title: Different thymosin Beta 4 immunoreactivity in foetal and adult gastrointestinal tract.
abstract: BACKGROUND
  Thymosin beta 4 (Tbeta(4)) is a member of beta-thymosins, a family of peptides that play essential roles in many cellular functions. A recent study from our group suggested a role for Tbeta(4) in the development of human salivary glands. The aim of this study was to analyze the expression of Tbeta(4) in the human gut during development, and in the adult.
  
  
  RESULTS
  Immunolocalization of Tbeta(4) was studied in autoptic samples of tongue, oesophagus, stomach, ileum, colon, liver and pancreas obtained from two human foetuses and two adults. Tbeta(4) appeared unevenly distributed, with marked differences between foetuses and adults. In the stomach, superficial epithelium was positive in foetuses and negative in adults. Ileal enterocytes were strongly positive in the adult and weakly positive in the foetuses. An increase in reactivity for Tbeta(4) was observed in superficial colon epithelium of adults as compared with the foetuses. Striking differences were found between foetal and adult liver: the former showed a very low reactivity for Tbeta(4) while in the adult we observed a strong reactivity in the vast majority of the hepatocytes. A peculiar pattern was found in the pancreas, with the strongest reactivity observed in foetal and adult islet cells.
  
  
  CONCLUSIONS
  Our data show a strong expression of Tbeta(4) in the human gut and in endocrine pancreas during development. The observed differential expression of Tbeta(4) suggests specific roles of the peptide in the gut of foetuses and adults. The observed heterogeneity of Tbeta(4) expression in the foetal life, ranging from a very rare detection in liver cells up to a diffuse reactivity in endocrine pancreas, should be taken into account when the role of Tbeta(4) in the development of human embryo is assessed. Future studies are needed to shed light on the link between Tbeta(4) and organogenesis.
authors.affiliation: Divisione di Anatomia Patologica, Dipartimento di Citomorfologia, University of Cagliari, Cagliari, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Nemolato
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cabras
authors.forename: Flaviana
authors.initials: F
authors.lastname: Cau
authors.forename: Mattia Umberto
authors.initials: MU
authors.lastname: Fanari
authors.forename: Daniela
authors.initials: D
authors.lastname: Fanni
authors.forename: Barbara
authors.initials: B
authors.lastname: Manconi
authors.forename: Irene
authors.initials: I
authors.lastname: Messana
authors.forename: Massimo
authors.initials: M
authors.lastname: Castagnola
authors.forename: Gavino
authors.initials: G
authors.lastname: Faa
mesh_terms: D000368:Aged; D001344:Autopsy; D020895:Enterocytes / Q000737:chemistry; D004848:Epithelium / Q000737:chemistry / Q000196:embryology; D005260:Female; D005753:Gastric Mucosa / Q000737:chemistry / Q000196:embryology; D041981:Gastrointestinal Tract / Q000737:chemistry* / Q000196:embryology*; D005865:Gestational Age; D022781:Hepatocytes / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D007515:Islets of Langerhans / Q000737:chemistry / Q000166:cytology / Q000196:embryology; D008099:Liver / Q000737:chemistry / Q000166:cytology / Q000196:embryology; D008297:Male; D013947:Thymosin / Q000032:analysis*; D000099201:Thymosin beta(4)
chemical_list: D013947:Thymosin; D000099201:Thymosin beta(4)