Ozlem Keskin

Comparison of two methods for exhaled breath condensate collection

Background:  Exhaled breath condensate (EBC) is a noninvasive method to obtain samples from fluids lining the respiratory surfaces. Even though various methods and devices are now available, the relative efficiency of these methods for recovering airway mediators and characterizing EBC has not been established.

The effect of polymorphisms at the CD14 promoter and the TLR4 gene on asthma phenotypes in Turkish children with asthma

Background:  Endotoxin, with its potential to enhance type 1 immunity, is a significant player in the hygiene hypothesis. The combined effects of the genetic variants of various molecules in the endotoxin response pathway on asthma related phenotypes are largely unknown.

The effects of grass pollen allergoid immunotherapy on clinical and immunological parameters in children with allergic rhinitis

Allergoid immunotherapy is a new form of allergen immunotherapy allowing safe administration of high allergen doses. There is limited information on the effects of allergoid immunotherapy in children with allergic rhinitis. To investigate the immunological and clinical effects of allergoid immunotherapy in children with allergic rhinitis due to grass pollen allergy. Children with allergic rhinitis were assigned to allergoid immunotherapy (n = 27) or control (n = 26, no immunotherapy) groups. Children in the immunotherapy group received seven injections of grass pollen allergoid immunotherapy before grass pollen season and continued to receive maintenance immunotherapy for 27 months. All patients were offered a pharmacotherapy regimen to be used on demand during the pollen seasons. Clinical and laboratory parameters were compared between the immunotherapy and control groups. The rhinoconjunctivitis symptom‐medication score and asthma symptom score were lower in the immunotherapy group after 1 yr of maintenance immunotherapy (p < 0.01 for both). Skin test reactivity and nasal reactivity as determined by nasal provocation testing for grass pollen were significantly decreased after 1 yr of immunotherapy (p < 0.001 for both). The seasonal increase in bronchial reactivity and nasal lavage eosinophil cationic protein levels were prevented after the first year of immunotherapy (p < 0.05 for both). The seasonal increase in immunoglobulin (Ig)E decreased (p < 0.05) and grass‐specific IgG, IgG1 and IgG4 increased significantly already at the end of the seven‐injection build‐up therapy (p < 0.001, for all). Interleukin (IL)‐4 levels in the culture supernatants showed a steady decline from baseline at first and second year of immunotherapy (p < 0.001) but remained unchanged in the control group. Allergoid immunotherapy is an effective method in the treatment of grass pollen‐induced allergic rhinitis in children and prevents the seasonal increase in bronchial hyper‐reactivity. Changes in specific IgE and IgG levels and decreased IL‐4 production in peripheral blood mononuclear cell culture supernatants may account for the observed clinical effects.

ALOX5 promoter genotype, asthma severity and LTC4 production by eosinophils

Background:  The number of Sp1–Egr1 binding tandem repeats at the ALOX5 promoter influences gene transcription and may modify the response to anti‐leukotriene treatment. The relationship of ALOX5 variants to asthma severity and leukotriene production by eosinophils is unknown.

Do the leukotriene receptor antagonists work in children with grass pollen-induced allergic rhinitis?

Although cysteinyl‐leukotriene receptor antagonists were recently approved for use in allergic rhinitis (AR), there has been no study to date investigating their application in children. The aim was to evaluate whether montelukast provides any benefit in nasal allergen challenge‐induced symptoms in children, and whether it could improve the control provided by an antihistamine during pollen season. Two randomized studies, one a double‐blind, placebo‐controlled, nasal allergen challenge study and one an open‐label, cross‐over, parallel‐group clinical study, were performed in 18 (11.7 ± 0.7 years) and 32 children (10.5 ± 0.5 years), respectively, with grass pollen allergy. In the first study, the effect of a single dose of montelukast and its combination with loratadine were compared with placebo on nasal responses induced by allergen challenge. In the second study, the additive effect of montelukast to loratadine was tested in an open‐label cross‐over clinical study. In the challenge study, early‐phase and late‐phase nasal reactions peaked at 15 min and 4 h after the challenge respectively. During the early phase, combination improved total nasal symptoms (p = 0.004) during the first hour and sneezing (p = 0.012) at 15 min compared with placebo group. During the late phase, montelukast (p = 0.017) and combination (p = 0.011) caused less nasal obstruction at 4 h and combination caused less sneezing at 6 h (p = 0.015). In the clinical trial, montelukast provided protection on seasonal increase in pulmonary symptoms [0 (0, 14) vs. 6.5 (0, 27.7); p = 0.016] and on the decrease in FEF25−75 [−0.09 (−0.34, 0.17) vs. −0.28 (−0.66, 0.02); p = 0.002]. However, there was no improvement in nasal symptoms and flows. Although we showed protection against nasal challenge‐induced congestion with montelukast, we were not able to show the same in the clinical study possibly because of low pollen counts and mildness of the symptoms of the patients with AR. However, montelukast provided better control of pulmonary symptoms and protection from seasonal decrease in lung function, indicating its potential therapeutic benefit in children with AR.

The effect of CD14-C159T genotypes on the cytokine response to endotoxin by peripheral blood mononuclear cells from asthmatic children

BACKGROUND A C-T polymorphism at position 159 in the promoter of CD14 (C-159T) modulates the cellular response to endotoxin and significantly influences total IgE levels. The effect of this genetic variant on the cytokine response of the inflammatory cells is incompletely understood. OBJECTIVE To investigate the effects of CD14-C159T genotypes on the response to endotoxin by peripheral blood mononuclear cells (PBMCs) in children with asthma. METHODS The PBMCs from asthmatic children with the TT (n = 11) and CC (n = 11) genotypes at the CD14 promoter were cultured in the presence of endotoxin, 100 ng/mL; concanavalin A, 10 microg/mL; or medium alone. Concentrations of soluble CD14 (sCD14), interleukin (IL) 1beta, IL-4, IL-10, IL-12, IL-13, interferon-gamma, and transforming growth factor beta were determined in culture supernatants by enzyme-linked immunosorbent assay, and the transcriptional differences were evaluated using reverse-transcriptase polymerase chain reaction. RESULTS Under unstimulated conditions, children with the TT genotype produced higher levels of sCD14 into the culture supernatant compared with children with the CC genotype (P = .03, Mann Whitney U test). Both IL-10 and IL-1beta concentrations were significantly higher in culture supernatants of children with the TT genotype after endotoxin stimulation (P = .02 and P = .009, respectively, by analysis of covariance [ANCOVA]). Messenger RNA expression was consistent with the results of protein concentration for IL-10 and sCD14. Concanavalin A stimulation resulted in lower levels of IL-4 in children with the TT genotype (P = .02, ANCOVA). CONCLUSION The genotype at the CD14 promoter C159T locus may significantly influence the cytokine response of PBMCs obtained from asthmatic children. Differences in IL-10 and IL-4 production by alternative genotypes may contribute to the observed genotype effect on total IgE.

Is the CD14 C159T polymorphism effective in the development of secondary amyloidosis in Familial Mediterranean fever

The most important complication of FMF is the development of amyloidosis. It is more common in the eastern Mediterranean compared to the US. The individual response to endotoxin may have a significant effect on the development of amyloidosis in FMF patients. To investigate the association between CD14 promotor C-159T polymorphism and development of amyloidosis, one hundred and forty-six patients who had FMF and had not developed amyloidosis; 26 with FMF and secondary amyloidosis and 92 controls were genotyped at the CD14-C159T locus. There was no difference between the genotype distribution of FMF patients (CC 30.0%, CT 50.0%, TT 20.0%) and controls (CC 29.2%, CT 45.8%, TT 25%); or between FMF patients with amyloidosis (CC 30.8%, CT 53.8%, TT 15.4%) or without amyloidosis (CC 29.2%, CT 45.8%, TT 25%). Our study shows that the CD14-C159T polymorphism is not associated with FMF or development of amyloidosis in the population studied. The effect of the genetic variations in the endotoxin signaling pathway under different environmental conditions such as high and low endotoxin exposure remain to be determined.