COMPARISON OF IMMUNOFLUORESCENT AND IMMUNO ENZYMATIC TECHNIQUES FOR THE IMMUNETYPING OF ACUTE LYMPHOBLASTIC LEUKEMIAS

The aim of our study is to compare two different techniques (immunofleurescence and immunenzyme) which are being used for immunophenotyping of cells. Flow cytometer (FAGS) was used for immunfleurescense and APAAP procedure for immunoenzyme technique. 24 newly diagnosed acute lymphoblastic leukemia (ALL) patients were analyzed. CDS, CD7, CD10, CD22 and HLA-DR monoclonal antibodies were applied to leukemic blasts by either FACS or APAAP. Six cases were identified as T-ALL, 15 cases were as B ALL, by FACS and 6 cases were identified as T-ALL and 16 cases were as B-ALL by APAAP procedure. Sensitivity and specificity of APAAP procedure on T ALL were found 100%. But on B ALL in spite of sensitivity were 100%, specificity were found 89%. For evaluating the reason why specificity were low, B ALL cases were analyzed and it was found that in one case CD22 were negative by FACS but positive by APAAP. The cause of this finding may be related to membrane permeabilization procedure which is necessary for FACS to reveal intracytoplasmic antigens and that was not applied in our study. But in APAAP technique intracytoplasmic antigens are easily staining without any other procedure. As a result in acute leukemias if there is enough and appropriate monoclonal antibodies APAAP procedure is easy, cheap and can be applied in all hematology laboratories.