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[The effect of substances produced by a strain of Streptococcus sp. Thom-1606 on phagocytic activity]

V K Golshmid, N M Landsman, S Ia Savranskaia

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |January 1, 1995
    PubMed

    Insights

    Streptococcus sp. strain TOM-1606 produces two peptide fractions affecting macrophage phagocytosis. A low molecular weight fraction (≤10 kD) enhances phagocytosis and antimicrobial activity, while a high molecular weight fraction (70-100 kD) suppresses it.

    Area of Science:

    • Microbiology
    • Immunology
    • Biochemistry

    Background:

    • Streptococcus sp. strain TOM-1606 produces various substances.
    • Phagocytic activity of macrophages is crucial for immune response.
    • Understanding microbial immunomodulation is vital for therapeutic development.

    Purpose of the Study:

    • To investigate the immunomodulatory effects of substances produced by Streptococcus sp. strain TOM-1606 on macrophage phagocytosis.
    • To characterize the molecular weight and activity of these substances.

    Main Methods:

    • Extraction and fractionation of substances from Streptococcus sp. strain TOM-1606.
    • Assay of phagocytic activity of mouse peritoneal macrophages.
    • Determination of molecular weights of active fractions.

    Main Results:

    • Two distinct fractions with opposing effects on phagocytosis were identified.
    • A fraction ≤10 kD activated natural phagocytosis and exhibited antimicrobial activity.
    • A fraction of 70-100 kD inhibited natural phagocytosis, acting as an immunosuppressive agent.

    Conclusions:

    • Streptococcus sp. strain TOM-1606 produces peptides that differentially modulate macrophage phagocytosis.
    • Low molecular weight peptides (<10 kD) are immunostimulatory, while higher molecular weight peptides (70-100 kD) are immunosuppressive.
    • These findings suggest potential applications in modulating immune responses.

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