The epithelioid cell is a modified-
Granulomatous inflammation is a form of chronic inflammation characterized by collections of activated macrophages. often with T lymphocytes, and sometimes associated with central necrosis.
These granulomas are type IV hypersensitivity reaction that involves CD4-helper T-ceIIs.
Helper T-cells are activated by IL-2 and produce IFN-γ (interferon gamma) the major cytokine of granulomatous inflammation.

□ IFN-γ induces the formation of granuloma by conversion of activated macrophages into epithelioid cells and the formation of giant cells by fusion of epithelial cells,
Macrophage
Lymphocyte
Mast cell
Eosinophil