Antibody therapies that target human B cells are a promising way to treat diseases like B-cell cancers and autoimmune conditions like lupus and multiple sclerosis. Traditionally, these antibodies are made in animals and modified to resemble human antibodies to reduce immune rejection. Researchers in the Laboratory of Immunoregulation (LIR) at the National Institute of Allergy and Infectious Diseases (NIAID) have developed a new approach of using blood plasma from a patient with the rare immune disorder idiopathic CD4 lymphocytopenia (ICL) to find naturally occurring human antibodies.

       By using advanced genetic sequencing, the researchers discovered and reproduced several new antibodies that could effectively attack and kill B-cell tumors, normal B cells, and T cells, demonstrating potential for eliminating cancerous or disease-causing immune cells. One potent antibody, NIH58.9, killed B cells at low concentrations of 0.01 nanomolar. These new antibodies may be used as treatments, combined with other therapies, or engineered into special formats like bispecific antibodies or antibody-drug conjugates.