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1.
J Exp Med ; 204(10): 2335-48, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17875673

RESUMO

It is well established that intraepithelial T lymphocytes (IELs) are derived from conventional single-positive (SP) thymocytes, as well as unconventional double-negative (DN) thymocytes and CD103+CD8alphabeta recent thymic emigrants (RTEs). We show that IELs can be divided into two groups according to their dependency on sphingosine 1-phosphate (S1P) for trafficking into the intestines. CD4 or CD8alphabeta naive lymphocytes originating from SP thymocytes express high levels of type 1 S1P receptor (S1P(1)), and their preferential migration into the large intestine is regulated by S1P. In contrast, RTEs migrate exclusively into the small intestine, whereas DN thymic IEL precursors expressing either TCRalphabeta or TCRgammadelta migrate into both the small and large intestines. S1P does not play a role in the migration pathways of these unconventional thymic IEL precursors. Thus, down-regulation of S1P(1) expression or disruption of the S1P gradient halted conventional CD4 or CD8alphabeta IEL trafficking into the intestines, but did not affect the trafficking of unconventional thymic IEL precursors. These data are the first to demonstrate that a lipid-mediated system discriminates IELs originating from conventional and unconventional thymic precursors.


Assuntos
Movimento Celular/imunologia , Intestinos/citologia , Intestinos/imunologia , Linfócitos/citologia , Linfócitos/imunologia , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Animais , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular/imunologia , Movimento Celular/efeitos dos fármacos , Epitélio/imunologia , Feminino , Cloridrato de Fingolimode , Ativação Linfocitária/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Propilenoglicóis/farmacologia , Sensibilidade e Especificidade , Esfingosina/metabolismo , Esfingosina/farmacologia , Timo/citologia , Timo/imunologia
2.
J Immunol ; 186(9): 5254-60, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21421855

RESUMO

Basophils are the rarest leukocytes in human blood, but they are now recognized as one of the most important immunomodulatory as well as effector cells in allergic inflammation. Leptin, a member of the IL-6 cytokine family, has metabolic effects as an adipokine, and it is also known to participate in the pathogenesis of inflammatory reactions. Because there is an epidemiologic relationship between obesity and allergy, we examined whether basophil functions are modified by leptin. We found that human basophils express leptin receptor (LepR) at both the mRNA and surface protein levels, which were upregulated by IL-33. Leptin exerted strong effects on multiple basophil functions. It induced a strong migratory response in human basophils, similar in potency to that of basophil-active chemokines. Also, leptin enhanced survival of human basophils, although its potency was less than that of IL-3. Additionally, CD63, a basophil activation marker expressed on the cell surface, was upregulated by leptin, an effect that was neutralized by blocking of LepR. Assessments of basophil degranulation and cytokine synthesis found that leptin showed a strong priming effect on human basophil degranulation in response to FcεRI aggregation and induced Th2, but not Th1, cytokine production by the cells. In summary, the present findings indicate that leptin may be a key molecule mediating the effects of adipocytes on inflammatory cells such as basophils by binding to LepR and activating the cellular functions, presumably exacerbating allergic inflammation.


Assuntos
Basófilos/imunologia , Degranulação Celular/imunologia , Movimento Celular/imunologia , Citocinas/biossíntese , Leptina/imunologia , Antígenos CD/biossíntese , Basófilos/citologia , Basófilos/metabolismo , Separação Celular , Sobrevivência Celular/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Leptina/metabolismo , Glicoproteínas da Membrana de Plaquetas/biossíntese , Receptores para Leptina/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tetraspanina 30
3.
EBioMedicine ; 64: 103235, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33581643

RESUMO

BACKGROUND: Acute lymphoblastic leukaemia with mixed lineage leukaemia gene rearrangement (MLL-ALL) frequently affects infants and is associated with a poor prognosis. Primary refractory and relapsed disease due to resistance to glucocorticoids (GCs) remains a substantial hurdle to improving clinical outcomes. In this study, we aimed to overcome GC resistance of MLL-ALL. METHODS: Using leukaemia patient specimens, we performed bioinformatic analyses to identify target genes/pathways. To test inhibition of target pathways in vivo, we created pre-clinical therapeutic mouse patient-derived xenograft (PDX)-models by transplanting human MLL-ALL leukaemia initiating cells (LIC) into immune-deficient NSG mice. Finally, we conducted B-cell lymphoma-2 (BCL-2) homology domain 3 (BH3) profiling to identify BH3 peptides responsible for treatment resistance in MLL-leukaemia. FINDINGS: Src family kinases (SFKs) and Fms-like tyrosine kinase 3 (FLT3) signaling pathway were over-represented in MLL-ALL cells. PDX-models of infant MLL- ALL recapitulated GC-resistance in vivo but RK-20449, an inhibitor of SFKs and FLT3 eliminated human MLL-ALL cells in vivo, overcoming GC-resistance. Further, we identified BCL-2 dependence as a mechanism of treatment resistance in MLL-ALL through BH3 profiling. Furthermore, MLL-ALL cells resistant to RK-20449 treatment were dependent on the anti-apoptotic BCL-2 protein for their survival. Combined inhibition of SFKs/FLT3 by RK-20449 and of BCL-2 by ABT-199 led to substantial elimination of MLL-ALL cells in vitro and in vivo. Triple treatment combining GCs, RK-20449 and ABT-199 resulted in complete elimination of MLL-ALL cells in vivo. INTERPRETATION: SFKs/FLT3 signaling pathways are promising targets for treatment of treatment-resistant MLL-ALL. Combined inhibition of these kinase pathways and anti-apoptotic BCL-2 successfully eliminated highly resistant MLL-ALL and demonstrated a new treatment strategy for treatment-resistant poor-outcome MLL-ALL. FUNDING: This study was supported by RIKEN (RIKEN President's Discretionary Grant) for FI, Japan Agency for Medical Research and Development (the Basic Science and Platform Technology Program for Innovative Biological Medicine for FI and by NIH CA034196 for LDS. The funders had no role in the study design, data collection, data analysis, interpretation nor writing of the report.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/genética , Resistencia a Medicamentos Antineoplásicos/genética , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sinergismo Farmacológico , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Pirimidinas/farmacologia , Pirróis/farmacologia , Esteroides/farmacologia , Esteroides/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Nat Cancer ; 2(3): 340-356, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-35121960

RESUMO

Aggressive therapy-resistant and refractory acute myeloid leukemia (AML) has an extremely poor outcome. By analyzing a large number of genetically complex and diverse, primary high-risk poor-outcome human AML samples, we identified specific pathways of therapeutic vulnerability. Through drug screens followed by extensive in vivo validation and genomic analyses, we found inhibition of cytosolic and mitochondrial anti-apoptotic proteins XIAP, BCL2 and MCL1, and a key regulator of mitosis, AURKB, as a vulnerability hub based on patient-specific genetic aberrations and transcriptional signatures. Combinatorial therapeutic inhibition of XIAP with an additional patient-specific vulnerability eliminated established AML in vivo in patient-derived xenografts (PDXs) bearing diverse genetic aberrations, with no signs of recurrence during off-treatment follow-up. By integrating genomic profiling and drug-sensitivity testing, this work provides a platform for a precision-medicine approach for treating aggressive AML with high unmet need.


Assuntos
Leucemia Mieloide Aguda , Proteínas Proto-Oncogênicas c-bcl-2 , Apoptose/genética , Proteínas Reguladoras de Apoptose/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética
5.
Sci Transl Med ; 9(413)2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070697

RESUMO

Numerous variant alleles are associated with human acute myeloid leukemia (AML). However, the same variants are also found in individuals with no hematological disease, making their functional relevance obscure. Through NOD.Cg-PrkdcscidIl2rgtmlWjl/Sz (NSG) xenotransplantation, we functionally identified preleukemic and leukemic stem cell populations present in FMS-like tyrosine kinase 3 internal tandem duplication-positive (FLT3-ITD)+ AML patient samples. By single-cell DNA sequencing, we identified clonal structures and linked mutations with in vivo fates, distinguishing mutations permissive of nonmalignant multilineage hematopoiesis from leukemogenic mutations. Although multiple somatic mutations coexisted at the single-cell level, inhibition of the mutation strongly associated with preleukemic to leukemic stem cell transition eliminated AML in vivo. Moreover, concurrent inhibition of BCL-2 (B cell lymphoma 2) uncovered a critical dependence of resistant AML cells on antiapoptotic pathways. Co-inhibition of pathways critical for oncogenesis and survival may be an effective strategy that overcomes genetic diversity in human malignancies. This approach incorporating single-cell genomics with the NSG patient-derived xenograft model may serve as a broadly applicable resource for precision target identification and drug discovery.


Assuntos
Leucemia Mieloide Aguda/genética , Mutação/genética , Transdução de Sinais/genética , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Células Clonais , Feminino , Genômica , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Análise de Sequência de DNA , Análise de Célula Única , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Sci Transl Med ; 5(181): 181ra52, 2013 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-23596204

RESUMO

Leukemia stem cells (LSCs) that survive conventional chemotherapy are thought to contribute to disease relapse, leading to poor long-term outcomes for patients with acute myeloid leukemia (AML). We previously identified a Src-family kinase (SFK) member, hematopoietic cell kinase (HCK), as a molecular target that is highly differentially expressed in human primary LSCs compared with human normal hematopoietic stem cells (HSCs). We performed a large-scale chemical library screen that integrated a high-throughput enzyme inhibition assay, in silico binding prediction, and crystal structure determination and found a candidate HCK inhibitor, RK-20449, a pyrrolo-pyrimidine derivative with an enzymatic IC50 (half maximal inhibitory concentration) in the subnanomolar range. A crystal structure revealed that RK-20449 bound the activation pocket of HCK. In vivo administration of RK-20449 to nonobese diabetic (NOD)/severe combined immunodeficient (SCID)/IL2rg(null) mice engrafted with highly aggressive therapy-resistant AML significantly reduced human LSC and non-stem AML burden. By eliminating chemotherapy-resistant LSCs, RK-20449 may help to prevent relapse and lead to improved patient outcomes in AML.


Assuntos
Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Adulto , Idoso , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Cristalografia por Raios X , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Hematopoese/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Camundongos , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-hck/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-hck/química , Proteínas Proto-Oncogênicas c-hck/metabolismo , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , RNA Interferente Pequeno/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células Tumorais Cultivadas , Adulto Jovem
7.
J Immunol ; 180(8): 5335-43, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18390715

RESUMO

It is well established that Peyer's patches (PPs) are sites for the differentiation of IgA plasma cell precursors, but molecular and cellular mechanisms in their trafficking remain to be elucidated. In this study, we show that alterations in type 1 sphingosine 1-phosphate (S1P) receptor expression during B cell differentiation in the PPs control the emigration of IgA plasma cell precursors. Type 1 S1P receptor expression decreased during the differentiation of IgM(+)B220(+) B cells to IgA(+)B220(+) B cells, but recovered on IgA(+)B220(-) plasmablasts for their emigration from the PPs. Thus, IgA(+)B220(-) plasmablasts migrated in response to S1P in vitro. Additionally, IgA(+) plasmablasts selectively accumulated in lymphatic regions of PPs when S1P-mediated signaling was disrupted by FTY720 treatment. This accumulation of IgA(+) plasmablasts in the PPs led to their reduction in the intestinal lamina propria and simultaneous impairment of Ag-specific intestinal IgA production against orally administered Ag. These findings suggest that S1P regulates the retention and emigration of PP B cells and plays key roles in the induction of intestinal IgA production.


Assuntos
Linfócitos B/imunologia , Imunoglobulina A/metabolismo , Mucosa Intestinal/metabolismo , Lisofosfolipídeos/metabolismo , Nódulos Linfáticos Agregados/imunologia , Esfingosina/análogos & derivados , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Feminino , Cloridrato de Fingolimode , Imunoglobulina A/imunologia , Imunossupressores/administração & dosagem , Imunossupressores/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Lisofosfolipídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/efeitos dos fármacos , Plasmócitos/citologia , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Propilenoglicóis/administração & dosagem , Propilenoglicóis/farmacologia , Esfingosina/administração & dosagem , Esfingosina/imunologia , Esfingosina/metabolismo , Esfingosina/farmacologia
8.
Blood ; 109(9): 3749-56, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17234743

RESUMO

Sphingosine 1-phosphate (S1P) is known to play a pivotal role in the regulation of lymphocyte emigration from organized lymphoid tissues such as the peripheral lymph nodes and thymus, but its immunologic role in unorganized and diffused tissues remains to be elucidated. Here we show that the trafficking of peritoneal B cells is principally regulated by S1P. All peritoneal B cells including B1a, B1b, and B2 B cells express comparable levels of the type 1 S1P receptor. Thus, treatment with FTY720, an S1P receptor modulator, caused the rapid disappearance of peritoneal B cells by inhibiting both their emigration from parathymic lymph nodes and their recirculation from the blood into the peritoneal cavity without affecting their progenitor populations. These changes did not affect natural plasma antibody production or phosphorylcholine (PC)-specific antibody production in serum after peritoneal immunization with heat-killed Streptococcal pneumoniae (R36A). However, FTY720 dramatically reduced peritoneal B cell-derived natural intestinal secretory IgA production without affecting the expression of J-chain and polyimmunoglobulin receptors. Additionally, FTY720 impaired the generation of PC-specific fecal IgA responses after oral immunization with R36A. These findings point to a pivotal role for S1P in connecting peritoneal B cells with intestinal B-cell immunity.


Assuntos
Linfócitos B/imunologia , Movimento Celular/efeitos dos fármacos , Imunoglobulina A/imunologia , Imunossupressores/farmacologia , Intestino Delgado/imunologia , Cavidade Peritoneal , Propilenoglicóis/farmacologia , Receptores de Lisoesfingolipídeo/agonistas , Esfingosina/análogos & derivados , Animais , Anticorpos Antifosfolipídeos/biossíntese , Anticorpos Antifosfolipídeos/imunologia , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Linfócitos B/metabolismo , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/farmacologia , Feminino , Cloridrato de Fingolimode , Imunoglobulina A/metabolismo , Cadeias J de Imunoglobulina/biossíntese , Cadeias J de Imunoglobulina/imunologia , Intestino Delgado/metabolismo , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Lisofosfolipídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos SCID , Receptores de Lisoesfingolipídeo/biossíntese , Receptores de Lisoesfingolipídeo/imunologia , Esfingosina/farmacologia , Streptococcus pneumoniae/imunologia , Vacinação
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