Laboratory discovers new antibody function

The international consortium led by Ambati found that the most abundant class of antibodies, known as IgG1s, also generically block blood vessel growth, an unexpected finding with far-reaching implications. Therapeutic human antibodies, most of which are IgG1s and account for more $75 billion in annual sales worldwide, are commonly used to treat various diseases such as arthritis, psoriasis, inflammatory bowel disease, leukemia and asthma.
Ambati's laboratory found that FDA-approved and widely used monoclonal antibodies such as Humira, Campath, Lemtrada, Arzerra, Xolair, Synagis, Actemra, and Avastin could inhibit blood vessel growth independent of their intended targets. Moreover, the researchers also showed that intravenous immunoglobulin (IVIG), a low-cost mixture of human antibodies used to treat many autoimmune diseases, also blocked blood vessel growth.
These two groundbreaking studies used not only preclinical models of macular degeneration, peripheral arterial disease, colon cancer, but also verified the clinical relevance of their findings by examining biopsied tissue from organ transplant patients before and after IVIg therapy.
"Given the widespread use of monoclonal antibodies for many diseases, both in the eye and beyond, these findings have broad clinical implications," said Ambati.