Antibody Class Switch (IMAGE) La Jolla Institute for Immunology Caption B cells need to do some genetic engineering before they make new classes of antibodies known as Immunoglobulins G or A (IgG or IgA). Credit La Jolla Institute for Immunology Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.