Specifically targeting the CD22 receptor of human B-cell lymphomas with RNA damaging agents: a new generation of therapeutics.

Targeting CD22 on human B-cells with a monoclonal antibody conjugated to a cytotoxic RNAse causes potent and specific killing of the lymphoma cells in vitro. This translates to anti-tumor effects in human lymphoma models in SCID mice. RNA damage caused by RNAses could be an important alternative to standard DNA-damaging chemotherapeutics. A second generation construct with an improved recombinant cytotoxic RNAse is described. Targeted RNAses may overcome problems of toxicity and immunogenicity associated with plant or bacterial toxin-containing immunoconjugates.