Effect of Musculin on biological function of mouse bone marrow-derived dendritic cells

Abstract

Objective To investigate the effect of a novel transcription factor, Musculin, on the biological functions of bone marrow-derived dendritic cells (BMDC) in mice. Methods Bone marrow cells from wildtype (WT) and Musculin knockout (KO, -/-) mice were obtained and cultured with granulocyte-macrophage colony stimulating factor (GM-CSF) and IL-4 so as to induce BMDC in vitro. After 7 d, the BMDC were added with lipopolysaccharide (LPS) and continued to culture for 24 h. Besides the cellular morphological changes were observed dynamically, BMDC and the supernatants were collected from the WT and Musculin-/-cells. Flow cytometry was used to analyze the proportion of positive cells of CD11c, CD40, CD80, CD86, PD-L1 and IAIE in each group. CCK-8 assay was adopted to detect the cellular proliferation for stimulating heterologous lymphocytes and the different stimulation indexes (SI) were calculated respectively. ELISA was applied to detect the supernatant contents of IL-1β, IL-6, IL-10, IL-12 (P40), IL-12 (P70) and TNF-α in each group. Results The BMDC from the Musculin-/-group had similar morphology and no significant difference in purity, decreased percentages of co-stimulatory molecules such as CD40, CD80 and CD86 (P < 0.05), and reduced percentages of co-inhibitory molecules PD-L1 and major histocompatibility complex class Ⅱ (MHC-Ⅱ) IAIE though no significant differences when compared with those of WT group. Moreover, the number of heterologous lymphocytes and related SI after of mixed lymphocyte reaction (MLR) were obvious higher in the Musculin-/-group than the WT group, especially after 5 days' stimulation (P < 0.05). In addition, the supernatant levels of proinflammatory factors including IL-1β, IL-6, IL-12 (P40), IL-12 (P70) and TNF-α were significantly increased in the Musculin-/-group than the WT group (P < 0.05), but no such changes were observed in anti-inflammatory factor IL-10 level between the 2 groups. Conclusion Musculin may enhance the immune function mediated by BMDC and suppress inflammatory reaction, suggesting that it can regulate the biological functions on BMDC.

Keywords

• musculin
• bone marrow-derived dendritic cells
• biological functions