title: [The endocytic routes of exogenous antigen in murine dendritic cells and macrophages].
abstract: OBJECTIVE
  To compare the endocytic routes of exogenous antigen in murine dendritic cells (DC) and macrophages.
  
  
  METHODS
  Murine bone marrow-derived DC and peritoneal macrophages were pulsed with HRP-5 nm colloidal gold for 10 minutes and chased for 0-120 minutes in culture medium. Intracellular distribution of 5 nm colloidal gold was explored by means of cellular enzymatic-chemistry of acidic phosphatase and MHC II cellular immunochemistry under electron microscope.
  
  
  RESULTS
  After 10 minutes pulse with HRP-5 nm colloidal gold and then 30 minutes of chase, most of HRP-5 nm colloidal gold internalized by DC entered into MHC II positive MIICs, but a little entered into acidic phosphatase-positive lysosomes. In contrast to DC, most of lysosomes of macrophages were accessed by HRP-5 nm colloidal gold, and a small portion of HRP-5 nm colloidal gold entered into MIICs. After 60 minutes of chase, 5 nm colloidal gold could hardly be seen within macrophages, whereas most of 5 nm colloidal gold retained in DC.
  
  
  CONCLUSIONS
  The endocytic route of exogenous antigen in DC apparently differs from that in macrophages. Most of antigens taken by macrophages enter into lysosomes within 30 minutes. In the case of DC, most of internalized antigens enter into MIICs, which may be related to their unique antigen-presenting function. In addition, macrophages seem to have more powerful capacity of scavenging exogenous antigen than DC.
authors.affiliation: Institute of Biophysics, Second Military Medical University, Shanghai, 200433.
authors.forename: Z
authors.initials: Z
authors.lastname: Xie
authors.forename: X
authors.initials: X
authors.lastname: Cao
authors.forename: W
authors.initials: W
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000166:cytology / Q000276:immunology*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D004705:Endocytosis; D017979:Gold Colloid / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006735:Horseradish Peroxidase / Q000276:immunology; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D017979:Gold Colloid; D000949:Histocompatibility Antigens Class II; D006735:Horseradish Peroxidase