Publications by authors named "Vladimir Zhogov"

3 Publications

  • Page 1 of 1

Relative expansion of CD19-negative very-early normal B-cell precursors in children with acute lymphoblastic leukaemia after CD19 targeting by blinatumomab and CAR-T cell therapy: implications for flow cytometric detection of minimal residual disease.

Br J Haematol 2021 May 14;193(3):602-612. Epub 2021 Mar 14.

National Research and Clinical Center for Pediatric Hematology, Oncology and Immunology, Moscow, Russian Federation.

CD19-directed treatment in B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) frequently leads to the downmodulation of targeted antigens. As multicolour flow cytometry (MFC) application for minimal/measurable residual disease (MRD) assessment in BCP-ALL is based on B-cell compartment study, CD19 loss could hamper MFC-MRD monitoring after blinatumomab or chimeric antigen receptor T-cell (CAR-T) therapy. The use of other antigens (CD22, CD10, CD79a, etc.) as B-lineage gating markers allows the identification of CD19-negative leukaemia, but it could also lead to misidentification of normal very-early CD19-negative BCPs as tumour blasts. In the current study, we summarized the results of the investigation of CD19-negative normal BCPs in 106 children with BCP-ALL who underwent CD19 targeting (blinatumomab, n = 64; CAR-T, n = 25; or both, n = 17). It was found that normal CD19-negative BCPs could be found in bone marrow after CD19-directed treatment more frequently than in healthy donors and children with BCP-ALL during chemotherapy or after stem cell transplantation. Analysis of the antigen expression profile revealed that normal CD19-negative BCPs could be mixed up with residual leukaemic blasts, even in bioinformatic analyses of MFC data. The results of our study should help to investigate MFC-MRD more accurately in patients who have undergone CD19-targeted therapy, even in cases with normal CD19-negative BCP expansion.
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May 2021

Chimerism evaluation in measurable residual disease-suspected cells isolated by flow cell sorting as a reliable tool for measurable residual disease verification in acute leukemia patients after allogeneic hematopoietic stem cell transplantation.

Cytometry B Clin Cytom 2020 Dec 28. Epub 2020 Dec 28.

Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia.

Background: The presence of minimal/measurable residual disease (MRD) before or after hematopoietic stem cell transplantation (HSCT) is known as a predictor of poor outcome in patients with acute myeloid (AML) or lymphoblastic (ALL) leukemia. When performed with multiparameter flow cytometry (MFC), assessment of residual leukemic cells after HSCT may be limited by therapy-induced shifts in the immunophenotype (e.g., loss of surface molecules used for therapeutic targeting). However, in such cases, questionable cells can be isolated and tested for hematopoietic chimerism to clarify their origin.

Methods: Questionable cell populations were detected during the MFC-based MRD monitoring of 52 follow-up bone marrow samples from 37 patients diagnosed with T cell neoplasms (n =14), B cell precursor ALL (n = 16), AML (n = 7). These cells (suspected leukemic or normal) were isolated by flow cell sorting and tested for hematopoietic chimerism by RTQ-PCR.

Results: The origin of cells was successfully identified in 96.15% of cases (n = 50), which helped to validate the results of MFC-based MRD monitoring.

Conclusions: We believe that a combination of MFC, cell sorting, and chimerism testing may help confirm or disprove MRD presence in complicated cases after HSCT.
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December 2020

Low-dose donor memory T-cell infusion after TCR alpha/beta depleted unrelated and haploidentical transplantation: results of a pilot trial.

Bone Marrow Transplant 2018 03 21;53(3):264-273. Epub 2017 Dec 21.

Department of Hematopoietic Stem Cell Transplantation, Dmitriy Rogachev National Center for Pediatric Hematology, Oncology and Immunology, Moscow, Russia.

Recovery of immunity is delayed in recipients of T-depleted grafts. Adoptive transfer of memory T-cells may improve immune response to common pathogens. A cohort of 53 patients with malignant (n = 36) and non-malignant conditions (n = 17) received TCR alpha/beta depleted grafts from haploidentical (n = 25) or MUD (n = 28) donors. Donor lymphocytes were depleted of CD45RA-positive cells. At a median of 48 days after transplantation, patients received DLI at 25 × 10/kg CD3 cells from haploidentical or 100 × 10/kg CD3 from MUD donors. Up to 3 doses of donor lymphocytes were administered at monthly intervals, escalating to 100 × 10/kg in haploidentical transplants and 300 × 10/kg in MUD transplants. At a median follow-up of 23 months, the cumulative incidence of de novo acute GVHD after DLI is 2% (1 of 43), while the rate of reactivation of preexisting aGVHD was 50% (5 of 10). The transplant-related mortality is 6%. The overall survival rates are 80% and 88% in malignant and non-malignant conditions, respectively. Among patients with absent CMV-specific immune reactivity at baseline (n = 31) expansion of CMV-specific T-cells was demonstrated in 20 (64.5%) within 100 days. Infusions of low dose donor memory T-lymphocytes are safe and constitute a simple measure to prevent infections in the setting of alpha/beta T cell-depleted transplantation.
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March 2018