IMMUNOLOGY

Detailed explanation-1: -At the tissue level, inflammation is characterized by redness, swelling, heat, pain, and loss of tissue function, which result from local immune, vascular and inflammatory cell responses to infection or injury [5].

Detailed explanation-2: -When a pathogen invades a tissue, it almost always elicits an inflammatory response. This response is characterized by pain, redness, heat, and swelling at the site of infection, all caused by changes in local blood vessels.

Detailed explanation-3: -Classical features of inflammation are heat, redness, swelling and pain. Inflammation can be part of the normal host response to infection and a required process to rid the body of pathogens, or it may become uncontrolled and lead to chronic inflammatory disease.