[Association between autophagy and systemic juvenile idiopathic arthritis and related mechanism: a preliminary study]

To study the role of autophagy in the development of systemic juvenile idiopathic arthritis (sJIA) by analyzing the expression of microtubule-associated protein 1 light chain 3-II (LC3-II), myeloid differentiation factor 88 (MyD88), and suppressor of T-cell receptor signaling 1 (STS-1) in peripheral blood lymphocytes of children with sJIA.

A total of 26 children with sJIA were enrolled as the sJIA group, and 26 healthy children were enrolled as the control group. Western blot was used to measure the protein expression of LC3-II, STS-1, and MyD88 in peripheral blood lymphocytes. Immunofluorescence assay was used to measure the expression of LC3-II in the cytoplasm of lymphocytes. Pearson correlation analysis was used to assess the correlation between indices.

Compared with the control group, the sJIA group had significant increases in the expression of LC3-II, STS-1, and MyD88 (P<0.05). In the sJIA group, the expression of LC3-II was positively correlated with that of MyD88 (r=0.478, P<0.05), and the expression of STS-1 was also positively correlated with that of MyD88 (r=0.817, P<0.05).

There is high expression of LC3-II in peripheral blood lymphocytes of children with sJIA, suggesting that the development of sJIA may be associated with excessive expression of autophagy. STS-1 may induce autophagy by activating some signaling pathways, and MyD88 may participate in autophagy through the Toll-like receptor signaling pathway.