CD4+ CD25high Regulatory T Cells in Newly Diagnosed Patients with Acute Myeloid Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2835-2835
Author(s):  
Miroslaw J. Szczepanski ◽  
Laura Strauss ◽  
Malgorzata Czystowska ◽  
Marta Szajnik ◽  
Ann Welsh ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Fas Ligand ◽  
Hematologic Malignancies ◽  
Newly Diagnosed ◽  
Therapeutic Implications ◽  
Healthy Donors ◽  
Acute Myeloid

Abstract Regulatory CD4+CD25+ T cells (T reg) are critical regulators of immune tolerance. Increasing evidence supports the existence of elevated numbers of regulatory T cells in cancer patients. Although the increase of T cells seems to be a characteristic feature in most tumors the functional role of Treg, especially in patients with hematologic malignancies, has been less well defined. Mutlicolor flow cytomerty was used to investigated the frequency and phenotype of CD4+ CD25high T cells in the peripheral blood of thirty seven newly diagnosed acute myeloid leukemia (AML) patients (prior to any treatment) and thirty one healthy donors. The suppressive function of Treg was evaluated using CFSE-labeled fresh autologous CD4+CD25− T cells activated with an anti-CD3 antibody as responders. The percentage of circulating CD4+ CD25high Treg was higher (p < 0.0001) in the AML patients (2.9 ± 0.3%, range 0.1–7%) compared to healthy donors (0.4 ± 0.02%, range 0.1–1%). Percentages of T reg expressing Foxp3, CTLA-4, CD45 RO, Fas ligand (CD95) and GITR were significantly elevated in the circulation of AML patients compared to healthy donors: Foxp3 60vs32% p<0.001, CTLA-4 47vs21% p<0.01, CD45 RO 81vs53% p<0.002, Fas ligand 23vs4% p<0.001, GITR 65vs25% p<0.001. Suppression mediated by T reg co-incubated with proliferating autologous responders was also significantly higher (p<0.001) in AML than that mediated by control T reg (75 ± 6% vs 12% ± 4%). These results indicate that T reg accumulate in the periphery of patients with AML and mediate vigorous suppression. Modulation of the Treg suppressive activity, especially during the post-induction period, in AML patients may have therapeutic implications.

Mechanisms of Suppression Used by Regulatory T Cells in Patients Newly Diagnosed with Acute Myeloid Leukemia

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2938-2938 ◽  
Author(s):  
Miroslaw J Szczepanski ◽  
Marta Szajnik ◽  
Malgorzata Czystowska ◽  
Magis Mandapathil ◽  
Ann Welsh ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Neutralizing Antibodies ◽  
Hematologic Malignancies ◽  
Cell Contact ◽  
Newly Diagnosed ◽  
Acute Myeloid

Abstract An elevated frequency of CD4+CD25high regulatory T cells (Treg) has been reported in the peripheral blood in patients with various solid tumors and hematologic malignancies. Although the increase in Treg seems to be a characteristic feature of most tumors, the functional role of Treg and the mechanisms of suppression, especially in patients with hematologic malignancies, have been less well defined. We investigated Treg-mediated suppression and the responsible mechanisms in thirty newly diagnosed acute myeloid leukemia (AML) patients prior to any treatment and twenty five healthy donors (NC). The percentage of circulating CD4+ CD25high Treg was higher (p &lt;0.0001) in the AML patients (4.5 ±0.2%, range 1.7–8.2%) compared to NC (1.5 ± 0.08%, range 0.9–3.1 %). To evaluate the suppressive function, CD4+CD25high T cells (S) were co-cultured with sorted, CFSE-labeled autologous CD4+CD25high T cells (R) at different S/R ratios. Suppression mediated by Treg co-incubated with proliferating autologous responders was significantly higher (p&lt;0.001) in AML than that mediated by control Treg. To evaluate the role of cytokines produced by Treg in suppression and a need for cell-to- cell contact, transwell analysis of S/R co-cultures was performed. Co-incubation in the presence of transwell inserts (TRI) resulted in significant reduction of suppression (p&lt;0.05), and the addition of neutralizing antibodies to IL-10 and TGF-β1 in the presence of TRI further decreased suppression mediated by Treg. These data suggest that both immunoinhibitory cytokine production and cell-to-cell contact are necessary for suppression. To explore other potential mechanisms of Treg suppression, we evaluated the expression by Treg of ectonucleotidases CD39 and CD73 and the capability of Treg to produce adenosine. CD4+CD25high T cells of AML patients had higher expression (p&lt;0.01) of CD39 and more efficiently hydrolyzed ATP to adenosine relative to Treg in NC. These data indicate that various mechanisms of suppression may be utilized by Treg in patients with AML. The increase frequency of Treg mediating potent suppression by various mechanisms is likely to play a role in host anti-tumor immune responses. Therefore, modulation of the frequency and functions of Treg might provide new immunotherapeutic approaches in AML.

scholarly journals High incidence of alternatively spliced forms of deoxycytidine kinase in patients with resistant acute myeloid leukemia

Blood ◽  
2000 ◽  
Vol 96 (4) ◽  
pp. 1517-1524 ◽  
Author(s):  
Marjan J. T. Veuger ◽  
M. Willy Honders ◽  
Jim E. Landegent ◽  
Roel Willemze ◽  
Renée M. Y. Barge
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Messenger Rna ◽  
Myeloid Leukemia ◽  
Deoxycytidine Kinase ◽  
Wild Type ◽  
Healthy Donors ◽  
Alternatively Spliced ◽  
Acute Myeloid

Deficiency of functional deoxycytidine kinase (dCK) is a common characteristic for in vitro resistance to cytarabine (AraC). To investigate whether dCK is also a target for induction of AraC resistance in patients with acute myeloid leukemia (AML), we determined dCK messenger RNA (mRNA) expression in (purified) leukemic blasts and phytohemagglutinin-stimulated T cells (PHA T cells) from patients with chemotherapy-sensitive and chemotherapy-resistant AML. In control samples from healthy donors (PHA T cells and bone marrow), only wild-type dCK complementary DNA (cDNA) was amplified. Also, in (purified) leukemic blasts from patients with sensitive AML, only wild-type dCK cDNAs were observed. These cDNAs coded for active dCK proteins in vitro. However, in 7 of 12 (purified) leukemic blast samples from patients with resistant AML, additional polymerase chain reaction fragments with a deletion of exon 5, exons 3 to 4, exons 3 to 6, or exons 2 to 6 were detected in coexpression with wild-type dCK. Deletion of exons 3 to 6 was also identified in 6 of 12 PHA T cells generated from the patients with resistant AML. The deleted dCK mRNAs were formed by alternative splicing and did code for inactive dCK proteins in vitro. These findings suggest that the presence of inactive, alternatively spliced dCK mRNA transcripts in resistant AML blasts may contribute to the process of AraC resistance in patients with AML.

scholarly journals Midostaurin reduces Regulatory T cells markers in Acute Myeloid Leukemia

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Lucas Gutierrez ◽  
Miran Jang ◽  
Tian Zhang ◽  
Mojtaba Akhtari ◽  
Houda Alachkar
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Acute Myeloid

scholarly journals High incidence of alternatively spliced forms of deoxycytidine kinase in patients with resistant acute myeloid leukemia

Blood ◽  
2000 ◽  
Vol 96 (4) ◽  
pp. 1517-1524 ◽  
Author(s):  
Marjan J. T. Veuger ◽  
M. Willy Honders ◽  
Jim E. Landegent ◽  
Roel Willemze ◽  
Renée M. Y. Barge
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Messenger Rna ◽  
Myeloid Leukemia ◽  
Deoxycytidine Kinase ◽  
Wild Type ◽  
Healthy Donors ◽  
Alternatively Spliced ◽  
Acute Myeloid

Abstract Deficiency of functional deoxycytidine kinase (dCK) is a common characteristic for in vitro resistance to cytarabine (AraC). To investigate whether dCK is also a target for induction of AraC resistance in patients with acute myeloid leukemia (AML), we determined dCK messenger RNA (mRNA) expression in (purified) leukemic blasts and phytohemagglutinin-stimulated T cells (PHA T cells) from patients with chemotherapy-sensitive and chemotherapy-resistant AML. In control samples from healthy donors (PHA T cells and bone marrow), only wild-type dCK complementary DNA (cDNA) was amplified. Also, in (purified) leukemic blasts from patients with sensitive AML, only wild-type dCK cDNAs were observed. These cDNAs coded for active dCK proteins in vitro. However, in 7 of 12 (purified) leukemic blast samples from patients with resistant AML, additional polymerase chain reaction fragments with a deletion of exon 5, exons 3 to 4, exons 3 to 6, or exons 2 to 6 were detected in coexpression with wild-type dCK. Deletion of exons 3 to 6 was also identified in 6 of 12 PHA T cells generated from the patients with resistant AML. The deleted dCK mRNAs were formed by alternative splicing and did code for inactive dCK proteins in vitro. These findings suggest that the presence of inactive, alternatively spliced dCK mRNA transcripts in resistant AML blasts may contribute to the process of AraC resistance in patients with AML.

Elevated frequencies of CD4+CD25+CD127lo regulatory T cells is associated to poor prognosis in patients with acute myeloid leukemia

2011 ◽  
Vol 129 (6) ◽  
pp. 1373-1381 ◽  
Author(s):  
Zhang Shenghui ◽  
Han Yixiang ◽  
Wu Jianbo ◽  
Yu Kang ◽  
Bi Laixi ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Poor Prognosis ◽  
Acute Myeloid

scholarly journals PD-L1 Is Expressed and Promotes the Expansion of Regulatory T Cells in Acute Myeloid Leukemia

2020 ◽  
Vol 11 ◽  
Author(s):  
Yuqing Dong ◽  
Yixiang Han ◽  
Yisha Huang ◽  
Songfu Jiang ◽  
Ziyang Huang ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Acute Myeloid

Up-regulation of regulatory T cells, CD200 and TIM3 expression in cytogenetically normal acute myeloid leukemia

2018 ◽  
Vol 22 (3) ◽  
pp. 587-595 ◽  
Author(s):  
Asmaa M. Zahran ◽  
Mostafa F. Mohammed Saleh ◽  
Mona M. Sayed ◽  
Amal Rayan ◽  
Arwa Mohammed Ali ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Regulatory T Cells ◽  
Myeloid Leukemia ◽  
Acute Myeloid

TCRab Deficient CAR T-Cells Targeting CD123: An Allogeneic Approach of Adoptive Immunotherapy for the Treatment of Acute Myeloid Leukemia (AML)

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2555-2555 ◽  
Author(s):  
Roman Galetto ◽  
Céline Lebuhotel ◽  
Agnès Gouble ◽  
Nuria Mencia-Trinchant ◽  
Cruz M Nicole ◽  
...  
Keyword(s):  
T Cells ◽  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Surface Expression ◽  
Car T Cells ◽  
Healthy Donors ◽  
Car T ◽  
Acute Myeloid

Abstract The remissions achieved using autologous T-cells expressing chimeric antigen receptors (CARs) in patients with advanced B cell leukemia and lymphomas have encouraged the use of CAR technology to treat different types of cancers by targeting distinct tumor-specific antigens. Since the current autologous approach utilizes CAR T-cells manufactured on a "per patient" basis, we propose an alternative approach based on the use of a standardized platform for manufacturing T-cells from third-party healthy donors to generate allogeneic "off-the-shelf" CAR T-cell-based frozen products. In the present work we have adapted this allogeneic platform to the production of T-cells targeting CD123, the transmembrane alpha chain of the interleukin-3 receptor, which is expressed on tumor cells from the majority of patients with Acute Myeloid Leukemia (AML). Multiple antigen recognition domains were screened in the context of different CAR architectures to identify candidates displaying activity against cells expressing variable levels of the CD123 antigen. The three lead candidates were tested in an orthotopic human AML cell line xenograft mouse model. From the three candidates that displayed comparable activity in vitro, we found two candidates capable of eradicating tumor cells in vivo with high efficiency. Subsequently, Transcription Activator-Like Effector Nuclease (TALEN) gene editing technology was used to inactivate the TCRα constant (TRAC) gene, eliminating the potential for engineered T-cells to mediate Graft versus Host Disease (GvHD). Editing of the TRAC gene can be achieved at high frequencies, and allows efficient amplification of TCR-deficient T-cells that no longer mediate alloreactivity in a xeno-GvHD mouse model. In addition, we show that TCR-deficient T-cells display equivalent in vitro and in vivo activity to non-edited T-cells expressing the same CAR. We have performed an initial evaluation of the expression of CD123 in AML patients and found an average cell surface expression of CD123 was of 67% in leukemic blasts (95% CI 48-82), 71% in CD34+CD38+ cells (95% CI 56-86), and 64% in CD34+CD38- (95% CI 41-87). Importantly, we have found that CD123 surface expression persists in CD34+CD38-CD90- cells after therapy in at least 20% of patients in remission (n=25), thus emphasizing the relevance of the target. Currently, the sensitivity of primary AML cells to CAR T-cells is being tested. Finally, we will also present our large scale manufacturing process of allogeneic CD123 specific T-cells from healthy donors, showing the feasibility for this off-the-shelf T-cell product that could be available for administration to a large number of AML patients. Disclosures Galetto: Cellectis SA: Employment. Lebuhotel:Cellectis SA: Employment. Gouble:Cellectis SA: Employment. Smith:Cellectis: Employment, Patents & Royalties.

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