Changes in dendritic cell subsets in mice with type 1 diabetes mellitus

Abstract

Objective To investigate the changes in dendritic cell (DC) subsets in mice with type 1 diabetes mellitus (T1DM). Methods A mouse model of diabetes was established through intravenous injection of streptozotocin (STZ) solution. At different time points after STZ treatment, changes in body weight and blood glucose level were observed. Flow cytometry analysis was performed to detect DC subsets, neutrophils, monocytes and CD4+ Foxp3+ regulatory T cells (Treg) in spleen and lymph nodes. Results STZ treatment led to weight loss and increase in blood glucose in mice. Ten days after STZ treatment, no significant difference in the percentages of DC subsets, neutrophils and monocytes in both spleen and lymph nodes was found between T1DM mice and normal controls. However, spleen volume in the mice treated by STZ significantly reduced, and the percentages of DC subsets in spleen decreased whereas the percentages of neutrophils and monocytes increased as compared with those of normal controls on 30 d and 60 d. Moreover, the percentages of DC subsets, neutrophils and monocytes in lymph nodes of STZ-treated mice were significantly lower than those of normal controls. Meanwhile, the percentage of CD4+ Foxp3+ Treg cells in lymph nodes but not in spleen was significantly upregulated as compared with that of normal controls. Conclusion Significant changes in DC subsets and other inflammatory cells in spleen and lymph nodes are observed in mice with STZ-induced diabetes, which reflects the changes in T cell responses and suggests that DC subsets might play an important role in the pathogenesis of T1DM. Key words: Type 1 diabetes mellitus; Dendritic cell; Regulatory T cell (Treg)