Glucocorticoid receptors in bronchial epithelial cells in asthma

The present study examined two contrasting multilevel model structures to describe the developmental (longitudinal) changes in strength and aerobic power in children: 1) an additive polynomial structure and 2) a multiplicative structure with allometric body size components. On the basis of the maximum log-likelihood criterion, the multiplicative "allometric" model was shown to be superior to the additive polynomial model when fitted to the data from two published longitudinal studies and to provide more plausible solutions within and beyond the range of observations. The multilevel regression analysis of study 1 confirmed that aerobic power develops approximately in proportion to body mass, m1/3. The analyses from study 2 identified a significant increase in quadriceps and biceps strength, in proportion to body size, plus an additional contribution from age, centered at about peak height velocity (PHV). The positive "age" term for boys suggested that at PHV the boys were becoming stronger in the quadriceps and biceps in relation to their body size. In contrast, the girls' age term was either negligible (quadriceps) or negative (biceps), indicating that at PHV the girls' strength was developing in proportion to or, in the case of the biceps, was becoming weaker in relation to their body size.     

Erythromycin modulates IL-8 expression in normal and inflamed human bronchial epithelial cells

Previous studies have shown that blood plasma levels of 17alpha, 20beta-dihydroxy-4-pregnen-3-one (DHP) and 17alpha, 20beta, 21-trihydroxy-4-pregnen-3-one (20beta-S) increase in striped bass (Morone saxatilis) undergoing final oocyte maturation (FOM). Both hormones are produced by ovarian fragments undergoing hCG-induced germinal vesicle breakdown (GVBD) in vitro. In the present study, we investigated binding of DHP and 20beta-S to ovarian membranes from striped bass undergoing FOM. Saturable binding sites for DHP were not detected. Saturation of 20beta-S binding sites with 5 nM [3H]20beta-S occurred within 40 min at 0 degrees C (at 3 min, half of the maximum specific binding of steroid was calculated to have occurred), and the binding was pH-dependent. Scatchard analyses revealed the presence of a single class of high-affinity (dissociation constant [Kd] = 1.4 +/- 0.2 nM), limited-capacity (estimated concentration [Bmax] = 2.7 +/- 0.3 pmol/g ovary) 20beta-S binding sites on membranes from striped bass ovaries undergoing FOM. In contrast, only low levels of specific binding (Bmax < 0.04 pmol/g tissue) were detected on membranes from testes, liver, brain, and muscle. Ovarian membranes prepared from vitellogenic females also had low levels (Bmax < 0.1 pmol/g ovary) of specific 20beta-S binding, less than 5% of that found during FOM. Results of competition assays showed that DHP was approximately 250 times less effective than 20beta-S for displacing 20beta-S from ovarian membranes. In contrast, 20beta, 21-dihydroxy-4-pregnen-3-one was a very effective competitor, although it is only a weak inducer of oocyte GVBD in vitro. Of several other steroids tested, only progesterone showed affinity for the 20beta-S binding site within a physiological range of concentrations. Taken together with previous studies of striped bass FOM, these findings indicate that 20beta-S is the oocyte maturation-inducing steroid hormone in striped bass.     

Expression of prostaglandin receptors EP4 and FP in human lens epithelial cells

Physicians have at their disposal a great number of established diagnostic tests, and new ones continue to be developed that are potentially helpful in diagnosing and establishing the prognosis of disease. Many of these tests were either inadequately evaluated or were found, on more careful scrutiny, to be less helpful than first believed. To ensure optimal patient care as well as appropriate use of health care resources, practitioners must be adept in understanding the true efficacy of diagnostic tests that they ask patients to undergo. They must be able to understand the basic language applied in evaluating tests and be able to determine if and when tests are applicable. (J Am Assoc Gynecol Laparosc 6(1):105-112, 1999)     

Roxithromycin inhibits cytokine production by and neutrophil attachment to human bronchial epithelial cells in vitro

We evaluated the effect of roxithromycin on cytokine production and neutrophil attachment to human airway epithelial cells. Roxithromycin suppressed production of interleukin 8 (IL-8), IL-6, and granulocyte-macrophage colony-stimulating factor. It inhibited neutrophil adhesion to epithelial cells. Roxithromycin modulates local recruitment and activation of inflammatory cells, which may have relevance to its efficacy in airway diseases.     

An improved method to obtain highly differentiated monolayers of human bronchial epithelial cells

BACKGROUND: Image-guided percutaneous drainage has been shown to be a safe and effective alternative to surgery in the management of psoas abscess in adults and adolescents. There is little information on its use in children. OBJECTIVE: To evaluate the safety and efficacy of US-guided percutaneous needle aspiration and catheter drainage of ilio-psoas abscesses. MATERIALS AND METHODS: A retrospective review of 14 children with 16 ilio-psoas abscesses (10 pyogenic and 4 tuberculous) who were treated by US-guided percutaneous needle aspiration (n = 5) or catheter drainage (n = 9) along with appropriate antimicrobial therapy. RESULTS: Percutaneous treatment was successful in 10 of the 14 patients; all showed clinical improvement within 24-48 h of drainage and subsequent imaging demonstrated resolution of the abscess cavities. Surgery was avoided in all of these ten patients except one, who underwent open surgical drainage of ipsilateral hip joint pus. Of the other four patients, two had to undergo surgical drainage of the ilio-psoas abscesses after failure of percutaneous treatment, one improved with antibiotics after needle aspiration failed to yield any pus, and one died of continuing staphylococcal septicaemia within 24 h of the procedure. There were no procedural complications. CONCLUSIONS: Percutaneous drainage represents an effective alternative to surgical drainage as a supplement to medical therapy in the management of children with ilio-psoas abscesses.     

Hyperosmolarity-induced interleukin-8 expression in human bronchial epithelial cells through p38 mitogen-activated protein kinase

The changes in airway osmolarity have been described to contribute to the production of exercise- induced bronchoconstriction (EIB) and the development of the late-phase response (LPR). The mechanism has been investigated; however, the responsiveness of bronchial epithelial cells (BEC) to hyperosmolarity and the intracellular signals leading to cell activation have not been determined. In this study, we examined the effect of hyperosmolar medium on interleukin-8 (IL-8) expression and the role of p38 mitogen-activated protein (MAP) kinase and c-Jun NH2 terminal kinase ( JNK) in human BEC in this response in order to clarify the intracellular signals regulating IL-8 expression in hyperosmolarity-stimulated BEC. The results showed that hyperosmolarity induced IL-8 expression in a concentration dependent manner, p38 MAP kinase phosphorylation and activation, and JNK activation whether NaCl or mannitol was used as the solute. SB 203580 as the specific p38 MAP kinase inhibitor inhibited hyperosmolarity-induced p38 MAP kinase activation and partially inhibited hyperosmolarity-induced IL-8 expression. These results indicate that p38 MAP kinase, at least in part, regulates hyperosmolarity-induced IL-8 expression in BEC. However, other signals such as JNK are possibly also involved. These results provide new evidence on the mechanism responsible for the development of the LPR induced by EIB, and a strategy for treatment with the specific p38 MAP kinase inhibitor.     

Interleukin 1alpha and interleukin 6 promote the in vitro growth of both normal and neoplastic human cervical epithelial cells

We report here on a patient who was diagnosed with follicular carcinoma in 1985, and who was treated with total thyroidectomy. Two years later, when metastasis was found in his neck lesion, lung, pelvis and right femur, the patient received 131I treatment. Six years after receiving 131I treatment, the patient presented with hyperthyroidism. Whole-body scan with 131I revealed functioning metastasis in his right femur and pelvis. There was no hot spot in the neck region, confirming that no thyroid tissue remained. Blood panels revealed an increase in both TSH binding inhibitory immunoglobulin (TBII. 36.2%; normal. -10 approximately 10%) and thyroid stimulating antibody (TSAb, 176%; normal, less than 145%). Treatment with antithyroid drugs, dexamethasone and radioisotope therapy rapidly resolved his hyperthyroidism. Thyrotoxicosis and positive TRAb occurred in the absence of thyroid tissue, and many years after the completion of R1 therapy. The overproduction of thyroid hormone can therefore only be attributed to some mechanism of activity in the metastatic tumor tissue.     

Neutrophil and asbestos fiber-induced cytotoxicity in cultured human mesothelial and bronchial epithelial cells

This study investigates reactive oxygen species generation and oxidant-related cytotoxicity induced by amosite asbestos fibers and polymorphonuclear leucocytes (PMNs) in human mesothelial cells and human bronchial epithelial cells in vitro. Transformed human pleural mesothelial cells (MET 5A) and bronchial epithelial cells (BEAS 2B) were treated with amosite (2 micrograms/cm2) for 48 h. After 24 h of incubation, the cells were exposed for 1 h to nonactivated or amosite (50 micrograms) activated PMNs, washed, and incubated for another 23 h. Reactive oxygen species generation by the PMNs and the target cells was measured by chemiluminescence. Cell injury was assessed by cellular adenine nucleotide depletion, extracellular release of nucleotides, and lactate dehydrogenase (LDH). Amosite-activated (but also to a lesser degree nonactivated) PMNs released substantial amounts of reactive oxygen metabolites, whereas the chemiluminescence of amosite-exposed mesothelial cells and epithelial cells did not differ from the background. Amosite treatment (48 h) of the target cells did not change intracellular adenine nucleotides (ATP, ADP, AMP) or nucleotide catabolite products (xanthine, hypoxanthine, and uric acid). When the target cells were exposed to nonactivated PMNs, significant adenine nucleotide depletion and nucleotide catabolite accumulation was observed in mesothelial cells only. In separate experiments, when the target cells were exposed to amosite-activated PMNs, the target cell injury was further potentiated compared with the amosite treatment alone or exposure to nonactivated PMNs. In conclusion, this study suggests the importance of inflammatory cell-derived free radicals in the development of amosite-induced mesothelial cell injury.     

Interleukin 4 inhibits growth and induces apoptosis in human breast cancer cells

Interleukin-4 (IL-4) is a pleiotropic cytokine produced by mast cells and T lymphocytes that promotes proliferation and immunoglobulin class-switching in B cells. IL-4 receptors (IL-4Rs) are also expressed by nonhematopoietic cells as well as some tumor cells. Unlike its mitogenic effect on B cells, IL-4 inhibits the growth of some cancer cells in vitro. In this study, we show that IL-4R is expressed by breast and ovarian cancer cell lines. Furthermore, anchorage-dependent and -independent growth of breast cancer cell lines MCF-7 and MDA-MB-231 is inhibited by IL-4 treatment, and this effect requires IL-4R. Interestingly, IL-4 only inhibited proliferating breast cancer cells and had no effect on basal, unstimulated growth. We therefore characterized the effect of IL-4 on breast cancer cell growth stimulated by either estradiol or insulin-like growth factor I (IGF-I). In both anchorage-dependent and -independent growth assays, IL-4 inhibited estradiol-stimulated growth. The antiestrogen effect of IL-4 was not due to IL-4 interference with the estrogen receptor, because IL-4 did not interfere with estrogen receptor-mediated reporter gene transactivation. In contrast, IL-4 had no effect on IGF-I-stimulated proliferation. Because IGF-I is known to inhibit programmed cell death, we examined apoptosis as a possible mechanism of IL-4 action. We established that IL-4 induced apoptosis in breast cancer cells by five independent criteria: (a) morphological indicators including pyknotic nuclei and cytoplasmic condensation; (b) DNA fragmentation; (c) the formation of DNA laddering; (d) the cleavage of poly(ADP-ribose) polymerase; and (e) the presence of cells with sub-G1 DNA content. IL-4 increased the percentage of apoptotic cells in MCF-7 and MDA-MB-231 cells 6.0- and 6.7-fold over that of the control, respectively. Finally, the addition of IGF-I reversed IL-4-induced apoptosis, suggesting that the mechanism of IL-4-induced growth inhibition in human breast cancer cells is the induction of programmed cell death.     

Interaction between glucocorticoids and beta2-agonists: alpha and beta glucocorticoid-receptor mRNA expression in human bronchial epithelial cells

Disabled-2 (Dab2), a mammalian structural homolog of Drosophila Disabled (Dab), is a mitogen-responsive phosphoprotein. It has been speculated to be a negative regulator of growth since its expression is lost in ovarian carcinomas. Dab2 contains a C-terminal proline-rich domain with sequences similar to those found in Sos, a guanine nucleotide exchange factor for Ras. The proline-rich sequences of Sos mediate the interaction of Sos with Grb2, an adaptor protein which coupled tyrosine kinase receptors to Sos. Herein, we have investigated the possibility that Dab2 interacts with Grb2. In experiments of co-immunoprecipitation from BAC1.2F5 macrophage cell lysates, significant quantities of Grb2 were associated with both Sos and Dab2, although Dab2 and Sos were not present in the same complex. Transfection of Dab2 into a Dab2-negative cell line (293 cells) decreased the amount of Grb2 associated with Sos, suggesting that Dab2 competes with Sos for binding to Grb2. Proline-rich peptides corresponding to Dab2 (#661-669) and to Sos (#1146-1161) inhibited the binding of Dab2 to Grb2, but were less effective in disrupting the Grb2-Sos complex. The expressed proline-rich domain of Dab2 (#600-730) bound Grb2, but other regions of Dab2 failed to bind Grb2. Both of the individual SH3 domains of Grb2 bound to Sos (N-terminal SH3 domain > C-terminal SH3 domain), but binding to Dab2 required the intact Grb2, suggesting cooperative binding using both SH3 domains of Grb2. These data indicate that Dab2 binds to the SH3 domains of Grb2 via its C-terminal proline-rich sequences. Dab2 may modulate growth factor/Ras pathways by competing with Sos for binding to Grb2.     

Cytokeratin expression in human oral gingival epithelial cells: in vitro regulation by titanium-based implant materials

To evaluate whether cytokeratin expression in human oral epithelial cells could be influenced by implant materials used in dental surgery, passaged human oral gingival epithelial cells were seeded on commercially pure titanium (CP-Ti) or on Ti6Al4V titanium alloy. Confluence was achieved after about 15 days on both substrates. Cells formed at that time, an organized layer of densely packed polygonal cells, and harbored a filamentous cytokeratin network typical of epithelial cells. Immunochemistry and immunoblot analysis were used to detect modifications of the amount of individual CK polypeptides (CK7, 8, 13, 18 and 19) in function of the culture substrate. Results showed that the level of CK8, CK18 and CK19 expression was not altered whatever the culture substrate used. The expression of CK13 was reduced in epithelial cells cultured on the titanium alloy, as compared with commercially pure titanium. Conversely, the level of CK7 was higher on the Ti6Al4V alloy than on commercially pure titanium. This study suggests that titanium-based implant materials could influence differently the phenotype of oral gingival epithelial cells.     

Vitamin D receptors and anti-proliferative effects of vitamin D derivatives in human pancreatic carcinoma cells in vivo and in vitro

The GER human pancreatic carcinoma cell line possesses receptors for 1,25-dihydroxyvitamin D3. We report that the vitamin D analogue EB 1089 inhibits the growth of these cells in vitro and when grown as tumour xenografts in immunodeficient mice. Tumour-bearing mice were given EB 1089 at a dose of 5 microg kg(-1) body weight i.p. thrice weekly for 4-6 weeks. Tumour growth was significantly inhibited in treated animals compared with controls in the absence of hypercalcaemia. These findings may have therapeutic implications in pancreatic cancer.     

Increased interleukin-8 release by beta-adrenoceptor activation in human transformed bronchial epithelial cells

1. The effect of beta-adrenoceptor activation on release of the neutrophil chemoattractant, interleukin-8 (IL-8), was examined in human transformed bronchial epithelial cells (16HBE cells). 2. The combined beta 1- and beta 2-adrenoceptor agonist, isoprenaline, time- (100 nM, 2-18 h) and concentration- (1-30 nM) dependently increased IL-8 protein content in the cell culture supernatant as measured by an enzyme immunosorbent assay standardized for DNA by fluoro-colorimetry. 3. Isoprenaline (1-100 nM, 15 min) increased cyclic AMP concentration-dependently. 4. The effect of isoprenaline (100 nM) was inhibited by the beta-adrenoceptor blocker propranolol (10 microM). The maximum magnitude of IL-8 increase caused by beta-adrenoceptor activation was 40% of that caused by the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha 100 ng ml-1). 5. The selective beta 2-adrenoceptor agonist salbutamol (1 microM), increased IL-8 protein similarly to isoprenaline and the cyclic AMP analogue, dibutyryl cyclic AMP (1 mM) produced a corresponding effect. 6. Pretreatment with isoprenaline (100 nM) followed by TNF-alpha (20 ng ml-1) increased IL-8 additively. 7. In conclusion, beta-adrenoceptor stimulation increased the release of the neutrophil chemoattractant, IL-8 in 16HBE cells, via an increase in intracellular cyclic AMP. beta-adrenoceptor stimulation adds to the IL-8 increase caused by the pro-inflammatory cytokine TNF-alpha. If this mechanism exists in vivo, beta-adrenoceptor activation may increase neutrophil chemotaxis into the airways.     

Comparison of the toxic effects of hydrogen peroxide and ozone on cultured human bronchial epithelial cells

In this study, we compared the cytotoxic and genotoxic effects of hydrogen peroxide and ozone on cultured human airway epithelial cells in primary culture. Both agents caused a dose-dependent loss in the replicative ability of epithelial cells and at higher levels of exposure caused acute cytotoxicity as measured by release of lactate dehydrogenase. Differences were seen, however, between the agents' effects with regard to induction of DNA single strand breaks as measured by alkaline elution:; whereas single-strand breaks were detected in significant amounts at concentration of hydrogen peroxide that cause acute cytotoxicity, none were detected at any of the levels of ozone exposure examined. A difference was also seen in the ability of the iron chelator deferoxamine to protect cells from the effect of the two oxidants. Preincubation of cultures with deferoxamine appreciably attenuated the toxicity of hydrogen peroxide but not of ozone. These data suggest that ozone has significant toxic effects on bronchial epithelial cells not mediated through the generation of hydrogen peroxide or hydroxyl radical. Furthermore, the data indicate that the inhibiting action of ozone on cell replicative ability is not mediated through a mechanism related to DNA single strand breaks.     

Effect of inflammation on the proliferation of human gingival epithelial cells in vitro

The adaptive or pathologic responses of epithelial cells to inflammation are poorly characterized. The purpose of this study was to determine if epithelial cells cultured from clinically healthy and inflamed human gingival tissues express differences in proliferation rate and viability. Briefly, the inflammation status of individual donor sites from 101 patients was visually assessed at the time of periodontal surgery and categorized as either non-to-slightly inflamed, moderately inflamed, or severely inflamed. Discarded gingival tissues were then processed to obtain primary cell cultures, for which proliferation rates were determined by calculating the ratio of mean population doublings to the number of days required for cultures to become confluent. In general, the cells in the minimally inflamed group exhibited characteristics different than cells in the moderately and severely inflamed groups. Specifically, the cells obtained from clinical sites which exhibited no-to-slight inflammation had a significantly higher mean proliferation rate than cells in either the moderate inflammation group or the severe inflammation group. Based on trypan blue exclusion, the cells obtained from clinical sites which exhibited no-to-slight inflammation also were more viable than cells obtained from sites with moderate inflammation or severe inflammation. Microscopic evaluation showed morphological changes associated with increased inflammation. Cell cycle analysis by fluorescent-activated cell sorting (FACS) revealed a directly proportional relationship between the degree of inflammation and apoptosis, and a strong inversely proportional trend between the degree of inflammation and the numbers of cells undergoing mitosis. Taken together, these data suggest that epithelial cell proliferation and viability are inversely associated with the degree of gingival inflammation, once a putative "adaptive threshold" is exceeded. Elucidation of the underlying mechanisms will likely lead to improvements in clinical diagnosis and treatment.     

Regulation of metallothionein expression in human amnion epithelial and mesenchymal cells

OBJECTIVE: In this study the potential for metallothionein expression in amnion epithelial and mesenchymal cells in response to cadmium was evaluated. STUDY DESIGN: Levels of metallothionein messenger ribonucleic acid were evaluated in freshly separated amnion epithelial and mesenchymal cells and in amnion cells in culture. RESULTS: The levels of metallothionein messenger ribonucleic acid in human amnion mesenchymal cells freshly isolated after delivery of term pregnancies were greater than those in epithelial cells of the same tissue. The levels in mesenchymal cells in monolayer culture at confluence also were greater than those in confluent epithelial cells propagated from the same tissue. In response to treatment with cadmium (100 nmol/L to 50 micromol/L), which is inhaled in cigarette smoke, the levels of metallothionein messenger ribonucleic acid in both cell types increased markedly in a dose-dependent manner, but the level was greater in epithelial cells at all concentrations of cadmium chloride tested. With cadmium chloride (10 micromol/L), the level of metallothionein messenger ribonucleic acid increased by as much as 1000-fold in epithelial cells and 10-fold in mesenchymal cells compared with untreated (control) cells. Dexamethasone and tetradecanoyl phorbol acetate also acted to increase the levels in amnion epithelial and mesenchymal cells but not nearly to the levels effected by cadmium. CONCLUSION: These findings are indicative that metallothionein expression in amnion epithelial cells is exquisitely sensitive to cadmium in concentrations similar to those in amniotic fluid of pregnancies of women who smoke cigarettes. We hypothesize that increased levels of metallothionein in amniotic fluid and amnion epithelial cells will bind and thereby may limit the availability of copper to the Cu++-dependent enzyme lysyl oxidase in mesenchymal cells and thereby impair the cross-linking of interstitial collagens, which is effected by this enzyme.     

Following antigen challenge, T cells up-regulate cell surface expression of CD4 in vitro and in vivo

The low precursor frequency of Ag-specific T cells has raised significant barriers to studying the T cell response in vivo. We demonstrate that T cells up-regulate the cell surface expression of CD4 following Ag recognition, which identifies Ag-specific T cells in vitro and in vivo and allows their characterization. The CD4high cell subpopulation contains the Ag-specific population as indicated by Ag-induced proliferation and limiting dilution analyses. The use of the CD4high marker will allow analysis of the dynamics of the T cell immune response in vivo, the study of the suboptimal T cell response to Ag, and the identification of T cells which are reactive to known and unknown autoantigens.