IGG stands for Immunoglobulin G, which is a type of antibody found in the blood and other bodily fluids. It plays a crucial role in the immune system by identifying and neutralizing pathogens like bacteria and viruses. IGG is the most abundant antibody in the body, making up about 75% of the immunoglobulins present in the bloodstream. IGG is produced by B cells, a type of white blood cell, in response to infections or vaccinations. It helps provide long-term immunity by remembering past infections, allowing the body to respond more effectively if the same pathogen is encountered again.