Fc-engineering significantly improves the recruitment of immune effector cells by anti-ICAM-1 antibody MSH-TP15 for myeloma therapy.

Fc-engineering significantly improves the recruitment of immune effector cells by anti-ICAM-1 antibody MSH-TP15 for myeloma therapy. Haematologica. 2020 Jun 04;: Authors: Klausz K, Cieker M, Kellner C, Rösner T, Otte A, Krohn S, Lux A, Nimmerjahn F, Valerius T, Gramatzki M, Peipp M Abstract Despite several therapeutic advances, patients with multiple myeloma (MM) require additional treatment options since no curative therapy exists yet. In search of a novel therapeutic antibody, we previously applied phage display with myeloma cell screening and developed TP15, a scFv targeting intercellular adhesion molecule 1 (ICAM-1/CD54). To more precisely evaluate the antibody's modes of action, fully human IgG1 antibody variants were generated bearing wild-type (MSH-TP15) or mutated Fc to either enhance (MSH-TP15 Fc-eng.) or prevent (MSH-TP15 Fc k.o.) Fc gamma receptor binding. Especially MSH-TP15 Fc-eng. induced potent antibody-dependent cell-mediated cytotoxicity (ADCC) against malignant plasma cells by efficiently recruiting NK cells and engaged macrophages for antibody-dependent cellular phagocytosis (ADCP) of tumor cells. Binding studies with truncated ICAM-1 demonstrated MSH-TP15 binding to ICAM-1 domain 1-2. Importantly, MSH-TP15 and MSH-TP15 Fc-eng. both prevented myeloma cell engraftment and significantly prolonged survival of mice in an intraperitoneal xenograft model. In the subcutaneous model MSH-TP15 Fc-eng. was superior to MSH-TP...
Source: Haematologica - Category: Hematology Authors: Tags: Haematologica Source Type: research