Microbiota and caspase-1/caspase-8 regulate IL-1β-mediated bone disease

Area of Science:

• Immunology
• Genetics
• Microbiology

Background:

• A specific mutation in the proline-serine-threonine phosphatase interacting protein 2 (PSTPIP2) gene causes autoinflammatory disease in mice (Pstpip2^cmo), characterized by splenomegaly, necrosis, and osteomyelitis.
• The disease progression in Pstpip2^cmo mice mirrors human chronic recurrent multifocal osteomyelitis.
• Previous research indicates that the cytokine IL-1β, independent of inflammasomes or IL-1α, drives disease progression in these mice.

Purpose of the Study:

• To review the current literature on the Pstpip2^cmo murine model of autoinflammatory osteomyelitis.
• To establish the clinical significance of PSTPIP2 in regulating this condition.
• To highlight the role of innate immune cell components in the disease.

Main Methods:

• Review of existing scientific literature on the Pstpip2^cmo mouse model.
• Analysis of the role of IL-1β in disease pathogenesis.
• Investigation into the impact of diet-induced changes in intestinal microbiota on disease development.

Main Results:

• Diet-induced alterations in intestinal microbiota confer protection against osteomyelitis development in Pstpip2^cmo mice.
• The proteases caspase-1 and caspase-8 play redundant roles in cleaving IL-1β, thereby promoting disease.
• IL-1β is a key mediator of disease progression, irrespective of inflammasome activation or IL-1α.

Conclusions:

• The Pstpip2^cmo mouse model is a valuable tool for studying autoinflammatory osteomyelitis.
• Intestinal microbiota composition significantly influences the development of osteomyelitis in this model.
• Targeting IL-1β cleavage by caspase proteases presents a potential therapeutic strategy for autoinflammatory osteomyelitis.