T cells can use either T cell receptor or CD28 receptors to absorb and internalize cell surface molecules derived from antigen-presenting cells.
At the site of contact between T cells and antigen-presenting cells (APCs), T cell receptor (TCR)-peptide-major histocompatibility complex (MHC) interaction is intensified by interactions between other molecules, notably by CD28 and lymphocyte function-associated antigen 1 (LFA-1) on T cells interacting with B7 (B7-1 and B7-2), and intracellular adhesion molecule 1 (ICAM-1), respectively, on APCs. Here, we show that during T cell-APC interaction, T cells rapidly absorb various molecules from APCs onto the cell membrane and then internalize these molecules. This process is dictated by at least two receptors on T cells, namely CD28 and TCR molecules. The biological significance of T cell uptake of molecules from APCs is unclear. One possibility is that this process may allow activated T cells to move freely from one APC to another and eventually gain entry into the circulation.
Hwang
I
I
Department of Immunology, IMM4, The Scripps Research Institute, La Jolla, California 92037, USA.
Huang
J F
JF
Kishimoto
H
H
Brunmark
A
A
Peterson
P A
PA
Jackson
M R
MR
Surh
C D
CD
Cai
Z
Z
Sprent
J
J
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D015703:Antigens, CD / Q000276:immunology*; D018122:B7-1 Antigen / Q000276:immunology*; D051940:B7-2 Antigen; D018106:CD28 Antigens / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D003713:Dendritic Cells / Q000276:immunology; D004330:Drosophila; D004705:Endocytosis / Q000276:immunology; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D018345:Mice, Knockout; D016513:Mice, SCID; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D018106:CD28 Antigens; C497965:Cd86 protein, mouse; D008562:Membrane Glycoproteins; D011948:Receptors, Antigen, T-Cell; D018799:Intercellular Adhesion Molecule-1