CD2-mediated adhesion facilitates T lymphocyte antigen recognition function.
The CD2 T lymphocyte-surface glycoprotein serves to mediate adhesion between T lymphocytes and their cognate cellular partners which express the specific ligand LFA-3. In addition, CD2 by itself or in conjunction with T-cell receptor stimulation, transduces signals resulting in T-lymphocyte activation. One or both of these functions seems to be physiologically important, given that certain anti-CD2 monoclonal antibodies block T-cell activation and that antigen-responsive memory T cells express a high level of CD2 relative to virgin T cells, which are largely antigen-unresponsive. Nevertheless, the contribution of the individual CD2 functions in T-cell responses has not been independently examined. To this end, human CD2 complementary DNAs encoding an intact LFA-3-binding adhesion domain, but lacking a functional cytoplasmic signal transduction element (CD2trans-), were introduced into an ovalbumin-specific, I-Ad restricted murine T-cell hybridoma. The antigen-specific response of T hybridoma cells expressing human CD2trans- protein was enhanced up to 400% when the human LFA-3 ligand was introduced into the I-Ad expressing murine antigen-presenting cells. In contrast, no augmentation was observed if human LFA-3 was absent or expressed on a third-party cell lacking the I-Ad restriction element. These results directly demonstrate the functional significance of adhesion events mediated between CD2 on the antigen-responsive T lymphocyte and LFA-3 on the presenting cell in optimizing antigen-specific T-cell activation.
Moingeon
P
P
Laboratory of Immunobiology, Dana-Farber Cancer Institute, Boston, Massachusetts.
Chang
H C
HC
Wallner
B P
BP
Stebbins
C
C
Frey
A Z
AZ
Reinherz
E L
EL
D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000502:physiology*; D018801:CD2 Antigens; D002448:Cell Adhesion; D002460:Cell Line; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis; D007700:Kinetics; D008223:Lymphoma; D008562:Membrane Glycoproteins / Q000502:physiology*; D051379:Mice; D011971:Receptors, Immunologic / Q000235:genetics / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic