Kit allows the identification of CD34 + cells and link together their number with the identified known number of spheres discriminating between viable and non-viable cells and discarding false positives produced by non-specific staining of the isotype. Kit includes a vial of CD45 / CD34, a CD45/ IgG1 isotype control vial, counting tubes, a vial of 7-AAD and a bottle of lysis solution 10X.