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1.
J Neuroinflammation ; 20(1): 100, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37122019

RESUMO

BACKGROUND: Tumour necrosis factor (TNF) is a pleiotropic cytokine and master regulator of the immune system. It acts through two receptors resulting in often opposing biological effects, which may explain the lack of therapeutic potential obtained so far in multiple sclerosis (MS) with non-receptor-specific anti-TNF therapeutics. Under neuroinflammatory conditions, such as MS, TNF receptor-1 (TNFR1) is believed to mediate the pro-inflammatory activities associated with TNF, whereas TNF receptor-2 (TNFR2) may instead induce anti-inflammatory effects as well as promote remyelination and neuroprotection. In this study, we have investigated the therapeutic potential of blocking TNFR1 whilst simultaneously stimulating TNFR2 in a mouse model of MS. METHODS: Experimental autoimmune encephalomyelitis (EAE) was induced with myelin oligodendrocyte glycoprotein (MOG35-55) in humanized TNFR1 knock-in mice. These were treated with a human-specific TNFR1-selective antagonistic antibody (H398) and a mouse-specific TNFR2 agonist (EHD2-sc-mTNFR2), both in combination and individually. Histopathological analysis of spinal cords was performed to investigate demyelination and inflammatory infiltration, as well as axonal and neuronal degeneration. Retinas were examined for any protective effects on retinal ganglion cell (RGC) degeneration and neuroprotective signalling pathways analysed by Western blotting. RESULTS: TNFR modulation successfully ameliorated symptoms of EAE and reduced demyelination, inflammatory infiltration and axonal degeneration. Furthermore, the combinatorial approach of blocking TNFR1 and stimulating TNFR2 signalling increased RGC survival and promoted the phosphorylation of Akt and NF-κB, both known to mediate neuroprotection. CONCLUSION: These results further support the potential of regulating the balance of TNFR signalling, through the co-modulation of TNFR1 and TNFR2 activity, as a novel therapeutic approach in treating inflammatory demyelinating disease.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Humanos , Animais , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Inibidores do Fator de Necrose Tumoral , Encefalomielite Autoimune Experimental/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Anticorpos/uso terapêutico
2.
Psychol Res ; 87(4): 1101-1113, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36107250

RESUMO

In a repetition-change paradigm it was explored whether the skin conductance response (SCR) and the heart rate (HR) response similarly reflect involuntary and voluntary orienting. Seven orienting stimuli, consisting of six contextually novel stimuli and one novel change, were presented to 144 participants. In order to evoke voluntary orienting, the signal value of the contextually novel stimuli was manipulated by task instruction. Results suggest that the SCR is a manifestation of the involuntary orienting response (iOR). The HR, however, showed a non-uniform pattern of response and turned out to be susceptible to voluntary orienting. While it responded to the last orienting stimulus, the novel change, with a clear-cut deceleration, the response to the first orienting stimulus had a polyphase structure and was sensitive to repetition and signal value. The HR response is, thus, of limited value as an indicator of the iOR because of its striking susceptibility to voluntary orienting.


Assuntos
Resposta Galvânica da Pele , Orientação , Humanos , Orientação/fisiologia , Frequência Cardíaca/fisiologia
3.
Hum Brain Mapp ; 42(5): 1227-1242, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33325575

RESUMO

An accruing body of research has shown that interoception (the sensing of signals from the body's internal milieu) relies on both a direct route (afforded by the vagus nerve) and a secondary route (supported by somatosensory mechanisms). However, no study has causally tested the differential role of these pathways, let alone via direct stimulation. To bridge this gap, we tested whether multidimensional signatures of interoception are modulated by noninvasive vagus nerve stimulation (nVNS). Sixty-three participants were divided into an nVNS and a sham-stimulation group. Before and after stimulation, both groups performed a validated heartbeat detection (HBD) task including a genuinely interoceptive condition (monitoring one's own heartbeat) and a control exteroceptive condition (tracking an aurally presented heartbeat). Electroencephalographic signals were obtained during both conditions to examine modulations of the heartbeat-evoked potential (HEP). Moreover, before and after stimulation, participants were asked to complete a somatosensory heartbeat localization task. Results from the interoceptive condition revealed that, after treatment, only the nVNS group exhibited improved performance and greater HEP modulations. No behavioral differences were found for the exteroceptive control condition, which was nonetheless associated with significant HEP modulations. Finally, no between-group differences were observed regarding the localization of the heartbeat sensations or relevant cardiodynamic variables (heart rate and or heart rate variability). Taken together, these results constitute unprecedented evidence that the vagus nerve plays a direct role in neurovisceral integration during interoception. This finding can constrain mechanistic models of the domain while informing a promising transdiagnostic agenda for interoceptive impairments across neuropsychiatric conditions.


Assuntos
Eletroencefalografia , Potenciais Evocados/fisiologia , Frequência Cardíaca/fisiologia , Interocepção/fisiologia , Estimulação do Nervo Vago , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Adulto Jovem
4.
Hum Brain Mapp ; 41(2): 401-418, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31609042

RESUMO

Exteroceptive and interoceptive signals shape and sustain the bodily self-awareness. The existence of a set of brain areas, supporting the integration of information coming from the inside and the outside of the body in building the sense of bodily self-awareness has been postulated, yet the evidence remains limited, a matter of discussion never assessed quantitatively. With the aim of unrevealing where in the brain interoceptive and exteroceptive signals may converge, we performed a meta-analysis on imaging studies of the sense of body ownership, modulated by external visuotactile stimulation, and studies on interoception, which involves the self-awareness for internal bodily sensations. Using a multilevel kernel density analysis, we found that processing of stimuli of the two domains converges primarily in the supramarginal gyrus bilaterally. Furthermore, we found a right-lateralized set of areas, including the precentral and postcentral, and superior temporal gyri. We discuss these results and propose this set of areas as ideal candidates to match multiple body-related signals contributing to the creation of a multidimensional representation of the bodily self.


Assuntos
Conscientização/fisiologia , Córtex Cerebral/fisiologia , Neuroimagem Funcional , Interocepção/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Humanos , Análise Multinível , Estimulação Física
5.
Mult Scler ; 26(14): 1845-1853, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31778101

RESUMO

BACKGROUND: Fatigue ranks among the most common and disabling symptoms in multiple sclerosis (MS). Recent theoretical works have surmised that this trait might be related to alterations across interoceptive mechanisms. However, this hypothesis has not been empirically evaluated. OBJECTIVES: To determine whether fatigue in MS patients is associated with specific behavioral, structural, and functional disruptions of the interoceptive domain. METHODS: Fatigue levels were established via the Modified Fatigue Impact Scale. Interoception was evaluated through a robust measure indexed by the heartbeat detection task. Structural and functional connectivity properties of key interoceptive hubs were tested by magnetic resonance imaging (MRI) and resting-state functional MRI. Machine learning analyses were employed to perform pairwise classifications. RESULTS: Only patients with fatigue presented with decreased interoceptive accuracy alongside decreased gray matter volume and increased functional connectivity in core interoceptive regions, the insula, and the anterior cingulate cortex. Each of these alterations was positively associated with fatigue. Finally, machine-learning analysis with a combination of the above interoceptive indices (behavioral, structural, and functional) successfully discriminated (area under the curve > 90%) fatigued patients from both non-fatigued and healthy controls. CONCLUSION: This study offers unprecedented evidence suggesting that disruptions of neurocognitive markers subserving interoception may constitute a signature of fatigue in MS.


Assuntos
Interocepção , Esclerose Múltipla , Córtex Cerebral/diagnóstico por imagem , Fadiga/etiologia , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla/complicações
6.
J Biol Chem ; 287(7): 4462-9, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22147690

RESUMO

Many therapeutic proteins possessing a small size are rapidly cleared from circulation. Half-life extension strategies have therefore become increasingly important to improve the pharmacokinetic and pharmacodynamic properties of protein therapeutics. Here, we performed a comparative analysis of the half-life extension properties of various bacterial immunoglobulin-binding domains (IgBDs) derived from Staphylococcus protein A (SpA), Streptococcus protein G (SpG), and Finegoldia (formerly Peptostreptococcus) protein L (PpL). These domains, composed of 50-60 amino acid residues, were fused to the C terminus of a single-chain Fv and a bispecific single-chain diabody, respectively. All fusion proteins were produced in mammalian cells and retained their antigen-binding properties. The half-lives of the antibody molecules were prolonged to varying extents for the different IgBDs. The strongest effects in mice were observed for domain C3 of SpG (SpG(C3)) followed by domains B and D of SpA, suggesting that SpG(C3) is particularly useful to extend the plasma half-life of small proteins.


Assuntos
Proteínas de Bactérias/farmacocinética , Proteínas Recombinantes de Fusão/farmacocinética , Anticorpos de Cadeia Única/farmacocinética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Meia-Vida , Humanos , Células Jurkat , Camundongos , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/farmacologia
7.
Cell Stress ; 7(11): 95-104, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37970489

RESUMO

Adoptive cell therapy (ACT) can successfully treat hematopoietic cancers but lacks efficacy against solid tumors. This is due to insufficient T cell infiltration, high tumor heterogeneity, frequent antigen loss with subsequent tumor escape, and the immunosuppressive tumor microenvironment (TME). Alternative methods to boost the anticancer efficacy of adoptively transferred cells are actively pursued. Among adjuvants that are utilized to stimulate anticancer immune responses, ligands of the stimulator of interferon genes (STING) pathway have received increasing attention. STING activation can trigger dendritic cell (DC) activation and endogenous immune responses, thereby preventing tumor escape. Activation of the STING pathway in the context of ACT was accordingly associated with improved T cell trafficking and persistence in the TME combined with the reduced presence of immunosuppressive cells. Recent findings also suggest cell-intrinsic effects of STING ligands on T cells. Activation of the STING signaling pathway was in this regard shown to enhance effector functions of CD4+ and CD8+ T cells, suggesting that the STING signaling could be exploited to harness T cell anticancer functions. In this review, we will discuss how the STING signaling can be used to enhance the anticancer efficacy of ACT.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37923150

RESUMO

BACKGROUND: Disturbance in bodily experience (BE) is a potential adverse consequence of ventricular assist device (VAD) implantation. The concept BE encompasses all cognitive and affective processes related to the subjective experience of one's own body. METHODS: A cross-sectional, multicenter study was performed, involving 365 VAD patients (85% male; time postimplant: 3-36 months). Patients completed a BE questionnaire (BE-S, 5-point Likert scale), and the disturbance in BE was analyzed based on sex, time since implantation (in the first, second, or third years postimplant), and patient acuity (elective vs emergent implantation). Subsidiary, patients' gratitude was surveyed. RESULTS: Disturbance in BE was not particularly pronounced (mean = 2.69, standard deviation = 1.17). Eighty-five percent of patients expressed high levels of gratitude. Disturbance in BE decreased (p = 0.04), while gratitude increased (p = 0.02) with time since implantation. Female patients showed more disturbance in BE (p = 0.01) and less gratitude (p = 0.01) compared to male patients. Among patients who underwent emergency implantation, the decrease in disturbance occurred predominantly in the third year, exceeding the level observed in elective implanted patients (p = 0.03). CONCLUSIONS: Disturbance in BE following VAD implantation does generally not reach excessive levels and tends to decrease over time. Our data indicate more disturbance and less gratitude in female patients. In emergently implanted patients, disturbance in BE is prolonged. Screening for disturbance in BE is recommended during follow-up, especially for these at-risk groups, to ensure early and focused psychological support.

9.
Cancer Immunol Res ; 11(7): 925-945, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37172100

RESUMO

IMA101 is an actively personalized, multi-targeted adoptive cell therapy (ACT), whereby autologous T cells are directed against multiple novel defined peptide-HLA (pHLA) cancer targets. HLA-A*02:01-positive patients with relapsed/refractory solid tumors expressing ≥1 of 8 predefined targets underwent leukapheresis. Endogenous T cells specific for up to 4 targets were primed and expanded in vitro. Patients received lymphodepletion (fludarabine, cyclophosphamide), followed by T-cell infusion and low-dose IL2 (Cohort 1). Patients in Cohort 2 received atezolizumab for up to 1 year (NCT02876510). Overall, 214 patients were screened, 15 received lymphodepletion (13 women, 2 men; median age, 44 years), and 14 were treated with T-cell products. IMA101 treatment was feasible and well tolerated. The most common adverse events were cytokine release syndrome (Grade 1, n = 6; Grade 2, n = 4) and expected cytopenias. No patient died during the first 100 days after T-cell therapy. No neurotoxicity was observed. No objective responses were noted. Prolonged disease stabilization was noted in three patients lasting for 13.7, 12.9, and 7.3 months. High frequencies of target-specific T cells (up to 78.7% of CD8+ cells) were detected in the blood of treated patients, persisted for >1 year, and were detectable in posttreatment tumor tissue. Individual T-cell receptors (TCR) contained in T-cell products exhibited broad variation in TCR avidity, with the majority being low avidity. High-avidity TCRs were identified in some patients' products. This study demonstrates the feasibility and tolerability of an actively personalized ACT directed to multiple defined pHLA cancer targets. Results warrant further evaluation of multi-target ACT approaches using potent high-avidity TCRs. See related Spotlight by Uslu and June, p. 865.


Assuntos
Imunoterapia Adotiva , Neoplasias , Adulto , Feminino , Humanos , Masculino , Linfócitos T CD8-Positivos , Estudos de Viabilidade , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Neoplasias/terapia , Neoplasias/etiologia , Receptores de Antígenos de Linfócitos T/genética
10.
Biol Psychol ; 159: 108017, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450326

RESUMO

Theoretical approaches propose a blending between interoception and time estimation. Interoception might constitute a neurophysiological mechanism for encoding duration. However, no study has assessed the convergence between interoception and time estimation using behavioral, neurophysiological, and functional anatomy signatures. We examined the multimodal convergence between interoception and time estimation using a two-fold approach. In study 1, we developed a dual design combining interoception (measuring heartbeat detection - HBD, and heartbeat evoked potential - HEP) with a time estimation paradigm (TEP, estimation of duration of a 120 s interval). In study 2, we performed a conjoint metanalysis (Multi-level Kernel Density Analysis, MKDA) of neuroimaging, including reports of interoception and time estimation. Both studies provide convergent evidence of time estimation's significant involvement in behavioral, electrophysiological (enhanced HEP), and neuroimaging (overlapping cluster in the right insula and operculum) signatures of interoception. Convergent results from both studies offer direct support for a shared mechanism of interoception and time estimation.


Assuntos
Interocepção , Córtex Cerebral/diagnóstico por imagem , Potenciais Evocados , Frequência Cardíaca , Humanos , Neuroimagem
11.
Blood Adv ; 5(23): 5349-5359, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34592754

RESUMO

Chronic nonresolving inflammatory syndrome is a major disease feature in myeloproliferative neoplasms (MPNs). Systemic inflammation promotes the growth of the JAK2-V617F+ hematopoietic stem cell clone and is associated with constitutive symptoms (eg, fever, cachexia, and fatigue). Therefore, it is being discussed whether anti-inflammatory therapy, in addition to the well-established JAK inhibitor therapy, may be beneficial in the control of constitutive symptoms. Moreover, effective control of the inflammatory microenvironment may contribute to prevent transformation into secondary myelofibrosis and acute leukemia. Given the pivotal role of tumor necrosis factor α (TNF-α) in MPN and the distinct roles of TNF-α receptor 1 (TNFR1) and TNFR2 in inflammation, we investigated the therapeutic effects of αTNFR1 and αTNFR2 antibody treatment in MPN-like disease using the JAK2+/VF knock-in mouse model. Peripheral blood counts, bone marrow/spleen histopathology, and inflammatory cytokine levels in serum were investigated. αTNFR2 antibody treatment decreased white blood cells and modulated the serum levels of several cytokines [CXCL2, CXCL5, interleukin-12(p40)], as well as of macrophage colony-stimulating factor, but they lacked efficacy to ameliorate hematocrit and splenomegaly. αTNFR1 antibody treatment resulted in the mild suppression of elevated hematocrit of -10.7% and attenuated splenomegaly (22% reduction in spleen weight). In conclusion, our studies show that TNFR1 and TNFR2 play different roles in the biology of JAK2-V617F-induced disease that may be of relevance in future therapeutic settings.


Assuntos
Transtornos Mieloproliferativos , Mielofibrose Primária , Animais , Anti-Inflamatórios , Camundongos , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Mielofibrose Primária/tratamento farmacológico , Mielofibrose Primária/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/genética
12.
Front Allergy ; 2: 680937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35386993

RESUMO

Seasonal exposure to birch pollen (BP) is a major cause of pollinosis. The specific role of Toll-like receptor 4 (TLR4) in BP-induced allergic inflammation and the identification of key factors in birch pollen extracts (BPE) initiating this process remain to be explored. This study aimed to examine (i) the importance of TLR4 for dendritic cell (DC) activation by BPE, (ii) the extent of the contribution of BPE-derived lipopolysaccharide (LPS) and other potential TLR4 adjuvant(s) in BPE, and (iii) the relevance of the TLR4-dependent activation of BPE-stimulated DCs in the initiation of an adaptive immune response. In vitro, activation of murine bone marrow-derived DCs (BMDCs) and human monocyte-derived DCs by BPE or the equivalent LPS (nLPS) was analyzed by flow cytometry. Polymyxin B (PMB), a TLR4 antagonist and TLR4-deficient BMDCs were used to investigate the TLR4 signaling in DC activation. The immunostimulatory activity of BPE was compared to protein-/lipid-depleted BPE-fractions. In co-cultures of BPE-pulsed BMDCs and Bet v 1-specific hybridoma T cells, the influence of the TLR4-dependent DC activation on T cell activation was analyzed. In vivo immunization of IL-4 reporter mice was conducted to study BPE-induced Th2 polarization upon PMB pre-treatment. Murine and human DC activation induced by either BPE or nLPS was inhibited by the TLR4 antagonist or by PMB, and abrogated in TLR4-deficient BMDCs compared to wild-type BMDCs. The lipid-free but not the protein-free fraction showed a reduced capacity to activate the TLR4 signaling and murine DCs. In human DCs, nLPS only partially reproduced the BPE-induced activation intensity. BPE-primed BMDCs efficiently stimulated T cell activation, which was repressed by the TLR4 antagonist or PMB, and the addition of nLPS to Bet v 1 did not reproduce the effect of BPE. In vivo, immunization with BPE induced a significant Th2 polarization, whereas administration of BPE pre-incubated with PMB showed a decreased tendency. These findings suggest that TLR4 is a major pathway by which BPE triggers DC activation that is involved in the initiation of adaptive immune responses. Further characterization of these BP-derived TLR4 adjuvants could provide new candidates for therapeutic strategies targeting specific mechanisms in BP-induced allergic inflammation.

13.
Front Immunol ; 12: 705485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305946

RESUMO

Therapeutics that block tumor necrosis factor (TNF), and thus activation of TNF receptor 1 (TNFR1) and TNFR2, are clinically used to treat inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease and psoriasis. However, TNFR1 and TNFR2 work antithetically to balance immune responses involved in inflammatory diseases. In particular, TNFR1 promotes inflammation and tissue degeneration, whereas TNFR2 contributes to immune modulation and tissue regeneration. We, therefore, have developed the monovalent antagonistic anti-TNFR1 antibody derivative Atrosimab to selectively block TNFR1 signaling, while leaving TNFR2 signaling unaffected. Here, we describe that Atrosimab is highly stable at different storage temperatures and demonstrate its therapeutic efficacy in mouse models of acute and chronic inflammation, including experimental arthritis, non-alcoholic steatohepatitis (NASH) and experimental autoimmune encephalomyelitis (EAE). Our data support the hypothesis that it is sufficient to block TNFR1 signaling, while leaving immune modulatory and regenerative responses via TNFR2 intact, to induce therapeutic effects. Collectively, we demonstrate the therapeutic potential of the human TNFR1 antagonist Atrosimab for treatment of chronic inflammatory diseases.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Fatores Imunológicos/farmacologia , Receptores Tipo I de Fatores de Necrose Tumoral/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
14.
Mol Cancer Ther ; 19(7): 1474-1485, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32430487

RESUMO

The frequent activation of HER3 signaling as a resistance mechanism to EGFR-targeted therapy has motivated the development of combination therapies that block more than one receptor tyrosine kinase. Here, we have developed a novel tetravalent, bispecific single-chain diabody-Fc fusion protein targeting EGFR and HER3 (also known as ErbB3) that integrates the antigen-binding sites of a humanized version of cetuximab as well as a recently developed anti-HER3 antibody, IgG 3-43. This bispecific antibody combines the binding and neutralizing properties of the parental antibodies, as observed in biochemical and in vitro two-dimensional and three-dimensional cell culture assays, and gave rise to long-lasting growth suppression in a subcutaneous xenograft head and neck tumor model. In triple-negative breast cancer (TNBC) cell lines, treatment with the bispecific antibody inhibited the proliferation and oncosphere formation efficiency driven by HER3 signaling. In an orthotopic MDA-MB-468 tumor model, this translated into antitumor effects superior to those obtained by the parental antibodies alone or in combination and was associated with a reduced number of cells with stem-like properties. These findings demonstrate that the bispecific antibody efficiently blocks not only TNBC proliferation, but also the survival and expansion of the cancer stem cell population, holding promise for further preclinical development.


Assuntos
Anticorpos Biespecíficos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Receptor ErbB-3/antagonistas & inibidores , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Feminino , Humanos , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptor ErbB-3/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
MAbs ; 11(5): 919-929, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30951400

RESUMO

Multivalent mono- or bispecific antibodies are of increasing interest for therapeutic applications, such as efficient receptor clustering and activation, or dual targeting approaches. Here, we present a novel platform for the generation of Ig-like molecules, designated diabody-Ig (Db-Ig). The antigen-binding site of Db-Ig is composed of a diabody in the VH-VL orientation stabilized by fusion to antibody-derived homo- or heterodimerization domains, e.g., CH1/CL or the heavy chain domain 2 of IgE (EHD2) or IgM (MHD2), further fused to an Fc region. In this study, we applied the Db-Ig format for the generation of tetravalent bispecific antibodies (2 + 2) directed against EGFR and HER3 and utilizing different dimerization domains. These Db-Ig antibodies retained the binding properties of the parental antibodies and demonstrated unhindered simultaneous binding of both antigens. The Db-Ig antibodies could be purified by a single affinity chromatography resulting in a homogenous preparation. Furthermore, the Db-Igs were highly stable in human plasma. Importantly, only one short peptide linker (5 aa) per chain is required to generate a Db-Ig molecule, reducing the potential risk of immunogenicity. The presence of a fully functional Fc resulted in IgG-like pharmacokinetic profiles of the Db-Ig molecules. Besides tetravalent bispecific molecules, this modular platform technology further allows for the generation of other multivalent molecules of varying specificity and valency, including mono-, bi-, tri- and tetra-specific molecules, and thus should be suitable for numerous applications.


Assuntos
Anticorpos Biespecíficos/imunologia , Dimerização , Anticorpos Biespecíficos/metabolismo , Anticorpos Biespecíficos/farmacocinética , Apoptose/imunologia , Receptores ErbB/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Receptor ErbB-3/imunologia
16.
MAbs ; 11(4): 653-665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30929560

RESUMO

The development of alternative therapeutic strategies to tumor necrosis factor (TNF)-blocking antibodies for the treatment of inflammatory diseases has generated increasing interest. In particular, selective inhibition of TNF receptor 1 (TNFR1) promises a more precise intervention, tackling only the pro-inflammatory responses mediated by TNF while leaving regenerative and pro-survival signals transduced by TNFR2 untouched. We recently generated a monovalent anti-TNFR1 antibody fragment (Fab 13.7) as an efficient inhibitor of TNFR1. To improve the pharmacokinetic properties of Fab 13.7, the variable domains of the heavy and light chains were fused to the N-termini of newly generated heterodimerizing Fc chains. This novel Fc heterodimerization technology, designated "Fc-one/kappa" (Fc1κ) is based on interspersed constant Ig domains substituting the CH3 domains of a γ1 Fc. The interspersed immunoglobulin (Ig) domains originate from the per se heterodimerizing constant CH1 and CLκ domains and contain sequence stretches of an IgG1 CH3 domain, destined to enable interaction with the neonatal Fc receptor, and thus promote extended serum half-life. The resulting monovalent Fv-Fc1κ fusion protein (Atrosimab) retained strong binding to TNFR1 as determined by enzyme-linked immunosorbent assay and quartz crystal microbalance, and potently inhibited TNF-induced activation of TNFR1. Atrosimab lacks agonistic activity for TNFR1 on its own and in the presence of anti-human IgG antibodies and displays clearly improved pharmacokinetic properties.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Neutralizantes/genética , Fragmentos Fc das Imunoglobulinas/genética , Imunoterapia/métodos , Inflamação/terapia , Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/metabolismo , Dimerização , Ensaio de Imunoadsorção Enzimática , Humanos , Inflamação/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Proteínas Recombinantes de Fusão/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores
17.
MAbs ; 11(1): 166-177, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252601

RESUMO

Selective inhibition of tumor necrosis factor (TNF) signaling through the proinflammatory axis of TNF-receptor 1 (TNFR1) while leaving pro-survival and regeneration-promoting signals via TNFR2 unaffected is a promising strategy to circumvent limitations of complete inhibition of TNF action by the approved anti-TNF drugs. A previously developed humanized antagonistic TNFR1-specific antibody, ATROSAB, showed potent inhibition of TNFR1-mediated cellular responses. Because the parental mouse antibody H398 possesses even stronger inhibitory potential, we scrutinized the specific binding parameters of the two molecules and revealed a faster dissociation of ATROSAB compared to H398. Applying affinity maturation and re-engineering of humanized variable domains, we generated a monovalent Fab derivative (13.7) of ATROSAB that exhibited increased binding to TNFR1 and superior inhibition of TNF-mediated TNFR1 activation, while lacking any agonistic activity even in the presence of cross-linking antibodies. In order to improve its pharmacokinetic properties, several Fab13.7-derived molecules were generated, including a PEGylated Fab, a mouse serum albumin fusion protein, a half-IgG with a dimerization-deficient Fc, and a newly designed Fv-Fc format, employing the knobs-into-holes technology. Among these derivatives, the Fv13.7-Fc displayed the best combination of improved pharmacokinetic properties and antagonistic activity, thus representing a promising candidate for further clinical development.


Assuntos
Anticorpos Monoclonais/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/antagonistas & inibidores , Anticorpos de Cadeia Única/imunologia , Animais , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/imunologia , Afinidade de Anticorpos , Humanos , Camundongos , Engenharia de Proteínas/métodos
18.
Cortex ; 88: 124-142, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28088652

RESUMO

Guided by indirect evidence, recent approaches propose a tripartite crosstalk among interoceptive signaling, emotional regulation, and low-level social cognition. Here we examined the neurocognitive convergence of such domains. First, we performed three meta-analyses of functional magnetic resonance imaging studies to identify which areas are consistently coactivated by these three systems. Multi-level Kernel Density Analysis (MKDA) revealed major overlaps in the right anterior insular and frontotemporal regions (viz., the orbitofrontal and inferior frontal gyri, the amygdala, and mid temporal lobe/subcortical structures). Second, we explored such domains in patients with fronto-insulo-temporal damage. Relative to controls, the patients showed behavioral impairments of interoception, emotional processing, and social cognition, with preservation of other cognitive functions. Convergent results from both studies offer direct support for a model of insular-frontotemporal regions integrating interoception, emotion, and social cognition.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Interocepção/fisiologia , Percepção Social , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
19.
MAbs ; 8(1): 120-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26514880

RESUMO

Fusion to an IgG Fc region is an established strategy to extend the half-life of therapeutic proteins. Most Fc fusion proteins, however, do not achieve the long half-life of IgGs. Based on findings that scFv-Fc fusion proteins exhibit a shorter half-life than the corresponding IgG molecules, we performed a comparative study of different antibody-derived Fc fusion proteins. We could confirm that fusion of single-chain Fv (scFv) and single-chain diabody (scDb) molecules to an Fc region yields in fusion proteins with substantially extended half-lives compared with the single-chain versions. However, even fusion proteins with a size similar to that of IgG, e.g., scDb-Fc, did not have a half-life as long as an IgG molecule. Binding to the neonatal Fc receptor (FcRn) under acidic and neutral conditions was similar for IgG and all Fc fusion proteins. However, we observed differences between IgG and the Fc fusion proteins for dissociation of FcRn-bound proteins induced by shifting from acidic to neutral pH, reflecting the physiological release mechanism, further supporting a contribution of the kinetics of pH-dependent release from FcRn to the pharmacokinetic properties of IgG and Fc fusion proteins.


Assuntos
Fragmentos Fc das Imunoglobulinas/farmacologia , Imunoglobulina G/farmacologia , Proteínas Recombinantes de Fusão , Animais , Células CHO , Cricetinae , Cricetulus , Feminino , Células HEK293 , Humanos , Camundongos , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia
20.
PLoS One ; 11(10): e0163314, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27755542

RESUMO

Chronic inflammatory conditions during peritoneal dialysis (PD)-treatment lead to the impairment of peritoneal tissue integrity. The resulting structural and functional reorganization of the peritoneal membrane diminishes ultrafiltration rate and thereby enhances mortality by limiting dialysis effectiveness over time. Tumour necrosis factor (TNF) and its receptors TNFR1 and TNFR2 are key players during inflammatory processes. To date, the role of TNFR1 in peritoneal tissue damage during PD-treatment is completely undefined. In this study, we used an acute PD-mouse model to investigate the role of TNFR1 on structural and morphological changes of the peritoneal membrane. TNFR1-mediated TNF signalling in transgenic mice expressing human TNFR1 was specifically blocked by applying a monoclonal antibody (H398) highly selective for human TNFR1 prior to PD-treatment. Cancer antigen-125 (CA125) plasma concentrations were measured by enzyme-linked immunosorbent assay (ELISA). Western blot analyses were applied to determine TNFR2 protein concentrations. Histological staining of peritoneal tissue sections was performed to assess granulocytes within the peritoneal membrane as well as the content of hyaluronic acid and collagen. We show for the first time that the number of granulocytes within the peritoneal membrane is significantly reduced in mice pre-treated with H398. Moreover, we demonstrate that blocking of TNFR1 not only influences CA125 values but also hyaluronic acid and collagen contents of the peritoneal tissue in these mice. These results strongly suggest that TNFR1 inhibition attenuates peritoneal damage caused by peritoneal dialysis fluid (PDF) and therefore may represent a new therapeutic approach in the treatment of PD-related side effects.


Assuntos
Inflamação/prevenção & controle , Peritônio/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Animais , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/imunologia , Antígeno Ca-125/sangue , Colágeno/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Granulócitos/citologia , Granulócitos/metabolismo , Ácido Hialurônico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Diálise Peritoneal , Peritônio/patologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo
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