Functional plasticity of an antigen-specific memory CD4 T cell population.
The protective nature of memory immune responses is attributed largely to terminally differentiated memory T cells that retain memory of the antigen via the antigen receptor and memory of the effector functions that initially cleared the pathogen. It is not known whether a given population of antigen-specific memory T cells is endowed with functional flexibility to provide protective responses against antigens reencountered in different immunological contexts. Here, we examine functional properties of influenza hemagglutinin (HA)-specific memory CD4 T cells recovered from adoptive hosts that received in vitro-activated HA-specific T cell receptor-transgenic CD4 T cells 2 months to 1 year previously. We demonstrate that this HA-specific memory CD4 T cell population bearing a clonal T cell receptor can produce predominantly T helper 1 or T helper 2 effector cytokines depending on the nature of the recall stimulus. Our findings reveal remarkable functional plasticity within an antigen-specific memory T cell population and have direct implications for modulating memory T cell function in vaccine design and treatments for autoimmune diseases.
Ahmadzadeh
Mojgan
M
Department of Surgery, University of Maryland School of Medicine, MSTF Building, Room 400, 685 West Baltimore Street, Baltimore, MD 21201, USA.
Farber
Donna L
DL
D019264:Adoptive Transfer; D000818:Animals; D000941:Antigens / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation; D016207:Cytokines / Q000096:biosynthesis; D007156:Immunologic Memory; D051379:Mice; D008807:Mice, Inbred BALB C
D000941:Antigens; D016207:Cytokines