These receptors recognize conserved domains known as pathogen-associated molecular patterns, including flagellin, sugars, and the cell wall components of various microbes such as peptidoglycan and lipopolysaccharide (LPS) as well as danger-associated molecular patterns that are released by injured cells such as mammalian dsDNA and uric acid crystals.

The family of PRRs includes both membrane-bound receptors such as Toll like receptors (TLRs) and c-type lectin receptors, as well as cytoplasmic nod-like receptors (NLR). The innate immune system recognizes a wide range of pathogens such as viruses, bacteria, and fungi, by germline-encoded receptors known as pattern-recognition receptors (PRRs) ( 409). The four cardinal signs of localized acute inflammation described almost 2000 years ago by the Roman physician Celsus are as follows: Calor heat, Rubor redness, tumor swelling, and Dolor pain, leading to Functiolaesa loss (or impairment) of function. While this is considered advantageous to the organism, it can if unchecked also lead to inflammation and disease. The innate immune system on encountering pathogens elicits the acute inflammatory response that is accompanied by systemic vasodilation, vascular leakage, and leukocyte emigration ( 65). There are two complementary immune systems in vertebrates that recognize and eliminate pathogens: innate immune system and adaptive immune system ( 65). The immune system of vertebrates has evolved this survival strategy property to facilitate tissue repair.

I nflammation is a defensive immune response that is conferred by the host against foreign pathogens.

Sage act pro 2013 sp update