Early Indus Valley Civilization ... their Geograhpy, their customs and Indo-Aryan civilization with the earliest caste system.
Antibodies contribute to immunity in three main ways: they can prevent pathogens from entering or damaging cells by binding to them; they can stimulate removal of a pathogen by macrophages and other cells by coating the pathogen; and they can trigger direct pathogen destruction by stimulating other immune responses such as the complement pathway.
Quick Answer. A specific type of white blood cell â the B lymphocytes â produce antibodies as part of the immune system. When lymphocytes detect the presence of a destructive substance â an antigen â the immune system reacts by forming antibodies. Each type of antibody is effective against one specific antigen.