<unk>  diseases An<unk> , sometimes called an antigen-antibody<unk>  or antigen-bound antibody, is a molecule formed from the binding of multiple antigens to antibodies. The bound antigen and antibody act as a unitary object, effectively an antigen of its own with a specific epitope. After an antigen-antibody reaction, the<unk> es can be subject to any of a number of responses, including<unk> ent deposition, opsonization, phagocytosis, or processing by proteases. Red blood cells carrying CR1-receptors on their surface may bind C3b-coated<unk> es and transport them to phagocytes, mostly in liver and spleen, and return to the general circulation. The ratio of antigen to antibody determines size and shape of<unk> . This, in turn, determines the effect of the<unk> . Many innate<unk>  cells have FcRs, which are membrane-bound receptors that bind the constant regions of antibodies. Most FcRs on innate<unk>  cells have low affinity for a singular antibody, and instead need to bind to an<unk>  containing multiple antibodies in order to begin their intracellular signaling pathway and pass along a message from outside to inside of the cell. Additionally, the grouping and binding together of multiple<unk> es allows for an increase in the avidity, or strength of binding, of the FcRs. This allows innate<unk>  cells to get multiple inputs at once and prevents them from being activated early.<unk> es may themselves cause illness when they are deposited in organs, for example, in certain forms of vasculitis. This is the third form of hypersensitivity in the Gell-Coombs classification, called type III hypersensitivity. Such hypersensitivity progressing to disease states produces the<unk>  diseases.<unk>  deposition is a prominent feature of several autoimmune diseases, including rheumatoid arthritis, scleroderma and Sjögren's syndrome. An inability to degrade<unk> es in the lysosome and subsequent accumulation on the surface of<unk>  cells has been associated with systemic lupus erythematosus.
Immune complex
Heterophile antibody
Microantibody
Antibody
Autoantibody
Isoantibodies
Protein corona
Therapeutic interfering particle