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1.
Eur J Cancer ; 104: 137-144, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30347289

RESUMO

BACKGROUND: Anti-programmed cell death protein 1/programmed death ligand 1 (PD-1/PD-L1) immunotherapy is now routinely used to treat several cancers. Clinical trials have excluded several populations, including patients with solid organ transplant, HIV infection and hepatitis B/C infection. We examined the safety outcomes of these populations treated with anti-PD-1/PD-L1 treatment in a multicentre retrospective study. METHODS: Patients from 16 centres with advanced cancer and solid organ transplant, HIV infection or hepatitis B/C infection were included. Demographic, tumour, treatment, toxicity and outcome data were recorded. RESULTS: Forty-six patients were included for analysis, with a median age of 60 years, and the majority of patients diagnosed with melanoma (72%). Among six patients with solid organ transplants, two graft rejections occurred, with one resulting in death, whereas two patients achieved partial responses. There were four responses in 12 patients with HIV infection. In 14 patients with hepatitis B, there were three responses, and similarly, there were three responses in 14 patients with hepatitis C. There was no unexpected toxicity in any viral infection group or an increase in viral load. CONCLUSION: Patients with HIV or hepatitis B/C infections treated with anti-PD-1/PD-L1 immunotherapy may respond to treatment without increased toxicity. Given the risk of graft rejection in solid organ transplant patients and also the potential for response, the role of anti-PD-1/PD-L1 immunotherapy needs to be carefully considered.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Infecções por HIV/complicações , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Imunoterapia , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Transplantados , Idoso , Antineoplásicos Imunológicos/efeitos adversos , Feminino , Rejeição de Enxerto/etiologia , Humanos , Imunoterapia/efeitos adversos , Masculino , Melanoma/complicações , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Terapia de Alvo Molecular/efeitos adversos , Neoplasias/complicações , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
2.
J Clin Immunol ; 38(7): 768-777, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30219982

RESUMO

Individuals with common variable immunodeficiency (CVID) have an increased risk of gastric cancer, and gastrointestinal lymphoma, yet screening for premalignant gastric lesions is rarely offered routinely to these patients. Proposed screening protocols are not widely accepted and are based on gastric cancer risk factors that are not applicable to all CVID patients. Fifty-two CVID patients were recruited for screening gastroscopy irrespective of symptoms or blood results and were compared to 40 controls presenting for gastroscopy for other clinical indications. Overall, 34% of CVID patients had intestinal metaplasia (IM), atrophic gastritis or moderate to severe non-atrophic gastritis, which can increase the risk of gastric cancer, compared to 7.5% of controls (p < 0.01). Focal nodular lymphoid hyperplasia, a precursor lesion for gastrointestinal lymphoma, was seen in eight CVID patients (16%), one of whom was diagnosed with gastrointestinal lymphoma on the same endoscopy. High-risk gastric pathology was associated with increased time since diagnosis of CVID, smoking, Helicobacter pylori, a low-serum pepsinogen I concentration, and diarrhea, but not pepsinogen I/II ratio, iron studies, vitamin B12 levels or upper gastrointestinal symptoms. There was a lower rate of detection of IM when fewer biopsies were taken, and IM and gastric atrophy were rarely predicted by the endoscopist macroscopically, highlighting the need for standardized biopsy protocols. The prevalence of premalignant gastric lesions in patients with CVID highlights the need for routine gastric screening. We propose a novel gastric screening protocol to detect early premalignant lesions and reduce the risk of gastric cancer and gastric lymphoma in these patients.


Assuntos
Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Biópsia , Imunodeficiência de Variável Comum/etiologia , Detecção Precoce de Câncer , Feminino , Gastrite Atrófica/complicações , Gastroscopia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Programas de Rastreamento , Metaplasia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões Pré-Cancerosas , Prevalência , Vigilância em Saúde Pública , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Inquéritos e Questionários , Adulto Jovem
3.
J Exp Med ; 215(8): 2073-2095, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-30018075

RESUMO

Gain-of-function (GOF) mutations in PIK3CD, encoding the p110δ subunit of phosphatidylinositide 3-kinase (PI3K), cause a primary immunodeficiency. Affected individuals display impaired humoral immune responses following infection or immunization. To establish mechanisms underlying these immune defects, we studied a large cohort of patients with PIK3CD GOF mutations and established a novel mouse model using CRISPR/Cas9-mediated gene editing to introduce a common pathogenic mutation in Pik3cd In both species, hyperactive PI3K severely affected B cell development and differentiation in the bone marrow and the periphery. Furthermore, PI3K GOF B cells exhibited intrinsic defects in class-switch recombination (CSR) due to impaired induction of activation-induced cytidine deaminase (AID) and failure to acquire a plasmablast gene signature and phenotype. Importantly, defects in CSR, AID expression, and Ig secretion were restored by leniolisib, a specific p110δ inhibitor. Our findings reveal key roles for balanced PI3K signaling in B cell development and long-lived humoral immunity and memory and establish the validity of treating affected individuals with p110δ inhibitors.


Assuntos
Linfócitos B/citologia , Linfócitos B/imunologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação em Linhagem Germinativa/genética , Fosfatidilinositol 3-Quinases/genética , Animais , Afinidade de Anticorpos/imunologia , Células da Medula Óssea/citologia , Diferenciação Celular , Proliferação de Células , Criança , Mutação com Ganho de Função/genética , Humanos , Switching de Imunoglobulina , Imunoglobulinas/metabolismo , Interleucinas/farmacologia , Camundongos , Modelos Animais , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Plasmócitos/metabolismo , Transdução de Sinais
4.
Front Immunol ; 9: 168, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29472924

RESUMO

Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that is activated downstream of many key cytokine receptors expressed by lymphocytes. As such, it plays a critical role in regulating B cells as well as CD4+ and CD8+ T cells. Patients with clinically significant immunodeficiency and immune dysregulation resulting from loss-of-function or gain-of-function mutations in STAT3 have been described. These individuals provide insight into the critical role of this transcription factor in the regulation of immune responses and the balance between effective immune protection and autoimmunity.


Assuntos
Linfócitos B/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Animais , Autoimunidade/genética , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Mutação com Ganho de Função , Humanos , Imunomodulação/genética , Mutação com Perda de Função , Fator de Transcrição STAT3/genética , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T/imunologia
6.
Immunol Cell Biol ; 94(8): 774-86, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27101923

RESUMO

Immunological memory is characterized by the rapid reactivation of memory B cells that produce large quantities of high-affinity antigen-specific antibodies. This contrasts the response of naïve B cells, and the primary immune response, which is much slower and of lower affinity. Memory responses are critical for protection against infectious diseases and form the basis of most currently available vaccines. Although we have known about the phenomenon of long-lived memory for centuries, the biochemical differences underlying these diverse responses of naïve and memory B cells is incompletely resolved. Here we investigated the nature of B-cell receptor (BCR) signaling in human splenic naïve, IgM(+) memory and isotype-switched memory B cells following multivalent BCR crosslinking. We observed comparable rapid and transient phosphorylation kinetics for proximal (phosphotyrosine and spleen tyrosine kinase) and propagation (B-cell linker, phospholipase Cγ2) signaling components in these different B-cell subsets. However, the magnitude of activation of downstream components of the BCR signaling pathway were greater in memory compared with naïve cells. Although no differences were observed in the magnitude of Ca(2+) mobilization between subsets, IgM(+) memory B cells exhibited a more rapid Ca(2+) mobilization and a greater depletion of the Ca(2+) endoplasmic reticulum stores, while IgG(+) memory B cells had a prolonged Ca(2+) uptake. Collectively, our findings show that intrinsic signaling features of B-cell subsets contribute to the robust response of human memory B cells over naïve B cells. This has implications for our understanding of memory B-cell responses and provides a framework to modulate these responses in the setting of vaccination and immunopathologies, such as immunodeficiency and autoimmunity.


Assuntos
Linfócitos B/imunologia , Memória Imunológica , Receptores de Antígenos de Linfócitos B/metabolismo , Subpopulações de Linfócitos B/imunologia , Cálcio/metabolismo , Ciclo Celular , Humanos , Imunoglobulina M/metabolismo , Cinética , Ativação Linfocitária/imunologia , Inibidor de NF-kappaB alfa/metabolismo , Fenótipo , Fosforilação , Proteólise , Transdução de Sinais , Baço/citologia
7.
Curr Opin Immunol ; 28: 49-57, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24594518

RESUMO

Signalling in lymphocytes through cytokine receptors is critical for their development, activation and differentiation into effector cells that mediate protection against pathogens and provide the host with protective immunological memory. The essential role of cytokine signalling has been established not only by the generation and examination of gene-targeted mice, but also 'Experiments of Nature' whereby monogenic mutations cause primary immunodeficient conditions characterised by impaired immunity to infectious diseases due to compromised lymphocyte function. Mutations in STAT3 cause autosomal dominant hyper-IgE syndrome. Here, we will review how the study of STAT3-deficient individuals has revealed non-redundant functions of STAT3 and specific cytokines in human lymphocyte biology, and have delineated mechanisms underlying the distinct clinical features of autosomal dominant hyper-IgE syndrome.


Assuntos
Diferenciação Celular , Linfócitos/imunologia , Fator de Transcrição STAT3/imunologia , Animais , Linfócitos B/imunologia , Humanos , Síndrome de Job/imunologia , Ativação Linfocitária , Linfócitos/citologia
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