177Lu-antibody conjugates for single-cell kill of B-lymphoma cells in vitro and for therapy of micrometastases in vivo.

Antibodies (Abs) conjugated to 177Lu, a relatively low-energy beta-particle emitter, were evaluated in vitro for their cytotoxic activity and in vivo for their therapeutic activity against disseminated B-cell lymphoma xenografts in SCID mice. 177Lu was compared with other beta-particle emitters ((131)I and 90Y), and also with emitters of low-energy electrons (LEEs, meaning Auger and conversion electrons of < 50 keV). The Abs used reacted with CD20, CD74 or HLA-DR, and the target cell was the Raji B lymphoma.

Therapy of small subcutaneous B-lymphoma xenografts with antibodies conjugated to radionuclides emitting low-energy electrons.

Purpose: Radionuclides emitting low-energy electrons (Auger and conversion electrons of <50 keV) are potentially useful for cancer therapy when conjugated to an antibody, because they can irradiate the cell to which they bind while producing relatively little irradiation of surrounding cells and tissues. We showed previously the ability of such antibody conjugates to treat micrometastatic, disseminated human B-lymphoma in a severe combined immunodeficient mouse model using an anti-CD74 antibody. In this study, we have evaluated the ability of such conjugates to treat s.

Experimental therapy of disseminated B-Cell lymphoma xenografts with 213Bi-labeled anti-CD74.

A (213)Bi-labeled antibody to CD74 was evaluated as a therapeutic agent for B-cell lymphoma. The alpha-particle emission, with a half-life of 46 min, is appropriate for therapy of micrometastases. The labeled Ab retained full immunoreactivity, and was potent at single-cell kill of the Raji B-lymphoma cell line.