A novel bispecific protein (ULBP2-BB4) targeting the NKG2D receptor on natural killer (NK) cells and CD138 activates NK cells and has potent antitumor activity against human multiple myeloma in vitro and in vivo.
The inability of the immune system to recognize and kill malignant plasma cells in patients with multiple myeloma (MM) has been attributed in part to the ineffective activation of natural killer (NK) cells. In order to activate and target NK cells to the malignant cells in MM we designed a novel recombinant bispecific protein (ULBP2-BB4). While ULBP2 binds the activating NK receptor NKG2D, the BB4 moiety binds to CD138, which is overexpressed on a variety of malignancies, including MM. ULBP2-BB4 strongly activated primary NK cells as demonstrated by a significant increase in interferon-gamma (IFN-gamma) secretion. In vitro, ULBP2-BB4 enhanced the NK-mediated lysis of 2 CD138+ human MM cell lines, U-266 and RPMI-8226, and of primary malignant plasma cells in the allogenic and autologous setting. Moreover, in a nude mouse model with subcutaneously growing RPMI-8226 cells, the cotherapy with ULBP-BB4 and human peripheral blood lymphocytes abrogated the tumor growth. These data suggest potential clinical use of this novel construct in patients with MM. The use of recombinant NK receptor ligands that target NK cells to tumor cells might offer new approaches for other malignancies provided a tumor antigen-specific antibody is available.
von Strandmann
Elke Pogge
EP
Laboratory of Immunotherapy, Department I for Internal Medicine, University Hospital of Cologne, Kerpener Str 62, D-50924 Köln, Germany. e.pogge@uni-koeln.de
Hansen
Hinrich P
HP
Reiners
Katrin S
KS
Schnell
Roland
R
Borchmann
Peter
P
Merkert
Sabine
S
Simhadri
Venkateswara R
VR
Draube
Andreas
A
Reiser
Marcel
M
Purr
Ingvill
I
Hallek
Michael
M
Engert
Andreas
A
D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics / Q000276:immunology / Q000494:pharmacology*; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000276:immunology / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002522:Chlorocebus aethiops; D016503:Drug Delivery Systems / Q000379:methods; D058851:GPI-Linked Proteins; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology / Q000494:pharmacology*; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology / Q000494:pharmacology*; D036341:Intercellular Signaling Peptides and Proteins; D007694:Killer Cells, Natural / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology; D008562:Membrane Glycoproteins / Q000276:immunology; D051379:Mice; D008819:Mice, Nude; D009101:Multiple Myeloma / Q000188:drug therapy* / Q000276:immunology; D055655:NK Cell Lectin-Like Receptor Subfamily K; D009368:Neoplasm Transplantation; D011509:Proteoglycans / Q000276:immunology; D011971:Receptors, Immunologic / Q000276:immunology; D055607:Receptors, Natural Killer Cell; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D053668:Syndecan-1; D053667:Syndecans
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D058851:GPI-Linked Proteins; D015395:Histocompatibility Antigens Class I; D007135:Immunoglobulin Variable Region; D036341:Intercellular Signaling Peptides and Proteins; C527085:KLRK1 protein, human; C527086:Klrk1 protein, mouse; D008562:Membrane Glycoproteins; D055655:NK Cell Lectin-Like Receptor Subfamily K; D011509:Proteoglycans; D011971:Receptors, Immunologic; D055607:Receptors, Natural Killer Cell; D011993:Recombinant Fusion Proteins; C508241:SDC1 protein, human; C508242:Sdc1 protein, mouse; D053668:Syndecan-1; D053667:Syndecans; C423230:ULBP2 protein, human