Osteopetrosis in mice lacking NF-kappaB1 and NF-kappaB2

Nat Med. 1997 Nov;3(11):1285-9. doi: 10.1038/nm1197-1285.


The nfkb1 and nfkb2 genes encode closely related products regulating immune and inflammatory responses. Their role during development and differentiation remains unclear. The generation of nfkb1 null mice (p50-/-) resulted in altered immune responses, but had no effect on development. Similarly, nfkb2 knockout mice (p52-/-) did not show developmental defects (J.C. et al., manuscript submitted). We have investigated the potential for in vivo compensatory functions of these genes by generating double-knockout mice. The surprising result was that the animals developed osteopetrosis because of a defect in osteoclast differentiation, suggesting redundant functions of NF-kappaB1 and NF-kappaB2 proteins in the development of this cell lineage. The osteopetrotic phenotype was rescued by bone marrow transplantation, indicating that the hematopoietic component was impaired. These results define a new mouse osteopetrotic mutant and implicate NF-kappaB proteins in bone development, raising new directions in the treatment of bone disorders.

MeSH terms

  • Animals
  • Bone Remodeling / genetics
  • Cell Differentiation
  • Flow Cytometry
  • Hematopoietic Stem Cells / cytology
  • Mice
  • Mice, Knockout
  • Models, Biological
  • NF-kappa B / deficiency*
  • NF-kappa B / genetics
  • NF-kappa B / physiology
  • NF-kappa B p50 Subunit
  • NF-kappa B p52 Subunit
  • Osteoclasts / cytology
  • Osteopetrosis / genetics
  • Osteopetrosis / physiopathology*
  • Phenotype


  • NF-kappa B
  • NF-kappa B p50 Subunit
  • NF-kappa B p52 Subunit