[Expression of pulmonary surfactant-associated protein D and its significance in human fetal lung].
OBJECTIVE
To observe the expression of pulmonary surfactant-associated protein D (SP-D) during human fetal lung development.


METHODS
Human fetal lung tissues from 11- to 36-week-old fetuses were assayed for lung maturity with HE staining and SP-D expression by means of immunohistochemistry.


RESULTS
SP-D expression was located in the bronchial epithelium and alveolar epithelial type II cells(AEC II) of the lung tissues since the 12th week, and gradually increased during the canalicular to saccular stages with fetal development, at the point of which SP-D-positivity began a shift from the proximal bronchial epithelium to AEC II , and evidently located in the alveoli from the advanced stage of lung development till postnatal stage.


CONCLUSIONS
SP-D expression gradually intensifies with the maturation of the fetal lungs, and SP-D-positive cells begin to be detected in the bronchial epithelium and finally in AEC II.
Chen
Yue
Y
Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China. cwn2@sohu.com
DU
Jiang
J
Zhao
Qian
Q
Feng
Zhi-Chun
ZC
D000328:Adult; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D005333:Fetus; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000196:embryology* / Q000378:metabolism*; D011247:Pregnancy; D011650:Pulmonary Alveoli / Q000166:cytology / Q000378:metabolism; D037663:Pulmonary Surfactant-Associated Protein D / Q000096:biosynthesis*; D011663:Pulmonary Surfactants
D037663:Pulmonary Surfactant-Associated Protein D; D011663:Pulmonary Surfactants