Antibodies

 

  • 5 basic classes of Antibodies - IgM, IgG, IgA, IgD, IgE
IgM

large pentameric antibody secreted into blood in early steps of a primary B-cell response.

presence indicates any recent infection or some viruses' re-activation

activate the 1st component of complement and opsonize bacteria etc in phagocytosis
IgG

major antibody class

provides effective humoral primary and secondary response

have the longest life.

capable of complement activating and bacteria opsonizing.
IgA

serum IgA can neutralise various toxins and metabolites

secretory IgA (IgAs) is the principal antibody class in secreted saliva, tears, milk, respiratory, intestinal and genital secretions.

exists in the dimeric form
IgD almost exclusively found inserted into the membranes of B cells, where it somehow regulates the cell's activation
IgE

cytophilic immunoglobulin in relation to mast cells/basophils

plays a crucial role in type I hypersensitivity or atopy, e.g. in bronchial asthma, allergic rhinitis, atopic dermatitis etc