Cysteinyl leukotriene receptors in tonsillar B- and T-lymphocytes from children with obstructive sleep apnea.
OBJECTIVE
Cysteinyl leukotrienes have been implicated in the pathogenesis of adenotonsillar hypertrophy in children with obstructive sleep apnea (OSA). This study aimed to quantify the expression of cysteinyl leukotriene receptors (CysLT(1), CysLT(2)) by tonsillar lymphocyte subpopulations from children with OSA and to make comparisons to lymphocyte subpopulations from control subjects with recurrent tonsillitis (RT).


METHODS
Tonsillar tissue from children with OSA or RT was studied for CysLT(1) and CysLT(2) expression by RT-PCR, flow cytometry (FC), and immunofluorescence.


RESULTS
Ten children with OSA and 10 control subjects were recruited. In OSA participants, CysLT(1)+ fraction of small-size CD19+ B-lymphocytes was similar to the CysLT(1)+ CD3+ T-lymphocytes fraction (FC: 36.5 [16.5-55.4] vs. 14 [2.8-22.1]) (p>0.05) and higher than the CysLT(1)+ moderate/large-size CD19+ B-lymphocytes fraction (6.6 [1.5-14.4]) (p<0.01). Similar trends were recognized for CysLT(2). CysLT(1) and CysLT(2) immunoreactivity was detected by immunofluorescence in the tonsillar mantle zones (small B-lymphocytes) and the extrafollicular areas (T-lymphocytes). Compared to subjects with RT, children with OSA had significantly higher expression of CysLT(1) in small-size CD19+ B-lymphocytes (FC) and in CD3+ T-lymphocytes (RT-PCR and FC) (p<0.05).


CONCLUSIONS
Increased expression of leukotriene receptors by immunologically active tonsillar areas in children with OSA is a potential therapeutic target for pediatric sleep apnea.
Pediatric Pulmonology Unit, Sleep Disorders Laboratory, First Department of Pediatrics, National and Kapodistrian University of Athens School of Medicine and Aghia Sophia Children's Hospital, Athens 115.27, Greece.
Marina
M
Tsaoussoglou
Loukia
L
Lianou
Panagiotis
P
Maragozidis
Souzana
S
Hatzinikolaou
Maria
M
Mavromati
Nikolaos
N
Orologas
Polytimi
P
Panaghiotopoulou-Gartagani
George
G
Rassidakis
Nikolaos A A
NA
Balatsos
George
G
Chrousos
Athanasios G
AG
Kaditis
D001402:B-Lymphocytes / Q000737:chemistry*; D016022:Case-Control Studies; D002648:Child; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D014066:Palatine Tonsil / Q000737:chemistry* / Q000276:immunology; D017286:Polysomnography; D018077:Receptors, Leukotriene / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000276:immunology; D013601:T-Lymphocytes / Q000737:chemistry*; D014069:Tonsillitis / Q000276:immunology
D018077:Receptors, Leukotriene; C412375:cysteinyl leukotriene receptor 2; C083169:leukotriene D4 receptor