The Arthus reaction involves the in situ formation of antigen/antibody complexes after the intradermal injection of an antigen. If the individual has circulating antibody either from passive immunity or because of prior encounter with the antigen, an Arthus reaction may occur. Typical of most mechanisms of the type III hypersensitivity, Arthus manifests as local vasculitis due to deposition of IgG-based immune complexes in dermal blood vessels.
The Arthus response involves the in situ creation of antigen/antibody complexes following the intradermal injection of an antigen. If the individual possesses circulating antibody either from passive immunity or due to a prior encounter with the antigen, an Arthus reaction may occur. Typical of most mechanisms of type III hypersensitivity, Arthus manifests as local vasculitis resulting from deposition of IgG-based immune complexes in dermal blood vessels.