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Published on: September 15, 2017

PRODUCTION OF INFLAMMATORY CHANGES IN THE MICROCIRCULATION BY CATIONIC PROTEINS EXTRACTED FROM LYSOSOMES

A JANOFF, B W ZWEIFACH

    The Journal of Experimental Medicine
    |November 1, 1964
    PubMed

    Insights

    Lysosomal cationic proteins from polymorphonuclear (PMN) leucocytes trigger key inflammatory responses, including leucocyte adhesion and emigration. These findings highlight the role of lysosomes in tissue injury and inflammation propagation.

    Area of Science:

    • Biochemistry
    • Immunology
    • Cell Biology

    Background:

    • Lysosomes within polymorphonuclear (PMN) leucocytes contain potent mediators.
    • The role of specific lysosomal components in initiating inflammatory responses requires further elucidation.

    Purpose of the Study:

    • To investigate the inflammatory potential of cationic proteins isolated from rabbit PMN leucocyte lysosomes.
    • To characterize the specific components responsible for leucocyte adhesion and emigration.

    Main Methods:

    • Isolation and lysis of lysosomal granules from rabbit PMN leucocytes.
    • Topical application of isolated fractions to rat and rabbit mesentery.
    • Biochemical analysis including ethanol precipitation, electrophoresis, and enzyme assays.
    • In vitro platelet aggregation and mitochondrial swelling assays.

    Main Results:

    • A 20% ethanol-precipitated cationic protein fraction induced leucocyte sticking, emigration, stasis, and hemorrhage.
    • This active fraction demonstrated greater inflammatory intensity than lysed whole granules.
    • The active fraction caused platelet clumping in vitro and transient vasodepression in rats.

    Conclusions:

    • Specific cationic proteins from PMN leucocyte lysosomes are potent inducers of leucocyte emigration and microcirculatory injury.
    • Lysosomes play a critical role in the pathogenesis of inflammation and tissue damage.
    • These findings provide a molecular basis for understanding leucocyte recruitment in inflammatory reactions.
    Keywords:
    BRADYKININCAPILLARY PERMEABILITYEXPERIMENTAL LAB STUDYEXUDATES AND TRANSUDATESHISTAMINEINFLAMMATIONLEUKOCYTESLYSOSOMESMESENTERYMITOCHONDRIAMUSCLE, SMOOTHNEUTROPHILSNOREPINEPHRINEPHARMACOLOGYPROMETHAZINEPROTEINSRABBITSRATSRIBONUCLEASETOXICOLOGIC REPORT

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