Abstract
Combination immunotherapy with anti-CD20 and anti-CD22 mAbs shows promising activity in non-Hodgkin lymphoma. Therefore, bispecific mAbs (bsAbs) were recombinantly constructed from veltuzumab (humanized anti-CD20) and epratuzumab (humanized anti-CD22) and evaluated in vitro and in vivo. While none of the parental mAbs alone or mixed had notable antiproliferative activity against Burkitt lymphoma cells when not cross-linked, the bsAbs [eg, anti-CD20 IgG-anti-CD22 (scFv)(2)] were inhibitory without cross-linking and synergistic with B-cell antigen (BCR)-mediated inhibition. The bsAbs demonstrated higher antibody-dependent cellulary cytoxicity (ADCC) activity than the parental mAbs, but not complement-dependent cytoxicity (CDC) of the parental CD20 mAb. Cross-linking both CD20 and CD22 with the bsAbs resulted in the prominent redistribution of not only CD20 but also CD22 and BCR into lipid rafts. Surprisingly, appreciable translocation of CD22 into lipid rafts was also observed after treatment with epratuzumab. Finally, the bsAbs inhibited Daudi lymphoma transplant growth, but showed a significant advantage over the parental anti-CD20 mAb only at the highest dose tested. These results suggest that recombinantly fused, complementary, bispecific, anti-CD20/22 antibodies exhibit functional features distinct from their parental antibodies, perhaps representing new candidate therapeutic molecules.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
