Antibody

Antibodies are large glycoproteins that help protect the body against infection. They bind with a high degree of specificity to molecular structures (antigens) on infectious agents. This can lead to enhanced killing of microbes by phagocytes or complement.

They can be segregated into 5 classes; IgG, IgM, IgE, IgA and IgD. Each of them has different distribution in the body. IgM and IgA are multimeric. The other three are monomeric antibodies. IgA exist as both multimeric and monomeric antibody in different tissues of the body.