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1.
Nat Immunol ; 25(7): 1207-1217, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38802512

RESUMO

The contribution of γδ T cells to immune responses is associated with rapid secretion of interferon-γ (IFN-γ). Here, we show a perinatal thymic wave of innate IFN-γ-producing γδ T cells that express CD8αß heterodimers and expand in preclinical models of infection and cancer. Optimal CD8αß+ γδ T cell development is directed by low T cell receptor signaling and through provision of interleukin (IL)-4 and IL-7. This population is pathologically relevant as overactive, or constitutive, IL-7R-STAT5B signaling promotes a supraphysiological accumulation of CD8αß+ γδ T cells in the thymus and peripheral lymphoid organs in two mouse models of T cell neoplasia. Likewise, CD8αß+ γδ T cells define a distinct subset of human T cell acute lymphoblastic leukemia pediatric patients. This work characterizes the normal and malignant development of CD8αß+ γδ T cells that are enriched in early life and contribute to innate IFN-γ responses to infection and cancer.


Assuntos
Imunidade Inata , Interferon gama , Receptores de Antígenos de Linfócitos T gama-delta , Receptores de Interleucina-7 , Fator de Transcrição STAT5 , Timo , Animais , Interferon gama/metabolismo , Interferon gama/imunologia , Camundongos , Humanos , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Timo/imunologia , Receptores de Interleucina-7/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/imunologia , Camundongos Endogâmicos C57BL , Linfócitos T CD8-Positivos/imunologia , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Antígenos CD8/metabolismo , Feminino , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Interleucina-7/metabolismo
2.
Blood ; 138(12): 1040-1052, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-33970999

RESUMO

Tight regulation of IL-7Rα expression is essential for normal T-cell development. IL-7Rα gain-of-function mutations are known drivers of T-cell acute lymphoblastic leukemia (T-ALL). Although a subset of patients with T-ALL display high IL7R messenger RNA levels and cases with IL7R gains have been reported, the impact of IL-7Rα overexpression, rather than mutational activation, during leukemogenesis remains unclear. In this study, overexpressed IL-7Rα in tetracycline-inducible Il7r transgenic and Rosa26 IL7R knockin mice drove potential thymocyte self-renewal, and thymus hyperplasia related to increased proliferation of T-cell precursors, which subsequently infiltrated lymph nodes, spleen, and bone marrow, ultimately leading to fatal leukemia. The tumors mimicked key features of human T-ALL, including heterogeneity in immunophenotype and genetic subtype between cases, frequent hyperactivation of the PI3K/Akt pathway paralleled by downregulation of p27Kip1 and upregulation of Bcl-2, and gene expression signatures evidencing activation of JAK/STAT, PI3K/Akt/mTOR and Notch signaling. Notably, we also found that established tumors may no longer require high levels of IL-7R expression upon secondary transplantation and progressed in the absence of IL-7, but remain sensitive to inhibitors of IL-7R-mediated signaling ruxolitinib (Jak1), AZD1208 (Pim), dactolisib (PI3K/mTOR), palbociclib (Cdk4/6), and venetoclax (Bcl-2). The relevance of these findings for human disease are highlighted by the fact that samples from patients with T-ALL with high wild-type IL7R expression display a transcriptional signature resembling that of IL-7-stimulated pro-T cells and, critically, of IL7R-mutant cases of T-ALL. Overall, our study demonstrates that high expression of IL-7Rα can promote T-cell tumorigenesis, even in the absence of IL-7Rα mutational activation.


Assuntos
Carcinogênese , Regulação Leucêmica da Expressão Gênica , Mutação , Proteínas de Neoplasias , Neoplasias Experimentais , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Receptores de Interleucina-7 , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Receptores de Interleucina-7/biossíntese , Receptores de Interleucina-7/genética , Transdução de Sinais , Timócitos/metabolismo
3.
Eur J Immunol ; 51(12): 3194-3201, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34564853

RESUMO

Accelerate lung repair in SARS-CoV-2 pneumonia is essential for pandemic handling. Innate lymphoid cells (ILCs) are likely players, given their role in mucosal protection and tissue homeostasis. We studied ILC subpopulations at two time points in a cohort of patients admitted in the hospital due to SARS-CoV-2 infection. COVID-19 patients with moderate/severe respiratory failure featured profound depletion of circulating ILCs at hospital admission, in agreement with overall lymphocyte depletion. However, ILCs recovered in direct correlation with lung function improvement as measured by oxygenation index and in negative association with inflammatory and lung/endothelial damage markers like RAGE. While both ILC1 and ILC2 expanded, ILC2 showed the most striking phenotype changes, with CCR10 upregulation in strong correlation with these parameters. Overall, CCR10+ ILC2 emerge as relevant contributors to SARS-CoV-2 pneumonia recovery.


Assuntos
Biomarcadores/metabolismo , COVID-19/imunologia , Pulmão/patologia , Linfócitos/imunologia , Pneumonia Viral/imunologia , Receptores CCR10/metabolismo , SARS-CoV-2/fisiologia , Adulto , Idoso , Antígenos de Neoplasias/metabolismo , Proliferação de Células , Citocinas/metabolismo , Feminino , Humanos , Imunidade Inata , Masculino , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Recuperação de Função Fisiológica , Células Th2/imunologia , Regulação para Cima
4.
Blood ; 135(19): 1685-1695, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32315407

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) and T-cell acute lymphoblastic lymphoma (T-LBL) are aggressive hematological malignancies that are currently treated with high-dose chemotherapy. Over the last several years, the search toward novel and less-toxic therapeutic strategies for T-ALL/T-LBL patients has largely focused on the identification of cell-intrinsic properties of the tumor cell. However, non-cell-autonomous activation of specific oncogenic pathways might also offer opportunities that could be exploited at the therapeutic level. In line with this, we here show that endogenous interleukin 7 (IL7) can increase the expression of the oncogenic kinase proviral integration site for Moloney-murine leukemia 1 (PIM1) in CD127+ T-ALL/T-LBL, thereby rendering these tumor cells sensitive to in vivo PIM inhibition. In addition, using different CD127+ T-ALL/T-LBL xenograft models, we also reveal that residual tumor cells, which remain present after short-term in vivo chemotherapy, display consistent upregulation of PIM1 as compared with bulk nontreated tumor cells. Notably, this effect was transient as increased PIM1 levels were not observed in reestablished disease after abrogation of the initial chemotherapy. Furthermore, we uncover that this phenomenon is, at least in part, mediated by the ability of glucocorticoids to cause transcriptional upregulation of IL7RA in T-ALL/T-LBL patient-derived xenograft (PDX) cells, ultimately resulting in non-cell-autonomous PIM1 upregulation by endogenous IL7. Finally, we confirm in vivo that chemotherapy in combination with a pan-PIM inhibitor can improve leukemia survival in a PDX model of CD127+ T-ALL. Altogether, our work reveals that IL7 and glucocorticoids coordinately drive aberrant activation of PIM1 and suggests that IL7-responsive CD127+ T-ALL and T-LBL patients could benefit from PIM inhibition during induction chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Citocinas/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Linfócitos T/imunologia , Animais , Apoptose , Proliferação de Células , Quimioterapia Combinada , Humanos , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Linfócitos T/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nature ; 514(7520): 98-101, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25079320

RESUMO

Haematopoiesis is a developmental cascade that generates all blood cell lineages in health and disease. This process relies on quiescent haematopoietic stem cells capable of differentiating, self renewing and expanding upon physiological demand. However, the mechanisms that regulate haematopoietic stem cell homeostasis and function remain largely unknown. Here we show that the neurotrophic factor receptor RET (rearranged during transfection) drives haematopoietic stem cell survival, expansion and function. We find that haematopoietic stem cells express RET and that its neurotrophic factor partners are produced in the haematopoietic stem cell environment. Ablation of Ret leads to impaired survival and reduced numbers of haematopoietic stem cells with normal differentiation potential, but loss of cell-autonomous stress response and reconstitution potential. Strikingly, RET signals provide haematopoietic stem cells with critical Bcl2 and Bcl2l1 surviving cues, downstream of p38 mitogen-activated protein (MAP) kinase and cyclic-AMP-response element binding protein (CREB) activation. Accordingly, enforced expression of RET downstream targets, Bcl2 or Bcl2l1, is sufficient to restore the activity of Ret null progenitors in vivo. Activation of RET results in improved haematopoietic stem cell survival, expansion and in vivo transplantation efficiency. Remarkably, human cord-blood progenitor expansion and transplantation is also improved by neurotrophic factors, opening the way for exploration of RET agonists in human haematopoietic stem cell transplantation. Our work shows that neurotrophic factors are novel components of the haematopoietic stem cell microenvironment, revealing that haematopoietic stem cells and neurons are regulated by similar signals.


Assuntos
Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Fatores de Crescimento Neural/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Animais , Sobrevivência Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Enzimática , Feminino , Hematopoese , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-ret/deficiência , Proteínas Proto-Oncogênicas c-ret/genética , Transdução de Sinais , Nicho de Células-Tronco , Proteína bcl-X/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Eur J Immunol ; 44(12): 3605-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25168352

RESUMO

T helper (Th) cells are critical players in the modulation of immune response outcomes. Activation of Th cells gives rise to various subsets of effector cells that are controlled via specialised regulatory T cells or through self-regulation via production of IL-10. However, the environmental factors that regulate IL-10 production by Th cells remain poorly understood. Here, we show that the neurotrophic factor receptor rearranged during transfection (RET) downregulates IL-10 production by Th cells from C57BL/6 mice. We found that effector Th cells express RET and that RET's neurotrophic factor partners are mainly produced by LN stromal cells, allowing context-dependent Th-cell regulation. Despite being dispensable for Th-cell homeostasis, RET controls IL-10 production in Th2 cells: RET-deficient Th cells exhibited increased IL-10 production, while triggering of Th1/2 cells with neurotrophic factors, namely glial-derived neurotrophic factor and neurturin, decreased the expression of IL-10. In agreement, the important IL-10 transcription factor Maf was upregulated in RET-deficient Th2 cells and down-regulated upon RET signalling activation by glial-derived neurotrophic factor family ligands. Thus, our study uncovers neurotrophic factors as novel regulators of Th-cell function, revealing that Th cells and neurons can be regulated by similar signals in tissue-specific responses.


Assuntos
Interleucina-10/imunologia , Neurturina/imunologia , Proteínas Proto-Oncogênicas c-ret/imunologia , Transdução de Sinais/imunologia , Células Th2/imunologia , Animais , Interleucina-10/genética , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Knockout , Neuroglia/citologia , Neuroglia/imunologia , Neurônios/citologia , Neurônios/imunologia , Neurturina/genética , Proteínas Proto-Oncogênicas c-ret/genética , Transdução de Sinais/genética , Células Estromais/citologia , Células Estromais/imunologia , Células Th1/citologia , Células Th1/imunologia , Células Th2/citologia
7.
Cell Mol Immunol ; 20(8): 955-968, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37344746

RESUMO

T-cell development ensures the formation of diverse repertoires of T-cell receptors (TCRs) that recognize a variety of antigens. Glycosylation is a major posttranslational modification present in virtually all cells, including T-lymphocytes, that regulates activity/functions. Although these structures are known to be involved in TCR-selection in DP thymocytes, it is unclear how glycans regulate other thymic development processes and how they influence susceptibility to disease. Here, we discovered stage-specific glycome compositions during T-cell development in human and murine thymocytes, as well as dynamic alterations. After restricting the N-glycosylation profile of thymocytes to high-mannose structures, using specific glycoengineered mice (Rag1CreMgat1fl/fl), we showed remarkable defects in key developmental checkpoints, including ß-selection, regulatory T-cell generation and γδT-cell development, associated with increased susceptibility to colon and kidney inflammation and infection. We further demonstrated that a single N-glycan antenna (modeled in Rag1CreMgat2fl/fl mice) is the sine-qua-non condition to ensure normal development. In conclusion, we revealed that mannosylated thymocytes lead to a dysregulation in T-cell development that is associated with inflammation susceptibility.


Assuntos
Timócitos , Timo , Camundongos , Animais , Humanos , Glicosilação , Receptores de Antígenos de Linfócitos T/metabolismo , Proteínas de Homeodomínio/genética , Polissacarídeos
8.
Eur J Immunol ; 40(12): 3478-88, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21108468

RESUMO

Peripheral T-cell expansion is of major relevance for immune function after lymphopenia. In order to promote regeneration, the process should result in a peripheral T-cell pool with a similar subpopulation structure as before lymphopenia. We investigated the repopulation of the CD8(+) central-memory T cells (T(CM) ) and effector-memory T cells (T(EM)) pools after adoptive transfer of sorted CD8(+) T cells from naïve, T(CM) and T(EM) subsets into T-cell-deficient hosts. We show that the initial kinetics of expansion are distinct for each subset and that the contribution to the repopulation of the CD8(+) T-cell pool by the progeny of each subset is not a mere function of its initial expansion. We demonstrate that CD4(+) CD25(+) Treg play a major role in the repopulation of the CD8(+) T-cell pool and that CD8(+) T-cell subsets impact on each other. In the absence of CD4(+) CD25(+) Treg, a small fraction of naïve CD8(+) T cells strongly proliferates, correlating with further expansion and differentiation of co-expanding CD8(+) T cells. CD4(+) CD25(+) Treg suppress these responses and lead to controlled repopulation, contributing decisively to the maintenance of recovered T(CM) and T(EM) fractions, and leading to repopulation of each pool with progeny of its own kind.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Linfopenia/imunologia , Linfócitos T Reguladores/metabolismo , Transferência Adotiva , Animais , Complexo CD3/genética , Antígenos CD4/biossíntese , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Comunicação Celular , Sobrevivência Celular/imunologia , Memória Imunológica , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Linfopenia/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regeneração , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
9.
Front Immunol ; 12: 691725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248984

RESUMO

After more than one year since the COVID-19 outbreak, patients with severe disease still constitute the bottleneck of the pandemic management. Aberrant inflammatory responses, ranging from cytokine storm to immune-suppression, were described in COVID-19 and no treatment was demonstrated to change the prognosis significantly. Therefore, there is an urgent need for understanding the underlying pathogenic mechanisms to guide therapeutic interventions. This study was designed to assess myeloid cell activation and phenotype leading to recovery in patients surviving severe COVID-19. We evaluated longitudinally patients with COVID-19 related respiratory insufficiency, stratified according to the need of intensive care unit admission (ICU, n = 11, and No-ICU, n = 9), and age and sex matched healthy controls (HCs, n = 11), by flow cytometry and a wide array of serum inflammatory/immune-regulatory mediators. All patients featured systemic immune-regulatory myeloid cell phenotype as assessed by both unsupervised and supervised analysis of circulating monocyte and dendritic cell subsets. Specifically, we observed a reduction of CD14lowCD16+ monocytes, and reduced expression of CD80, CD86, and Slan. Moreover, mDCs, pDCs, and basophils were significantly reduced, in comparison to healthy subjects. Contemporaneously, both monocytes and DCs showed increased expression of CD163, CD204, CD206, and PD-L1 immune-regulatory markers. The expansion of M2-like monocytes was significantly higher at admission in patients featuring detectable SARS-CoV-2 plasma viral load and it was positively correlated with the levels of specific antibodies. In No-ICU patients, we observed a peak of the alterations at admission and a progressive regression to a phenotype similar to HCs at discharge. Interestingly, in ICU patients, the expression of immuno-suppressive markers progressively increased until discharge. Notably, an increase of M2-like HLA-DRhighPD-L1+ cells in CD14++CD16- monocytes and in dendritic cell subsets was observed at ICU discharge. Furthermore, IFN-γ and IL-12p40 showed a decline over time in ICU patients, while high values of IL1RA and IL-10 were maintained. In conclusion, these results support that timely acquisition of a myeloid cell immune-regulatory phenotype might contribute to recovery in severe systemic SARS-CoV-2 infection and suggest that therapeutic agents favoring an innate immune system regulatory shift may represent the best strategy to be implemented at this stage.


Assuntos
COVID-19/imunologia , Monócitos/imunologia , Células Supressoras Mieloides/imunologia , SARS-CoV-2/fisiologia , Adulto , Idoso , Diferenciação Celular , Cuidados Críticos , Citocinas/metabolismo , Feminino , Humanos , Imunomodulação , Masculino , Pessoa de Meia-Idade , Fenótipo , Insuficiência Respiratória , Índice de Gravidade de Doença , Células Th2/imunologia
10.
Viruses ; 13(9)2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34578386

RESUMO

Monocytes are key modulators in acute viral infections, determining both inflammation and development of specific B- and T-cell responses. Recently, these cells were shown to be associated to different SARS-CoV-2 infection outcome. However, their role in acute HIV-1 infection remains unclear. We had the opportunity to evaluate the mononuclear cell compartment in an early hyper-acute HIV-1 patient in comparison with an untreated chronic HIV-1 and a cohort of SARS-CoV-2 infected patients, by high dimensional flow cytometry using an unsupervised approach. A distinct polarization of the monocyte phenotype was observed in the two viral infections, with maintenance of pro-inflammatory M1-like profile in HIV-1, in contrast to the M2-like immunosuppressive shift in SARS-CoV-2. Noticeably, both acute infections had reduced CD14low/-CD16+ non-classical monocytes, with depletion of the population expressing Slan (6-sulfo LacNac), which is thought to contribute to immune surveillance through pro-inflammatory properties. This depletion indicates a potential role of these cells in acute viral infection, which has not previously been explored. The inflammatory state accompanied by the depletion of Slan+ monocytes may provide new insights on the critical events that determine the rate of viral set-point in acute HIV-1 infection and subsequent impact on transmission and reservoir establishment.


Assuntos
Amino Açúcares/imunologia , COVID-19/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Monócitos/imunologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Cell Rep ; 36(9): 109574, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34469732

RESUMO

Neuroinflammation in patients with Alzheimer's disease (AD) and related mouse models has been recognized for decades, but the contribution of the recently described meningeal immune population to AD pathogenesis remains to be addressed. Here, using the 3xTg-AD model, we report an accumulation of interleukin-17 (IL-17)-producing cells, mostly γδ T cells, in the brain and the meninges of female, but not male, mice, concomitant with the onset of cognitive decline. Critically, IL-17 neutralization into the ventricles is sufficient to prevent short-term memory and synaptic plasticity deficits at early stages of disease. These effects precede blood-brain barrier disruption and amyloid-beta or tau pathology, implying an early involvement of IL-17 in AD pathology. When IL-17 is neutralized at later stages of disease, the onset of short-memory deficits and amyloidosis-related splenomegaly is delayed. Altogether, our data support the idea that cognition relies on a finely regulated balance of "inflammatory" cytokines derived from the meningeal immune system.


Assuntos
Doença de Alzheimer/metabolismo , Comportamento Animal , Encéfalo/metabolismo , Cognição , Mediadores da Inflamação/metabolismo , Interleucina-17/metabolismo , Linfócitos Intraepiteliais/metabolismo , Doenças Neuroinflamatórias/metabolismo , Sinapses/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/psicologia , Animais , Anti-Inflamatórios/farmacologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/antagonistas & inibidores , Interleucina-17/antagonistas & inibidores , Linfócitos Intraepiteliais/efeitos dos fármacos , Masculino , Memória de Curto Prazo , Camundongos da Linhagem 129 , Camundongos Transgênicos , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/prevenção & controle , Doenças Neuroinflamatórias/psicologia , Plasticidade Neuronal , Sinapses/efeitos dos fármacos , Sinapses/patologia
12.
Braz J Infect Dis ; 25(3): 101598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34280356

RESUMO

Hypovitaminosis D is now considered a pandemic, especially among more vulnerable populations and in HIV-infected subjects, with 80% presenting levels below 30 ng/mL. As there is no consensus on the more adequate dosage needed to correct such deficiency, the objective of this study was to evaluate 25 (OH) vitamin D supplementation in HIV-1 patients deficient of vitamin D. A total of 73 HIV-1-infected patients were included, drawn from a cohort of 435 patients; 37 patients were randomized to the active group, supplemented once a week with 50,000 UI vitamin D by mouth (group 1) and 36 to the placebo group (group 2). The study period ranged from June 2016 to September 2017. Variables involved in vitamin D metabolism and risk factors associated with hypovitaminosis were evaluated. The mean age was 45 years and 31.5 % were women. Vitamin D supplementation was effective in normalizing serum levels after six months in group 1 (mean 35 ng/mL compared to 21 ng/mL for the placebo group; p = 0.04). No patient reached blood levels considered toxic (>100 UI). Efavirenz use can negatively influence vitamin D levels and supplementation is necessary as a likely adjunct to improving CD4+ T cells, resulting in greater effectiveness of the treatment. A weekly oral dose of 50,000 IU of vitamin D was sufficient to normalize the vitamin deficiency, safely and with good adherence among persons living with HIV/AIDS in Brazil.


Assuntos
Síndrome da Imunodeficiência Adquirida , Deficiência de Vitamina D , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Brasil , Suplementos Nutricionais , Feminino , Humanos , Pessoa de Meia-Idade , Vitamina D , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/epidemiologia
13.
Nat Commun ; 12(1): 7268, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907175

RESUMO

Interleukin-7 receptor α (encoded by IL7R) is essential for lymphoid development. Whether acute lymphoblastic leukemia (ALL)-related IL7R gain-of-function mutations can trigger leukemogenesis remains unclear. Here, we demonstrate that lymphoid-restricted mutant IL7R, expressed at physiological levels in conditional knock-in mice, establishes a pre-leukemic stage in which B-cell precursors display self-renewal ability, initiating leukemia resembling PAX5 P80R or Ph-like human B-ALL. Full transformation associates with transcriptional upregulation of oncogenes such as Myc or Bcl2, downregulation of tumor suppressors such as Ikzf1 or Arid2, and major IL-7R signaling upregulation (involving JAK/STAT5 and PI3K/mTOR), required for leukemia cell viability. Accordingly, maximal signaling drives full penetrance and early leukemia onset in homozygous IL7R mutant animals. Notably, we identify 2 transcriptional subgroups in mouse and human Ph-like ALL, and show that dactolisib and sphingosine-kinase inhibitors are potential treatment avenues for IL-7R-related cases. Our model, a resource to explore the pathophysiology and therapeutic vulnerabilities of B-ALL, demonstrates that IL7R can initiate this malignancy.


Assuntos
Subunidade alfa de Receptor de Interleucina-7/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Mutação com Ganho de Função , Heterozigoto , Homozigoto , Humanos , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Camundongos , Penetrância , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Células Precursoras de Linfócitos B/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos
14.
Arq Neuropsiquiatr ; 79(12): 1109-1115, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34877984

RESUMO

BACKGROUND: The genetic predisposition to multiple sclerosis (MS) is associated with HLA alleles, especially HLA-DRB1*15:01. OBJECTIVE: To identify associations between findings in magnetic resonance imaging (MRI) and genetic features in a Brazilian cohort of patients with MS. METHODS: We retrospectively studied data from 95 consecutive patients with MS. Two independent observers who were blinded to the clinical data identified black holes and enhanced lesions on T1 MRI sequences, and counted and measured contrast-enhanced lesions on T2 and Flair (fluid attenuation inversion recovery) sequences. Cases were classified according to lesion size, number, and volume. The HLA-DRB1, HLA-DQB1, and HLA-DQA1 alleles, and the rs4774, rs3087456, rs6897932, rs731236, and rs1033182 single nucleotide polymorphisms were identified by polymerase chain reaction amplification with sequence-specific primers using the One Lambda Inc. Kit, Canoga Park, CA, USA. RESULTS: Patients with the HLA-DQA1*04:01 allele had lesion load (adjusted for age, sex, and MS duration) above median compared with patients with other HLA-DQA1 alleles (p=0.02). There were no differences among all the other HLA alleles and single nucleotide polymorphisms and lesion load. CONCLUSIONS: The correlation of the HLA-DQA1*04:01 allele with a higher lesion load on T2/Flair MRI sequences suggests that the presence of this allele is associated with the risk of greater MS severity.


Assuntos
Cadeias alfa de HLA-DQ/genética , Esclerose Múltipla , Alelos , Frequência do Gene , Genes MHC da Classe II , Predisposição Genética para Doença , Cadeias beta de HLA-DQ , Cadeias HLA-DRB1/genética , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/genética , Estudos Retrospectivos
15.
Malar J ; 8: 59, 2009 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-19358729

RESUMO

BACKGROUND: In response to chloroquine (CQ) resistance, the policy for the first-line treatment of uncomplicated malaria in the Democratic Republic of East Timor (DRET) was changed in early 2000. The combination of sulphadoxine-pyrimethamine (SP) was then introduced for the treatment of uncomplicated falciparum malaria. METHODS: Blood samples were collected in two different periods (2003-2004 and 2004-2005) from individuals attending hospitals or clinics in six districts of the DRET and checked for Plasmodium falciparum infection. 112 PCR-positive samples were inspected for genetic polymorphisms in the pfcrt, pfmdr1, pfdhfr and pfdhps genes. Different alleles were interrogated for potential associations that could be indicative of non-random linkage. RESULTS: Overall prevalence of mutations associated with resistance to CQ and SP was extremely high. The mutant form of Pfcrt (76T) was found to be fixed even after five years of alleged CQ removal. There was a significant increase in the prevalence of the pfdhps 437G mutation (X2 = 31.1; p = 0.001) from the first to second survey periods. A non-random association was observed between pfdhfr51/pfdhps437 (p = 0.001) and pfdhfr 59/pfdhps 437 (p = 0.013) alleles. CONCLUSION: Persistence of CQ-resistant mutants even after supposed drug withdrawal suggests one or all of the following: local P. falciparum may still be inadvertently exposed to the drug, that mutant parasites are being "imported" into the country, and/or reduced genetic diversity and low parasite transmission help maintain mutant haplotypes. The association between pfdhfr51/pfdhps437 and pfdhfr 59/pfdhps 437 alleles indicates that these are undergoing concomitant positive selection in the DRET.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Polimorfismo de Fragmento de Restrição/efeitos dos fármacos , Adolescente , Adulto , Alelos , Animais , Antimaláricos/uso terapêutico , Criança , Cloroquina/uso terapêutico , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Feminino , Genótipo , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Masculino , Mutação/efeitos dos fármacos , Mutação/genética , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição/genética , Proteínas de Protozoários/genética , Timor-Leste , Adulto Jovem
16.
Cell Signal ; 38: 10-25, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28645565

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological cancer that arises from clonal expansion of transformed T-cell precursors. In this review we summarize the current knowledge on the external stimuli and cell-intrinsic lesions that drive aberrant activation of pivotal, pro-tumoral intracellular signaling pathways in T-cell precursors, driving transformation, leukemia expansion, spread or resistance to therapy. In addition to their pathophysiological relevance, receptors and kinases involved in signal transduction are often attractive candidates for targeted drug development. As such, we discuss also the potential of T-ALL signaling players as targets for therapeutic intervention.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Transdução de Sinais , Animais , Humanos , Modelos Biológicos
18.
Clin Cancer Res ; 22(23): 5795-5804, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27307596

RESUMO

PURPOSE: The Vδ1+ subset of γδ T lymphocytes is a promising candidate for cancer immunotherapy, but the lack of suitable expansion/differentiation methods has precluded therapeutic application. We set out to develop and test (preclinically) a Vδ1+ T-cell-based protocol that is good manufacturing practice compatible and devoid of feeder cells for prompt clinical translation. EXPERIMENTAL DESIGN: We tested multiple combinations of clinical-grade agonist antibodies and cytokines for their capacity to expand and differentiate (more than 2-3 weeks) Vδ1+ T cells from the peripheral blood of healthy donors and patients with chronic lymphocytic leukemia (CLL). We characterized the phenotype and functional potential of the final cellular product, termed Delta One T (DOT) cells, in vitro and in vivo (xenograft models of CLL). RESULTS: We describe a very robust two-step protocol for the selective expansion (up to 2,000-fold in large clinical-grade cell culture bags) and differentiation of cytotoxic Vδ1+ (DOT) cells. These expressed the natural cytotoxicity receptors, NKp30 and NKp44, which synergized with the T-cell receptor to mediate leukemia cell targeting in vitro When transferred in vivo, DOT cells infiltrated tumors and peripheral organs, and persisted until the end of the analysis without showing signs of loss of function; indeed, DOT cells proliferated and produced abundant IFNγ and TNFα, but importantly no IL17, in vivo Critically, DOT cells were capable of inhibiting tumor growth and preventing dissemination in xenograft models of CLL. CONCLUSIONS: We provide a clinical-grade method and the preclinical proof of principle for application of a new cellular product, DOT cells, in adoptive immunotherapy of CLL. Clin Cancer Res; 22(23); 5795-804. ©2016 AACR.


Assuntos
Diferenciação Celular/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/terapia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica/imunologia , Feminino , Humanos , Imunoterapia Adotiva/métodos , Interferon gama/imunologia , Contagem de Linfócitos/métodos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Fator de Necrose Tumoral alfa/imunologia
19.
Arq. neuropsiquiatr ; 79(12): 1109-1115, Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1355702

RESUMO

ABSTRACT Background: The genetic predisposition to multiple sclerosis (MS) is associated with HLA alleles, especially HLA-DRB1*15:01. Objective: To identify associations between findings in magnetic resonance imaging (MRI) and genetic features in a Brazilian cohort of patients with MS. Methods: We retrospectively studied data from 95 consecutive patients with MS. Two independent observers who were blinded to the clinical data identified black holes and enhanced lesions on T1 MRI sequences, and counted and measured contrast-enhanced lesions on T2 and Flair (fluid attenuation inversion recovery) sequences. Cases were classified according to lesion size, number, and volume. The HLA-DRB1, HLA-DQB1, and HLA-DQA1 alleles, and the rs4774, rs3087456, rs6897932, rs731236, and rs1033182 single nucleotide polymorphisms were identified by polymerase chain reaction amplification with sequence-specific primers using the One Lambda Inc. Kit, Canoga Park, CA, USA. Results: Patients with the HLA-DQA1*04:01 allele had lesion load (adjusted for age, sex, and MS duration) above median compared with patients with other HLA-DQA1 alleles (p=0.02). There were no differences among all the other HLA alleles and single nucleotide polymorphisms and lesion load. Conclusions: The correlation of the HLA-DQA1*04:01 allele with a higher lesion load on T2/Flair MRI sequences suggests that the presence of this allele is associated with the risk of greater MS severity.


RESUMO Antecedentes: A predisposição genética para a esclerose múltipla (EM) está associada a alelos HLA, principalmente o HLA-DRB1*15:01. Objetivo: Identificar associações entre lesões na ressonância magnética e características genéticas em uma coorte brasileira de pacientes com EM. Métodos: Estudamos retrospectivamente os dados de 95 pacientes consecutivos com EM. Dois observadores independentes que desconheciam os dados clínicos identificaram "black holes" e lesões realçadas pelo contraste nas sequências de ressonância magnética T1 e contaram e mediram as lesões nas sequências T2 e FLAIR (fluid attenuated inversion recovery). Os casos foram classificados de acordo com tamanho, número e volume da lesão. Os alelos HLA-DRB1, HLA-DQB1 e HLA-DQA1 e os polimorfismos de nucleotídeo único rs4774, rs3087456, rs6897932, rs731236 e rs1033182 foram identificados por amplificação de reação em cadeia da polimerase com iniciadores específicos de sequência usando o kit One Lambda Inc., Canoga Park, CA, EUA. Resultados: Os pacientes com alelo HLA-DQA1*04:01 apresentaram carga de lesão (ajustada para idade, sexo e duração da EM) acima da mediana em comparação com outros pacientes com demais alelos HLA-DQA1 (p=0,02). Não houve diferenças entre todos os outros alelos HLA e polimorfismos de nucleotídeo único e carga lesional. Conclusões: A correlação do alelo HLA-DQA1*04:01 com maior carga de lesão nas sequências de RM em T2 sugere que a presença desse alelo pode estar associada ao risco de maior gravidade da EM.


Assuntos
Humanos , Cadeias alfa de HLA-DQ/genética , Esclerose Múltipla/genética , Esclerose Múltipla/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Genes MHC da Classe II , Predisposição Genética para Doença , Alelos , Cadeias beta de HLA-DQ , Cadeias HLA-DRB1/genética , Frequência do Gene
20.
Braz. j. infect. dis ; 25(3): 101598, 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1339421

RESUMO

ABSTRACT Hypovitaminosis D is now considered a pandemic, especially among more vulnerable populations and in HIV-infected subjects, with 80% presenting levels below 30 ng/mL. As there is no consensus on the more adequate dosage needed to correct such deficiency, the objective of this study was to evaluate 25 (OH) vitamin D supplementation in HIV-1 patients deficient of vitamin D. A total of 73 HIV-1-infected patients were included, drawn from a cohort of 435 patients; 37 patients were randomized to the active group, supplemented once a week with 50,000 UI vitamin D by mouth (group 1) and 36 to the placebo group (group 2). The study period ranged from June 2016 to September 2017. Variables involved in vitamin D metabolism and risk factors associated with hypovitaminosis were evaluated. The mean age was 45 years and 31.5 % were women. Vitamin D supplementation was effective in normalizing serum levels after six months in group 1 (mean 35 ng/mL compared to 21 ng/mL for the placebo group; p= 0.04). No patient reached blood levels considered toxic (>100 UI). Efavirenz use can negatively influence vitamin D levels and supplementation is necessary as a likely adjunct to improving CD4+ T cells, resulting in greater effectiveness of the treatment. A weekly oral dose of 50,000 IU of vitamin D was sufficient to normalize the vitamin deficiency, safely and with good adherence among persons living with HIV/AIDS in Brazil.


Assuntos
Humanos , Feminino , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/epidemiologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Vitamina D , Brasil , Suplementos Nutricionais , Pessoa de Meia-Idade
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