Immunopathogenesis is the research field that investigates the mechanisms by which immune system components and processes contribute to the development and progression of disease in host tissues. This involves analyzing the complex interplay of immune cells, mediators, and target organs, focusing on how immune activation, dysregulation, or failed tolerance leads to tissue injury, functional impairment, and clinical pathology in conditions such as infections, autoimmunity, allergy, and chronic inflammation. Understanding these processes is fundamental for diagnosing, preventing, and treating immune-mediated diseases.