Immunohistochemistry

thumb|230px|Main staining patterns on chromogenic immunohistochemistry. thumb|right|Immunofluorescence of human skin using an anti-IgA antibody. The skin is from a patient with [[Henoch–Schönlein purpura: IgA deposits are found in the walls of small superficial capillaries (yellow arrows). The pale wavy green area on top is the epidermis, the bottom fibrous area is the dermis.]] thumb|"Block" staining: strong nuclear and cytoplasmic expression in a continuous segment of cells. Immunohistochemistry is a form of immunostaining. It involves the process of selectively identifying antigens in cells