PROBLEM: The objective of this study was to examine the susceptibility of rat uterine epithelial cells (UEC) to infection with Chlamydia trachomatis and to study the epithelial-stromal interactions following infection. METHOD OF STUDY: UEC were isolated from adult rats and grown in culture. Polarized, confluent monolayers of UEC were infected with 10(6) IFU/well C. trachomatis (MoPn). In order to confirm infection, MoPn was labeled with a fluorescent tracking dye, PKH-26, and then used in epithelial cell infections. Transepithelial resistances were measured prior to and following infection to test the effect of Chlamydia on the integrity of the epithelial monolayers. In other experiments, polarized epithelial cultures were infected in the presence and absence of stromal cells. Media was collected from the apical and basolateral compartments of the cultures before and after infection and analyzed for cytokines IL-1alpha and TNF-alpha. RESULTS: Epithelial cell cultures infected with PKH-26 labeled MoPn were examined 4-5 days later. Bacterial inclusions were detected inside epithelial cells indicating infection had occurred. Co-localization of PKH-26 labeled bacteria with FITC-labelled anti-Chlamydia antibody on the epithelial cells confirmed infection. No changes were found in resistance across the monolayers of epithelial cells in the presence or absence of infection. ELISA results indicate that UEC secrete IL-1alpha constitutively in citro. Stromal cells secrete very little IL-1alpha. When stromal cells were co-incubated with epithelial cells there was a decrease in the amount of IL-1alpha secreted by epithelial cells 48 hr post-infection. On the other hand, maximum TNF-alpha was found in stromal cells. both with and without infection. Epithelial cells, in these studies made very little TNF-alpha. CONCLUSIONS: These results show that primary rat epithelial cells can be infected with Chlamydia in vitro. Epithelial and stromal cells from uteri of adult rats make IL-1alpha and TNF-alpha in vitro both prior to and following infection with Chlamydia. This system can be used to analyze the role played by epithelial-stromal interactions in providing protection on this mucosal surface.

Animals↗

PubMed2000

Elective versus symptomatic antibiotic treatment in cystic fibrosis patients with chronic Pseudomonas infection of the lungs.

BACKGROUND: A previous retrospective study suggested that a policy of regular anti-pseudomonal antibiotic treatment improved pulmonary function and increased survival in patients with cystic fibrosis chronically infected with Pseudomonas species. The results of a prospective multicentre study to compare the effects on pulmonary function and mortality of three monthly elective anti-pseudomonal antibiotic treatment with conventional symptomatic treatment are reported. METHODS: Sixty patients with cystic fibrosis, chronically infected with P aeruginosa, were randomised to the two treatment arms (elective or symptomatic) and followed clinically at yearly reviews. The major end points were changes in forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). Survival was a secondary end point. RESULTS: Patients in the symptomatic group received a mean of three antibiotic treatments each year and those in the elective group received four antibiotic treatments during each year of the study. No significant differences in FEV(1) and FVC were found between the two groups after three years. There was a statistically non-significant higher rate of deaths in the elective group (n = 4), three of which were associated with B cepacia infection, compared with the symptomatic group (n = 0). CONCLUSIONS: This study did not demonstrate an advantage of a policy of elective antibiotic treatment over symptomatic treatment in patients with cystic fibrosis chronically infected with Pseudomonas species.

Adolescent↗

PubMed1999