title: Trafficking of recirculating lymphocytes in the rat liver: rapid transmigration into the portal area and then to the hepatic lymph.
abstract: BACKGROUND
  We have investigated how recirculating lymphocytes patrol the liver in a normal steady state.
  
  
  METHODS
  Thoracic duct lymphocytes of congeneic rats were intravenously transferred to host rats and donor cell trafficking in the liver and hepatic lymph was examined. Host hepatic lymph nodes (HLNs) were selectively removed, which allowed liver-derived donor cells to collect in the thoracic duct without transit in the intervening HLNs.
  
  
  RESULTS
  The number of donor cells in the thoracic duct lymph significantly increased over the baseline 3, 5 and 11 h after transfer in the HLN-removed, non-pretreated, and HLN-ligated (in which a lymph efflux was blocked) groups, respectively. Histologically, donor cells appeared in the portal area from 0.5 h after transfer and frequently attached to the basal lamina of portal vein both externally and internally. Three hours after transfer, a few donor cells appeared in the subcapsular sinus of HLNs.
  
  
  CONCLUSIONS
  The minimal transit time of rat recirculating lymphocytes is 3-4 h in the liver and 5-8 h in the hepatic LNs, in a normal steady state. Recirculating lymphocytes might transmigrate through the portal vein as well as the sinusoid in the periportal zone. This rapid transit might enable an efficient surveillance of the liver portal area by the recirculating lymphocytes.
authors.affiliation: Department of Anatomy (Macro), and SORST, Dokkyo Medical University, Tochigi 321-0293, Japan.
authors.forename: Xue-Dong
authors.initials: XD
authors.lastname: Xu
authors.forename: Hisashi
authors.initials: H
authors.lastname: Ueta
authors.forename: Shu
authors.initials: S
authors.lastname: Zhou
authors.forename: Changde
authors.initials: C
authors.lastname: Shi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Koga
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Ushiki
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Matsuno
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000276:immunology*; D005434:Flow Cytometry; D007150:Immunohistochemistry; D007700:Kinetics; D008099:Liver / Q000276:immunology*; D008196:Lymph / Q000166:cytology* / Q000276:immunology; D008197:Lymph Node Excision; D017710:Lymphocyte Transfusion; D008214:Lymphocytes / Q000276:immunology* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D051381:Rats; D018709:Statistics, Nonparametric; D013897:Thoracic Duct / Q000276:immunology*; D013997:Time Factors