Functional Study of a Camelid Single Domain Anti-CD22 Antibody

Variable antigen-binding domain of camelid single chain antibodies (VHH, Nanobody) and its conjugates are considered among very promising candidates in tumor diagnosis and treatment because of its small size, stability, and favorable bio-distribution. CD22 is a receptor that is expressed on most B cells and modulates their function. Targeting CD22 in B cell malignancies and disorders by monoclonal antibodies has shown promising results in vitro and in clinical trials. In this study, we investigate the impact of an anti-human CD22 VHH binding to CD22 on B cells and its internalization following attachment. Our findings demonstrate the proliferation inhibiting of these cells with no effect on apoptosis, in addition to the rapid internalization of the VHH.