Association of CD2 and T200 (CD45) in mouse T lymphocytes.
A monoclonal antibody (mAb 12-15) reactive with the mouse CD2 was found to co-precipitate a high-molecular-weight glycoprotein from mouse thymocyte, splenic lymphocyte, Con A blast, and T cell tumor detergent lysates which was identified as the leukocyte common T 200 glycoprotein (CD45). The reactivity was specific for CD2 since antibodies to CD3 did not co-precipitate the T200 glycoprotein. mAb 12-15 did not react with immunoaffinity-purified T200 glycoprotein, ruling out the possibility that the antibody detected a cross-reactive epitope. Biochemical data indicated that the association of CD2 with T200 was not generated during lysis of the cell and that the molecular complex was non-covalently linked since it could be destroyed by high salt washing or boiling in SDS. Distribution analysis in Triton X114-H2O revealed that, in contrast to free T200 molecules, the complexed T200 was enriched in the detergents phase. To investigate the CD2-T200 association in more detail at the cell surface, modulation of CD2 and T200 was studied. Modulation could be induced on Con A blasts by monoclonal antibodies followed by cross-linking with a FITC-conjugated second antibody. Within 24 h the expression of CD2 or T200 was reduced to approximately 10-20% of the initial value on the majority of cells. However, two-color fluorescence showed that modulation of CD2 did not lead to co-modulation of CD3 or T200. A possible physiological role of CD2-T200 complexes is discussed.
Altevogt
P
P
Institut für Immunologie und Genetik, Deutsches Krebsforschungszentrum, Heidelberg, FRG.
Schreck
J
J
Schraven
B
B
Meuer
S
S
Schirrmacher
V
V
Mitsch
A
A
D000818:Animals; D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000302:isolation & purification; D000945:Antigens, Differentiation, T-Lymphocyte / Q000302:isolation & purification; D018801:CD2 Antigens; D006649:Histocompatibility Antigens / Q000302:isolation & purification; D017493:Leukocyte Common Antigens; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000276:immunology / Q000302:isolation & purification; D051379:Mice; D008811:Mice, Inbred DBA; D011971:Receptors, Immunologic / Q000302:isolation & purification; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D006649:Histocompatibility Antigens; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; D017493:Leukocyte Common Antigens