The role of DC-SIGN in tubulointerstitial lesions (TILs) and the effect of anti-P-selectin lectin-EGF domain monoclonal antibody (PsL-EGFmAb) were investigated in rat nephrotoxic nephritis (NTN). On Day 4, immature DC-SIGN+DCs infiltrated into renal tubulointerstitium and matured by Day 14, showing increased migratory capacity and ability to induce T cell proliferation. The distribution of DC-SIGN+ DC significantly correlated with crescent formation, TIL severity, and changes in renal function. RANTES and TNF-alpha mRNA were continuously up-regulated from Day 4, while IL-10 mRNA was down-regulated after a marked increase on Day 4. Expression of IFN-gamma and IL-4 mRNA increased on Day 14 due to DC maturation. PsL-EGFmAb suppressed DC maturation, migration and ability to activate T cells. It also down-regulated TNF-alpha and up-regulated IL-10, resulting in a Th1/Th2 bias. The number of crescents decreased and TILs and renal function improved. These results suggest that DC-SIGN mediates DC tubulointerstitial infiltration and is an important regulator of local immune reactions and TILs. PsL-EGFmAb inhibited DC migration, maturation and function by targeting DC-SIGN, and may therefore be a potential treatment for NTN.