[Role of CD44 on airway inflammatory response in rats with asthma].
OBJECTIVE
To study the role of cell adhesion molecule CD44 in the lung on airway inflammatory response in rats with asthma.


METHODS
Thirty-two Sprague-Dawley rats were randomly divided into normal control and asthma groups. Asthma was induced by repeated inhalation of ovalbulium. CD44 expression in the lung was detected by semi-quantitatively reverse transcription-polymerase chain reaction (RT-PCR) and immuno-histochemical staining 1 week and 2 weeks after ovalbulium challenge. Differential leukocytes (mononuclear phagocytes, neutrophils, eosinophils, and lymphocytes) in bronchoalveolar lavage fluid (BALF) were counted.


RESULTS
CD44 expression in the lung increased 1 week after ovalbulium challenge (<0.05) and increased more significantly 2 weeks after ovalbulium challenge (<0.01) compared with that in the control group. The percentages of lymphocytes and eosinophils in BALF increased, while the percentage of BALF mononuclear phagocytes decreased significantly 1 week and 2 weeks after ovalbulium challenge in the asthma group compared with those in the control group (<0.05). An increased percentage of neutrophils was found 1 week after ovalbulium challenge in the asthma group compared with the control group (<0.05). CD44 expression in the lung was positively correlated with the percentages of lymphocytes and eosinophils in BALF in the asthma group 1 week and 2 weeks after ovalbulium challenge, in contrast, lung CD44 expression was negatively correlated with the percentage of mononuclear phagocytes in the asthma group 1 week after ovalbulium challenge.


CONCLUSIONS
CD44 was over-expressed in the lung and closely related to inflammatory infiltration in rats with asthma. CD44 may play an important role in the development of airway inflammatory in asthma.
Li
Ling
L
Department of Respiratory, Wuxi Children's Hospital, Wuxi, Jiangsu 214023, China.
Yang
Li
L
Tang
Heng
H
Jin
Rui
R
D000818:Animals; D001249:Asthma / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D004804:Eosinophils / Q000502:physiology; D018960:Hyaluronan Receptors / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D007249:Inflammation / Q000209:etiology*; D008297:Male; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley
D018960:Hyaluronan Receptors; D012333:RNA, Messenger