Inflammasome-independent IL-1β mediates autoinflammatory disease in Pstpip2-deficient mice

SL Cassel, JR Janczy, X Bing… - Proceedings of the …, 2014 - National Acad Sciences
SL Cassel, JR Janczy, X Bing, SP Wilson, AK Olivier, JE Otero, Y Iwakura…
Proceedings of the National Academy of Sciences, 2014National Acad Sciences
Chronic recurrent multifocal osteomyelitis (CRMO) is a human autoinflammatory disorder
that primarily affects bone. Missense mutation (L98P) of proline-serine-threonine
phosphatase-interacting protein 2 (Pstpip2) in mice leads to a disease that is phenotypically
similar to CRMO called chronic multifocal osteomyelitis (cmo). Here we show that deficiency
of IL-1RI in cmo mice resulted in a significant reduction in the time to onset of disease as
well as the degree of bone pathology. Additionally, the proinflammatory cytokine IL-1β, but …
Chronic recurrent multifocal osteomyelitis (CRMO) is a human autoinflammatory disorder that primarily affects bone. Missense mutation (L98P) of proline-serine-threonine phosphatase-interacting protein 2 (Pstpip2) in mice leads to a disease that is phenotypically similar to CRMO called chronic multifocal osteomyelitis (cmo). Here we show that deficiency of IL-1RI in cmo mice resulted in a significant reduction in the time to onset of disease as well as the degree of bone pathology. Additionally, the proinflammatory cytokine IL-1β, but not IL-1α, played a critical role in the pathology observed in cmo mice. In contrast, disease in cmo mice was found to be independent of the nucleotide-binding domain, leucine-rich repeat-containing family, pyrin domain-containing 3 (NLRP3) inflammasome as well as caspase-1. Neutrophils, but not bone marrow-derived macrophages, from cmo mice secreted increased IL-1β in response to ATP, silica, and Pseudomonas aeruginosa compared with neutrophils from WT mice. This aberrant neutrophil response was sensitive to inhibition by serine protease inhibitors. These results demonstrate an inflammasome-independent role for IL-1β in disease progression of cmo and implicate neutrophils and neutrophil serine proteases in disease pathogenesis. These data provide a rationale for directly targeting IL-1RI or IL-1β as a therapeutic strategy in CRMO.
National Acad Sciences