neutrophil-mediated killing of fungus

Definition

Target type: biologicalprocess

The directed killing of a fungal cell by a neutrophil. [GOC:add, ISBN:0781765196]

Neutrophils, a type of white blood cell, are essential for the innate immune response against fungal infections. They employ a multifaceted arsenal of mechanisms to eliminate fungal invaders.

**1. Phagocytosis:** Neutrophils recognize and engulf fungal cells through pattern recognition receptors (PRRs) like Toll-like receptors (TLRs) and C-type lectin receptors (CLRs) that bind to fungal cell wall components such as chitin, glucans, and mannoproteins.

**2. Neutrophil Extracellular Traps (NETs):** Neutrophils can release NETs, a web-like structure composed of DNA, histones, and antimicrobial proteins. These NETs trap fungi, preventing their spread and facilitating their destruction.

**3. Oxidative Burst and Reactive Oxygen Species (ROS):** Upon encountering fungi, neutrophils undergo an oxidative burst, generating ROS like superoxide, hydrogen peroxide, and hypochlorous acid. These ROS damage fungal cell walls, membranes, and DNA, contributing to their death.

**4. Antimicrobial Peptides (AMPs):** Neutrophils release AMPs such as defensins and cathelicidins, which directly kill fungi by disrupting their cell membranes or interfering with essential metabolic processes.

**5. Degranulation:** Neutrophils release granules containing a variety of enzymes and antimicrobial proteins, including myeloperoxidase (MPO), elastase, and cathepsin G. These enzymes contribute to fungal cell lysis and degradation.

**6. Cytokine and Chemokine Production:** Neutrophils produce cytokines and chemokines that recruit other immune cells, such as macrophages and lymphocytes, to the site of infection. These cytokines also contribute to the inflammatory response, which helps to contain the fungal infection.

**7. Cooperation with Other Immune Cells:** Neutrophils collaborate with other immune cells, such as macrophages and dendritic cells, to enhance fungal killing and antigen presentation. This collaboration contributes to a more robust and specific immune response.

**8. Fungal Pathogen Specific Mechanisms:** The specific mechanisms of neutrophil-mediated fungal killing can vary depending on the fungal species. Some fungi, such as Candida albicans, can evade neutrophil killing by forming biofilms or switching to a yeast-like morphology. Other fungi, like Aspergillus fumigatus, produce melanin, which protects them from ROS and antimicrobial peptides.

**In summary, neutrophils utilize a diverse array of mechanisms, including phagocytosis, NET formation, ROS production, AMPs, degranulation, and cytokine production, to effectively target and eliminate fungal pathogens.**
'"

Proteins (1)

Compounds (83)