Multinucleate host cells induced by Vittaforma corneae (Microsporidia)

Area of Science:

• Cell Biology
• Parasitology
• Microbiology

Background:

• Microsporidia are obligate intracellular parasites.
• Vittaforma corneae is a microsporidian parasite known to infect host cells.

Purpose of the Study:

• To investigate the cellular mechanisms by which Vittaforma corneae induces structural changes in host cells.
• To characterize the host-parasite interactions and the formation of multinucleate structures.

Main Methods:

• Infection of green monkey kidney (E6) cells and various epithelial cell lines with V. corneae at different temperatures.
• Live cell imaging to observe parasite development and host cell dynamics.
• Immunocytochemistry to identify cytoskeletal components (gamma and alpha tubulin).
• Whole cell patch clamp analysis to measure membrane capacitance.
• Scanning electron microscopy to examine cell surface morphology.

Main Results:

• V. corneae infection of E6 cells at 30-37°C induced enlarged, multinucleate structures (up to 200 µm).
• These structures were formed by single or fused cells capable of mitosis, unlike differentiated epithelial cells.
• A single microtubule organizing center (MTOC) regulated the distribution of parasite stages and host mitochondria.
• Infected cells showed a five-fold increase in membrane capacitance, indicating significant cell enlargement.
• Scanning electron microscopy revealed cell-like protrusions and parasite-filled spaces.

Conclusions:

• V. corneae subverts the host cell cytoskeleton and cell volume regulation in E6 cells.
• The parasite creates a protected intracellular niche, analogous to a xenoma, for its development.
• Host cell mitotic capability is crucial for the formation of these parasite-induced structures.