| abstract |
The invention relates to a ligand or functional derivative thereof, with at least one specificity for the adenosine deaminase (ADA) binding site of CD26, being for example a monoclonal antibody or a modified version of adenosine deaminase. The functional derivative can be an Fab-, Fab'-, F(ab)2-, an scFv- or Fv-fragment of the monoclonal antibody or a chimeric antibody. Apart from this the functional derivative can be a conjugate between the ligand or a functional component thereof and a secondary molecule. The ligands according to the invention can be used as a therapeutic agent for stimulating the proliferation of T-lymphocytes, as an immuno-suppressing agent, as a diagnostic agent in immuno-enzymatic assays, for monitoring malignantly transformed melanocytes or in imaging techniques or as therapeutic agent against HIV-infection. |