Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Immune Surveillance by NK Cells and Phagocytes01:25

Immune Surveillance by NK Cells and Phagocytes

Immune surveillance is an integral part of the innate immune system, involving the continuous monitoring of peripheral tissues to detect and respond to pathogens, infected cells, or cancerous cells. This surveillance is conducted primarily by natural killer (NK) cells and phagocytes, which employ distinct but complementary mechanisms to identify and eliminate threats.
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...
Lytic Cycle of Bacteriophages01:30

Lytic Cycle of Bacteriophages

Bacteriophages, also known as phages, are specialized viruses that infect bacteria. A key characteristic of phages is their distinctive “head-tail” morphology. A phage begins the infection process (i.e., lytic cycle) by attaching to the outside of a bacterial cell. Attachment is accomplished via proteins in the phage tail that bind to specific receptor proteins on the outer surface of the bacterium. The tail injects the phage’s DNA genome into the bacterial cytoplasm. In the lytic replication...
Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or  immature dendritic cells. Non-professional phagocytes such as  epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes. 
Normal cells contain receptors that prevent them from being recognized by phagocytes.
Bacteriophages of the Human Virome01:23

Bacteriophages of the Human Virome

Bacteriophages are found throughout the human body. They may even outnumber eukaryotic viruses, forming an important and dynamic component of the human virome. Indeed, phages represent the most abundant viral entities, with densities in the gut reaching up to 10⁹ particles per gram of fecal matter, and many belonging to orders such as Caudovirales and Microviridae, while a substantial proportion remains unclassified as viral “dark matter.”Lysogeny and Genetic ExchangeIn the gut, bacteriophages...
Cells of the Innate Immune Response01:28

Cells of the Innate Immune Response

The innate immune response is an immediate and non-specific response against pathogens, acting swiftly to prevent the spread of infections. The primary cells involved in this response are phagocytes and natural killer (NK) cells.
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Evaluation of Collagenase Activity from Crab Hepatopancreas in Different Model Systems.

Bulletin of experimental biology and medicine·2024
Same author

[Markers of redox potential of blood leukocytes in acute coronary syndrome, depending on the presence of type 2 diabetes mellitus].

Kardiologiia·2023
Same author

[Aortic stiffness and content of adipokines in the serum in persons of European and South Asian ethnic].

Terapevticheskii arkhiv·2022
Same author

Antihistamines Modulate Functional Activity of Macrophages.

Bulletin of experimental biology and medicine·2021
Same author

Effect of Mild Traumatic Brain Injury on Behavioral Reactions and Neocortical Morphology in Rats.

Bulletin of experimental biology and medicine·2021
Same author

Functional State of Mesenchymal Stem Cells upon Exposure to Bioactive Coatings on Titanium Alloys.

Bulletin of experimental biology and medicine·2020

Related Experiment Video

Updated: Jul 18, 2026

Measuring Phagosome pH by Ratiometric Fluorescence Microscopy
14:39

Measuring Phagosome pH by Ratiometric Fluorescence Microscopy

Published on: December 7, 2015

[Bactericidal activity of phagocytes].

N G Plekhova

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |December 14, 2006
    PubMed
    Summary

    This review explores how phagocytic cells use oxygen-dependent mechanisms to fight infections. It focuses on reactive oxygen metabolites and their role in killing microbes and signaling during inflammation. The study compares the functions of neutrophils and macrophages, highlighting differences in how they generate and use these metabolites. The review also discusses the extracellular release of low-molecular-weight substances by neutrophils, which may help coordinate immune responses. The findings suggest that these metabolites have multiple roles in host defense and inflammation.

    Keywords:
    phagocytic cellreactive oxygenhost defenseimmunology

    Frequently Asked Questions

    More Related Videos

    Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages
    10:33

    Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

    Published on: October 25, 2017

    Alveolar Macrophage Phagocytosis and Bacteria Clearance in Mice
    11:20

    Alveolar Macrophage Phagocytosis and Bacteria Clearance in Mice

    Published on: March 2, 2019

    Related Experiment Videos

    Last Updated: Jul 18, 2026

    Measuring Phagosome pH by Ratiometric Fluorescence Microscopy
    14:39

    Measuring Phagosome pH by Ratiometric Fluorescence Microscopy

    Published on: December 7, 2015

    Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages
    10:33

    Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

    Published on: October 25, 2017

    Alveolar Macrophage Phagocytosis and Bacteria Clearance in Mice
    11:20

    Alveolar Macrophage Phagocytosis and Bacteria Clearance in Mice

    Published on: March 2, 2019

    Area of Science:

    • Immunology
    • Infectious disease research
    • Cellular metabolism

    Background:

    The immune system relies on phagocytic cells to combat pathogens, yet the precise mechanisms remain unclear. Prior research has shown that reactive oxygen species play a role in microbial killing. However, the specific pathways and enzymes involved are not fully understood. This gap motivated further investigation into how phagocytes generate and utilize these metabolites. No prior work had resolved the differences in function between neutrophils and macrophages. The role of low-molecular-weight substances in phagocyte cooperation remains uncertain. This uncertainty highlights the need for a detailed review of current findings. This review aims to clarify these mechanisms and their broader implications in host defense.

    Purpose Of The Study:

    The purpose of this review is to evaluate the oxygen-dependent mechanisms of host defense by phagocytic cells. The study focuses on reactive oxygen metabolites and their enzymic systems. It seeks to clarify how these metabolites contribute to bactericidal activity. The review also explores the physiological roles of these metabolites beyond microbial killing. The specific problem addressed is the lack of consensus on how neutrophils and macrophages differ in function. The motivation stems from gaps in understanding phagocyte cooperation during infections. This work aims to synthesize recent findings to guide future research. The study emphasizes the need for a comprehensive overview of current evidence.

    Main Methods:

    The review approach involved analyzing recent literature on phagocytic cell function. The authors focused on oxygen-dependent mechanisms and enzymic systems. They examined the formation of reactive oxygen metabolites in detail. The study also compared the bactericidal activity of neutrophils and macrophages. Information on low-molecular-weight substances was included. The authors described the physiological roles of reactive metabolites. They analyzed how these substances influence inflammation and immunity. The review synthesized findings to highlight current understanding and unresolved questions.

    Main Results:

    The review highlights the role of reactive oxygen metabolites in microbial killing by phagocytes. These metabolites are generated through enzymic systems like NADPH oxidase. The study notes differences in bactericidal activity between neutrophils and macrophages. Neutrophils were found to release low-molecular-weight substances extracellularly. These substances may contribute to phagocyte cooperation during infections. The review also discusses the role of reactive metabolites as signaling molecules. Their function in inflammation and immune response is emphasized. The findings suggest that these metabolites have multiple physiological roles.

    Conclusions:

    The review concludes that reactive oxygen metabolites are central to phagocytic defense. The authors propose that these metabolites serve both bactericidal and signaling functions. Differences in activity between neutrophils and macrophages were noted. The extracellular release of low-molecular-weight substances was highlighted. The study suggests that these substances may enhance phagocyte cooperation. The role of reactive metabolites in inflammation is emphasized. The authors suggest that further research is needed to clarify these mechanisms. The findings provide a foundation for future studies on phagocyte function.

    Reactive oxygen metabolites contribute to microbial killing and act as signaling molecules in inflammation.

    Neutrophils release low-molecular-weight substances extracellularly, while macrophages may differ in their enzymic systems.

    NADPH oxidase generates reactive oxygen metabolites, which are essential for microbial killing.

    Reactive metabolites act as physiologic messengers, influencing immune responses and inflammation.

    These substances are bioactive and may enhance phagocyte cooperation during infections.

    The findings suggest a need to explore phagocyte cooperation and the physiological roles of reactive metabolites.