To observe the accumulation of dendritic cells (DCs) in rat remnant kidney and its contribution to tubulointerstitial fibrosis, under influence of valsartan on DCs, a rat remnant kidney model was established by subtotal nephrectomy. Four experimental groups were included: normal, sham, model (SNx) and the group treated with Valsartan (SNxV). Rats were killed at week 1, 4 and 12, respectively. CD1a^+CD80^+ DCs were assayed by double immunostaining method and the images were analyzed with Axioplan 2 microscopy. The expressions of P-selectin, TGF-β1, α-SMA, collagen Ⅲ and fibronectin were analyzed by immunohistochemistry or semi- quantitative RT-PCR, and the level of tubulointerstitial firosis (TIF) was scored. CD1a^+CD80^+ DCs were gradually increased among renal tubules, interstitium and vessels, especially in interstitium, and the number of DCs in model group at week 12 was much more than that in model groups at week 1 or 4. The expressions of P-selectin, TGF-β1, α-SMA, collagen Ⅲ and fibronectin in tubulointerstitial areas and the degree of TIF were increased substantially in model group at week 12. The accumulation of DCs in interstitium was well associated with the loss of renal function and the progression of tubulointerstitial fbrosis. Valsartan treatment inhibited the local accumulation of DCs and attenuated renal tubulointerstitial damage. The local DCs accumulation was related to tubulointerstitial fibrosis and renal dysfunction following renal ablation. Blockade to angiotensin II might be a potent way to attenuate renal immuno-inflammatory injury. Cellular & Molecular Immunology. 2006;3(3):213-220.
Dendritic cells (DCs) are known to be the most powerful professional antigen-presenting cells so far. It could activate primary immune response, and also downregulate immune response. DCs have a unique character of immunoregulation. DC-SIGN, a molecule designated as CD209, is one member of the C-type lectin superfamily. It is not only a pattern recognition receptor but implicated in immunoregulation of DCs. DC-SIGN has become hotspot of recent studies because of its important role in mediating DC adhesion, migration, inflammation, activating primary T cell, triggering immune response and participating in immune escape of pathogens and tumors. These studies on DC-SIGN involved in primary and secondary immune response and relevant mechanism will certainly provide us with a new method in treating and preventing certain diseases.