antibodies

IgG

provides long term protection, most abundant antibody in the body, activates complement system, crosses the placenta and provides temporary immunity to fetus

IgM

first antibody produced in a primary immune response, good at agglutination (clumping pathogens)

IgA

protects mucosal surfaces (respiratory, GI, urogenital tracts) found in secretions - saliva tears mucus breast milk, and prevents pathogen attachment

first-line defense at body surfaces

IgE

Involved in allergic reactions — binds to mast cells and basophils to trigger histamine release - responsible for hypersensitivity to allergies

IgD

acts as a B cell receptor, functions in activation of B cells