NLRP12 provides a critical checkpoint for osteoclast differentiation

Area of Science:

• Immunology
• Bone Biology
• Cell Signaling

Background:

• The alternative nuclear factor kappa B (NF-κB) pathway is crucial for osteoclast (OC) function and bone metabolism.
• Nucleotide-binding leucine-rich repeat and pyrin domain-containing receptor 12 (NLRP12) is implicated in innate immunity, but its role in bone biology is unclear.

Purpose of the Study:

• To investigate the role of NLRP12 in regulating osteoclastogenesis and bone homeostasis.
• To determine if NLRP12 modulates the alternative NF-κB pathway in osteoclast precursors.

Main Methods:

• Retroviral overexpression and genetic ablation of NLRP12 in osteoclast precursors.
• In vitro studies of osteoclast differentiation and NF-κB signaling.
• In vivo studies using radiation chimeras and RANKL injection models.

Main Results:

• NLRP12 overexpression suppressed RelB nuclear translocation and osteoclast formation.
• NLRP12 deficiency promoted NIK stabilization, RelB nuclear translocation, and increased osteoclastogenesis.
• NLRP12-deficient mice exhibited increased OC numbers, decreased bone mass, and enhanced osteolytic responses.

Conclusions:

• NLRP12 plays a protective role in bone by suppressing alternative NF-κB-induced osteoclastogenesis.
• Modulation of NLRP12 levels impacts bone homeostasis and osteolytic responses by controlling NF-κB signaling in OC precursors.