Antibody binding profile of purified and cell-bound CD26. Designation of BT5/9 and TA5.9 to the CD26 cluster.
The CD26 activation antigen (Ag) which is expressed on a subpopulation of human T cells has been characterized as dipeptidyl peptidase IV (DPP IV, EC 3.4.14.5). In this paper, we describe the antibody binding profile of CD26/DPP IV, purified from human peripheral blood lymphocytes. The purified molecule binds to the anti-Ta1, anti-1F7 and anti-134-2C2 monoclonal antibodies (mAb), reported to react with cell-bound CD26 Ag. Among unclustered mAb recognizing T cell antigens, two, anti-BT5/9 and anti-TA5.9 were found to react with purified and cell-bound CD26 Ag. The classification of the BT5/9 Ag, the functional properties of the BT5/9+ T cell subset, as well as the in vivo effect of anti-BT5/9 mAb administration, are re-interpreted in the light of its specificity. Applying the anti-TA5.9 mAb in three color FACS analyses, we demonstrated that CD26+bright cells co-express CD45RO but not HLA-DR and CD38.
de Meester
I
I
Department of Medical Biochemistry, University of Antwerp, Wilrijk, Belgium.
Scharpé
S
S
Vanham
G
G
Bosmans
E
E
Heyligen
H
H
Vanhoof
G
G
Corte
G
G
D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism*; D000937:Antigen-Antibody Reactions; D015703:Antigens, CD / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D001666:Binding Sites, Antibody; D002846:Chromatography, Affinity; D018819:Dipeptidyl Peptidase 4; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D013601:T-Lymphocytes / Q000201:enzymology* / Q000276:immunology*
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D018819:Dipeptidyl Peptidase 4