Neointimal formation by circulating bone marrow cells.
The origin of smooth muscle cells involved in vascular healing was examined. Eighteen C57BL/6 (Ly 5.2) female mice underwent whole body irradiation followed by transfusion with 106 bone nucleated marrow cells from congenic (Ly 5.1) male donors. Successful repopulation by donor marrow was demonstrated after 4 weeks by flow cytometry with FITC-conjugated A20.1/Ly 5.1 monoclonal antibody. The iliac artery of six of the chimeric mice was scratch-injured by five passes of a probe, causing severe medial damage. After 4 weeks the arterial lumen was obliterated by a cell-rich neointima, with alpha-smooth muscle actin-containing cells present around the residual lumen. Approximately half of these cells were of male donor origin, as evidenced by in situ hybridization with a Y chromosome-specific probe. An organized arterial thrombus was formed in the remaining 12 chimeric mice by inserting an 8-0 silk suture into the left common carotid artery. Donor cells staining with alpha-smooth muscle actin were found in those arteries sustaining serious damage but not in arteries with minimal damage. Our results suggest that bone marrow-derived cells are recruited in vascular healing as a complementary source of smooth muscle-like cells when the media is severely damaged and few resident smooth muscle cells are available to effect repair.
Campbell
J H
JH
Centre for Research in Vascular Biology, University of Queensland, Brisbane, Australia. julie.campbell@mailbox.uq.edu.au
Han
C L
CL
Campbell
G R
GR
D001161:Arteriosclerosis / Q000473:pathology / Q000503:physiopathology; D001854:Bone Marrow Cells / Q000166:cytology* / Q000473:pathology; D002465:Cell Movement; D006801:Humans; D017539:Tunica Intima / Q000166:cytology* / Q000473:pathology; D014947:Wounds and Injuries / Q000473:pathology / Q000503:physiopathology