Association of BAFF with PI3K/Akt/mTOR signaling in lupus nephritis

Systemic lupus erythematosus is a connective tissue disease characterized by autoimmune inflammation, which leads to specific and nonspecific immune disorders with the formation of various autoantibodies by activated B cells. B‑cell‑activating factor (BAFF) is secreted by macrophages and activated T cells, and is responsible for the proliferation, maturation and differentiation of B cells. However, the mechanism of BAFF involvement in lupus nephritis (LN) remains unclear. The aim of the present study was to investigate the association between BAFF and phosphoinositide 3‑kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling in order to elucidate the pathogenesis of LN. In the present study, 18 patients with LN and 20 controls were included. The clinical data were analyzed and plasma levels of BAFF were measured using an ELISA. The mRNA and protein levels of BAFF, phosphorylated (p)‑PI3K, p‑Akt and p‑mTOR in kidney tissues were measured using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting. Plasma BAFF levels were significantly increased in patients with LN compared with the controls (P<0.001). mRNA and protein levels of BAFF, p‑PI3K, p‑Akt and p‑mTOR in kidney tissue were significantly increased in patients with LN compared with the controls (all P<0.001). mRNA and protein levels of BAFF in the kidney tissues of patients with LN were positively correlated with the levels of p‑PI3K, p‑Akt and p‑mTOR. The results of the present study revealed a correlation between BAFF and the PI3K/Akt/mTOR signaling pathway, and it is hypothesized that they are involved in the pathogenesis of LN.