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1.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361793

RESUMO

The pretargeting strategy has recently emerged in order to overcome the limitations of direct targeting, mainly in the field of radioimmunotherapy (RIT). This strategy is directly dependent on chemical reactions, namely bioorthogonal reactions, which have been developed for their ability to occur under physiological conditions. The Staudinger ligation, the copper catalyzed azide-alkyne cycloaddition (CuAAC) and the strain-promoted [3 + 2] azide-alkyne cycloaddition (SPAAC) were the first bioorthogonal reactions introduced in the literature. However, due to their incomplete biocompatibility and slow kinetics, the inverse-electron demand Diels-Alder (IEDDA) reaction was advanced in 2008 by Blackman et al. as an optimal bioorthogonal reaction. The IEDDA is the fastest bioorthogonal reaction known so far. Its biocompatibility and ideal kinetics are very appealing for pretargeting applications. The use of a trans-cyclooctene (TCO) and a tetrazine (Tz) in the reaction encouraged researchers to study them deeply. It was found that both reagents are sensitive to acidic or basic conditions. Furthermore, TCO is photosensitive and can be isomerized to its cis-conformation via a radical catalyzed reaction. Unfortunately, the cis-conformer is significantly less reactive toward tetrazine than the trans-conformation. Therefore, extensive research has been carried out to optimize both click reagents and to employ the IEDDA bioorthogonal reaction in biomedical applications.


Assuntos
Antineoplásicos/química , Química Click/métodos , Terapia de Alvo Molecular/métodos , Neoplasias/terapia , Radiossensibilizantes/química , Radioimunoterapia/métodos , Alcinos/química , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Azidas/química , Reação de Cicloadição/métodos , Ciclo-Octanos/química , Elétrons , Compostos Heterocíclicos com 1 Anel/química , Humanos , Concentração de Íons de Hidrogênio , Imunoconjugados/química , Imunoconjugados/farmacocinética , Imunoconjugados/farmacologia , Neoplasias/química , Neoplasias/imunologia , Neoplasias/patologia , Fotoquimioterapia/métodos , Radiossensibilizantes/farmacocinética , Radiossensibilizantes/farmacologia
2.
Theranostics ; 11(16): 7700-7714, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335959

RESUMO

CD4+ T helper cells are capable of mediating long-term antitumoral immune responses. We developed a combined immunotherapy (COMBO) using tumor antigen-specific T helper 1 cells (Tag-Th1), dual PD-L1/LAG-3 immune checkpoint blockade, and a low-dose total body irradiation (TBI) of 2 Gy, that was highly efficient in controlling the tumor burden of non-immunogenic RIP1-Tag2 mice with late-stage endogenous pancreatic islet carcinomas. In this study, we aimed to explore the impact of 2 Gy TBI on the treatment efficacy and the underlying mechanisms to boost CD4+ T cell-based immunotherapies. Methods: Heavily progressed RIP1-Tag2 mice underwent COMBO treatment and their survival was compared to a cohort without 2 Gy TBI. Positron emission tomography/computed tomography (PET/CT) with radiolabeled anti-CD3 monoclonal antibodies and flow cytometry were applied to investigate 2 Gy TBI-induced alterations in the biodistribution of endogenous T cells of healthy C3H mice. Migration and homing properties of Cy5-labeled adoptive Tag-Th1 cells were monitored by optical imaging and flow cytometric analyses in C3H and tumor-bearing RIP1-Tag2 mice. Splenectomy or sham-surgery of late-stage RIP1-Tag2 mice was performed before onset of COMBO treatment to elucidate the impact of the spleen on the therapy response. Results: First, we determined a significant longer survival of RIP1-Tag2 mice and an increased CD4+ T cell tumor infiltrate when 2 Gy TBI was applied in addition to Tag-Th1 cell PD-L1/LAG-3 treatment. In non-tumor-bearing C3H mice, TBI induced a moderate host lymphodepletion and a tumor antigen-independent accumulation of Tag-Th1 cells in lymphoid and non-lymphoid organs. In RIP1-Tag2, we found increased numbers of effector memory-like Tag-Th1 and endogenous CD4+ T cells in the pancreatic tumor tissue after TBI, accompanied by a tumor-specific Th1-driven immune response. Furthermore, the spleen negatively regulated T cell effector function by upregulation PD-1/LAG-3/TIM-3 immune checkpoints, providing a further rationale for this combined treatment approach. Conclusion: Low-dose TBI represents a powerful tool to foster CD4+ T cell-based cancer immunotherapies by favoring Th1-driven antitumoral immunity. As TBI is a clinically approved and well-established technique it might be an ideal addition for adoptive cell therapy with CD4+ T cells in the clinical setting.


Assuntos
Imunoterapia/métodos , Células Th1/metabolismo , Irradiação Corporal Total/métodos , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Neoplasias , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Feminino , Imunidade/efeitos dos fármacos , Imunoterapia Adotiva/métodos , Camundongos , Camundongos Endogâmicos C3H , Imagem Óptica , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Células Th1/imunologia , Distribuição Tecidual
3.
Emerg Microbes Infect ; 10(1): 1638-1648, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34346827

RESUMO

MW33 is a fully humanized IgG1κ monoclonal neutralizing antibody, and may be used for the prevention and treatment of coronavirus disease 2019 (COVID-19). We conducted a randomized, double-blind, placebo-controlled, single-dose, dose-escalation Phase 1 study to evaluate the safety, tolerability, pharmacokinetics (PK), and immunogenicity of MW33. Healthy adults aged 18-45 years were sequentially enrolled into the 4, 10, 20, 40, and 60 mg/kg dose groups and infused with MW33 over 60 ± 15 min and followed for 85 days. All 42 enrolled participants completed the MW33 infusion, and 40 participants completed the 85-day follow-up period. 34 participants received a single infusion of 4 (n = 2), 10 (n = 8), 20 (n = 8), 40 (n = 8), and 60 mg/kg (n = 8) of MW33. 27 subjects in the test groups experienced 78 adverse events (AEs) post-dose, with an incidence of 79.4% (27/34). The most common AEs included abnormal laboratory test results, vascular and lymphatic disorders, and infectious diseases. The severity of AEs was mainly Grade 1 (92 AEs), and three Grade 2 and one Grade 4. The main PK parameters, maximum concentration (Cmax), and area under the concentration-time curve (AUC0-t, and AUC0-∞) in 34 subjects showed a linear kinetic relationship in the range of 10-60 mg/kg. The plasma half-life was approximately 25 days. The positive rates of serum ADAs and antibody titres were low with no evidence of an impact on safety or PK. In conclusion, MW33 was well-tolerated, demonstrated linear PK, with a lower positive rate of serum ADAs and antibody titres in healthy subjects.Trial registration: ClinicalTrials.gov identifier: NCT04427501.Trial registration: ClinicalTrials.gov identifier: NCT04533048.Trial registration: ClinicalTrials.gov identifier: NCT04627584.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , Adulto , COVID-19/diagnóstico , COVID-19/imunologia , Análise de Dados , Feminino , Humanos , Masculino , SARS-CoV-2/imunologia , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
4.
Cell Rep ; 36(4): 109450, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34289384

RESUMO

Improving clinical care for individuals infected with SARS-CoV-2 variants is a global health priority. Small-molecule antivirals like remdesivir (RDV) and biologics such as human monoclonal antibodies (mAbs) have demonstrated therapeutic efficacy against SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19). It is not known whether combination RDV/mAb will improve outcomes over single-agent therapies or whether antibody therapies will remain efficacious against variants. Here, we show that a combination of two mAbs in clinical trials, C144 and C135, have potent antiviral effects against even when initiated 48 h after infection and have therapeutic efficacy in vivo against the B.1.351 variant of concern (VOC). Combining RDV and antibodies provided a modest improvement in outcomes compared with single agents. These data support the continued use of RDV to treat SARS-CoV-2 infections and the continued clinical development of the C144 and C135 antibody combination to treat patients infected with SARS-CoV-2 variants.


Assuntos
Anticorpos Monoclonais/farmacologia , COVID-19/tratamento farmacológico , SARS-CoV-2/efeitos dos fármacos , Animais , Anticorpos Monoclonais/imunologia , Antivirais/farmacologia , Humanos , Camundongos , SARS-CoV-2/patogenicidade
5.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206616

RESUMO

The biophysical properties of therapeutic antibodies influence their manufacturability, efficacy, and safety. To develop an anti-cancer antibody, we previously generated a human monoclonal antibody (Ab417) that specifically binds to L1 cell adhesion molecule with a high affinity, and we validated its anti-tumor activity and mechanism of action in human cholangiocarcinoma xenograft models. In the present study, we aimed to improve the biophysical properties of Ab417. We designed 20 variants of Ab417 with reduced aggregation propensity, less potential post-translational modification (PTM) motifs, and the lowest predicted immunogenicity using computational methods. Next, we constructed these variants to analyze their expression levels and antigen-binding activities. One variant (Ab612)-which contains six substitutions for reduced surface hydrophobicity, removal of PTM, and change to the germline residue-exhibited an increased expression level and antigen-binding activity compared to Ab417. In further studies, compared to Ab417, Ab612 showed improved biophysical properties, including reduced aggregation propensity, increased stability, higher purification yield, lower pI, higher affinity, and greater in vivo anti-tumor efficacy. Additionally, we generated a highly productive and stable research cell bank (RCB) and scaled up the production process to 50 L, yielding 6.6 g/L of Ab612. The RCB will be used for preclinical development of Ab612.


Assuntos
Anticorpos Monoclonais/química , Modelos Moleculares , Molécula L1 de Adesão de Célula Nervosa/química , Engenharia de Proteínas , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Células CHO , Fenômenos Químicos , Cricetulus , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Molécula L1 de Adesão de Célula Nervosa/antagonistas & inibidores , Engenharia de Proteínas/métodos , Estabilidade Proteica , Termodinâmica
6.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200284

RESUMO

Aberrant expression of glycosphingolipids is a hallmark of cancer cells and is associated with their malignant properties. Disialylated gangliosides GD2 and GD3 are considered as markers of neuroectoderm origin in tumors, whereas fucosyl-GM1 is expressed in very few normal tissues but overexpressed in a variety of cancers, especially in small cell lung carcinoma. These gangliosides are absent in most normal adult tissues, making them targets of interest in immuno-oncology. Passive and active immunotherapy strategies have been developed, and have shown promising results in clinical trials. In this review, we summarized the current knowledge on GD2, GD3, and fucosyl-GM1 expression in health and cancer, their biosynthesis pathways in the Golgi apparatus, and their biological roles. We described how their overexpression can affect intracellular signaling pathways, increasing the malignant phenotypes of cancer cells, including their metastatic potential and invasiveness. Finally, the different strategies used to target these tumor-associated gangliosides for immunotherapy were discussed, including the use and development of monoclonal antibodies, vaccines, immune system modulators, and immune effector-cell therapy, with a special focus on adoptive cellular therapy with T cells engineered to express chimeric antigen receptors.


Assuntos
Anticorpos Monoclonais/farmacologia , Biomarcadores Tumorais/metabolismo , Glicoesfingolipídeos/antagonistas & inibidores , Glicoesfingolipídeos/metabolismo , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Animais , Glicoesfingolipídeos/imunologia , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Transdução de Sinais
7.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200478

RESUMO

Candida auris is a multidrug-resistant fungal pathogen that can cause disseminated bloodstream infections with up to 60% mortality in susceptible populations. Of the three major classes of antifungal drugs, most C. auris isolates show high resistance to azoles and polyenes, with some clinical isolates showing resistance to all three drug classes. We reported in this study a novel approach to treating C. auris disseminated infections through passive transfer of monoclonal antibodies (mAbs) targeting cell surface antigens with high homology in medically important Candida species. Using an established A/J mouse model of disseminated infection that mimics human candidiasis, we showed that C3.1, a mAb that targets ß-1,2-mannotriose (ß-Man3), significantly extended survival and reduced fungal burdens in target organs, compared to control mice. We also demonstrated that two peptide-specific mAbs, 6H1 and 9F2, which target hyphal wall protein 1 (Hwp1) and phosphoglycerate kinase 1 (Pgk1), respectively, also provided significantly enhanced survival and reduction of fungal burdens. Finally, we showed that passive transfer of a 6H1+9F2 cocktail induced significantly enhanced protection, compared to treatment with either mAb individually. Our data demonstrate the utility of ß-Man3- and peptide-specific mAbs as an effective alternative to antifungals against medically important Candida species including multidrug-resistant C. auris.


Assuntos
Anticorpos Monoclonais/farmacologia , Antifúngicos/farmacologia , Candida/imunologia , Candidíase Invasiva/prevenção & controle , Proteínas de Membrana/imunologia , Animais , Anticorpos Monoclonais/imunologia , Candida/efeitos dos fármacos , Candidíase Invasiva/imunologia , Candidíase Invasiva/microbiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Cancer Sci ; 112(9): 3645-3654, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34288263

RESUMO

CD38 expression on myeloma cells is a critical factor affecting the early response to the anti-CD38 antibody daratumumab. However, factors affecting CD38 expression in untreated multiple myeloma are not fully elucidated. In this study, we found that CD38 expression was significantly lower in myeloma patients with the translocation t(11;14)-associated immature plasma cell phenotype, and particularly in those expressing B-cell-associated genes such as PAX5 and CD79A. CD138, a representative marker of plasmacytic differentiation, was also significantly lower in these patients, suggesting that CD38 expression may be associated with the differentiation and maturation stages of myeloma cells. Furthermore, the BCL2/BCL2L1 ratio, a response marker of the BCL2 inhibitor venetoclax, was significantly higher in patients with the immature phenotype expressing B-cell-associated genes. The BCL2/BCL2L1 ratio and CD38 expression were significantly negatively correlated. We also confirmed that patients with translocation t(11;14) expressing B-cell-associated genes were indeed less sensitive to daratumumab-mediated direct cytotoxicity but highly sensitive to venetoclax treatment in ex vivo assays. Moreover, all-trans-retinoic acid, which enhances CD38 expression and induces cell differentiation in myeloma cells, reduced B-cell marker expression and the BCL2/BCL2L1 ratio in myeloma cell lines, leading to reduced efficacy of venetoclax. Venetoclax specifically induces cell death in myeloma with t(11;14), although why patients with translocation t(11;14) show BCL2 dependence is unclear. These results suggest that BCL2 dependence, as well as CD38 expression, are deeply associated with the differentiation and maturation stages of myeloma cells. This study highlights the importance of examining t(11;14) and considering cell maturity in myeloma treatment strategies.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Glicoproteínas de Membrana/metabolismo , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Translocação Genética/genética , ADP-Ribosil Ciclase 1/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linfócitos B/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 14/genética , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/antagonistas & inibidores , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Tretinoína/farmacologia
9.
mBio ; 12(4): e0100221, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34311574

RESUMO

After first emerging in late 2019 in China, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has since caused a pandemic leading to millions of infections and deaths worldwide. Vaccines have been developed and authorized, but the supply of these vaccines is currently limited. With new variants of the virus now emerging and spreading globally, it is essential to develop therapeutics that are broadly protective and bind conserved epitopes in the receptor binding domain (RBD) or the full-length spike protein of SARS-CoV-2. In this study, we generated mouse monoclonal antibodies (MAbs) against different epitopes on the RBD and assessed binding and neutralization of authentic SARS-CoV-2. We demonstrate that antibodies with neutralizing activity, but not nonneutralizing antibodies, lower viral titers in the lungs when administered in a prophylactic setting in vivo in a mouse challenge model. In addition, most of the MAbs cross-neutralize the B.1.351 as well as the B.1.1.7 variant in vitro. IMPORTANCE Cross-neutralization of SARS-CoV-2 variants by RBD-targeting antibodies is still not well understood, and very little is known about the potential protective effect of nonneutralizing antibodies in vivo. Using a panel of mouse monoclonal antibodies, we investigate both of these points.


Assuntos
Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/imunologia , Receptores Virais/imunologia , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/farmacologia , COVID-19/tratamento farmacológico , Chlorocebus aethiops , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Ligação Proteica , Domínios Proteicos/imunologia , SARS-CoV-2/imunologia , Células Vero , Carga Viral
10.
Int J Biol Macromol ; 185: 664-678, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34224755

RESUMO

Nowadays, the targeted imaging probe and drug delivery systems are the novel breakthrough area in the nanomedicine and treatment of various diseases. Conjugation of monoclonal antibodies and their fragments on nanoparticles (NPs) have a remarkable impact on personalized medicine, such that it provides specific internalization and accumulation in the tumor microenvironment. Targeted imaging and early detection of cancer is presumably the strong participant to a diminution in mortality and recurrence of cancer disease that will be the next generation of the imaging device in clinical application. These intelligent delivery systems can deliver therapeutic agents that target cancerous tissue with minimal side effects and a wide therapeutic window. Overall, the linkage between the antibody and NPs is a critical subject and requires precise design and development. The attachment of antibody nanoconjugates (Ab-NCs) on the antigen surface shouldn't affect the function of the antibody-antigen binding. Also, the stability of the antibody nanoconjugates in blood circulation is concerned to avoid the release of drug in non-targeted regions and the possible for specific toxicity while disposal to the desired site. Here, we update the recent progress of Ab-NCs to improve early detection and cancer therapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Biomarcadores Tumorais/imunologia , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacologia , Detecção Precoce de Câncer , Humanos , Nanoconjugados , Neoplasias/imunologia , Patologia Molecular , Medicina de Precisão , Microambiente Tumoral/efeitos dos fármacos
11.
Expert Opin Investig Drugs ; 30(8): 797-801, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34162295

RESUMO

INTRODUCTION: Alzheimer's disease is the leading cause of disability and poor health, takes a huge emotional and financial burden on family caregivers, and is costly. Donanemab (LY3002813) is a new monoclonal antibody that uniquely targets Aß(p3-42), a pyroglutamate form of Amyloid-ß (Aß) exclusively found in plaques. AREAS COVERED: The phase 2 trial of donanemab in participants with early symptomatic Alzheimer's disease, TRAILBLAZER-ALZ. Donanemab reduced cerebral plaque but not tau load and only marginally improved the primary outcome of cognition and activities of daily living (p = 0.04) without altering individual measures of these. EXPERT OPINION: In TRAILBLAZER-ALZ, anticholinesterase use was given at the beginning but not the end of the trial, and thus, it is not known whether changes in this or other medicines were involved in the outcome with donanemab. Tau load (measured with flortuacipir PET) may be a biomarker of cognition but was not altered by donanemab. As there is no clear evidence that removing cerebral amyloid plaques with Aß antibodies, such as donanemab, improves cognition and the activities of daily living in Alzheimer's disease, clinical trials with these agents should be abandoned, and more time and money should spend on further investigating the underlying cause of Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Anticorpos Monoclonais/farmacologia , Atividades Cotidianas , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Cognição/efeitos dos fármacos , Humanos , Placa Amiloide/metabolismo
12.
Nat Commun ; 12(1): 3661, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135340

RESUMO

SARS-CoV-2, the virus responsible for COVID-19, has caused a global pandemic. Antibodies can be powerful biotherapeutics to fight viral infections. Here, we use the human apoferritin protomer as a modular subunit to drive oligomerization of antibody fragments and transform antibodies targeting SARS-CoV-2 into exceptionally potent neutralizers. Using this platform, half-maximal inhibitory concentration (IC50) values as low as 9 × 10-14 M are achieved as a result of up to 10,000-fold potency enhancements compared to corresponding IgGs. Combination of three different antibody specificities and the fragment crystallizable (Fc) domain on a single multivalent molecule conferred the ability to overcome viral sequence variability together with outstanding potency and IgG-like bioavailability. The MULTi-specific, multi-Affinity antiBODY (Multabody or MB) platform thus uniquely leverages binding avidity together with multi-specificity to deliver ultrapotent and broad neutralizers against SARS-CoV-2. The modularity of the platform also makes it relevant for rapid evaluation against other infectious diseases of global health importance. Neutralizing antibodies are a promising therapeutic for SARS-CoV-2.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/química , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Apoferritinas/química , Disponibilidade Biológica , Mapeamento de Epitopos , Humanos , Imunoglobulina G/imunologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Engenharia de Proteínas/métodos , Subunidades Proteicas/química , Glicoproteína da Espícula de Coronavírus/imunologia , Distribuição Tecidual
13.
Nat Commun ; 12(1): 3748, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145250

RESUMO

C. difficile is a major cause of antibiotic-associated gastrointestinal infections. Two C. difficile exotoxins (TcdA and TcdB) are major virulence factors associated with these infections, and chondroitin sulfate proteoglycan 4 (CSPG4) is a potential receptor for TcdB, but its pathophysiological relevance and the molecular details that govern recognition remain unknown. Here, we determine the cryo-EM structure of a TcdB-CSPG4 complex, revealing a unique binding site spatially composed of multiple discontinuous regions across TcdB. Mutations that selectively disrupt CSPG4 binding reduce TcdB toxicity in mice, while CSPG4-knockout mice show reduced damage to colonic tissues during C. difficile infections. We further show that bezlotoxumab, the only FDA approved anti-TcdB antibody, blocks CSPG4 binding via an allosteric mechanism, but it displays low neutralizing potency on many TcdB variants from epidemic hypervirulent strains due to sequence variations in its epitopes. In contrast, a CSPG4-mimicking decoy neutralizes major TcdB variants, suggesting a strategy to develop broad-spectrum therapeutics against TcdB.


Assuntos
Antígenos/metabolismo , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Clostridioides difficile/patogenicidade , Enterocolite Pseudomembranosa/patologia , Proteoglicanas/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Antígenos/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Sítios de Ligação/fisiologia , Anticorpos Amplamente Neutralizantes/farmacologia , Microscopia Crioeletrônica , Enterocolite Pseudomembranosa/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexos Multiproteicos/metabolismo , Ligação Proteica/efeitos dos fármacos , Conformação Proteica , Proteoglicanas/genética
14.
Int J Biol Macromol ; 184: 325-338, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119547

RESUMO

Breast cancer has been one of the top chronic and life-threatening diseases worldwide. Nano-drug therapeutic systems have proved their efficacy as a selective treatment compared to the traditional ones that are associated with serious adverse effects. Here, biodegradable chitosan nanoparticles (CSNPs) were synthesized to provide selective and sustained release of doxorubicin (DOX) within the breast tumor microenvironment. CSNPs surface was modified using Polyethylene glycol (PEG) to enhance their blood circulation timing. To provide high drug selectivity, CSNPs functionalized with two different types of breast cancer-specific monoclonal antibodies (mAb); anti-human mammaglobin (Anti-hMAM) and anti-human epidermal growth factor (Anti-HER2). Anti-hMAM PEGylated DOX loaded CSNPs and Anti-HER2 PEGylated DOX loaded CSNPs nano-formulations were the most cytotoxic against MCF-7 cancer cells than L-929 normal cells compared to free DOX. Finally, we believe that dose-dependent system toxicity of freely ingested DOX can be managed with such targeted nano-formulated drug delivery platforms.


Assuntos
Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Quitosana/química , Doxorrubicina/farmacologia , Polietilenoglicóis/química , Animais , Anticorpos Monoclonais/química , Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Doxorrubicina/química , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Mamoglobina A/antagonistas & inibidores , Camundongos , Nanopartículas , Receptor ErbB-2/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos
15.
Indian J Pharmacol ; 53(3): 226-228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34169908

RESUMO

Although many potent drugs have been used for cytokine storm, mortality is high for patients with coronavirus disease-2019 (COVID-19), which is followed up in the intensive care unit. Interferons (IFNs) are the major cytokines of the antiviral defense system released from many cell types. However, IFN-γ plays a key role in both primary and secondary cytokine storms. If the cytokine storm is not treated urgently, it will be fatal; therefore, it should be treated immediately. Anakinra, an interleukin-1 (IL-1) antagonist, tocilizumab, an IL-6 antagonist, and Janus kinase (JAK) inhibitors are successfully used in cytokine storm caused by COVID-19. However, sometimes, despite these treatments, the patient's clinical course does not improve. Emapalumab (Eb) is the human immunoglobulin G1 monoclonal antibody and is a potent and noncompetitive antagonist of IFN-γ. Eb can be life saving for cytokine storm caused by COVID-19, which is resistant to anakinra, tocilizumab, and JAK inhibitors.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , COVID-19/tratamento farmacológico , Síndrome da Liberação de Citocina/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Inibidores de Janus Quinases/uso terapêutico , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/farmacologia , Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , COVID-19/epidemiologia , COVID-19/imunologia , Síndrome da Liberação de Citocina/epidemiologia , Síndrome da Liberação de Citocina/imunologia , Progressão da Doença , Farmacorresistência Viral , Humanos , Interferon gama/antagonistas & inibidores , Interferon gama/imunologia , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Interleucinas/antagonistas & inibidores , Interleucinas/imunologia , Inibidores de Janus Quinases/farmacologia , Recidiva
16.
Nature ; 596(7870): 103-108, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34153975

RESUMO

Rapidly emerging SARS-CoV-2 variants jeopardize antibody-based countermeasures. Although cell culture experiments have demonstrated a loss of potency of several anti-spike neutralizing antibodies against variant strains of SARS-CoV-21-3, the in vivo importance of these results remains uncertain. Here we report the in vitro and in vivo activity of a panel of monoclonal antibodies (mAbs), which correspond to many in advanced clinical development by Vir Biotechnology, AbbVie, AstraZeneca, Regeneron and Lilly, against SARS-CoV-2 variant viruses. Although some individual mAbs showed reduced or abrogated neutralizing activity in cell culture against B.1.351, B.1.1.28, B.1.617.1 and B.1.526 viruses with mutations at residue E484 of the spike protein, low prophylactic doses of mAb combinations protected against infection by many variants in K18-hACE2 transgenic mice, 129S2 immunocompetent mice and hamsters, without the emergence of resistance. Exceptions were LY-CoV555 monotherapy and LY-CoV555 and LY-CoV016 combination therapy, both of which lost all protective activity, and the combination of AbbVie 2B04 and 47D11, which showed a partial loss of activity. When administered after infection, higher doses of several mAb cocktails protected in vivo against viruses with a B.1.351 spike gene. Therefore, many-but not all-of the antibody products with Emergency Use Authorization should retain substantial efficacy against the prevailing variant strains of SARS-CoV-2.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/farmacologia , Anticorpos Antivirais/uso terapêutico , COVID-19/virologia , Testes de Neutralização , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , COVID-19/genética , COVID-19/imunologia , COVID-19/prevenção & controle , Chlorocebus aethiops , Feminino , Humanos , Masculino , Mesocricetus/imunologia , Mesocricetus/virologia , Camundongos , Camundongos Transgênicos , Profilaxia Pós-Exposição , Profilaxia Pré-Exposição , SARS-CoV-2/genética , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
17.
Commun Biol ; 4(1): 772, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162985

RESUMO

Monoclonal antibodies (mAb) and natural ligands targeting costimulatory tumor necrosis factor receptors (TNFR) exhibit a wide range of agonistic activities and antitumor responses. The mechanisms underlying these differential agonistic activities remain poorly understood. Here, we employ a panel of experimental and clinically-relevant molecules targeting human CD40, 4-1BB and OX40 to examine this issue. Confocal and STORM microscopy reveal that strongly agonistic reagents induce clusters characterized by small area and high receptor density. Using antibody pairs differing only in isotype we show that hIgG2 confers significantly more receptor clustering than hIgG1 across all three receptors, explaining its greater agonistic activity, with receptor clustering shielding the receptor-agonist complex from further molecular access. Nevertheless, discrete receptor clustering patterns are observed with different hIgG2 mAb, with a unique rod-shaped assembly observed with the most agonistic mAb. These findings dispel the notion that larger receptor clusters elicit greater agonism, and instead point to receptor density and subsequent super-structure as key determinants.


Assuntos
Receptores do Fator de Necrose Tumoral/agonistas , Animais , Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Antígenos CD40/agonistas , Antígenos CD40/química , Linhagem Celular , Humanos , Imunoglobulina G/farmacologia , Camundongos , Microscopia Confocal , Receptores OX40/agonistas , Receptores do Fator de Necrose Tumoral/química , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/agonistas
18.
Front Immunol ; 12: 611256, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34079536

RESUMO

Ulcerative colitis (UC) is a chronic relapsing disorder of the colonic tract, characterized by a dysregulated innate and adaptive immune response to gut microbiota that contributes to the perpetuation of intestinal inflammatory processes. The Interleukin (IL) 23/IL17 axis has been reported to play a key role in UC pathogenesis promoting Th17 cells and cytokines-related immune response. Recently, the blockade of IL23/IL17 pathways has been raised enormous interest in the treatment o several chronic inflammatory disorders. In this review, we summarize the emerging results from clinical trials that evoked both promise and discouragement in IL23/IL17 axis in the treatment of UC. Targeting IL23 p40 through Ustekinumab results safe and effective to induce and maintain clinical remission, low inflammatory indexes, mucosal healing, and a better quality of life. Studies targeting IL23 p19 through Mirikizumab, Risankizumab, Brazikumab and Guselkumab are still ongoing. To date, no clinical studies targeting IL17 pathway are ongoing in UC. IL-17 targeting is thought to have a context-dependent biological effect, based on whether cytokine is selectively targeted or if its function is dampened by the upstream block of IL23.


Assuntos
Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Imunomodulação/efeitos dos fármacos , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Gerenciamento Clínico , Suscetibilidade a Doenças , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Humanos , Terapia de Alvo Molecular , Resultado do Tratamento , Ustekinumab/farmacologia , Ustekinumab/uso terapêutico
19.
Oncoimmunology ; 10(1): 1915561, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33996267

RESUMO

Most monoclonal antibodies (MAbs), including immune checkpoint inhibitor MAbs, are delivered intravenously (i.v.) to patients. Recent clinical studies have demonstrated that some anti-PD1 MAbs may also be delivered subcutaneously (s.c.), with clinical outcomes similar of those obtained with i.v.-delivered agents. Bintrafusp alfa, a first-in-class bifunctional fusion protein composed of the extracellular domain of the human transforming growth factor ß receptor II (TGF-ßRII or TGF-ß "trap") fused to the heavy chain of an IgG1 antibody blocking programmed death ligand 1 (anti-PDL1), was designed to target two key immunosuppressive pathways in the tumor microenvironment (TME). Bintrafusp alfa is currently being administered i.v. in clinical studies. The studies reported here demonstrate that systemic or s.c. delivery of bintrafusp alfa, each administered at five different doses, induces similar anti-tumor effects in breast and colorectal carcinoma models. An interrogation of the TME for CD8+ and CD4+ T cells, regulatory T cells (Tregs), monocytic myeloid-derived suppressor cells (M-MDSCs) and granulocytic (G) MDSCs showed similar levels and phenotype of each cell subset when bintrafusp alfa was given systemically or s.c. Subcutaneous administration of bintrafusp alfa also sequestered TGFß in the periphery at similar levels seen with systemic delivery. To our knowledge, this is the most comprehensive preclinical evaluation of any checkpoint inhibitor MAb given s.c. vs systemically, and the first to demonstrate this phenomenon using a bifunctional agent. These studies provide preclinical rationale to explore s.c. approaches for bintrafusp alfa in the clinic.


Assuntos
Antineoplásicos Imunológicos , Neoplasias , Anticorpos Monoclonais/farmacologia , Antineoplásicos Imunológicos/farmacologia , Humanos , Fatores Imunológicos/farmacologia , Neoplasias/tratamento farmacológico , Microambiente Tumoral
20.
Nat Protoc ; 16(7): 3639-3671, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34035500

RESUMO

As exemplified by the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, there is a strong demand for rapid high-throughput isolation pipelines to identify potent neutralizing antibodies for prevention and therapy of infectious diseases. However, despite substantial progress and extensive efforts, the identification and production of antigen-specific antibodies remains labor- and cost-intensive. We have advanced existing concepts to develop a highly efficient high-throughput protocol with proven application for the isolation of potent antigen-specific antibodies against human immunodeficiency virus 1, hepatitis C virus, human cytomegalovirus, Middle East respiratory syndrome coronavirus, SARS-CoV-2 and Ebola virus. It is based on computationally optimized multiplex primer sets (openPrimeR), which guarantee high coverage of even highly mutated immunoglobulin gene segments as well as on optimized antibody cloning and production strategies. Here, we provide the detailed protocol, which covers all critical steps from sample collection to antibody production within 12-14 d.


Assuntos
Anticorpos Neutralizantes/isolamento & purificação , COVID-19/imunologia , Ensaios de Triagem em Larga Escala/métodos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Doenças Transmissíveis , Humanos , Imunoglobulina G/imunologia , Pandemias , SARS-CoV-2/imunologia
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