RNA and protein level of insulin in IPCs. (A) After glucose stimuli IPCs with or without laminin 411 group mRNA level of insulin was determined using RT-PCR and expressed relative to an undifferentiated control and normalized to GAPDH. (B) Insulin release assay. At the end of the 4 stage culture of IPCs, high concentration of glucose was added. Supernatant was collected and tested by ELISA. (C) Immunofluorescence staining of insulin of IPCs with or without laminin 411. After culturing them for 4 stages, IPCs with or without laminin 411 were incubated with anti-human insulin antibody. Nuclei were stained blue with DAPI. Each bar is the mean ± SEM (n = 3), *P < 0.05.