All procedures complied with the standards stated in the
Guide for the Care and Use of Laboratory Animals (Institute of Laboratory Animal Resources, National Academy of Sciences, Bethesda, Md, 1996) and were covered by ethical approvals from the Italian Ministry of Health and the United Kingdom Home Office. In 6- to 7-week-old male CD1 mice (Charles River Laboratories, Milan, Italy, and Morgate, UK) diabetes was induced by streptozotocin (Sigma), as described.25 (
link) Persistence of glycosuria of ≥10 g/L was checked over the duration of the experiments.
Four weeks after diabetes induction, bilateral hindlimb ischemia was induced by ligature of the proximal end of femoral arteries.13 (
link) At the same occasion, full-thickness wounds were created in the thigh dorsal skin of both legs using a sterile 5-mm-wide biopsy punch.26 (
link) The wounds were covered with type I collagen (Sigma) alone or collagen containing 2×10
4 CD133
+ or CD133
− cells. In separate experiments, wounds were covered with Extracel-HP hydrogel (Tebu-Bio, Le Perray en Yvelines, France),27 (
link) containing undiluted CD133
− or CD133
+ CCM with or without the Wnt inhibitor secreted frizzled-related protein (sFRP)-1, or CD133
+ CCM was applied together with neutralizing antibodies against VEGF, interleukin (IL)-6, or IL-8. Contralateral wounds were covered with hydrogel containing nonconditioned culture medium (NCCM). After surgery, animals were maintained in individual cages with food and water ad libitum and in a temperature and humidity-controlled environment. Clinical outcome was established by determining the rate of wound closure.26 (
link)
An expanded Materials and Methods section is available in the online data supplement at
http://circres.ahajournals.org.
Barcelos L.S., Duplaa C., Kränkel N., Graiani G., Invernici G., Katare R., Siragusa M., Meloni M., Campesi I., Monica M., Simm A., Campagnolo P., Mangialardi G., Stevanato L., Alessandri G., Emanueli C, & Madeddu P. (2009). Human CD133+ Progenitor Cells Promote the Healing of Diabetic Ischemic Ulcers by Paracrine Stimulation of Angiogenesis and Activation of Wnt Signaling. Circulation research, 104(9), 1095-1102.