Shereen El Shorbagy

Detection of Minimal Residual Disease in Childhood B-Acute LymphoblasticLeukemia by 4-Color Flow Cytometry

Monitoring of minimal residual disease (MRD) is today considered the most powerful predictor of outcome in acute leukemias, including acute lymphoblastic leukemia (ALL). The study aimed to determine whether panel of antibodies combination are more suitable than others for detection of MRD in Childhood B-lineage ALL. Eighty four (84) patients of ALL (B-lineage subtype) were enrolled in this study. Normal template for B. Cell precursors were been established in 15 control Patients by using 4 panels of monoclonal Abs (Mo Abs), {CD22, CD45, CD58 and CD97 in combination with CD10, CD19, CD34}. At diagnosis CD22 having the lowest incidence expression between the patients in 50% only, but CD45, CD58, and CD97 were expressed in 80.9%, 52.3% and 92.8% respectively. Analysis of MRD was performed for each Mo Abs combination at day 0 and day 14 post induction of chemotherapy by 4-color flow cytometer (FCM). The incidence of MRD were 61.9%, 70.6%, 60.0% and 55.5% for CD22,CD45,CD58 and CD97 respectively. Seventy-six from total 84 cases studied (90.0%) had at least one LAIP. Of these, 22 (29.0%) had only one LAIP and 54 cases (71.0%) had ≥ 2 LAIPS Conclusion: In the B-ALL patients (CD10/CD19/CD34/CD45)+ and (CD10/CD19/CD34/CD97)+, represented the highest incidence markers expression of leukemic cells with a significant correlation with blasts count, so its the more specific for MRD detection.