title: Liver sinusoidal endothelial cells are insufficient to activate T cells.
abstract: Liver sinusoidal endothelial cells (LSEC) have been reported to express MHC class II, CD80, CD86, and CD11c and effectively stimulate naive T cells. Because dendritic cells (DC) are known to possess these characteristics, we sought to directly compare the phenotype and function of murine LSEC and DC. Nonparenchymal cells from C57BL/6 mice were obtained by collagenase digestion of the liver followed by density gradient centrifugation. From the enriched nonparenchymal cell fraction, LSEC (CD45(-)) were then isolated to 99% purity using immunomagnetic beads. Flow cytometric analysis of LSEC demonstrated high expression of CD31, von Willebrand factor, and FcgammaRs. However, unlike DC, LSEC had low or absent expression of MHC class II, CD86, and CD11c. LSEC demonstrated a high capacity for Ag uptake in vitro and in vivo. Although acetylated low-density lipoprotein uptake has been purported to be a specific function of LSEC, we found DC captured acetylated low-density lipoprotein to a similar extent in vivo. Consistent with their phenotype, LSEC were poor stimulators of allogeneic T cells. Furthermore, in the absence of exogenous costimulation, LSEC induced negligible proliferation of CD4(+) or CD8(+) TCR-transgenic T cells. Thus, contrary to previous reports, our data indicate that LSEC alone are insufficient to activate naive T cells.
authors.affiliation: Hepatobiliary Service, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 1002, USA.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Katz
authors.forename: Venu G
authors.initials: VG
authors.lastname: Pillarisetty
authors.forename: Joshua I
authors.initials: JI
authors.lastname: Bleier
authors.forename: Alaap B
authors.initials: AB
authors.lastname: Shah
authors.forename: Ronald P
authors.initials: RP
authors.lastname: DeMatteo
mesh_terms: D000818:Animals; D003713:Dendritic Cells / Q000502:physiology; D042783:Endothelial Cells / Q000502:physiology*; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis; D017493:Leukocyte Common Antigens / Q000032:analysis; D008099:Liver / Q000166:cytology* / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000949:Histocompatibility Antigens Class II; D017493:Leukocyte Common Antigens