Endogenous innate sensor NLRP3 is a key component in peritoneal macrophage dynamics required for cestode...

Area of Science:

• Immunology
• Infectious Diseases
• Parasitology

Background:

• The NLRP3 inflammasome is primarily known for triggering inflammatory responses.
• Emerging evidence indicates NLRP3 may also possess anti-inflammatory functions.
• Taenia crassiceps infection requires Th2 immune polarization and suppressive macrophages for parasite survival.

Purpose of the Study:

• To investigate the role of nucleotide-binding oligomerization domain pyrin-containing protein 3 (NLRP3) in experimental Taenia crassiceps infection.
• To understand how NLRP3 deficiency impacts host resistance and immune cell populations during infection.

Main Methods:

• Utilized NLRP3-deficient (NLRP3-/-) and wild-type (WT) mice in a Taenia crassiceps infection model.
• Assessed parasite resistance, cytokine profiles (IL-4, IL-15), and macrophage populations (suppressive macrophages).
• Performed transcriptional analysis on bone marrow-derived macrophages and evaluated the effect of microbiota exchange.

Main Results:

• NLRP3-/- mice exhibited significantly higher resistance to T. crassiceps compared to WT mice.
• Resistance in NLRP3-/- mice was linked to reduced IL-4, elevated IL-15, and fewer suppressive peritoneal macrophages.
• NLRP3-/- macrophages showed decreased expression of alternative activation and suppressive markers (relm-α, PD-1 ligands).
• Intestinal microbiota transfer from NLRP3-/- mice conferred resistance to WT mice.

Conclusions:

• NLRP3 is essential for Taenia crassiceps establishment, likely by facilitating macrophage recruitment and modulating IL-15.
• NLRP3 deficiency promotes resistance through altered immune cell function and cytokine balance.
• Host microbiota plays a role in NLRP3-mediated susceptibility or resistance to T. crassiceps infection.