Because G-CSF/AMD3100 mobilization is problematic, specifically in patients with sickle cell disease, we used G-CSF-free mobilization regimens, the CXCR2-inhibitor tGroβ together with AMD3100 or AMD3100-tGroβ together with the VLA4 inhibitor WU-106. Here, CXCR2 is linked to sickle cell disease.