Disease in BPSM1 mice is independent of the adaptive immune system, Myd88, or GM-CSF. Sections through the ankle of 100-d-old WT (A), BPSM1+/m (B), BPSM1+/+/Mb1-creKi/Ki (C), BPSM1+/+/CD3−/− (D), BPSM1+/+/Myd88−/− (E), and BPSM1+/+/GM-CSF−/− (F) mice showing similar bone erosion in all of the mice carrying the BPSM1 mutation.