Isolated colony, identity unknown Antibodies of known identity ANTISERUM Macroscopic reaction Molecular reaction Ag on microbe Ab

An immune response is the type of antibody production and activates in response to foreign antigen. In type III hypersensitivity, excessive production of immunoglobin IgG and IgM to a foreign or self‐antigen can lead to the development and accumulation of extreme amounts of insoluble intermediate‐sized immune complexes, which can be challenging to remove from various tissues by phagocytosis. This in turn may further, activate classical complement activation, leading to excessive production of other inflammatory mediators, activation and degranulation of peripheral blood granulocytes, such as basophils or an influx of neutrophils to particular tissues, such as the kidneys, lungs and joints culminating in damage. 

Group A streptococci are extracellular bacterial pathogens that cause a variety of pyogenic infections affecting the mucous membranes, tonsils, skin, and deeper tissues, including, pneumonia, and meningitis. Infections could be mild to severe and may include multiple complications and even death.

Treatment of streptococcal toxic shock syndrome is possible with intravenous immunoglobulin (IVIG)that decreases the death rate. The reason could be that IVIG produces neutralizing antibodies. All three streptococcal pyrogenic exotoxins, A, B, and C, were inhibited by the IVIG.