ICT (Information Communications Technology) is a term widely used in the context of education. Even though there is no universally accepted definition for ICT, it mainly refers to utilizing digital technologies such as computers, television, email, etc to help individuals or organizations to use information.
Type IV (called also delayed hypersensitivity) involves sensitized T lymphocytes that react with cell bound or associated antigen and release lymphokines, causing mononuclear cell accumulation, tissue damage and inflammation, typically manifesting at least 24 hours after exposure to the antigen.
Presentation [edit]. Type III hypersensitivity occurs when there is an excess of antigen, leading to small immune complexes being formed that do not fix complement and are not cleared from the circulation. It involves soluble antigens that are not bound to cell surfaces (as opposed to those in type II hypersensitivity).When these antigens bind antibodies, immune complexes of different sizes form. Large complexes can be cleared by macrophages but macrophages have difficulty in the disposal of small immune complexes.These immune complexes insert themselves into small blood vessels, joints, and glomeruli, causing symptoms.hen these antigens bind antibodies, immune complexes of different sizes form. Large complexes can be cleared by macrophages but macrophages have difficulty in the disposal of small immune complexes. These immune complexes insert themselves into small blood vessels, joints, and glomeruli, causing symptoms.