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1.
Nat Protoc ; 14(6): 1926-1943, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31101906

RESUMO

The identification of immunogenic neoantigens and their cognate T cells represents the most crucial and rate-limiting steps in the development of personalized cancer immunotherapies that are based on vaccination or on infusion of T cell receptor (TCR)-engineered T cells. Recent advances in deep-sequencing technologies and in silico prediction algorithms have allowed rapid identification of candidate neoepitopes. However, large-scale validation of putative neoepitopes and the isolation of reactive T cells are challenging because of the limited availablity of patient material and the low frequencies of neoepitope-specific T cells. Here we describe a standardized protocol for the induction of neoepitope-reactive T cells from healthy donor T cell repertoires, unaffected by the potentially immunosuppressive environment of the tumor-bearing host. Monocyte-derived dendritic cells (DCs) transfected with mRNA encoding candidate neoepitopes are used to prime autologous naive CD8+ T cells. Antigen-specific T cells that recognize endogenously processed and presented epitopes are detected using peptide-MHC (pMHC) multimers. Single multimer-positive T cells are sorted for the identification of TCR sequences, after an optional step that includes clonal expansion and functional characterization. The time required to identify neoepitope-specific T cells is 15 d, with an additional 2-4 weeks required for clonal expansion and downstream functional characterization. Identified neoepitopes and corresponding TCRs provide candidates for use in vaccination and TCR-based cancer immunotherapies, and datasets generated by this technology should be useful for improving algorithms to predict immunogenic neoantigens.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Epitopos/imunologia , Neoplasias/imunologia , Células Cultivadas , Células Dendríticas/metabolismo , Eletroporação/métodos , Epitopos/genética , Humanos , Imunoterapia/métodos , Neoplasias/terapia , RNA Mensageiro/genética , Receptores de Antígenos de Linfócitos T/análise , Receptores de Antígenos de Linfócitos T/imunologia , Transfecção/métodos
2.
J Allergy Clin Immunol Pract ; 7(6): 1970-1985.e4, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30877075

RESUMO

BACKGROUND: Although autoimmunity and hyperinflammation secondary to recombination activating gene (RAG) deficiency have been associated with delayed diagnosis and even death, our current understanding is limited primarily to small case series. OBJECTIVE: Understand the frequency, severity, and treatment responsiveness of autoimmunity and hyperinflammation in RAG deficiency. METHODS: In reviewing the literature and our own database, we identified 85 patients with RAG deficiency, reported between 2001 and 2016, and compiled the largest case series to date of 63 patients with prominent autoimmune and/or hyperinflammatory pathology. RESULTS: Diagnosis of RAG deficiency was delayed a median of 5 years from the first clinical signs of immune dysregulation. Most patients (55.6%) presented with more than 1 autoimmune or hyperinflammatory complication, with the most common etiologies being cytopenias (84.1%), granulomas (23.8%), and inflammatory skin disorders (19.0%). Infections, including live viral vaccinations, closely preceded the onset of autoimmunity in 28.6% of cases. Autoimmune cytopenias had early onset (median, 1.9, 2.1, and 2.6 years for autoimmune hemolytic anemia, immune thrombocytopenia, and autoimmune neutropenia, respectively) and were refractory to intravenous immunoglobulin, steroids, and rituximab in most cases (64.7%, 73.7%, and 71.4% for autoimmune hemolytic anemia, immune thrombocytopenia, and autoimmune neutropenia, respectively). Evans syndrome specifically was associated with lack of response to first-line therapy. Treatment-refractory autoimmunity/hyperinflammation prompted hematopoietic stem cell transplantation in 20 patients. CONCLUSIONS: Autoimmunity/hyperinflammation can be a presenting sign of RAG deficiency and should prompt further evaluation. Multilineage cytopenias are often refractory to immunosuppressive treatment and may require hematopoietic cell transplantation for definitive management.

4.
Sci Rep ; 8(1): 1765, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29379077

RESUMO

Serotonin is a monoamine neurotransmitter that signals through a wide array of receptors (5-HT1-7) many of which are also involved in immune processes. Dendritic cells (DCs) are crucial players in immune defense by bridging innate and adaptive immune responses via their vast repertoire of pattern recognition receptors and antigen-presenting capability. Although serotonin is known to influence immunity at many levels, cell type-specific expression and function of its receptors remains poorly understood. Here we aimed to study 5-HT1-7 expression and function in CD1a- and CD1a+ human monocyte-derived DCs (moDCs). We found that the 5-HT2B receptor-subtype is solely expressed by the inflammatory CD1a+ moDC subset. Specific 5-HT2B activation potently inhibited TLR2, TLR3, and TLR7/8-induced proinflammatory cytokine and chemokine (TNF-α, IL-6, IL-8, IP-10, IL-12) but not type I interferon-ß responses. 5-HT2B agonism also interfered with the polarization of CD1a+ moDC-primed CD4+ T cells towards inflammatory Th1 and Th17 effector lymphocytes. Here we report the subset-specific expression and immunomodulatory function of 5-HT2B in human moDCs. Our results expand the biological role of 5-HT2B which may act not only as a neurotransmitter receptor, but also as an important modulator of both innate and adaptive immune responses.


Assuntos
Células Dendríticas/imunologia , Fatores Imunológicos/imunologia , Receptor 5-HT2B de Serotonina/imunologia , Antígenos CD1/imunologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Células Cultivadas , Citocinas/imunologia , Humanos , Monócitos/imunologia , Transdução de Sinais/imunologia , Células Th17/imunologia
6.
J Allergy Clin Immunol Pract ; 4(6): 1089-1100, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27836058

RESUMO

A broad spectrum of autoimmunity is now well described in patients with primary immunodeficiencies (PIDs). Management of autoimmune disease in the background of PID is particularly challenging given the seemingly discordant goals of immune support and immune suppression. Our growing ability to define the molecular underpinnings of immune dysregulation has facilitated novel targeted therapeutics. This review focuses on mechanism-based treatment strategies for the most common autoimmune and inflammatory complications of PID including autoimmune cytopenias, rheumatologic disease, and gastrointestinal disease. We aim to provide guidance regarding the rational use of these agents in the complex PID patient population.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Gastroenteropatias/tratamento farmacológico , Síndromes de Imunodeficiência/tratamento farmacológico , Animais , Doenças Autoimunes/etiologia , Doenças Autoimunes/imunologia , Autoimunidade , Gastroenteropatias/etiologia , Gastroenteropatias/imunologia , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/imunologia
7.
Cell Signal ; 28(5): 335-347, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26829212

RESUMO

BACKGROUND: BRAF-mutant melanoma is characterized by aggressive metastatic potential and therapeutic resistance. The innate immune receptor RIG-I has emerged as a potential target in melanoma therapies but the contributing pathways involved in anti-cancer activity are poorly characterized. METHODS: Baseline and ATRA-induced expression of RIG-I in nine (3 wild type and 6 BRAF-mutant) melanoma cell lines was measured with Q-PCR and Western blot. Ligand-specific stimulation of RIG-I was detected by Q-PCR and ELISA. Activation of the RIG-I-coupled IRF3, NF-κB and MAPK pathways was tested with protein array and Western blot. Cell proliferation and apoptosis was monitored by flow cytometry and cell counting. Down modulation of MKP-1 expression in melanoma cells was performed by specific siRNA. RESULTS: Short-term ATRA pre-treatment increases the expression of RIG-I in BRAF-mutant melanoma cells. Specific activation of RIG-I by 5'ppp-dsRNA leads to increased activity of the IRF3-IFNß pathway but does not influence NF-κB signaling. RIG-I mediates the targeted dephosphorylation of several MAPKs (p38, RSK1, GSK-3α/ß, HSP27) via the endogenous regulator MKP-1 resulting in decreased melanoma cell proliferation. CONCLUSION: RIG-I has the potential to exert anticancer activity in BRAF-mutant melanoma via controlling IFNß production and MAPK signaling. This is the first study showing that RIG-I activation results in MKP-1-mediated inhibition of cell proliferation via controlling the p38-HSP27, c-Jun and rpS6 pathways thus identifying RIG-I and MKP-1 as novel and promising therapeutical targets.


Assuntos
Proteína DEAD-box 58/metabolismo , Fosfatase 1 de Especificidade Dupla/metabolismo , Sistema de Sinalização das MAP Quinases , Melanoma/enzimologia , Proteínas Proto-Oncogênicas B-raf/genética , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Humanos , Fator Regulador 3 de Interferon/metabolismo , Melanoma/genética , Melanoma/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Tretinoína/farmacologia
8.
Int J Mol Sci ; 16(8): 18412-38, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26262612

RESUMO

Mature and developing chondrocytes exist in a microenvironment where mechanical load, changes of temperature, osmolarity and acidic pH may influence cellular metabolism. Polymodal Transient Receptor Potential Vanilloid (TRPV) receptors are environmental sensors mediating responses through activation of linked intracellular signalling pathways. In chondrogenic high density cultures established from limb buds of chicken and mouse embryos, we identified TRPV1, TRPV2, TRPV3, TRPV4 and TRPV6 mRNA expression with RT-PCR. In both cultures, a switch in the expression pattern of TRPVs was observed during cartilage formation. The inhibition of TRPVs with the non-selective calcium channel blocker ruthenium red diminished chondrogenesis and caused significant inhibition of proliferation. Incubating cell cultures at 41 °C elevated the expression of TRPV1, and increased cartilage matrix production. When chondrogenic cells were exposed to mechanical load at the time of their differentiation into matrix producing chondrocytes, we detected increased mRNA levels of TRPV3. Our results demonstrate that developing chondrocytes express a full palette of TRPV channels and the switch in the expression pattern suggests differentiation stage-dependent roles of TRPVs during cartilage formation. As TRPV1 and TRPV3 expression was altered by thermal and mechanical stimuli, respectively, these are candidate channels that contribute to the transduction of environmental stimuli in chondrogenic cells.


Assuntos
Condrócitos/metabolismo , Condrogênese , Canais de Cátion TRPV/metabolismo , Animais , Cartilagem/citologia , Cartilagem/fisiologia , Técnicas de Cultura de Células , Células Cultivadas , Embrião de Galinha , Condrócitos/citologia , Condrogênese/efeitos dos fármacos , Temperatura Alta , Camundongos , RNA Mensageiro/genética , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/genética , Transcriptoma , Suporte de Carga
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