Slc11a1 (Nramp-1) gene modulates immune-inflammation genes in macrophages during pristane-induced arthritis in mice

Pristane-induced arthritis (PIA) in AIRmax mice homozygous for Slc11a1 R and S alleles was used to characterize the influence of Slc11a1 gene polymorphism on immune responses during disease manifestation. Previous reports demonstrated that the presence of the Slc11a1 S allele increased the incidence and severity of PIA in AIRmax ^SS , suggesting that this gene could interact with inflammatory loci to modulate PIA. We investigated the effects of Slc11a1 alleles on the activation of phagocytes during PIA.

Mice were injected intraperitoneally with two doses of 0.5 mL of mineral oil pristane at 60-day intervals. Arthritis development was accompanied for 180 days.

AIRmax ^SS mice showed differential peritoneal macrophage gene expression profiles during PIA, with higher expression and production of H₂O₂, NO, IL-1β, IL-6, TNF-α, and several chemokines. The presence of the Slc11a1 R allele, on the other hand, diminished the intensity of macrophage activation, restricting arthritis development.

Our data demonstrated the fine-tuning roles of Slc11a1 alleles modulating macrophage activation, and consequent PIA susceptibility, in those mouse lines.