International Journal of Medical Laboratory Research (IJMLR)

INVESTIGATING HOW NEUTROPHILS CONTRIBUTE TO THE BODY'S DEFENSE AGAINST INFECTIONS

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Fahmia Feroz, Sawaira Parvaiz

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ABSTRACT:

Neutrophils are essential effector cells of the innate immune system and act as the first line of defense against microbial invaders. At sites of infection, they deploy multiple protective strategies, including phagocytosis, degranulation, production of antimicrobial peptides, and the release of neutrophil extracellular traps (NETs) to capture and neutralize pathogens. While these functions are crucial for host defense, excessive or dysregulated activation can cause tissue injury, chronic inflammation, and immunopathology. This review highlights the multifaceted roles of neutrophils in pathogen clearance, immune regulation, and resolution of inflammation, while also examining how their dysfunction contributes to infectious diseases, autoimmune disorders, and sepsis. Understanding the delicate balance of neutrophil activity offers valuable insights into therapeutic strategies aimed at enhancing host defense while minimizing tissue damage.

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Keywords: Neutrophils, Innate immunity, Host defense, Infection, Phagocytosis, NETs, Antimicrobial peptides, Immune regulation, Inflammation, Pathogen clearance, Immune dysfunction, Autoimmunity, Sepsis, Chronic inflammation

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