title: Rat cerebral mast cells undergo phenotypic changes during development.
abstract: The evolution of rat cerebral mast cell phenotype during development was studied using antibodies against the granule chymases, rat mast cell protease I (RMCP-I) and rat mast cell protease II (RMCP-II) and their gene transcripts, as markers for serosal and mucosal mast cells, respectively. In situ hybridization using specific oligoprobes for RMCP-II permitted visualization of RMCP-II mRNA-containing cells as early as day 15 of embryonic development (E15). From E19 to day 4 postpartum (D4) their number increased whilst they migrated from the pia mater to the choroid fissure; at D8 cells expressing RMCP-II gene transcripts were no longer observed. The 3'-end untranslated nucleotide sequence of the RMCP-I cDNA was established in order to design selective cDNA probes for Northern blot analysis of both enzymes. Northern blot analysis revealed a strong expression of RMCP-I and RMCP-II mRNAs at D2. At D4, RMCP-I mRNA expression was still high, whereas that of RMCP-II was decreased. In adult brain, mRNA expression for both proteases was low, but detectable. Quantification of both proteases by ELISA showed that, from E19 to D4, levels of RMCP-II were maximal at E19 and remained constant until D4, whereas RMCP-I increased as a function of age. Thereafter, levels of both proteases decreased progressively, but were still present in the adult brain, with RMCP-II being uniformly distributed and RMCP-I concentrated in the thalamus. Immunohistochemical staining showed RMCP-II-immunoreactive cells within the pia mater at E19; on D2 and D4, cells with both RMCP-I and RMCP-II immunoreactivities were found within the choroid fissure and from D8, only RMCP-I-immunoreactive mast cells were observed. In the thalamus of adult rats, the latter had a perivascular localization. This study shows that in the adult, both types of mast cells are present, although in small numbers, except for RMCP-I-immunoreactive mast cells which are abundant in the thalamus. The changes in the number and phenotype of cerebral mast cells may result from the influence of a number of growth factors during development.
authors.affiliation: Laboratoire de Physiologie, Faculté de Pharmacie, Université René Descartes, Paris, France.
authors.forename: V
authors.initials: V
authors.lastname: Dimitriadou
authors.forename: A
authors.initials: A
authors.lastname: Rouleau
authors.forename: M D
authors.initials: MD
authors.lastname: Tuong
authors.forename: X
authors.initials: X
authors.lastname: Ligneau
authors.forename: G F
authors.initials: GF
authors.lastname: Newlands
authors.forename: H R
authors.initials: HR
authors.lastname: Miller
authors.forename: J C
authors.initials: JC
authors.lastname: Schwartz
authors.forename: M
authors.initials: M
authors.lastname: Garbarg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015415:Biomarkers; D015152:Blotting, Northern; D002454:Cell Differentiation / Q000502:physiology; D002540:Cerebral Cortex / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D053818:Chymases; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D007150:Immunohistochemistry; D016130:Immunophenotyping; D017403:In Situ Hybridization; D008297:Male; D008407:Mast Cells / Q000166:cytology* / Q000201:enzymology / Q000276:immunology; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D012697:Serine Endopeptidases; C057818:cytotoxic T lymphocyte-specific serine protease; D053818:Chymases