Production and Properties of Monoclonal Antibodies against Human Ecto-5′-Nucleotidase

The membrane enzyme 5′-nucleotidase (5′-N) has been characterized as an ectoenzyme in many different tissues of different species. The ecto-property means that a major portion of this molecule including the active center and the carbohydrate side chains is located in the extracellular space. Thus, the enzyme represents an interesting surface marker. This is especially true in lymphoid cells, where we observe charcteristic differences in expression of this marker in various subpopulations, in cell lines and in different forms of leukemias and lymphomas. The latter observation can even be used diagnostically in selected cases 1,2. Therefore, a method of detection of the molecule independent of the overall measurement of enzyme activity, for example by monoclonal antibodies (MABs) seemed desirable. In addition specific immunological reagents should be useful tools for further biochemical studies. In the foliowing a number of monoclonal antibodies against the human enzyme shall be described.