Egestion of degraded meningococci by polymorphonuclear leukocytes

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Updated: Oct 27, 2026

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature
11:40

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature

Published on: April 1, 2014

I W DeVoe

    Journal of Bacteriology
    |January 1, 1976
    PubMed

    Insights

    Mouse white blood cells (polymorphonuclear leukocytes) were observed to excrete contents after engulfing Neisseria meningitidis. This process involved membrane fusion and released bacterial products, not whole bacteria.

    Area of Science:

    • Immunology
    • Microbiology
    • Cell Biology

    Background:

    • Phagocytosis is a key immune process where cells engulf pathogens.
    • Neisseria meningitidis is a bacterium that can cause serious infections.
    • Polymorphonuclear leukocytes are crucial immune cells involved in bacterial clearance.

    Purpose of the Study:

    • To quantitatively investigate the in vitro phagocytosis of Neisseria meningitidis by mouse polymorphonuclear leukocytes.
    • To elucidate the mechanisms of bacterial product excretion following phagocytosis.

    Main Methods:

    • Quantitative analysis of in vitro phagocytosis using 14C-labeled Neisseria meningitidis.
    • Morphological observation of phagocytic vacuole and plasma membrane interactions.
    • Analysis of excreted bacterial products.

    Main Results:

    • Polymorphonuclear leukocytes excreted radioactive bacterial products into the supernatant.
    • Morphological studies showed fusion between phagocytic vacuoles and leukocyte plasma membranes.
    • Excreted materials consisted of membranous vesicles, free from intact bacteria.

    Conclusions:

    • Leukocytes can excrete degraded bacterial products after phagocytosis.
    • This excretion involves a process of exocytosis via membrane fusion.
    • The findings shed light on the fate of engulfed bacteria within immune cells.

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