Cell samples ranging from 1.16 × 10(5) to 3.06 × 10(5) cells/per sample were obtained. Of 11 samples, 7 formed confluent cultures, while the remaining 4 samples showed only patches of epithelial cells. Neither fungal nor bacterial contamination posed a problem. Immunocytochemistry of the cytospin slides confirmed the presence of epithelial cells in the cultures. No adverse effects were experienced by the volunteers.

No abstract

We compared airway epithelial cell models relevant for cystic fibrosis (CF): 16HBE cells with endogenous wild-type cystic fibrosis transmembrane conductance regulator (CFTR), CFBE cells with mutated DF508-CFTR, corrected CFBE cells overexpressing CFTR, CFSME (CF submucosal) and Calu-3 (non-CF submucosal) cells with respect to the epithelial sodium channel (ENaC), inducible NO synthase (iNOS) and mucins (MUC) (studied by quantitative Real-Time-Polymerase Chain Reaction, qRT-PCR and Western blot), and wound healing. CFBE cells had significantly more expression of band g-ENaC mRNA and of b-ENaC protein than 16HBE cells. Compared to corrected CFBE cells, CFBE cells had increased mRNA expression of all ENaC subunits and b-ENaC protein. For ENaC, the CFSME/Calu-3 mRNA ratio was very low and contradictory to the ENaC upregulation in CF cells. CFBE cells showed decreased expression of iNOS at both mRNA and protein levels compared to 16HBE cells and only at the mRNA level compared to corrected CFBE cells. CFSME cells showed expression of iNOS whereas Calu-3 cells did not. Higher expression of MUC2 and MUC5B was found in corrected CFBE cells compared to CFBE cells. Wound healing in CFBE cells was delayed compared to corrected CFBE cells, but not to 16HBE cells, and in CFSME cells compared to Calu-3 cells. Our data suggest CFSME as an inappropriate CF cell model for Calu-3 cells, and provide partial support for the theory that the differences (in ENaC, iNOS and wound healing) between these cell lines are associated to the presence of CFTR in the bronchial airway epithelial cells.

Bacteria affect the respiratory epithelium, which is covered by airway surface liquid (ASL) and mucus. Ion concentrations in the ASL are determined by the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na(+) channel (ENaC). Neonatal sepsis is a major risk factor for subsequent pulmonary disease in preterm newborns. Predominating are coagulase-negative staphylococci (e.g., Staphylococccus epidermidis and Staphylococccus aureus). The aim of this study was to investigate modulation of CFTR, ENaC, mucins, proinflammatory cytokines, and inducible nitric oxide synthase (iNOS) in respiratory epithelial cells after S. epidermidis 94B080 and S. aureus 90B083 exposure. Bronchial epithelial cells were incubated with S. epidermidis 94B080 and S. aureus 90B083 (neonatal blood isolates) for 1-36 h. Expression of CFTR, ENaC, iNOS, and mucins was analyzed by real-time PCR and Western blotting. Release of cytokines was analyzed by ELISA, and production of NO by the Griess assay. Expression of CFTR significantly decreased after 36 h incubation with S. epidermidis and more prominently with S. aureus, whereas S. epidermidis caused a significant increase in the expression of β- and γ-ENaC. Expression of iNOS increased, but NO was not detected. Both staphylococci caused a decrease in the intracellular Ca(2+) concentration. S. aureus induced increased secretion of IL-6, IL-8, and transforming nuclear factor (TNF)-α in a time-dependent manner as compared with S. epidermidis. In conclusion, expression of ENaC, CFTR, and iNOS is modulated by exposure to S. aureus 90B083 and S. epidermidis 94B080. S. aureus is more potent in causing release of IL-6, IL-8, and TNF-α by bronchial epithelial cells as compared with S. epidermidis. The mRNA expression for the mucus proteins MUC2, MUC5AC, and MUC5B could not be measured, neither in the presence nor in the absence of bacteria.

Ambroxol, a mucokinetic anti-inflammatory drug, has been used for treatment of cystic fibrosis (CF). The respiratory epithelium is covered by the airway surface liquid (ASL), the thickness and composition of which is determined by Cl(-) efflux via the cystic fibrosis transmembrane conductance regulator (CFTR) and Na(+) influx via the epithelial Na(+) channel (ENaC). In cells expressing wt-CFTR, ambroxol increased the Cl(-) conductance, but not the bicarbonate conductance of the CFTR channels. We investigated whether treatment with ambroxol enhances chloride transport and/or CFTR and ENaC expression in CF airway epithelial cells (CFBE) cells. CFBE cells were treated with 100 µM ambroxol for 2, 4 or 8 h. mRNA expression for CFTR and ENaC subunits was analysed by real-time polymerase chain reaction (RT-PCR); protein expression was measured by Western blot. The effect of ambroxol on Cl(-) transport was measured by Cl(-) efflux measurements with a fluorescent chloride probe. Ambroxol significantly stimulated Cl(-) efflux from CFBE cells (a sixfold increase after 8 h treatment), and enhanced the expression of the mRNA of CFTR and α-ENaC, and of the CFTR protein. No significant difference was observed in β-ENaC after exposure to ambroxol, whereas mRNA expression of γ-ENaC was reduced. No significant effects of ambroxol on the ENaC subunits were observed by Western blot. Ambroxol did not significantly affect the intracellular Ca(2+) concentration. Upregulation of CFTR and enhanced Cl(-) efflux after ambroxol treatment should promote transepithelial ion and water transport, which may improve hydration of the mucus, and therefore be beneficial to CF-patients.

These findings suggest that if internalization of P. aeruginosa reduces infection, GC therapy would increase the risk of pulmonary infection by decreasing the internalization of P. aeruginosa in CF cells, but GCs may improve airway hydration by increasing the intracellular Ca(2+) concentration. Whether the benefits of GC treatment outweigh the negative effects is questionable, and further clinical studies need to be carried out.

Canavan disease (OMIM 271900) is an autosomal recessive lethal neurodegenerative disorder characterized by spongy degeneration of the brain. A highly consanguineous Pakistani family with Canavan disease was enrolled on the basis of diagnosis. All the affected individuals have mental retardation, megalocephaly and degradation of motor skills, poor head control, partial vision loss, weakness of the muscles and raised urinary concentration of N-acetyl aspartic acid in the urine. Blood samples were collected from affected as well as normal siblings and processed for DNA purification. Linkage analysis was performed by typing three short tandem repeat markers D17S1583 (7.19 cM), D17S1828 (10.02 cM) and D17S919 (14.69 cM) for an already-reported gene/locus ASPA at chromosome 17p13.2 causing Canavan disease. During linkage analysis, all the affected individuals were homozygous for short tandem repeat markers while the normal siblings were heterozygous showing co-segregation of the disease. Gene ASPA (NM_000049) was undertaken to sequence for mutation analysis. As a result of sequence analysis, we found missense substitution 740A→G (p.G274R) in exon 6 of gene ASPA. To our knowledge, this is the first report about Canavan disease on a Pakistani family.

No abstract