Expression of the cell surface protein CD146 (which is involved in adhesion, migration, and mesenchymal differentiation) on CXCL12 co-expressing pericytes seems to be important for the MSPC-aided in vitro propagation [40,614,615] and/or in vivo engraftment of clonal MDS cells [276]. Here, CXCL12 is linked to myelodysplastic syndrome.