HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Onami, T. M. Articles by Ahmed, R. Search for Related Content PubMed PubMed Citation Articles by Onami, T. M. Articles by Ahmed, R.

Dynamic Regulation of T Cell Immunity by CD43¹

Thandi M. Onami^*, Laurie E. Harrington^*, Matthew A. Williams, Marisa Galvan, Christian P. Larsen, Thomas C. Pearson, N. Manjunath^¶, Linda G. Baum, Brad D. Pearce and Rafi Ahmed^2,*

^* Emory Vaccine Center and Department of Microbiology and Immunology, Department of Surgery, Carlos and Marguerite Mason Transplantation Research Center, and Department of Psychiatry, Emory School of Medicine, Atlanta, GA 30322; Department of Pathology and Laboratory Medicine, University of California School of Medicine, Los Angeles, CA 90095; and ^¶ Center for Blood Research, Harvard School of Medicine, Boston, MA 02115

During a viral response, Ag-specific effector T cells show dramatically increased binding by the mAb 1B11 and the lectin peanut agglutinin (PNA). We investigated the contribution of CD43 expression to 1B11 and PNA binding as well as its role in generation and maintenance of a CD8 T cell response. Analysis of CD43^-/- mice revealed no increased 1B11 binding and reduced PNA binding on virus-specific CD8 T cells from -/- mice compared with +/+ mice. Furthermore, we examined the role of CD43 in the kinetics of an immune response. We show that CD43 expression modestly effects generation of a primary virus-specific CD8 T cell response in vivo but plays a more significant role in trafficking of CD8 T cells to tissues such as the brain. More interestingly, CD43 plays a role in the contraction of the immune response, with CD43^-/- mice showing increased numbers of Ag-specific CD8 T cells following initial expansion. Following the peak of expansion, Ag-specific CD8 T cells from -/- mice show similar proliferation but demonstrate increased Bcl-2 levels and decreased apoptosis of Ag-specific effector CD8 T cells in vitro. Consistent with a delay in the down-modulation of the immune response, following chronic viral infection CD43^-/- mice show increased morbidity. These data suggest a dynamic role of CD43 during an immune response: a positive regulatory role in costimulation and trafficking of T cells to the CNS and a negative regulatory role in the down-modulation of an immune response.