Western blotting analysis as a tool to study receptor tyrosine kinases

Artesunate interfere in modulation of Foxp3 expression in synovial cells in collagen-induced arthritis rats

OBJECTIVE

To investigate the expression and significance of forkhead/winged helix (Foxp3) in rat synovial cells in collagen-induced arthritis rats after artesunate interventions.

METHODS

A male Wistar rat model of type II collagen-induced arthritis (CIA) was established. The synovia was removed, and synovial cells were cultured for 5-7 generations. The cells were divided into a normal control group, a CIA model group, artesunate groups at different concentrations (5, 10, and 20 ng/mL), and a hydroxychloroquine group. The expressions of the Foxp3 gene in the groups were detected by reverse transcription polymerase chain reaction, and their protein expressions were detected by western blotting.

RESULTS

In the drug intervention and CIA model groups, Foxp3 gene and protein expressions increased. The Foxp3 gene and protein expressions in the drug intervention groups were higher than those in the CIA model group, and fiber-like synovial cells numbers decreased. Foxp3 in the artesunate group was expressed at a greater level than the levels expressed in the control groups (P<0.05). Significantly increased of expression was observed in the 20 ng/mL artesunate group compared with the model group (P<0.05).

CONCLUSIONS

Artesunate could increase the expression of Foxp3 in a dose-dependent manner, and thus reduce pannus formation and erosion of cartilage and bone to prevent lesions from rheumatoid arthritis.

Regulation of receptor tyrosine kinases by miRNA: overexpression of miRNA using lentiviral inducible expression vectors

MicroRNAs have the ability to alter and regulate multiple genes, including RTK family members, making them an attractive approach for molecular therapeutic development. We use a pCDNA6.2-EmGFP-microRNA expression vector to overexpress individual mature microRNA and then transfer the expression cassette into a single, inducible lentiviral vector (pINDUCER20). We successfully use this system to create a pINDUCER-EmGFP-miRNA27a expression vector and generate a stable head and neck cancer cell line (UM-SCC-22A) that inducibly expresses miRNA-27a, resulting in targeted epidermal growth factor receptor down regulation. In this chapter, we describe the protocol for engineering the pINDUCER-EmGFP-microRNA expression vector, producing lentiviral particles for target cell infection, and evaluating downregulation of gene expression.