Objective: To disclose whether BCG can enhance Fall-39 gene expression in human pulmonary gland epithelial cells, and to isolate and identify the bioactive proteins that stimulate Fall-39 gene expression in human pulmonary gland epithelial cells.
Methods: Fall-39 mRNA expression in SPC-A-1 cells was detected by using RT-PCR. The cell wall proteins were isolated by sucrose density-gradient centrifugation and fractionated by Sephadex G-75 column chromatography. The antibacterial activity of the cell culture supernatant was determined by agarose radial diffusion assay.
Results: The enhanced expression of Fall-39 mRNA was dose- and time-dependent. BCG cell wall proteins fraction 4 had an activity that remarkably enhanced Fall-39 mRNA expression in SPC-A-1 cells and augmented antibacterial activity of the cell culture supernatant.
Conclusion: These results indicated that BCG could stimulate Fall-39 mRNA expression in human pulmonary gland epithelial cells, thus providing an evidence base for shaping well a new strategy to enhance mucosa antibiotic peptide expression for the prevention and treatment of mucosal infections.