We demonstrated, for the first time, that in the CIA mouse model, IA9 and IA31-LPC systemically administered after induction of arthritis both markedly suppress the rate of disease progression and joint inflammation, diminish release of plasma and joint proinflammatory cytokines and CSF-1, and significantly decrease synovial tissue sublining CD68, F4/80, TREM-1 and TREM-2 expression. This evidence concerns the gene TREM1 and arthritic joint disease.