FIG. 3.

Transduction of CD34-purified cells by CD105-LV^GFP is blocked by soluble CD105. The Fc-tagged extracellular part of CD105 (sCD105) or that of CD30 were added to CD105-LV^GFP or VSVG-LV^GFP in the indicated amounts. After 30 min incubation at 37°C the vector-protein mixtures were added to primary human CD34-purified cells at a MOI of 1 for CD105-LV^GFP and a MOI of 5 for VSVG-LV^GFP. Seventy-two hours later, the number of GFP-positive cells was determined by flow cytometry and the transduction efficiencies were calculated in relation to those obtained in absence of the soluble proteins. n=2; mean±SD.