Novel Antibody Clone for Targeting Multiple Myeloma Cancer Cells
Scientists at Osaka University in Japan have identified an anti–multiple myeloma monoclonal antibody, MMG49, as a new target for treatment of patients with multiple myeloma, according to new research published in Nature Medicine. By searching for cancer-specific monoclonal antibodies and characterizing the recognized antigens, lead author Naoki Hosen, PhD, of the Department of Cancer Stem Cell Biology, Osaka University Graduate School of Medicine, and colleagues may have discovered a new target for managing multiple myeloma.
By screening 10,000 antibody clones, the researchers found MMG49 recognized a subset of integrin β7, a cell-surface receptor that facilitates cell-extracellular matrix adhesion. The team used MMG49 to stain bone marrow cells from patients with multiple myeloma. MMG49 exhibited distinct binding to cancer cells but “negligible” binding to normal leukocytes or noncancer cells in 45 of 51 samples. The researchers then designed a chimeric antigen receptor (CAR) that used fragments of MMG49, which was found to have anti–multiple myeloma effects without damaging normal blood cells.
Because MMG49 was hardly detectable in other cell types, including normal integrin β7-positive lymphocytes, the researchers see MMG49 CAR T-cell therapy as a promising type of treatment requiring further investigation.
“We found that the activated integrin β7 serves as a specific target for CAR T-cell therapy against multiple myeloma,” Dr. Hosen told OncoTherapy Network. “It will be tested in a clinical trial in 2 years.”