title: S-100 immunoreactivity in pulmonary neuroendocrine cells of newborn infants.
abstract: S-100 protein was demonstrated by immunohistochemical techniques in occasional solitary neuroendocrine cells of the lungs of newborn infants. The S-100 immunoreactivity was located in both the nucleus and the cytoplasm; its distribution in the cytoplasm was diffuse, there being no differences in staining intensity between the apical and basal poles. This homogeneus distribution of immunoreactivity argues against the S-100 being located in the dense-core granules, since these organelles are concentrated towards the basal pole. Double immunohistochemical techniques revealed that S-100 immunoreactive cells were also chromogranin A immunoreactive. Our results indicate that the S-100 positive population is a subset of the chromogranin A positive neuroendocrine cells. S-100 immunoreactivity was not detected in neuroepithelial bodies.
authors.affiliation: Department of Morphological Sciences, Faculty of Medicine, University of Santiago de Compostela, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Gallego
authors.forename: T
authors.initials: T
authors.lastname: García-Caballero
authors.forename: M
authors.initials: M
authors.lastname: Fraga
authors.forename: A
authors.initials: A
authors.lastname: Beiras
mesh_terms: D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007231:Infant, Newborn / Q000378:metabolism*; D008168:Lung / Q000737:chemistry* / Q000166:cytology; D008297:Male; D009490:Neurosecretory Systems / Q000737:chemistry* / Q000166:cytology*; D009418:S100 Proteins / Q000032:analysis* / Q000276:immunology
chemical_list: D009418:S100 Proteins