Leptospiral attachment to cultured cells.

Area of Science:

• Microbiology
• Cell Biology
• Immunology

Background:

• Leptospira interrogans are pathogenic bacteria responsible for leptospirosis.
• Understanding bacterial attachment to host cells is crucial for pathogenesis.
• Differential virulence exists among Leptospira serovars.

Purpose of the Study:

• To investigate the attachment capabilities of different Leptospira interrogans serovars to mammalian kidney cells.
• To explore the role of host-pathogen interactions in Leptospira attachment.
• To identify potential mechanisms inhibiting the attachment of virulent Leptospira strains.

Main Methods:

• In vitro cell culture using MDCK cells and primary dog kidney cells.
• Inoculation with virulent and avirulent strains of Leptospira interrogans (serovars copenhageni, canicola, pomona) and Leptospira biflexa.
• Inhibition assays using homologous immunoglobulin G Fab fragments.

Main Results:

• Virulent Leptospira interrogans strains (copenhageni, canicola, pomona) demonstrated effective attachment to kidney cells.
• Avirulent strains of L. interrogans and reference strains of other serovars showed significantly less or no attachment.
• Attachment of virulent L. interrogans copenhageni to MDCK cells was inhibited by homologous immunoglobulin G Fab fragments.
• Leptospira biflexa strains attached to animal cells but exhibited different glass attachment capabilities compared to virulent L. interrogans.

Conclusions:

• Virulence in Leptospira interrogans correlates with effective attachment to host kidney cells.
• Specific interactions, potentially mediated by surface structures, facilitate virulent Leptospira attachment.
• Immunoglobulin G Fab fragments can interfere with virulent Leptospira attachment, indicating a target for therapeutic intervention.