Are you Dionysos S Slaga?

Claim your profile

Publications (2)16.14 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Fc receptor-like 5 (FcRL5/FcRH5/IRTA2/CD307) is a surface protein expressed selectively on B cells and plasma cells. We found that FcRL5 was expressed at elevated levels on the surface of plasma cells from the bone marrow of patients diagnosed with multiple myeloma. This prevalence in multiple myeloma and narrow pattern of normal expression indicate that FcRL5 could be a target for antibody-based therapies for multiple myeloma, particularly antibody-drug conjugates (ADC), potent cytotoxic drugs linked to antibodies via specialized chemical linkers, where limited expression on normal tissues is a key component to their safety. We found that FcRL5 is internalized upon antibody binding, indicating that ADCs to FcRL5 could be effective. Indeed, we found that FcRL5 ADCs were efficacious in vitro and in vivo but the unconjugated antibody was not. The two most effective consisted of our anti-FcRL5 antibody conjugated through cysteines to monomethylauristatin E (MMAE) by a maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (MC-vcPAB) linker (anti-FcRL5-MC-vcPAB-MMAE) or conjugated via lysines to the maytansinoid DM4 through a disulfide linker (anti-FcRL5-SPDB-DM4). These two ADCs were highly effective in vivo in combination with bortezomib or lenalidomide, drugs in use for the treatment of multiple myeloma. These data show that the FcRL5 ADCs described herein show promise as an effective treatment for multiple myeloma. Mol Cancer Ther; 11(10); 2222-32. ©2012 AACR.
    Full-text · Article · Jul 2012 · Molecular Cancer Therapeutics
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Targeting cytotoxic drugs to cancer cells using antibody-drug conjugates (ADCs), particularly those with stable linkers between the drug and the antibody, could be an effective cancer treatment with low toxicity. However, for stable-linker ADCs to be effective, they must be internalized and degraded, limiting potential targets to surface antigens that are trafficked to lysosomes. CD79a and CD79b comprise the hetrodimeric signaling component of the B-cell receptor, and are attractive targets for the use of ADCs because they are B-cell-specific, expressed in non-Hodgkin lymphomas (NHL), and are trafficked to a lysosomal-like compartment as part of antigen presentation. We show here that the stable-linker ADCs anti-CD79b-MCC-DM1 and anti-CD79b-MC-MMAF are capable of target-dependent killing of nonHodgkin lymphoma cell lines in vitro. Further, these 2 ADCs are equally effective as low doses in xenograft models of follicular, mantle cell, and Burkitt lymphomas, even though several of these cell lines express relatively low levels of CD79b in vivo. In addition, we demonstrate that anti-CD79b ADCs were more effective than anti-CD79a ADCs and that, as hypothesized, anti-CD79b antibodies downregulated surface B-cell receptor and were trafficked to the lysosomal-like major histocompatibility complex class II-positive compartment MIIC. These results suggest that anti-CD79b-MCC-DM1 and anti-CD79b-MC-MMAF are promising therapeutics for the treatment of NHL.
    Full-text · Article · Aug 2007 · Blood