NF-κB/MAPK activation underlies ACVR1-mediated inflammation in human heterotopic ossification.

Background: Inflammation helps regulate normal growth and tissue repair. Although bone morphogenetic proteins (BMPs) and inflammation are known contributors to abnormal bone formation, how these pathways interact in ossification remains unclear.

Methods: We examined this potential link in patients with fibrodysplasia ossificans progressiva (FOP), a genetic condition of progressive heterotopic ossification caused by activating mutations in the Activin A type I receptor (ACVR1/ALK2).

Clinical-pathological correlations in three patients with fibrodysplasia ossificans progressiva.

Objective: Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic disorder in which heterotopic bone forms in the soft tissues. This often occurs in response to injury or inflammation, leading to joint immobilization and significant disability. There are currently no definitive treatment options for this devastating disease.