homing property represent an activated memory/effector T cell subset. They express high levels of Fas and Fas ligand and undergo activation-induced apoptosis. The freshly purified (CLA(+)) CD45RO(+) T cells of atopic individuals display distinct features of in vivo-triggered apoptosis such as procaspase degradation and active caspase-8 formation. In particular, the Th1 compartment of activated memory/effector T cells selectively undergoes activation-induced cell death, skewing the immune response toward surviving Th2 cells in atopic dermatitis patients. The apoptosis of circulating memory/effector T cells was confined to atopic individuals whereas non-atopic patients such as psoriasis, intrinsic-type asthma, contact dermatitis, intrinsic type of atopic dermatitis, bee venom allergic patients, and healthy controls showed no evidence for enhanced T cell apoptosis in vivo. These results define a novel mechanism for peripheral Th2 response in atopic diseases.