Tumour necrosis factor-alpha induced CD70 and interleukin-7R mRNA expression in BEAS-2B cells

Over the past few years, evidence has emerged for the potential role of the human bronchial epithelial cell in the initiation and progress of inflammation of the airway. Thus, the aim of this study was to investigate the expression pattern of cytokines and immunomodulatory factors in the human bronchial epithelial cell. To elucidate this highly complex expression and regulation pattern, the simian virus-40 transformed human bronchial-epithelial cell line BEAS-2B was stimulated with human recombinant tumour necrosis factor (hrTNF)-alpha (10 ng x mL(-1) (specific activity, 2.86 x 10(7) U x mg(-1))) and messenger ribonucleic acid (mRNA) expression pattern was analysed by complementary deoxyribonucleic acid (cDNA) array analysis. Among 375 arrayed cDNA clones, 173 (46%) were detected in BEAS-2B cells. The levels of expression of 17 genes, including those of monocyte chemoattractant protein (MCP)-1, intercellular adhesion molecule (ICAM)-1, growth-related oncogene (GRO) alpha, beta, gamma, interleukin (IL)-7 receptor, CD70, IL-6, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF) and regulated in activation, normal T-cell expressed and secreted (RANTES) were elevated after TNF-alpha stimulation. The differential character of 12 clones was further characterised and verified by real time polymerase chain reaction (PCR) analysis of total ribonucleic acid (RNA) isolated from BEAS-2B cells after 4 or 16 h incubation with increasing TNF-alpha concentrations (1 pg-10 ng x mL(-1)). The authors semiquantified concentration-dependent mRNA upregulation of cytokines and immunology factors identified in the array and could determine threshold values of mRNA increases at 10 pg x mL(-1)-1 ng x mL(-1) TNF-alpha by real-time PCR. For CD70 (CD27 ligand) and interleukin-7 receptor, which to the best of the author's knowledge have not yet been described in the human bronchial epithelial cell, a rapid and continuous messenger ribonucleic acid increase induced by 100 pg x mL(-1) tumour necrosis factor-alpha after only 60-90 min was shown. A potential role for these genes in the inflammatory process in the human bronchial epithelial cell is proposed.