Respiratory burst

Respiratory burst (also known as oxidative burst) is a metabolic process occurring in phagocytes which results in the rapid release of reactive oxygen species (ROS). This process is an essential part of the immune response, as it aids in the destruction of ingested pathogens.

Mechanism

The respiratory burst is initiated when a phagocyte engulfs a pathogen. This triggers the activation of an enzyme known as NADPH oxidase, which is located in the membrane of the phagocyte. NADPH oxidase then catalyzes the reduction of oxygen to superoxide, a reactive oxygen species. This superoxide can be further processed to form other ROS, such as hydrogen peroxide and hydroxyl radicals, which are toxic to pathogens.

Role in Immune Response

The ROS produced during the respiratory burst are crucial for the immune response. They are capable of damaging and killing pathogens, thus helping to clear infections. However, they can also cause tissue damage if produced in excess, leading to inflammatory diseases.

Clinical Significance

Defects in the respiratory burst can lead to immunodeficiency diseases, such as Chronic Granulomatous Disease (CGD). CGD is characterized by recurrent infections, as the phagocytes are unable to effectively kill ingested pathogens.

See Also

• Phagocytosis
• Reactive oxygen species
• Chronic Granulomatous Disease