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1.
Immunogenetics ; 75(4): 369-383, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37322230

RESUMO

Though binding sites for the complement factor C1q and the canonical fragment crystallizable (Fc) gamma receptors (Fc[Formula: see text]Rs) on immunoglobulin G (IgG) molecules overlap, how C1q decoration of immune complexes (ICs) influences their ability to engage Fc[Formula: see text]Rs remains unknown. In this report, we use recombinant human Fc multimers as stable IC mimics to show that C1q engagement of ICs directly and transiently inhibits their interactions with Fc[Formula: see text]RIII (CD16) on human natural killer (NK) cells. This inhibition occurs by C1q engagement alone as well as in concert with other serum factors. Furthermore, the inhibition of Fc[Formula: see text]RIII engagement mediated by avid binding of C1q to ICs is directly associated with IC size and dependent on the concentrations of both C1q and Fc multimers present. Functionally, C1q-mediated Fc blockade limits the ability of NK cells to induce the upregulation of the cosignaling molecule, 4-1BB (CD137), and to mediate antibody-dependent cell-mediated cytotoxicity (ADCC). Although C1q is traditionally viewed as a soluble effector molecule, we demonstrate that C1q may also take on the role of an "immunologic rheostat," buffering Fc[Formula: see text]R-mediated activation of immune cells by circulating ICs. These data define a novel role for C1q as a regulator of immune homeostasis and add to our growing understanding that complement factors mediate pleiotropic effects.


Assuntos
Complemento C1q , Receptores de IgG , Humanos , Complemento C1q/metabolismo , Imunoglobulina G , Citotoxicidade Celular Dependente de Anticorpos , Células Matadoras Naturais
2.
J Immunol ; 196(3): 1165-76, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26695368

RESUMO

We developed a fully recombinant anti-CD20 protein derived from cDNA encoding one Fab domain, two IgG1 Fc regions, the IgG2 hinge, and an isoleucine zipper. This protein, called GB4542, contained both the homodimer and higher-order multimers. Binding studies revealed that GB4542 preferentially bound CD20(+) cells yet also recognized CD20(-)FcγR(+) PBMC. In contrast, a control mAb containing the identical Fab region, GB4500, failed to bind CD20(-)FcγR(+) PBMC. Consistent with these findings, interactions between GB4542 and the canonical FcγRs had substantially lower KD values than correlate interfaces between GB4500 and these receptors. At low concentrations, GB4542 showed enhanced Ab-dependent cellular cytotoxicity, Ab-dependent cellular phagocytosis, and complement-dependent cytotoxicity compared with GB4500. However, at higher concentrations, an Fc analog of GB4542 inhibited anti-CD20 mAb-mediated B cell clearance through direct blocking of both Fc-FcγR interactions and C1q deposition on target cells. Furthermore, the higher-order multimer fraction of GB4542 demonstrated greater binding avidity with the canonical FcγRs and was associated with inhibitory effects observed in Ab-dependent cellular phagocytosis and complement-dependent cytotoxicity assays. These data suggest that GB4542 might have utility in the treatment of autoimmune diseases by combining both mAb-mediated B cell depletion and multimerized Fc-mediated tolerogenic effects.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD20/imunologia , Linfócitos B/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Doenças Autoimunes/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/imunologia , Receptores de IgG/imunologia , Proteínas Recombinantes/imunologia , Ressonância de Plasmônio de Superfície
3.
Cancer ; 123(7): 1259-1271, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27906454

RESUMO

Recent advances have permitted successful therapeutic targeting of the immune system in head and neck squamous cell carcinoma (HNSCC). These new immunotherapeutic targets and agents are being rapidly adopted by the oncologic community and hold considerable promise. The National Cancer Institute sponsored a Clinical Trials Planning Meeting to address the issue of how to further investigate the use of immunotherapy in patients with HNSCC. The goals of the meeting were to consider phase 2 or 3 trial designs primarily in 3 different patient populations: those with previously untreated, human papillomavirus-initiated oropharyngeal cancers; those with previously untreated, human papillomavirus-negative HNSCC; and those with recurrent/metastatic HNSCC. In addition, a separate committee was formed to develop integrative biomarkers for the clinical trials. The meeting started with an overview of key immune components and principles related to HNSCC, including immunosurveillance and immune escape. Four clinical trial concepts were developed at the meeting integrating different immunotherapies with existing standards of care. These designs were presented for implementation by the head and neck committees of the National Cancer Institute-funded National Clinical Trials Network. This article summarizes the proceedings of this Clinical Trials Planning Meeting, the purpose of which was to facilitate the rigorous development and design of randomized phase 2 and 3 immunotherapeutic trials in patients with HNSCC. Although reviews usually are published immediately after the meeting is held, this report is unique because there are now tangible clinical trial designs that have been funded and put into practice and the studies are being activated to accrual. Cancer 2017;123:1259-1271. © 2016 American Cancer Society.


Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Imunoterapia , Anticorpos Monoclonais/uso terapêutico , Ensaios Clínicos como Assunto , Terapia Combinada , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia/efeitos adversos , Imunoterapia/métodos , Terapia de Alvo Molecular , National Cancer Institute (U.S.) , Estadiamento de Neoplasias , Seleção de Pacientes , Resultado do Tratamento , Estados Unidos
4.
J Autoimmun ; 84: 97-108, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28830653

RESUMO

There is a lack of effective targeted therapies for the treatment of complement dependent diseases. We developed two recombinant Fc multimers, G207 and G211, with limited ability to interact with low/moderate affinity FcγRs, but with high avidity for C1q. These drugs effectively inhibited complement dependent cytotoxicity (CDC) in vitro, and prevented the deposition of C1q, C3b and MAC, on the surface of Ab-opsonized cells. Importantly, these inhibitory effects were both C1q dependent and independent. In order to determine the biologic relevance of our findings, we evaluated the clinical efficacy of these drugs in three different animal models, acute RBC hemolysis, anti-Thy-1 nephritis and passive Heymann's nephropathy (PHN), in which disease pathophysiology relies preferentially on complement activation. While G207 was protective in the anti-Thy-1 nephritis and PHN models, G211 was protective in all of the models tested and could effectively treat PHN. In the anti-Thy-1 nephritis model, G211 prevented the characteristic histologic changes associated with the disease and limited glomerular deposition of C3. Collectively, these data suggest that "complement preferential" Fc multimers offer a novel approach to the treatment of complement mediated diseases.


Assuntos
Complemento C1q/imunologia , Proteínas do Sistema Complemento/metabolismo , Eritrócitos/fisiologia , Doenças do Sistema Imunitário/terapia , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Animais , Células Cultivadas , Complemento C3/metabolismo , Proteínas do Sistema Complemento/imunologia , Citotoxicidade Imunológica , Modelos Animais de Doenças , Glomerulonefrite Membranosa , Hemólise , Humanos , Doenças do Sistema Imunitário/imunologia , Terapia de Alvo Molecular , Ligação Proteica , Multimerização Proteica , Receptores Fc/metabolismo , Antígenos Thy-1/imunologia , Transgenes/genética
5.
Cancer Immunol Immunother ; 64(3): 367-79, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25537079

RESUMO

BACKGROUND: We conducted a phase I dose escalation study to evaluate the safety and immunologic response to peptide immunomodulatory vaccines GL-0810 (HPV16) and GL-0817 (MAGE-A3) in HPV16 and MAGE-A3-positive RM-SCCHN patients, respectively. METHODS: Three dose levels (500, 1,000, and 1,500 µg) of GL-0810 or GL-0817 with adjuvants Montanide (1.2 ml) and GM-CSF (100 µg/m2) were administered subcutaneously q2 weeks for a total of four vaccinations in HPV16 and MAGE-A3-positive RM-SCCHN patients, respectively. RESULTS: Nine and seven patients were enrolled in the HPV16 and MAGE-A3 cohorts, respectively. No dose-limiting toxicities were observed, and toxicity was predominantly local and grade 1 (erythema, pain, and itching at the injection site). In those patients who received all four vaccinations, 80 % (4/5) of the HPV16 cohort and 67 % (4/6) of the MAGE-A3 cohort developed antigen-specific T cell and antibody responses to the vaccine. Significant concordance between T cell and antibody responses was observed for both groups. No clear dose-response correlation was seen. All patients progressed by RECIST at first repeat imaging, except for one patient in the MAGE-A3 500 µg cohort who had stable disease for 10.5 months. The median PFS and OS for the MAGE-A3 cohorts were 79 and 183 days, respectively, and for the HPV16 cohort 80 and 196 days, respectively. CONCLUSIONS: GL-0810 and GL-0817 were well tolerated in patients with RM-SCCHN with T cell and antibody responses observed in the majority of patients who received all four vaccinations.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/administração & dosagem , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Papillomavirus Humano 16/imunologia , Fatores Imunológicos/administração & dosagem , Proteínas de Neoplasias/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Adulto , Idoso , Vacinas Anticâncer/imunologia , Carcinoma de Células Escamosas/imunologia , Estudos de Coortes , Progressão da Doença , Relação Dose-Resposta Imunológica , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Fatores Imunológicos/imunologia , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço , Vacinas de Subunidades Antigênicas/imunologia
6.
Cytokine ; 72(1): 48-57, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25569376

RESUMO

Invariant natural killer T (iNKT) cells constitute an important subset of T cells that can both directly and indirectly mediate anti-tumor immunity. However, cancer patients have a reduction in both iNKT cell number and function, and these deficits limit the potential clinical application of iNKT cells for cancer therapy. To overcome the problem of limited iNKT cell numbers, we investigated whether iNKT cells can be generated in vitro from bone marrow-derived adult hematopoietic stem-progenitor cells (HSPC). Our data demonstrate that co-culture of HSPC with OP9-DL1 stromal cells, results in a functional CD3(+) T cell population. These T cells can be further differentiated into iNKT cells by secondary culture with CD1d-Ig-based artificial antigen-presenting cells (aAPC). Importantly, these in vitro-generated iNKT cells are functional, as demonstrated by their ability to proliferate and secrete IFN-γ and GM-CSF following stimulation.


Assuntos
Células-Tronco Hematopoéticas/fisiologia , Ativação Linfocitária , Células T Matadoras Naturais/imunologia , Adulto , Células Apresentadoras de Antígenos/imunologia , Antígenos CD1d/imunologia , Diferenciação Celular , Técnicas de Cocultura , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Células-Tronco Hematopoéticas/citologia , Humanos , Interferon gama/metabolismo , Células T Matadoras Naturais/citologia , Células Estromais/imunologia
7.
J Immunol ; 190(12): 6015-22, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23686494

RESUMO

Altered B cell function is important in the pathogenesis of rheumatoid arthritis (RA). In this report, we show that patients with active RA have an increased frequency of CD32B low/neg cells in the CD27(+)IgD(-) memory B cell subset and that these changes are associated with phenotypic and functional B cell activation. Studies using PBMCs from healthy donors revealed that downregulation of CD32B on B cells is mediated by CD40-CD40L interactions and is potentiated by IL-4 and inhibited by both IL-10 and IL-21. These findings appear physiologically relevant because CD4 T cell expression of CD40L correlated with the frequency of CD32B low/neg cells in the CD27(+)IgD(-) memory B subset in patients with RA. Our data support a model in which high levels of CD40L, present on circulating T cells in patients with RA, causes B cell activation and CD32B downregulation, resulting in secondary protection of memory B cells from CD32B-mediated cell death.


Assuntos
Artrite Reumatoide/imunologia , Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Antígenos CD40/imunologia , Receptores de IgG/imunologia , Adulto , Idoso , Artrite Reumatoide/metabolismo , Subpopulações de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Antígenos CD40/metabolismo , Ligante de CD40/imunologia , Ligante de CD40/metabolismo , Regulação para Baixo , Feminino , Citometria de Fluxo , Humanos , Memória Imunológica/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Receptores de IgG/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
J Immunol ; 190(9): 4899-909, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23536636

RESUMO

Recurrent solid malignancies are often refractory to standard therapies. Although adoptive T cell transfer may benefit select individuals, the majority of patients succumb to their disease. To address this important clinical dilemma, we developed a mouse melanoma model in which initial regression of advanced disease was followed by tumor recurrence. During recurrence, Foxp3(+) tumor-specific CD4(+) T cells became PD-1(+) and represented >60% of the tumor-specific CD4(+) T cells in the host. Concomitantly, tumor-specific CD4(+) T effector cells showed traits of chronic exhaustion, as evidenced by their high expression of the PD-1, TIM-3, 2B4, TIGIT, and LAG-3 inhibitory molecules. Although blockade of the PD-1/PD-L1 pathway with anti-PD-L1 Abs or depletion of tumor-specific regulatory T cells (Tregs) alone failed to reverse tumor recurrence, the combination of PD-L1 blockade with tumor-specific Treg depletion effectively mediated disease regression. Furthermore, blockade with a combination of anti-PD-L1 and anti-LAG-3 Abs overcame the requirement to deplete tumor-specific Tregs. In contrast, successful treatment of primary melanoma with adoptive cell therapy required only Treg depletion or Ab therapy, underscoring the differences in the characteristics of treatment between primary and relapsing cancer. These data highlight the need for preclinical development of combined immunotherapy approaches specifically targeting recurrent disease.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Melanoma Experimental/imunologia , Recidiva Local de Neoplasia/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação/imunologia , Antígenos de Diferenciação/metabolismo , Proteínas Reguladoras de Apoptose/imunologia , Proteínas Reguladoras de Apoptose/metabolismo , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Receptor de Morte Celular Programada 1 , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Proteína do Gene 3 de Ativação de Linfócitos
9.
Cancer Immunol Immunother ; 63(9): 947-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24927849

RESUMO

Agonistic monoclonal antibodies (mAbs) directed against the co-signaling molecule CD137 (4-1BB) elicit potent anti-tumor immunity in mice. This anti-tumor immunity has traditionally been thought to result from the ability of the Fab portion of anti-CD137 to function as an analog for CD137L. Although binding of CD137 by anti-CD137 mAbs has the potential to cross-link the Fc fragments, enabling Fc engagement of low to moderate affinity Fc gamma receptors (FcγR), the relative import of such Fc-FcγR interactions in mediating anti-CD137 associated anti-tumor immunity is unknown. We studied the ability of a rat anti-mouse CD137 mAb (2A) to mediate the anti-tumor response against the EL4E7 lymphoma in WT and FcγR(-/-) strains. 2A-treated FcRγ(-/-) mice had improved anti-tumor immunity against EL4E7, which could be completely recapitulated in FcγRIII(-/-) animals. These improved anti-tumor responses were associated with increased splenic CD8ß T cell and dendritic cell (DC) populations. Furthermore, there was an increase in the number of DCs expressing high levels of the CD40, CD80, and CD86 molecules that are associated with more effective antigen presentation. Our results demonstrate an unexpected inhibitory role for FcγRIII in the anti-tumor function of anti-CD137 and underscore the need to consider antibody isotype when engineering therapeutic mAbs.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Linfoma/terapia , Receptores de IgG/deficiência , Receptores de IgG/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Anticorpos Imobilizados/imunologia , Anticorpos Imobilizados/metabolismo , Anticorpos Monoclonais/metabolismo , Feminino , Células HEK293 , Humanos , Linfoma/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Ratos , Receptores de IgG/metabolismo , Transfecção , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/biossíntese , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética
10.
PLoS Genet ; 7(9): e1002307, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21980308

RESUMO

Heterozygous Twirler (Tw) mice develop obesity and circling behavior associated with malformations of the inner ear, whereas homozygous Tw mice have cleft palate and die shortly after birth. Zeb1 is a zinc finger protein that contributes to mesenchymal cell fate by repression of genes whose expression defines epithelial cell identity. This developmental pathway is disrupted in inner ears of Tw/Tw mice. The purpose of our study was to comprehensively characterize the Twirler phenotype and to identify the causative mutation. The Tw/+ inner ear phenotype includes irregularities of the semicircular canals, abnormal utricular otoconia, a shortened cochlear duct, and hearing loss, whereas Tw/Tw ears are severely malformed with barely recognizable anatomy. Tw/+ mice have obesity associated with insulin-resistance and have lymphoid organ hypoplasia. We identified a noncoding nucleotide substitution, c.58+181G>A, in the first intron of the Tw allele of Zeb1 (Zeb1(Tw)). A knockin mouse model of c.58+181G>A recapitulated the Tw phenotype, whereas a wild-type knockin control did not, confirming the mutation as pathogenic. c.58+181G>A does not affect splicing but disrupts a predicted site for Myb protein binding, which we confirmed in vitro. In comparison, homozygosity for a targeted deletion of exon 1 of mouse Zeb1, Zeb1(ΔEx1), is associated with a subtle abnormality of the lateral semicircular canal that is different than those in Tw mice. Expression analyses of E13.5 Twirler and Zeb1(ΔEx1) ears confirm that Zeb1(ΔEx1) is a null allele, whereas Zeb1(Tw) RNA is expressed at increased levels in comparison to wild-type Zeb1. We conclude that a noncoding point mutation of Zeb1 acts via a gain-of-function to disrupt regulation of Zeb1(Tw) expression, epithelial-mesenchymal cell fate or interactions, and structural development of the inner ear in Twirler mice. This is a novel mechanism underlying disorders of hearing or balance.


Assuntos
Anormalidades Múltiplas/genética , Orelha Interna/anormalidades , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Íntrons/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Obesidade/genética , Animais , Sítios de Ligação/genética , Proteínas de Transporte/genética , Mapeamento Cromossômico , Proteínas de Ligação a DNA/genética , Transição Epitelial-Mesenquimal/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Introdução de Genes , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Fenótipo , Mutação Puntual/genética , RNA não Traduzido/genética , Proteínas de Ligação a RNA , Fatores de Transcrição , Homeobox 1 de Ligação a E-box em Dedo de Zinco
11.
PLoS Genet ; 7(9): e1002309, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21980309

RESUMO

Cellular heterogeneity hinders the extraction of functionally significant results and inference of regulatory networks from wide-scale expression profiles of complex mammalian organs. The mammalian inner ear consists of the auditory and vestibular systems that are each composed of hair cells, supporting cells, neurons, mesenchymal cells, other epithelial cells, and blood vessels. We developed a novel protocol to sort auditory and vestibular tissues of newborn mouse inner ears into their major cellular components. Transcriptome profiling of the sorted cells identified cell type-specific expression clusters. Computational analysis detected transcription factors and microRNAs that play key roles in determining cell identity in the inner ear. Specifically, our analysis revealed the role of the Zeb1/miR-200b pathway in establishing epithelial and mesenchymal identity in the inner ear. Furthermore, we detected a misregulation of the ZEB1 pathway in the inner ear of Twirler mice, which manifest, among other phenotypes, malformations of the auditory and vestibular labyrinth. The association of misregulation of the ZEB1/miR-200b pathway with auditory and vestibular defects in the Twirler mutant mice uncovers a novel mechanism underlying deafness and balance disorders. Our approach can be employed to decipher additional complex regulatory networks underlying other hearing and balance mouse mutants.


Assuntos
Orelha Interna/embriologia , Proteínas de Homeodomínio/fisiologia , Fatores de Transcrição Kruppel-Like/fisiologia , MicroRNAs/fisiologia , Morfogênese/genética , Animais , Surdez/genética , Surdez/metabolismo , Orelha Interna/anatomia & histologia , Células Epiteliais/citologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Fatores de Transcrição Kruppel-Like/genética , Mesoderma/citologia , Mesoderma/embriologia , Camundongos , Camundongos Endogâmicos ICR , MicroRNAs/genética , MicroRNAs/metabolismo , Vestíbulo do Labirinto/embriologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco
12.
Cell Rep Med ; 5(3): 101469, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38508137

RESUMO

Fibrolamellar carcinoma (FLC) is a liver tumor with a high mortality burden and few treatment options. A promising therapeutic vulnerability in FLC is its driver mutation, a conserved DNAJB1-PRKACA gene fusion that could be an ideal target neoantigen for immunotherapy. In this study, we aim to define endogenous CD8 T cell responses to this fusion in FLC patients and evaluate fusion-specific T cell receptors (TCRs) for use in cellular immunotherapies. We observe that fusion-specific CD8 T cells are rare and that FLC patient TCR repertoires lack large clusters of related TCR sequences characteristic of potent antigen-specific responses, potentially explaining why endogenous immune responses are insufficient to clear FLC tumors. Nevertheless, we define two functional fusion-specific TCRs, one of which has strong anti-tumor activity in vivo. Together, our results provide insights into the fragmented nature of neoantigen-specific repertoires in humans and indicate routes for clinical development of successful immunotherapies for FLC.


Assuntos
Carcinoma Hepatocelular , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/patologia , Terapia Baseada em Transplante de Células e Tecidos , Proteínas de Choque Térmico HSP40/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética
13.
J Craniofac Surg ; 24(4): 1273-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23851786

RESUMO

Neurofibromatosis type 1 is a rare, autosomal dominant disorder than can present with varying degrees of disfigurement depending on the associated tumor extent and location. Surgical resection is considered the most effective management of these typically benign tumors, indicated when symptoms include pain, extreme deformity, or interference with normal physical function. Giant tumors of the craniofacial region present particular difficulty due to the size of the post-resection wound deficit and the high risk surgery poses to function such as vision and facial animation in this region. Strategies of management are discussed.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/cirurgia , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/cirurgia , Adulto , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Neurofibromatose 1/patologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/cirurgia , Reoperação , Pele/patologia
14.
Front Immunol ; 14: 1199747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638040

RESUMO

Multiple Sclerosis (MS) is a chronic neurodegenerative disease with limited therapeutic options. Recombinant Fc multimers (rFc), designed to mirror many of the anti-inflammatory activities of Intravenous Immunoglobulin (IVIG), have been shown to effectively treat numerous immune-mediated diseases in rodents. In this study we used the experimental autoimmune encephalomyelitis (EAE) murine model of MS to test the efficacy of a rFc, M019, that consists of multimers of the Fc portion of IgG2, in inhibiting disease severity. We show that M019 effectively reduced clinical symptoms when given either pre- or post-symptom onset compared to vehicle treated EAE induced mice. M019 was effective in reducing symptoms in both SJL model of relapsing remitting MS as well as the B6 model of chronic disease. M019 binds to FcγR bearing-monocytes both in vivo and in vitro and prevented immune cell infiltration into the CNS of treated mice. The lack of T cell infiltration into the spinal cord was not due to a decrease in T cell priming; there was an equivalent frequency of Th17 cells in the spleens of M019 and vehicle treated EAE induced mice. Surprisingly, there was an increase in chemokines in the sera but not in the CNS of M019 treated mice compared to vehicle treated animals. We postulate that M019 interacts with a FcγR rich monocyte intermediary to prevent T cell migration into the CNS and demyelination.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Doenças Neurodegenerativas , Animais , Camundongos , Esclerose Múltipla/tratamento farmacológico , Modelos Animais de Doenças , Receptores de IgG
15.
Cancer Immunol Immunother ; 61(2): 203-214, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21877247

RESUMO

Genetic engineering of tumor cells to express immune-stimulatory molecules, including cytokines and co-stimulatory ligands, is a promising approach to generate highly efficient cancer vaccines. The co-signaling molecule, LIGHT, is particularly well suited for use in vaccine development as it delivers a potent co-stimulatory signal through the Herpes virus entry mediator (HVEM) receptor on T cells and facilitates tumor-specific T cell immunity. However, because LIGHT binds two additional receptors, lymphotoxin ß receptor and Decoy receptor 3, there are significant concerns that tumor-associated LIGHT results in both unexpected adverse events and interference with the ability of the vaccine to enhance antitumor immunity. In order to overcome these problems, we generated tumor cells expressing the single-chain variable fragment (scFv) of anti-HVEM agonistic mAb on the cell surface. Tumor cells expressing anti-HVEM scFv induce a potent proliferation and cytokine production of co-cultured T cells. Inoculation of anti-HVEM scFv-expressing tumor results in a spontaneous tumor regression in CD4+ and CD8+ T cell-dependent fashion, associated with the induction of tumor-specific long-term memory. Stimulation of HVEM and 4-1BB co-stimulatory signals by anti-HVEM scFv-expressing tumor vaccine combined with anti-4-1BB mAb shows synergistic effects which achieve regression of pre-established tumor and T cell memory specific to parental tumor. Taken in concert, our data suggest that genetic engineering of tumor cells to selectively potentiate the HVEM signaling pathway is a promising antitumor vaccine therapy.


Assuntos
Anticorpos Monoclonais/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Vacinas Anticâncer , Anticorpos de Cadeia Única/metabolismo , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Engenharia Genética , Humanos , Memória Imunológica , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais , Membro 14 de Receptores do Fator de Necrose Tumoral/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
16.
Blood ; 116(10): 1726-33, 2010 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-20519625

RESUMO

Natural killer (NK) cells are innate effector lymphocytes that control the growth of major histocompatibility complex class I negative tumors. We show here that γδ T lymphocytes, expanded in vitro in the presence isopentenylpyrophosphate (IPP), induce NK cell-mediated killing of tumors that are usually resistant to NK cytolysis. The induction of cytotoxicity toward these resistant tumors requires priming of NK cells by immobilized human immunoglobulin G1 and costimulation through CD137L expressed on activated γδ T lymphocytes. This costimulation increases NKG2D expression on the NK-cell surface, which is directly responsible for tumor cell lysis. Moreover, culturing peripheral blood mononuclear cells with zoledronic acid, a γδ T lymphocyte activating agent, enhances NK-cell direct cytotoxicity and antibody-dependent cellular cytotoxicity against hematopoietic and nonhematopoietic tumors. Our data reveal a novel function of human γδ T lymphocytes in the regulation of NK cell-mediated cytotoxicity and provide rationale for the use of strategies to manipulate the CD137 pathway to augment innate antitumor immunity.


Assuntos
Citotoxicidade Imunológica/imunologia , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Ligante 4-1BB/imunologia , Ligante 4-1BB/metabolismo , Antígeno B7-1/imunologia , Antígeno B7-1/metabolismo , Antígeno B7-2/imunologia , Antígeno B7-2/metabolismo , Comunicação Celular/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Cultura , Testes Imunológicos de Citotoxicidade , Citometria de Fluxo , Humanos , Imunoglobulina G/imunologia , Células K562 , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Ligante OX40/imunologia , Ligante OX40/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
17.
Blood ; 116(8): 1291-8, 2010 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-20472828

RESUMO

T-cell tolerance is the central program that prevents harmful immune responses against self-antigens, in which inhibitory PD-1 signal given by B7-H1 interaction plays an important role. Recent studies demonstrated that B7-H1 binds CD80 besides PD-1, and B7-H1/CD80 interaction also delivers inhibitory signals in T cells. However, a role of B7-H1/CD80 signals in regulation of T-cell tolerance has yet to be explored. We report here that attenuation of B7-H1/CD80 signals by treatment with anti-B7-H1 monoclonal antibody, which specifically blocks B7-H1/CD80 but not B7-H1/PD-1, enhanced T-cell expansion and prevented T-cell anergy induction. In addition, B7-H1/CD80 blockade restored Ag responsiveness in the previously anergized T cells. Experiments using B7-H1 or CD80-deficient T cells indicated that an inhibitory signal through CD80, but not B7-H1, on T cells is responsible in part for these effects. Consistently, CD80 expression was detected on anergic T cells and further up-regulated when they were re-exposed to the antigen (Ag). Finally, blockade of B7-H1/CD80 interaction prevented oral tolerance induction and restored T-cell responsiveness to Ag previously tolerized by oral administration. Taken together, our findings demonstrate that the B7-H1/CD80 pathway is a crucial regulator in the induction and maintenance of T-cell tolerance.


Assuntos
Autoantígenos/imunologia , Antígeno B7-1/fisiologia , Tolerância Imunológica/imunologia , Glicoproteínas de Membrana/fisiologia , Peptídeos/fisiologia , Linfócitos T/imunologia , Animais , Antígenos de Diferenciação/fisiologia , Antígeno B7-H1 , Western Blotting , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imunização , Imunoglobulina G/administração & dosagem , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Imunoprecipitação , Glicoproteínas de Membrana/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ovalbumina/metabolismo , Fragmentos de Peptídeos/imunologia , Peptídeos/antagonistas & inibidores , Receptor de Morte Celular Programada 1 , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos Lew , Receptores de Antígenos de Linfócitos T/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/citologia , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia
18.
J Immunol ; 184(2): 787-95, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20008291

RESUMO

CD137 (4-1BB)-mediated costimulation plays an important role in directing the fate of Ag-stimulated T cells and NK cells, yet the role of CD137 in mediating B cell function is unknown. We found that CD137 is expressed in vitro on anti-Ig-stimulated peripheral blood B cells and in vivo on tonsillar B cells with an activated phenotype. In vitro CD137 expression is enhanced by CD40 stimulation and IFN-gamma and is inhibited by IL-4, -10, and -21. The expression of CD137 on activated human B cells is functionally relevant because engagement with its ligand at the time of activation stimulates B cell proliferation, enhances B cell survival, and induces secretion of TNF-alpha and -beta. Our study suggests that CD137 costimulation may play a role in defining the fate of Ag-stimulated human B cells.


Assuntos
Linfócitos B/citologia , Proliferação de Células , Sobrevivência Celular , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/fisiologia , Antígenos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Sanguíneas , Antígenos CD40 , Humanos , Interleucinas , Ativação Linfocitária , Linfotoxina-alfa/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/agonistas , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/antagonistas & inibidores , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Fator de Necrose Tumoral alfa/metabolismo
19.
Nat Med ; 8(8): 793-800, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12091876

RESUMO

B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in the regulation of cellular and humoral immune responses through the PD-1 receptor on activated T and B cells. We report here that, except for cells of the macrophage lineage, normal human tissues do not express B7-H1. In contrast, B7-H1 is abundant in human carcinomas of lung, ovary and colon and in melanomas. The pro-inflammatory cytokine interferon-gamma upregulates B7-H1 on the surface of tumor cell lines. Cancer cell-associated B7-H1 increases apoptosis of antigen-specific human T-cell clones in vitro, and the apoptotic effect of B7-H1 is mediated largely by one or more receptors other than PD-1. In addition, expression of B7-H1 on mouse P815 tumor increases apoptosis of activated tumor-reactive T cells and promotes the growth of highly immunogenic B7-1(+) tumors in vivo. These findings have implications for the design of T cell-based cancer immunotherapy.


Assuntos
Apoptose , Antígeno B7-1/metabolismo , Proteínas Sanguíneas , Neoplasias/imunologia , Peptídeos , Linfócitos T Citotóxicos/fisiologia , Evasão Tumoral , Animais , Anticorpos Monoclonais , Antígenos CD , Antígenos de Superfície/metabolismo , Antineoplásicos/metabolismo , Proteínas Reguladoras de Apoptose , Antígeno B7-1/imunologia , Antígeno B7-H1 , Separação Celular , Proteína Ligante Fas , Feminino , Citometria de Fluxo , Humanos , Ativação Linfocitária , Melanoma/imunologia , Melanoma/metabolismo , Melanoma/patologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos , Neoplasias/metabolismo , Neoplasias/patologia , Receptor de Morte Celular Programada 1 , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Linfócitos T Citotóxicos/imunologia , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo
20.
Blood ; 112(3): 699-707, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18519814

RESUMO

CD137 (4-1BB) is a costimulatory molecule that can be manipulated for the treatment of cancer and autoimmune disease. Although it is known that agonistic antibodies (mAbs) against CD137 enhance the rejection of murine tumors in a natural killer (NK) cell- and T cell-dependent fashion, the mechanism for NK dependence is poorly understood. In this study, we evaluated the ability of 2 different glycoforms of a chimerized antihuman CD137 mAb, an aglycosylated (GA) and a low fucose form (GG), to react with human NK cells. Both mAbs bound similarly to CD137 and partially blocked the interaction between CD137 and CD137 ligand. However, unlike GA mAb, immobilized GG mAb activated NK cells and enhanced CD137 expression. These effects were seemingly dependent on Fc interaction with putative Fc receptors on the NK-cell surface, as only the immobilized Fc-fragment of GG was required for CD137 expression. Furthermore, CD137 expression could be enhanced with antibodies directed against non-CD137 epitopes, and the expression levels directly correlated with patterns of Fc-glycosylation recognized to improve Fc interaction with Fc gamma receptors. Our data suggest that CD137 can be enhanced on NK cells in an Fc-dependent fashion and that expression correlates with phenotypic and functional parameters of activation.


Assuntos
Anticorpos Monoclonais/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fragmentos Fc das Imunoglobulinas/fisiologia , Células Matadoras Naturais/metabolismo , Receptores Fc/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Células Cultivadas , Glicosilação , Humanos , Proteínas Recombinantes de Fusão
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