Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 558
Filtrar
1.
Ann Lab Med ; 39(5): 430-437, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31037861

RESUMO

BACKGROUND: T cell immunophenotypes in patients with hemophagocytic lymphohistiocytosis (HLH) have been described. Downregulation of CD5 or CD7 on T cells has been reported in patients with Epstein-Barr virus (EBV)-positive HLH. As the utility of T cell immunophenotypes as an adjunctive diagnostic or a prognostic marker for HLH has not been evaluated, we analyzed T cell immunophenotypes in HLH patients for this purpose. METHODS: We classified 45 HLH patients into three subgroups: EBV-positive HLH (N=27), EBV-negative secondary HLH (N=15), and familial HLH (N=3). We retrospectively characterized downregulation patterns of CD5 or CD7 on activated T cells, using flow cytometry. Overall survival was estimated using Kaplan-Meier curves and compared using the log-rank test. RESULTS: An aberrant immunophenotype, including CD5 and/or CD7 downregulation on T cells, was observed in 55.6% (15/27) of the EBV-positive HLH patients and 100% of the familial HLH (3/3). Only one (1/15, 6.7%) patient with EBV-negative secondary HLH showed an aberrant loss of CD7 antigen on CD8+ T cells. The presence of an aberrant T cell immunophenotype was not related to overall survival in EBV-positive HLH and EBV-negative secondary HLH patients. CONCLUSIONS: An aberrant T cell immunophenotype may assist in discriminating EBV-negative secondary HLH and EBV-positive HLH. However, it may not be useful as a prognostic marker.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Linfo-Histiocitose Hemofagocítica/diagnóstico , Adolescente , Adulto , Idoso , Antígenos CD7/metabolismo , Antígenos CD5/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Imunofenotipagem , Lactente , Estimativa de Kaplan-Meier , Linfo-Histiocitose Hemofagocítica/imunologia , Linfo-Histiocitose Hemofagocítica/mortalidade , Linfo-Histiocitose Hemofagocítica/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
2.
Front Immunol ; 10: 81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30761146

RESUMO

HIV-1 causes the loss of CD4+ T cells via depletion or impairment of their production. The latter involves infection of thymocytes, but the involvement of hematopoietic CD34+ cells remains unclear even though HIV-positive patients frequently manifest myelosuppression. In order to have a closer look at the impact of HIV-1 on T-lineage differentiation, this study utilized the OP9-DL1 coculture system, which supports in vitro T-lineage differentiation of human hematopoietic stem/progenitor cells. In the newly developed in vitro OP9-DL1/HIV-1 model, cord-derived CD34+ cells were infected with CXCR4-tropic HIV-1NL4-3 and cocultured. The HIV-infected cocultures exhibited reduced CD4+ T-cell growth at weeks 3-5 post infection compared to autologous uninfected cocultures. Further assays and analyses revealed that CD34+CD7+CXCR4+ cells can be quickly depleted as early as 1 week after infection of the subset, and this was accompanied by the emergence of rare CD34+CD7+CD4+ cells. A subsequent theoretical model analysis suggested potential influence of HIV-1 on the differentiation rate or death rate of lymphoid progenitor cells. These results indicate that CXCR4-tropic HIV-1 strains may impact the dynamics of CD34+CD7+ lymphoid progenitor cell pools, presumably leading to impaired T-cell production potential.


Assuntos
Antígenos CD34/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular , HIV-1/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células Estromais/metabolismo , Síndrome de Imunodeficiência Adquirida/metabolismo , Animais , Antígenos CD7/metabolismo , Linhagem da Célula , Técnicas de Cocultura , Sangue Fetal/citologia , Células HEK293 , HIV-1/genética , Humanos , Camundongos , Modelos Biológicos , Receptores CXCR4/metabolismo
3.
Mol Ther ; 27(1): 272-280, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30391141

RESUMO

Chimeric antigen receptor (CAR) T cell therapy for the treatment of acute myeloid leukemia (AML) has the risk of toxicity to normal myeloid cells. CD7 is expressed by the leukemic blasts and malignant progenitor cells of approximately 30% of AML patients but is absent on normal myeloid and erythroid cells. Since CD7 expression by malignant blasts is also linked with chemoresistance and poor outcomes, targeting this antigen may be beneficial for this subset of AML patients. Here, we show that expression of a CD7-directed CAR in CD7 gene-edited (CD7KO) T cells effectively eliminates CD7+ AML cell lines, primary CD7+ AML, and colony-forming cells but spares myeloid and erythroid progenitor cells and their progeny. In a xenograft model, CD7 CAR T cells protect mice against systemic leukemia, prolonging survival. Our results support the feasibility of using CD7KO CD7 CAR T cells for the non-myeloablative treatment of CD7+ AML.


Assuntos
Imunoterapia Adotiva/métodos , Leucemia Mieloide Aguda/terapia , Animais , Antígenos CD7/metabolismo , Humanos , Leucemia Mieloide Aguda/metabolismo , Camundongos , Células Mieloides/metabolismo , Linfócitos T/metabolismo
4.
J Cell Physiol ; 234(2): 1179-1189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30067877

RESUMO

The CD7 antigen is a member of the immunoglobulin superfamily that expresses on the surface of all thymocytes, a majority of mature T cells, and also natural killer cells. Interestingly, under physiological and different pathological conditions, the loss of CD7 antigen occurred in the subset of CD4+ memory T cells. Various functions have been proposed for CD7, including its role in the activation and intercellular adhesiveness of T cells. Several studies indicate that the number of CD4+ CD7- T cells increases in diseases such as chronic inflammation and T-cell malignancies, these being skin inflammatory lesions. Therefore, this can be useful for the diagnosis of cancer cells, especially with reference to blood origin, treatment monitoring, and establishment of new therapies. Therefore, a comprehensive review could be useful to increase our knowledge about the clinical importance of these cells in human disease.


Assuntos
Antígenos CD7/imunologia , Linfócitos T CD4-Positivos/imunologia , Inflamação/imunologia , Ativação Linfocitária , Neoplasias/imunologia , Animais , Antígenos CD7/genética , Antígenos CD7/metabolismo , Apoptose , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Fenótipo , Transdução de Sinais , Evasão Tumoral
7.
Eur J Haematol ; 101(3): 318-325, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29797671

RESUMO

OBJECTIVE: To improve monitoring of myeloid neoplasms by flow cytometry-based minimal residual disease (MRD) analysis, we analyzed the significance of leukemia-associated immunophenotype (LAIP) markers in 44 patients. METHODS: In a pilot study cohort, peripheral blood or bone marrow samples from 13 patients with myeloid neoplasms and one case of B lymphoblastic leukemia in complete hematologic remission after allogeneic bone marrow or stem cell transplantation were subjected to selection for leukemia-specific phenotypes by fluorescence-activated cell sorting using individual marker combinations, followed by PCR-based chimerism analysis. RESULTS: The feasibility of this method could be demonstrated, with selection being successful in 12 cases, including two cases where mixed chimerism was found exclusively in sorted cells. Interestingly, four specimens displayed full donor chimerism in cells expressing the presumably aberrant combination CD34+ /CD7+ . Further analyses, including assessment of an independent cohort of 25 patients not affected by neoplastic bone marrow infiltration, revealed that normal myeloid precursors usually include a population coexpressing CD34, CD13, CD33, and CD7. CONCLUSION: We conclude that the combination CD34+ /CD7+ might not be suitable as an LAIP for MRD diagnostics and that a subset of normal myeloid precursors in the bone marrow expresses CD7.


Assuntos
Antígenos CD34/metabolismo , Antígenos CD7/metabolismo , Células Progenitoras Mieloides/metabolismo , Antígenos CD7/genética , Biomarcadores , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Expressão Gênica , Humanos , Imunofenotipagem , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Células Progenitoras Mieloides/patologia , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Neoplasia Residual/metabolismo
9.
Leukemia ; 32(9): 1970-1983, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29483708

RESUMO

T cell malignancies represent a group of hematologic cancers with high rates of relapse and mortality in patients for whom no effective targeted therapies exist. The shared expression of target antigens between chimeric antigen receptor (CAR) T cells and malignant T cells has limited the development of CAR-T because of unintended CAR-T fratricide and an inability to harvest sufficient autologous T cells. Here, we describe a fratricide-resistant "off-the-shelf" CAR-T (or UCART7) that targets CD7+ T cell malignancies and, through CRISPR/Cas9 gene editing, lacks both CD7 and T cell receptor alpha chain (TRAC) expression. UCART7 demonstrates efficacy against human T cell acute lymphoblastic leukemia (T-ALL) cell lines and primary T-ALL in vitro and in vivo without the induction of xenogeneic GvHD. Fratricide-resistant, allo-tolerant "off-the-shelf" CAR-T represents a strategy for treatment of relapsed and refractory T-ALL and non-Hodgkin's T cell lymphoma without a requirement for autologous T cells.


Assuntos
Imunoterapia Adotiva , Leucemia de Células T/imunologia , Leucemia de Células T/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Animais , Antígenos CD7/genética , Antígenos CD7/imunologia , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Sistemas CRISPR-Cas , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Deleção de Genes , Edição de Genes , Ordem dos Genes , Vetores Genéticos/genética , Humanos , Imunoterapia Adotiva/métodos , Leucemia de Células T/genética , Leucemia de Células T/terapia , Masculino , Camundongos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos Quiméricos/genética , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Cell Death Dis ; 9(3): 293, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29463785

RESUMO

Regulatory T cells in rejected allograft patients display an inability to control responder T cells. Galectin-1 (Gal1) inhibits responder T cells through binding CD7. We investigated whether the dysfunctional immunoregulation in liver allograft rejection patients results from reduced regulatory T-cell Gal1 expression and/or responder T-cell CD7 expression. Circulating regulatory T cells and responder T cells were profiled from 31 acute rejection transplant patients, 85 transplant patients in remission, and 40 healthy controls. CD7+ and CD7- responder T cells were co-cultured with regulatory T cells to assess regulatory T-cell suppressor function. Gal1-small interfering RNA was used to silence regulatory T-cell Gal1. The CD7+ cell percentage was inversely correlated with AST, ALT, and GGT levels. The proportions of CD7+ responder T cells and Gal1+ regulatory T cells were higher in healthy controls than in transplant patients in remission and lowest in acute rejection transplant patients. Notably, CD7+ responder T-cell susceptibility to Gal1+ regulatory T-cell control was ranked in the same manner. Silencing Gal1 expression in regulatory T cells reduced their ability to suppress CD7+ (but not CD7-) responder T cells. Additionally, the proportions of CD43+ and CD45+ responder T cells were higher in healthy controls than in acute rejection transplant patients. CD43 co-expression (but not CD45 co-expression) on CD7+ responder T cells promoted their apoptosis in a Gal1-dependent manner. In sum, dysfunctional immunoregulation in liver allograft rejection patients can be partly attributed to reduced regulatory T-cell Gal1 expression and reduced responder T-cell CD7 expression. Responder T-cell CD43 downregulation in acute rejection patients may further contribute to reduced responder T-cell responsiveness to regulatory T-cell control.


Assuntos
Aloenxertos/imunologia , Antígenos CD7/imunologia , Galectina 1/imunologia , Rejeição de Enxerto/imunologia , Fígado/cirurgia , Adulto , Idoso , Antígenos CD7/genética , Apoptose , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/fisiopatologia , Carcinoma Hepatocelular/cirurgia , Feminino , Galectina 1/genética , Rejeição de Enxerto/genética , Humanos , Leucossialina/genética , Leucossialina/imunologia , Fígado/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/fisiopatologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Adulto Jovem
11.
Theranostics ; 8(21): 6070-6087, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30613283

RESUMO

Cancer immunotherapy has proven high efficacy in treating diverse cancer entities by immune checkpoint modulation and adoptive T-cell transfer. However, patterns of treatment response differ substantially from conventional therapies, and reliable surrogate markers are missing for early detection of responders versus non-responders. Current imaging techniques using 18F-fluorodeoxyglucose-positron-emmission-tomograpy (18F-FDG-PET) cannot discriminate, at early treatment times, between tumor progression and inflammation. Therefore, direct imaging of T cells at the tumor site represents a highly attractive tool to evaluate effective tumor rejection or evasion. Moreover, such markers may be suitable for theranostic imaging. Methods: We mainly investigated the potential of two novel pan T-cell markers, CD2 and CD7, for T-cell tracking by immuno-PET imaging. Respective antibody- and F(ab´)2 fragment-based tracers were produced and characterized, focusing on functional in vitro and in vivo T-cell analyses to exclude any impact of T-cell targeting on cell survival and antitumor efficacy. Results: T cells incubated with anti-CD2 and anti-CD7 F(ab´)2 showed no major modulation of functionality in vitro, and PET imaging provided a distinct and strong signal at the tumor site using the respective zirconium-89-labeled radiotracers. However, while T-cell tracking by anti-CD7 F(ab´)2 had no long-term impact on T-cell functionality in vivo, anti-CD2 F(ab´)2 caused severe T-cell depletion and failure of tumor rejection. Conclusion: This study stresses the importance of extended functional T-cell assays for T-cell tracer development in cancer immunotherapy imaging and proposes CD7 as a highly suitable target for T-cell immuno-PET imaging.


Assuntos
Transferência Adotiva/métodos , Antígenos CD7/análise , Imunoterapia/métodos , Imagem Molecular/métodos , Neoplasias/terapia , Linfócitos T/química , Linfócitos T/imunologia , Animais , Antígenos CD2/análise , Linhagem Celular Tumoral , Modelos Animais de Doenças , Xenoenxertos , Humanos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Camundongos , Transplante de Neoplasias , Tomografia por Emissão de Pósitrons/métodos , Traçadores Radioativos , Compostos Radiofarmacêuticos/administração & dosagem
12.
J Clin Pathol ; 71(2): 174-179, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28916595

RESUMO

AIMS: To create clinically relevant normative flow cytometry data for understudied benign lymph nodes and characterise outliers. METHODS: Clinical, histological and flow cytometry data were collected and distributions summarised for 380 benign lymph node excisional biopsies. Outliers for kappa:lambda light chain ratio, CD10:CD19 coexpression, CD5:CD19 coexpression, CD4:CD8 ratios and CD7 loss were summarised for histological pattern, concomitant diseases and follow-up course. RESULTS: We generated the largest data set of benign lymph node immunophenotypes by an order of magnitude. B and T cell antigen outliers often had background immunosuppression or inflammatory disease but did not subsequently develop lymphoma. CONCLUSIONS: Diagnostic immunophenotyping data from benign lymph nodes provide normative ranges for clinical use. Outliers raising suspicion for B or T cell lymphoma are not infrequent (26% of benign lymph nodes). Caution is indicated when interpreting outliers in the absence of excisional biopsy or clinical history, particularly in patients with concomitant immunosuppression or inflammatory disease.


Assuntos
Linfócitos B/metabolismo , Citometria de Fluxo , Imunofenotipagem , Linfonodos/patologia , Linfócitos T/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD19/metabolismo , Antígenos CD7/metabolismo , Biomarcadores/metabolismo , Biópsia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD5/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Linfonodos/imunologia , Masculino , Pessoa de Meia-Idade , Neprilisina/metabolismo , Valores de Referência , Adulto Jovem
13.
Int J Mol Sci ; 18(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244714

RESUMO

Understanding the pathways and regulation of human haematopoiesis, in particular, lymphopoiesis, is vital to manipulation of these processes for therapeutic purposes. However, although haematopoiesis has been extensively characterised in mice, translation of these findings to human biology remains rudimentary. Here, we describe the isolation of three progenitor subsets from human foetal bone marrow that represent differential stages of commitment to the natural killer (NK) cell lineage based on IL-15 responsiveness. We identify CD7 as a marker of IL-15 responsive progenitors in human bone marrow and find that this expression is maintained throughout commitment and maturation. Within the CD7⁺ fraction, we focussed on the lineage potential of three subsets based on CD127 and CD117 expression and observed restricted lymphoid and biased NK cell potential amongst subsets. We further demonstrate the presence of subsets similar in both phenotype and function in umbilical cord blood and the bone marrow of humanised mice, validating these as appropriate sources of progenitors for the investigation of human haematopoiesis. Overall, we describe several stages in the process of lymphopoiesis that will form the basis of investigating the regulators of this process in humans.


Assuntos
Células da Medula Óssea/citologia , Interleucina-15/metabolismo , Células Matadoras Naturais/citologia , Linfopoese/genética , Animais , Antígenos CD7/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Feto/citologia , Regulação da Expressão Gênica , Humanos , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-kit/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
14.
J Virol ; 91(19)2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724766

RESUMO

We previously reported that the T-cell receptor (TCR) repertoire of human T-cell lymphotropic virus type 1 (HTLV-1) Tax301-309-specific CD8+ cytotoxic T cells (Tax301-309-CTLs) was highly restricted and a particular amino acid sequence motif, the PDR motif, was conserved among HLA-A*24:02-positive (HLA-A*24:02+) adult T-cell leukemia/lymphoma (ATL) patients who had undergone allogeneic hematopoietic cell transplantation (allo-HSCT). Furthermore, we found that donor-derived PDR+ CTLs selectively expanded in ATL long-term HSCT survivors with strong CTL activity against HTLV-1. On the other hand, the TCR repertoires in Tax301-309-CTLs of asymptomatic HTLV-1 carriers (ACs) remain unclear. In this study, we directly identified the DNA sequence of complementarity-determining region 3 (CDR3) of the TCR-ß chain of Tax301-309-CTLs at the single-cell level and compared not only the TCR repertoires but also the frequencies and phenotypes of Tax301-309-CTLs between ACs and ATL patients. We did not observe any essential difference in the frequencies of Tax301-309-CTLs between ACs and ATL patients. In the single-cell TCR repertoire analysis of Tax301-309-CTLs, 1,458 Tax301-309-CTLs and 140 clones were identified in this cohort. Tax301-309-CTLs showed highly restricted TCR repertoires with a strongly biased usage of BV7, and PDR, the unique motif in TCR-ß CDR3, was exclusively observed in all ACs and ATL patients. However, there was no correlation between PDR+ CTL frequencies and HTLV-1 proviral load (PVL). In conclusion, we have identified, for the first time, a unique amino acid sequence, PDR, as a public TCR-CDR3 motif against Tax in HLA-A*24:02+ HTLV-1-infected individuals. Further investigations are warranted to elucidate the role of the PDR+ CTL response in the progression from carrier state to ATL.IMPORTANCE ATL is an aggressive T-cell malignancy caused by HTLV-1 infection. The HTLV-1 regulatory protein Tax aggressively promotes the proliferation of HTLV-1-infected lymphocytes and is also a major target antigen for CD8+ CTLs. In our previous evaluation of Tax301-309-CTLs, we found that a unique amino acid sequence motif, PDR, in CDR3 of the TCR-ß chain of Tax301-309-CTLs was conserved among ATL patients after allo-HSCT. Furthermore, the PDR+ Tax301-309-CTL clones selectively expanded and showed strong cytotoxic activities against HTLV-1. On the other hand, it remains unclear how Tax301-309-CTL repertoire exists in ACs. In this study, we comprehensively compared Tax-specific TCR repertoires at the single-cell level between ACs and ATL patients. Tax301-309-CTLs showed highly restricted TCR repertoires with a strongly biased usage of BV7, and PDR, the unique motif in TCR-ß CDR3, was conserved in all ACs and ATL patients, regardless of clinical subtype in HTLV-1 infection.


Assuntos
Produtos do Gene tax/imunologia , Antígeno HLA-A24/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Leucemia-Linfoma de Células T do Adulto/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos/genética , Antígenos CD7/metabolismo , Molécula 1 de Adesão Celular , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Produtos do Gene tax/genética , Antígeno HLA-A24/genética , Infecções por HTLV-I/patologia , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Imunoglobulinas/metabolismo , Memória Imunológica/imunologia , Leucemia-Linfoma de Células T do Adulto/genética , Receptores de Antígenos de Linfócitos T/genética
15.
Blood ; 130(3): 285-296, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28539325

RESUMO

Extending the success of chimeric antigen receptor (CAR) T cells to T-cell malignancies is problematic because most target antigens are shared between normal and malignant cells, leading to CAR T-cell fratricide. CD7 is a transmembrane protein highly expressed in acute T-cell leukemia (T-ALL) and in a subset of peripheral T-cell lymphomas. Normal expression of CD7 is largely confined to T cells and natural killer (NK) cells, reducing the risk of off-target-organ toxicity. Here, we show that the expression of a CD7-specific CAR impaired expansion of transduced T cells because of residual CD7 expression and the ensuing fratricide. We demonstrate that targeted genomic disruption of the CD7 gene prevented this fratricide and enabled expansion of CD7 CAR T cells without compromising their cytotoxic function. CD7 CAR T cells produced robust cytotoxicity against malignant T-cell lines and primary tumors and were protective in a mouse xenograft model of T-ALL. Although CD7 CAR T cells were also toxic against unedited (CD7+) T and NK lymphocytes, we show that the CD7-edited T cells themselves can respond to viral peptides and therefore could be protective against pathogens. Hence, genomic disruption of a target antigen overcomes fratricide of CAR T cells and establishes the feasibility of using CD7 CAR T cells for the targeted therapy of T-cell malignancies.


Assuntos
Antígenos CD7/imunologia , Citotoxicidade Imunológica , Imunoterapia Adotiva/métodos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/transplante , Animais , Antígenos CD7/genética , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Masculino , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes de Fusão/genética , Linfócitos T/citologia , Linfócitos T/imunologia , Transdução Genética , Transplante Heterólogo
16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(6): 1627-1632, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-28024467

RESUMO

OBJECTIVE: To explore the features of immunophenotypes and the characteristics of molecular biology and cellular genetics of AML patients with CD7 and CD4 expression. METHODS: The immunophenotypical markers of AML cells were detected by multiple parameter flow cytometry; the expression of WT1, MDK, ETO, PML-RaRa and BCR-ABL were detected by RT-PCR; and cellular features were analyzed by R-band in 304 patients. The patients were divided into three groups according to their immunophenotypes: AML with CD7 expression (CD7 group), AML with CD4 expression(CD4 group) and AML without CD7 and CD4 expression (common AML group). RESULTS: The expression rate and level of HLA-DR in CD7 group were higher than those in the common AML group, and the expression rate of CD33 and CD34 was higher than that in the other two groups. The expression rate and level of CD15, CD64 in the CD4 group were higher than those in the other 2 groups, and the expression rate and level of CD33 were higher than those in the common AML group. WT1 expression in the CD7 group was lower than that in the common AML group. PML-RaRa was not detected in the CD7 group. AML with co-expression of CD4 or CD7 showed more normal karyotype. (15;17) was not found in AML with CD7 expression. CONCLUSION: AML cells with CD7 expression originate from precursor cells and are blocked in the early phase of hematological development; AML cells with CD4 expression originate from more mature stage of hematological devevelopment and with CD33, CD64 and CD15 high expression; AML cells with CD7 and CD4 expression are characterized by no-specific change of cellular genetics. According to the expression level and intesity of CD4 and CD7, and together with other specific lineage markers, the MRD in AML patients can be quantitatively detected.


Assuntos
Imunofenotipagem , Leucemia Mieloide Aguda , Antígenos CD7 , Antígenos CD4 , Contagem de Células , Bandeamento Cromossômico , Citometria de Fluxo , Proteínas de Fusão bcr-abl , Antígenos HLA-DR , Humanos , Biologia Molecular , Receptores de IgG , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
18.
Oncotarget ; 7(44): 71915-71921, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713120

RESUMO

We investigated the ability of support vector machines (SVM) to analyze minimal residual disease (MRD) in flow cytometry data from patients with acute myeloid leukemia (AML) automatically, objectively and standardly. The initial disease data and MRD review data in the form of 159 flow cytometry standard 3.0 files from 36 CD7-positive AML patients in whom MRD was detected more than once were exported. SVM was used for training with setting the initial disease data to 1 as the flag and setting 15 healthy persons to set 0 as the flag. Based on the two training groups, parameters were optimized, and a predictive model was built to analyze MRD data from each patient. The automated analysis results from the SVM model were compared to those obtained through conventional analysis to determine reliability. Automated analysis results based on the model did not differ from and were correlated with results obtained through conventional analysis (correlation coefficient c = 0.986, P > 0.05). Thus the SVM model could potentially be used to analyze flow cytometry-based AML MRD data automatically, objectively, and in a standardized manner.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Máquina de Vetores de Suporte , Adolescente , Adulto , Idoso , Antígenos CD7/análise , Feminino , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Adulto Jovem
19.
Pediatr Blood Cancer ; 63(10): 1848-51, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27348401

RESUMO

Composition of tumour immune cell infiltrates correlates with response to treatment and overall survival (OS) in several cancer settings. We retrospectively examined immune cells present in diagnostic bone marrow aspirates from paediatric patients with B-cell acute lymphoblastic leukaemia. Our analysis identified a sub-group (∼30% of patients) with >2.37% CD20 and >6.05% CD7 expression, which had 100% OS, and a sub-group (∼30% of patients) with ≤2.37% CD20 and ≤6.05% CD7 expression at increased risk of treatment failure (66.7% OS, P < 0.05). Immune cell infiltrate at diagnosis may predict treatment response and could provide a means to enhance immediate treatment risk stratification.


Assuntos
Medula Óssea/patologia , Linfócitos/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Antígenos CD20/análise , Antígenos CD7/análise , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Estudos Retrospectivos
20.
Oncotarget ; 7(23): 34070-83, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27083001

RESUMO

Various CD7-targeting immunotoxins have been tested for its potential in treating CD7+ malignant patients but none of those immunotoxins was approved clinically because of lacking enough efficacy and safety. Here we successfully constructed the monovalent and bivalent CD7 nanobody-based immunotoxins PG001 and PG002, both conjugated with a truncated derivative of Pseudomonas exotoxin A respectively. The prokaryotic system expressed immunotoxins not only maintained their binding specificity for CD7-positive cells with a Kd of 16.74 nM and 3.6 nM for PG001 and PG002 respectively, but also efficiently promoted antigen-restricted apoptosis of the CD7-positive leukemia cell lines Jurkat and CEM, and primary T-cell acute lymphoblastic leukemia (T-ALL) and acute myeloid leukemia (AML) cells with an in vitro cytotoxic activity (EC50) in the range of 23-30 pM for PG002. In NOD/SCID mice transplanted with CEM cells, PG001 and PG002 prevented engraftment of the cells and markedly prolonged mouse survival. Owing to the efficient antigen-restricted anti-leukemic activity of PG002, this CD7 nanobody-based immunotoxin exhibited a superior anti-CD7 positive malignancies activity than previously reported immunotoxins, and may represent a promising therapeutic strategy in treating CD7-positive leukemia and lymphoma, which still remain a significant clinical challenge.


Assuntos
Antineoplásicos/farmacologia , Imunotoxinas/farmacologia , Anticorpos de Domínio Único/farmacologia , Animais , Antígenos CD7 , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Leucemia-Linfoma de Células T do Adulto , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA