Rheumatology: Renal fibroblasts are associated with interstitial fibrosis in lupus nephritis

Purpose: Fibroblasts are extracellular matrix (ECM)-producing cells derived from bone marrow stem cells that contribute to organ fibrosis

The team investigated the presence and characteristics of fibroblasts in peripheral blood and kidneys of lupus nephritis (LN) patients , and the correlation of fibroblast abundance with renal tubular epithelial cells (RTECs) in LN fibrogenesi.

Methods: Using flow cytometry and confocal imaging techniques, fibroblasts were identified with collagen type I (colI), α-smooth muscle actin (α-SMA), CD34 and CD4 The relationship between the level of fibroblasts and pathological features in LN patients was analyz.

The role of RTECs in fibrogenesis was determined in HK-2 cells treated with LN ser.

^{Results: Spindle fibroblasts (colI +} α-SMA ⁺ CD34 ⁺ CD45 ⁺ cells) were present in the peripheral blood of lupus nephritis patients , and the abundance of spindle fibroblasts was higher than that of healthy contro.

^{Renal fibroblasts (colI +} α-SMA ⁺ CD45 ⁺ cells) were found in the tubulointerstitium of patients with LN , and their numbers correlated significantly with the degree of chronic indicators including interstitial fibrosis and renal insufficien.

Stimulation of peripheral blood mononuclear cells with the supernatant of HK-2 cells treated with LN serum resulted in significant fibrogenesis, which was eliminated by the addition of IL-6 neutralizing antibo.

Conclusion: Fibrocytes in blood and kidney tissue of LN patients are significantly increased, especially in patients with interstitial fibrosis

Fibroblasts can be differentiated from blood cells, to which RTECs positively contribute

Source: Kim J, Go H, Lim JS, et .