MULTIPARAMETRIC ANALYSIS FOR THE ENUMERATION OF CD34(-MARROW AND STIMULATED PERIPHERAL-BLOOD() CELLS FROM BONE)

Determination of CD34(+) cells was performed in bone marrow and G-CSF mobilised peripheral blood samples. We adopted three different protoco ls of analysis: the Milan/Mulhouse protocol, the ISHAGE guidelines for CD34(+) cell determination and our own protocol based upon the use of PAINT-A-GATE(PRO(TM)) software analysis program. An excellent correla tion was demonstrated between the three methods (r(2) greater than or equal to 0.98); however the analysis of variance showed a statisticall y significant difference between the results generated with the three methods (P=0.001). The differences between the three procedures are di scussed with a special focus on the value of CD34(+dim) cells and the role of CD45 in the setting of a double staining. We have in fact iden tified a minor subset (CD34(+)CD38(+)CD45(-)) which would go unrecogni sed based upon its CD45 negativity.