3135 – CD34+CD19-CD22+ B-CELL PROGENITORS MIGHT UNDERLIE PHENOTYPIC ESCAPE IN PATIENTS TREATED WITH CD19-DIRECTED THERAPIES
نویسندگان
چکیده
CD19-directed immunotherapies have revolutionized the treatment of advanced B-ALL. Despite initial impressive rates complete remission (CR) many patients ultimately relapse. The fact that B-ALL successfully treated with T-cells eventually relapse, coupled early onset CD22 expression during B-cell development suggest pre-existing CD34+CD22+CD19- (pre)-leukemic cells could represent an “early progenitor origin-related” mechanism underlying phenotypic escape to immunotherapies. We demonstrate precedes CD19 development. CD34+CD19-CD22+ are found in diagnostic and relapsed BM samples ~70% patients, their frequency increases 2-fold CR after CD19-CAR T-cell therapy. Important, median before was 3-fold higher those who relapse immunotherapy (median follow-up 24 months). FISH analysis flow-sorted populations xenograft modeling revealed harbor genetic abnormalities present at diagnosis initiate leukemogenesis NSG mice. pre-leukemic progenitors underlie Our data reinforces ongoing clinical studies aimed simultaneously targeting as a strategy reduce CD19- relapses encourages implementation such CD34/CD19/CD22 panel flow cytometry laboratories for subsequent monitoring CD19-targeted
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ژورنال
عنوان ژورنال: Experimental Hematology
سال: 2022
ISSN: ['1873-2399', '0301-472X']
DOI: https://doi.org/10.1016/j.exphem.2022.07.191