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1.
Blood ; 137(17): 2326-2336, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33545713

RESUMO

Immunodysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is caused by mutations in forkhead box P3 (FOXP3), which lead to the loss of function of regulatory T cells (Tregs) and the development of autoimmune manifestations early in life. The selective induction of a Treg program in autologous CD4+ T cells by FOXP3 gene transfer is a promising approach for curing IPEX. We have established a novel in vivo assay of Treg functionality, based on adoptive transfer of these cells into scurfy mice (an animal model of IPEX) and a combination of cyclophosphamide (Cy) conditioning and interleukin-2 (IL-2) treatment. This model highlighted the possibility of rescuing scurfy disease after the latter's onset. By using this in vivo model and an optimized lentiviral vector expressing human Foxp3 and, as a reporter, a truncated form of the low-affinity nerve growth factor receptor (ΔLNGFR), we demonstrated that the adoptive transfer of FOXP3-transduced scurfy CD4+ T cells enabled the long-term rescue of scurfy autoimmune disease. The efficiency was similar to that seen with wild-type Tregs. After in vivo expansion, the converted CD4FOXP3 cells recapitulated the transcriptomic core signature for Tregs. These findings demonstrate that FOXP3 expression converts CD4+ T cells into functional Tregs capable of controlling severe autoimmune disease.


Assuntos
Doenças Autoimunes/prevenção & controle , Linfócitos T CD4-Positivos/imunologia , Ciclofosfamida/farmacologia , Fatores de Transcrição Forkhead/genética , Doenças Genéticas Ligadas ao Cromossomo X/prevenção & controle , Interleucina-2/farmacologia , Linfócitos T Reguladores/imunologia , Animais , Antineoplásicos/farmacologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/efeitos dos fármacos
2.
J Allergy Clin Immunol ; 149(2): 550-556.e2, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34800432

RESUMO

BACKGROUND: Severe coronavirus disease 2019 (COVID-19) is characterized by impaired type I interferon activity and a state of hyperinflammation leading to acute respiratory distress syndrome. The complement system has recently emerged as a key player in triggering and maintaining the inflammatory state, but the role of this molecular cascade in severe COVID-19 is still poorly characterized. OBJECTIVE: We aimed at assessing the contribution of complement pathways at both the protein and transcriptomic levels. METHODS: To this end, we systematically assessed the RNA levels of 28 complement genes in the circulating whole blood of patients with COVID-19 and healthy controls, including genes of the alternative pathway, for which data remain scarce. RESULTS: We found differential expression of genes involved in the complement system, yet with various expression patterns: whereas patients displaying moderate disease had elevated expression of classical pathway genes, severe disease was associated with increased lectin and alternative pathway activation, which correlated with inflammation and coagulopathy markers. Additionally, properdin, a pivotal positive regulator of the alternative pathway, showed high RNA expression but was found at low protein concentrations in patients with a severe and critical disease, suggesting its deposition at the sites of complement activation. Notably, low properdin levels were significantly associated with the use of mechanical ventilation (area under the curve = 0.82; P = .002). CONCLUSION: This study sheds light on the role of the alternative pathway in severe COVID-19 and provides additional rationale for the testing of drugs inhibiting the alternative pathway of the complement system.


Assuntos
COVID-19/imunologia , Ativação do Complemento/genética , Via Alternativa do Complemento/genética , Proteínas do Sistema Complemento/genética , Coagulação Intravascular Disseminada/imunologia , SARS-CoV-2/patogenicidade , COVID-19/genética , COVID-19/terapia , COVID-19/virologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/terapia , Doenças Cardiovasculares/virologia , Estudos de Casos e Controles , Comorbidade , Proteínas do Sistema Complemento/imunologia , Diabetes Mellitus/genética , Diabetes Mellitus/imunologia , Diabetes Mellitus/terapia , Diabetes Mellitus/virologia , Coagulação Intravascular Disseminada/genética , Coagulação Intravascular Disseminada/terapia , Coagulação Intravascular Disseminada/virologia , Feminino , Regulação da Expressão Gênica , Humanos , Hipertensão/genética , Hipertensão/imunologia , Hipertensão/terapia , Hipertensão/virologia , Lectinas/genética , Lectinas/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/virologia , Properdina/genética , Properdina/imunologia , Respiração Artificial , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Índice de Gravidade de Doença
3.
Am J Transplant ; 20(8): 2243-2253, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32065452

RESUMO

Acute graft-versus-host disease (GVHD) is a rare but frequently lethal complication after solid organ transplantation. GVHD occurs in unduly immunocompromised hosts but requires the escalation of immunosuppression, which does not discriminate between host and donor cells. In contrast, donor-targeted therapy would ideally mitigate graft-versus-host reactivity while sparing recipient immune functions. We report two children with end-stage renal disease and severe primary immune deficiency (Schimke syndrome) who developed severe steroid-resistant acute GVHD along with full and sustained donor T cell chimerism after isolated kidney transplantation. Facing a therapeutic dead end, we used a novel strategy based on the adoptive transfer of anti-HLA donor-specific antibodies (DSAs) through the transfusion of highly selected plasma. After approval by the appropriate regulatory authority, an urgent nationwide search was launched among more than 3800 registered blood donors with known anti-HLA sensitization. Adoptively transferred DSAs bound to and selectively depleted circulating donor T cells. The administration of DSA-rich plasma was well tolerated and notably did not induce antibody-mediated rejection of the renal allografts. Acute GVHD symptoms promptly resolved in one child. This report provides a proof of concept for a highly targeted novel therapeutic approach for solid organ transplantation-associated GVHD.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Rim , Criança , Doença Enxerto-Hospedeiro/etiologia , Humanos , Imunização Passiva , Transplante de Rim/efeitos adversos , Esteroides , Condicionamento Pré-Transplante
5.
Kidney Int Rep ; 8(3): 596-605, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36938085

RESUMO

Introduction: Exome sequencing (ES) has widened the field of nephrogenomics in adult nephrology. In addition to reporting the diagnostic yield of ES in an adult cohort study, we investigated the clinical implications of molecular diagnosis and developed a clinical score to predict the probability of obtaining positive result. Methods: From September 2018 we have used ES to prospectively perform a first-tier liberal exploration of adult nephropathies of unknown origin and/or when a genetic kidney disease was clinically suggested. We also analyzed copy number variant using the same assay. Results: Molecular diagnosis was made in 127 of 538 patients sequenced (diagnostic yield: 24%), comprising 47 distinct monogenic disorders. Eight of these monogenic disorders (17% [8/47]) accounted for 52% of genetic diagnoses. In 98% (n = 125/127) of the patients, the genetic information was reported to have major clinical implications. We developed a 4-value clinical score to predict the probability of obtaining a molecular diagnosis (area under the receiver operating characteristics curve [AUC] 0.726 [95% confidence interval: 0.670-0.782]) (available at http://allogenomics.com/score). Conclusion: This study reinforces the role of ES as a first-tier exploration for adult chronic kidney disease patients in whom phenotypes are often poor and atypical. Although external validation is required, our clinical score could be a useful tool for the implementation of nephrogenomics in adults.

6.
Front Immunol ; 12: 680567, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248962

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has affected millions of people worldwide. A clinical series of Kawasaki-like multisystem inflammatory syndrome (MIS), occurring after SARS-CoV-2 infection, have been described in children (MIS-C) and adults (MIS-A), but the pathophysiology remains unknown. CASE PRESENTATION: We describe a case of post-COVID-19 MIS-A in a 46-year-old man with biopsy-proven renal thrombotic microangiopathy (TMA). Specific complement inhibition with eculizumab was initiated promptly and led to a dramatic improvement of renal function. CONCLUSION: Our case suggests that that TMA could play a central role in the pathophysiology of post-COVID-19 MIS-A, making complement blockers an interesting therapeutic option.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/diagnóstico , Inativadores do Complemento/uso terapêutico , Rim/metabolismo , SARS-CoV-2/fisiologia , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Microangiopatias Trombóticas/diagnóstico , Humanos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Pandemias , Recuperação de Função Fisiológica , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Microangiopatias Trombóticas/tratamento farmacológico , Tratamento Farmacológico da COVID-19
7.
Nat Commun ; 12(1): 6446, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34750385

RESUMO

The use of chimeric antigen receptor (CAR)-engineered regulatory T cells (Tregs) has emerged as a promising strategy to promote immune tolerance. However, in conventional T cells (Tconvs), CAR expression is often associated with tonic signaling, which can induce CAR-T cell dysfunction. The extent and effects of CAR tonic signaling vary greatly according to the expression intensity and intrinsic properties of the CAR. Here, we show that the 4-1BB CSD-associated tonic signal yields a more dramatic effect in CAR-Tregs than in CAR-Tconvs with respect to activation and proliferation. Compared to CD28 CAR-Tregs, 4-1BB CAR-Tregs exhibit decreased lineage stability and reduced in vivo suppressive capacities. Transient exposure of 4-1BB CAR-Tregs to a Treg stabilizing cocktail, including an mTOR inhibitor and vitamin C, during ex vivo expansion sharply improves their in vivo function and expansion after adoptive transfer. This study demonstrates that the negative effects of 4-1BB tonic signaling in Tregs can be mitigated by transient mTOR inhibition.


Assuntos
Receptores de Antígenos Quiméricos/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Serina-Treonina Quinases TOR/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Antígeno HLA-A2/imunologia , Antígeno HLA-A2/metabolismo , Humanos , Imunossupressores/farmacologia , Imunoterapia Adotiva/métodos , Células Jurkat , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Transplante Heterólogo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
8.
EClinicalMedicine ; 28: 100590, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33173853

RESUMO

BACKGROUND: Complement pathway inhibition may provide benefit for severe acute respiratory illnesses caused by viral infections such as COVID-19. We present results from a nonrandomized proof-of-concept study of complement C5 inhibitor eculizumab for treatment of severe COVID-19. METHODS: All patients (N = 80) with confirmed SARS-CoV-2 infection and severe COVID-19 admitted to our intensive care unit between March 10 and May 5, 2020 were included. Forty-five patients were treated with standard care and 35 with standard care plus eculizumab through expanded-access emergency treatment. The prespecified primary outcome was day-15 survival. Clinical laboratory values and biomarkers, complement levels, and treatment-emergent serious adverse events (TESAEs) were also assessed. FINDINGS: At day 15, estimated survival was 82.9% (95% CI: 70.4%‒95.3%) with eculizumab and 62.2% (48.1%‒76.4%) without eculizumab (log-rank test, P = 0.04). Patients treated with eculizumab experienced a significantly more rapid decrease in lactate, blood urea nitrogen, total and conjugated bilirubin levels and a significantly more rapid increase in platelet count, prothrombin time, and in the ratio of arterial oxygen tension over fraction of inspired oxygen versus patients treated without eculizumab. Eculizumab-associated changes in complement levels, laboratory values, and biomarkers were consistent with terminal complement inhibition, reduced hypoxia, and decreased inflammation. TESAEs of special interest occurring in >5% of patients treated with/without eculizumab were ventilator-associated pneumonia (51%/24%), bacteremia (11%/2%), gastroduodenal hemorrhage (14%/16%), and hemolysis (3%/18%). INTERPRETATION: Findings from this proof-of-concept study suggest eculizumab may improve survival and reduce hypoxia in patients with severe COVID-19. Randomized studies evaluating the efficacy and safety of this treatment approach are needed. FUNDING: Programme d'Investissements d'Avenir: ANR-18-RHUS60004.

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