CD34 Promotes Satellite Cell Motility and Entry into Proliferation to Facilitate Efficient Skeletal Muscle Regeneration

Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
Stem Cells (Impact Factor: 6.52). 12/2011; 29(12):2030-41. DOI: 10.1002/stem.759
Source: PubMed


Expression of the cell surface sialomucin CD34 is common to many adult stem cell types, including muscle satellite cells. However, no clear stem cell or regeneration-related phenotype has ever been reported in mice lacking CD34, and its function on these cells remains poorly understood. Here, we assess the functional role of CD34 on satellite cell-mediated muscle regeneration. We show that Cd34(-/-) mice, which have no obvious developmental phenotype, display a defect in muscle regeneration when challenged with either acute or chronic muscle injury. This regenerative defect is caused by impaired entry into proliferation and delayed myogenic progression. Consistent with the reported antiadhesive function of CD34, knockout satellite cells also show decreased motility along their host myofiber. Altogether, our results identify a role for CD34 in the poorly understood early steps of satellite cell activation and provide the first evidence that beyond being a stem cell marker, CD34 may play an important function in modulating stem cell activity.

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Available from: Kelly M Mcnagny, Dec 13, 2013
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    • "CD34 expression has also been shown to play a key role in satellite cell function. For instance, studies by Alfaro et al. have shown that CD34 expression promotes satellite cell proliferation and their ability to contribute to skeletal muscle regeneration [48]. It remains unknown whether the stage dependency is the main factor, or if it depends on environmental influences prior to implantation. "
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    • "The most common way to assess endometriotic lesion vascular development is to evaluate microvessel density using endothelial cell specific markers such as CD31 (Machado et al., 2010), von willebrand factor (Becker et al., 2005; Capobianco et al., 2011) or factor VIII (Dabrosin et al., 2002) followed by quantitative morphometry analysis to determine the area of the tissue covered by blood vessels. Some studies have also used CD34 as a specific endothelial cell marker in mice (Olivares et al., 2011; Ricci et al., 2011), however this approach could be problematic as CD34 is expressed by hematopoietic progenitor cells (Krause et al., 1994) mature leukocytes (Drew et al., 2002), and satellite cells (Alfaro et al., 2011) in mice. Vascular development has also been indirectly assessed by looking at VEGF expression in response to anti-angiogenic compounds (Xu et al., 2012; Ricci et al., 2011). "
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