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1.
Chem Biodivers ; 20(8): e202300760, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37427893

RESUMO

Mn(II) and Cu(II) complexes having the formula [M(L)2 ]X2 of ligand, i. e., 2-acetyl-5-methylfuranthiosemicarbazone were synthesized. Various analytical and spectroscopic techniques described the structure of synthesized complexes. Molar conductance confirmed the electrolytic nature of the complexes. The theoretical study of the complexes explained the structural property and reactivity. The chemical reactivity, interaction and stability of the ligand and metal complexes were studied with the help of global reactivity descriptors. MEP analysis was used to investigate the charge transfer in the ligand. The biological potency was evaluated against two bacteria and two fungi. Complexes demonstrated superior inhibitory action to ligand. The inhibitory effect was also checked at the atomic scale using molecular docking, which confirmed the experimental results. Cu(II) complex was shown to have the most inhibitory effect in experimental and theoretical studies. To check the bioavailability and drug-likeness, ADME analysis was also done.


Assuntos
Complexos de Coordenação , Tiossemicarbazonas , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Simulação de Acoplamento Molecular , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Ligantes , Bases de Schiff/química , Metais/química , Cobre/química , Testes de Sensibilidade Microbiana
2.
Drug Discov Today Technol ; 37: 41-50, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34895654

RESUMO

The key factor in successful development and marketing of biosimilar antibodies is a deep understanding of their critical quality attributes and the ability to control them. Comprehensive functional characterization is therefore at the heart of the process and is a crucial part of regulatory requirements. Establishment of a scientifically sound molecule-specific functional in vitro assay panel requires diligent planning and high flexibility in order to respond to both regulatory requirements and the ever-changing demands relevant to the different stages of the development and production process. Relevance of the chosen assays to the in vivo mechanism of action is of key importance to the stepwise evidence-based demonstration of biosimilarity. Use of a sound interdisciplinary approach and orthogonal state-of-the-art techniques is also unavoidable for gaining in-depth understanding of the biosimilar candidate. The aim of the present review is to give a snapshot on the methodic landscape as depicted by the available literature discussing the in vitro techniques used for the functional characterization of approved biosimilar therapeutic antibodies. Emerging hot topics of the field and relevant structure-function relationships are also highlighted.


Assuntos
Medicamentos Biossimilares
3.
Molecules ; 24(19)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547184

RESUMO

Transferon® is a blood product with immunomodulatory properties constituted by a complex mixture of peptides obtained from a human dialyzable leukocyte extract (DLE). Due to its complex nature, it is necessary to demonstrate batch consistency in its biological activity. Potency is the quantitative measure of biological activity and is also a quality attribute of drugs. Here we developed and validated a proliferation assay using Jurkat cells exposed to azathioprine, which is intended to determine the potency of Transferon® according to international guidelines for pharmaceuticals. The assay showed a linear response (2.5 to 40 µg/mL), coefficients of variation from 0.7 to 13.6% demonstrated that the method is precise, while r2 = 0.97 between the nominal and measured values obtained from dilutional linearity showed that the method is accurate. We also demonstrated that the cell proliferation response was specific for Transferon® and was not induced by its vehicle nor by other peptide complex mixtures (glatiramer acetate or hydrolyzed collagen). The bioassay validated here was used to assess the relative potency of eight released batches of Transferon® with respect to a reference standard, showing consistent results. The collective information from the validation and the assessment of several batches indicate that the bioassay is suitable for the release of Transferon®.


Assuntos
Bioensaio/métodos , Proliferação de Células/efeitos dos fármacos , Humanos , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia
4.
Allergol Immunopathol (Madr) ; 44(3): 232-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26321600

RESUMO

BACKGROUND: Gramineae bee-collected pollen is identified as being at the origin of allergic accidents but the biological potency of Gramineae bee-collected pollen is not well known. Cereal grasses (e.g., Zea) and European wild forage grasses (FG) are contained in bee-collected pollen. METHOD: In this experiment, Zea-mass and FG-mass were identified in bee pollen mass and the proportion of Zea and of FG was calculated using the bee pollen melissopalynology spectrum. Skin reactivity to Zea and to FG were assessed by measuring wheal diameters (W) from skin prick tests using three serial dilutions of bee-collected pollen on 10 allergic patients to Gramineae, in order to calculate the relationship between Zea mass (Masszea) or FG mass (MassFG) in bee pollen and skin reactivity. RESULTS: The linear function Log10(WFG)=0.24(Log10(MassFG))+0.33 (R=0.99) was established using a bee pollen sample with 0.168mg of FG pollen per mg. The linear function Log10(Wzea)=0.23(Log10(Masszea))+0.14 (R=0.99) was established using a bee pollen sample with 0.983mg of Zea pollen per mg. Gramineae allergens seem to be little altered by bee secretions. Gramineae bee pollen retains its allergenic capacity but it depends on the members of the Gramineae family. CONCLUSIONS: To our knowledge this is the first time it has been shown that skin reactivity to Gramineae is proportional to the absolute Gramineae mass contained in the bee-collected pollen and that it depends on the members of the Gramineae family.


Assuntos
Alérgenos/imunologia , Abelhas/imunologia , Grão Comestível/imunologia , Hipersensibilidade/imunologia , Pólen/imunologia , Zea mays/imunologia , Adolescente , Adulto , Animais , Asma/imunologia , Conjuntivite Alérgica/imunologia , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica Sazonal/imunologia , Testes Cutâneos , Adulto Jovem
5.
Eur Ann Allergy Clin Immunol ; 47(6): 218-24, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26549340

RESUMO

Bee product mugwort is identified as being at the origin of allergic accidents but the biological potency of Artemisia contained in bee pollen is not well known. In this experiment, Artemisia mass was identified in bee pollen mass and after having calculated the proportion of Artemisia using the bee pollen melissopalynology spectrum. Skin reactivity to Artemisia was assessed by measuring wheal diameters (W) from skin prick tests using three serial dilutions of bee pollen on 11 allergic patients to Artemisia, in order to calculate the relationship between Artemisia mass (Massartemisia) in bee pollen and skin reactivity. The dose-response power regression curve (Wartemisia)=3.328 (Massartemisia)0.297 (R2=0.9947) and the linear function Log10 (Wartemisia)=0.297 (Log10 (Massartemisia)+0.520 (R=0.9974)) were established using a bee pollen sample with 0.246 mg of Artemisia pollen per mg. Mugwort allergens seem to be little or not altered by bee secretions and bee pollen retains its allergenic capacity. To our knowledge this is the first time it has been shown that skin reactivity of patients allergic to mugwort is proportional to the absolute mugwort mass contained in the bee pollen.


Assuntos
Alérgenos/imunologia , Artemisia/imunologia , Abelhas , Proteínas de Plantas/imunologia , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia , Adulto , Alérgenos/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Testes Intradérmicos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Proteínas de Plantas/administração & dosagem , Valor Preditivo dos Testes , Rinite Alérgica Sazonal/diagnóstico
6.
Biochem Biophys Res Commun ; 451(4): 650-5, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25130460

RESUMO

Cecropin A-melittin (CAM), a chimeric antimicrobial peptide with potent antimicrobial activity, is threatened by some special extracellular proteases when used to deal with certain drug-resistant pathogenic microbes in the gastrointestinal tract. Thus, a four-tryptophan-substitution mutant (CAM-W) from CAM was developed via the replacement of special amino acid residues to enhance the antimicrobial potency and to improve the proteolytic stability of this agent. The pharmaceutical index of CAM-W was investigated, with a focus on biological potency, cytotoxicity, and proteolytic stability, as well as pH and thermal resistance. CAM-W exhibited potent antimicrobial activity and was approximately 3-12 times higher than that of CAM. CAM-W also exhibited a strong antifungal activity against a series of common pathogenic fungi, in a lower IC50 range between 2.1mg/L and 3.3mg/L than that of its reference CAM ranging from 9.8mg/L to 14.2mg/L. Besides, CAM-W showed moderate cytotoxicity (IC50>300mg/L) in erythrocyte lysis test. In addition, CAM-W overcame challenges under various conditions, including specific temperatures (20, 30, 40, 50, 60, 70, 80, and 90°C), pH values (2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, and 9.0), and proteases (trypsin, pepsin, human neutrophil elastase, Pseudomonas aeruginosa elastase, and Staphylococcus aureus V8 protease) that are commonly present in human gastrointestinal tract. These results suggest that the four-tryptophan-substitution can confer CAM-W with a high pharmaceutical index, which is important for CAM-W to become a potential alternative to conventional antibiotics against bacteria and fungi associated with gastroenteritis.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Estabilidade de Medicamentos , Meliteno/genética , Anti-Infecciosos , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Gastroenterite/tratamento farmacológico , Gastroenterite/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases , Proteólise , Temperatura
7.
Front Pharmacol ; 15: 1405342, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38953103

RESUMO

Angelica sinensis is a long-standing medicine used by Chinese medical practitioners and well-known for its blood-tonic and blood-activating effects. Ferulic acid, ligustilide, and eugenol in Angelica sinensis activate the blood circulation; however, the material basis of their blood-tonic effects needs to be further investigated. In this study, five homogeneous Angelica sinensis polysaccharides were isolated, and their sugar content, molecular weight, monosaccharide composition, and infrared characteristics determined. Acetylphenylhydrazine (APH) and cyclophosphamide (CTX) were used as inducers to establish a blood deficiency model in mice, and organ indices, haematological and biochemical parameters were measured in mice. Results of in vivo hematopoietic activity showed that Angelica sinensis polysaccharide (APS) could elevate erythropoietin (EPO), granulocyte colony-stimulating factor (G-CSF), and interleukin-3 (IL-3) serum levels, reduce tumor necrosis factor-α (TNF-α) level in mice, and promote hematopoiesis in the body by regulating cytokine levels. Biological potency test results of the in vitro blood supplementation indicated strongest tonic activity for APS-H2O, and APS-0.4 has the weakest haemopoietic activity. The structures of APS-H2O and APS-0.4 were characterized, and the results showed that APS-H2O is an arabinogalactan glycan with a main chain consisting of α-1,3,5-Ara(f), α-1,5- Ara(f), ß-1,4-Gal(p), and ß-1,4-Gal(p)A, and two branched chains of ß-t-Gal(p) and α-t-Glc(p) connected to each other in a (1→3) linkage to α-1,3,5-Ara(f) on the main chain. APS-0.4 is an acidic polysaccharide with galacturonic acid as the main chain, consisting of α-1,4-GalA, α-1,2-GalA, α-1,4-Gal, and ß-1,4-Rha. In conclusion, APS-H2O can be used as a potential drug for blood replenishment in patients with blood deficiency, providing a basis for APS application in clinical treatment and health foods, as well as research and development of new polysaccharide-based drugs.

8.
Pharmaceuticals (Basel) ; 15(7)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35890084

RESUMO

The present work aims to assess the biological potential of polyphenolic compounds in different parts (flowers, leaves, stems, and roots) of Stachys palustris L. Towards secondary metabolites profile, 89 polyphenolic compounds (PCs) were identified by UPLC-PDA-ESI-TQD-MS/MS, with a total average content of 6089 mg/100 g of dry matter (d.m.). In terms of biological activity, antioxidant activity (radical activity, reducing power), digestive enzyme inhibitory (α-glucosidase, α-amylase, pancreatic lipase) effect, and antiproliferative activity (inhibition of cell viability and induction of apoptosis in different human cancer cell lines) were explored. Leaves, flowers, stems, and roots of S. palustris L. have not been studied in this regard until now. Vescalagin and cocciferin d2, isoverbascoside (verbascoside), luteolin 6-C-glucoside, luteolin 6-C-galactoside, apigenin 6-C-glucoside, (-)-epicatechin, ellagic acid, and malvidin 3-O-diglucoside were detected as main ingredients in the studied parts. Methanolic extract of S. palustris L. leaves and flowers revealed the highest amount of PCs with the strongest antiradical (18.5 and 15.6 mmol Trolox equivalent (TE)/g d.m., respectively) and reducing power effects (7.3 and 5.6 mmol TE/g d.m.). Leaf extracts exhibited better α-amylase and pancreatic lipase inhibition effects, while flower extracts exhibited better α-glucosidase inhibition effect. Regarding antiproliferative activity, extracts of the leaves and flowers significantly reduced cell viability and induced a high level of apoptosis in human lung, pancreatic, bladder, and colon cancer cell lines, as well as in human acute myeloid leukemia; whereas the extracts from stems and roots revealed the weaker effects. The results of this work showed anti-proliferative and potentially anti-diabetic, anti-obesity properties of S. palustris L., especially for flowers and leaves, which may have wide potential applications in the functional food, special food, pharmaceutical, cosmetics industries, and/or in medicine.

9.
Int J Biol Macromol ; 180: 494-509, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33684428

RESUMO

Ziv-aflibercept (aflibercept) is a recombinant fusion protein which combines the portions of human vascular endothelial growth factor receptors extracellular domains fused to the Fc portion of human IgG1. It is a highly sialylated glycoprotein with 5 N-glycosylation sites. In this study, a comprehensive strategy for comparability study of the complex glycosylation was developed between aflibercept and the biosimilar candidate including the investigations on N-glycosylation sites, site occupancy, site-specific glycoforms, released glycans and sialic acids. The results indicated that same N-glycosylation sites were identified, site occupancy were 100% except N68 site, site-specific glycoforms and released glycans showed similar glycan species, contents of NANA were at a same level for two products. Minor differences were found between two products. The biosimilar candidate presented lower level of aglycosylation, lower level of glycans containing one terminal sialic acid, higher level of glycans containing two terminal sialic acids, higher level of G0F and Man5, lower level of G1F and G2F compared with aflibercept. However, further studies exhibited no differences were observed in the cell-based biological potency and Fc effector function. Moreover, the biosimilar candidate showed a similar pharmacokinetics curve and bioequivalence compared with aflibercept.


Assuntos
Medicamentos Biossimilares/metabolismo , Polissacarídeos/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Ácidos Siálicos/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Medicamentos Biossimilares/farmacocinética , Células CHO , Linhagem Celular Tumoral , Células Cultivadas , Cromatografia Líquida/métodos , Cricetinae , Cricetulus , Glicopeptídeos/química , Glicopeptídeos/genética , Glicopeptídeos/metabolismo , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Humanos , Macaca fascicularis , Mapeamento de Peptídeos/métodos , Proteínas Recombinantes de Fusão/farmacocinética , Espectrometria de Massas em Tandem/métodos
10.
Toxicol Sci ; 184(1): 154-169, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34453843

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are some of the most prominent organic contaminants in human blood. Although the toxicological implications of human exposure to perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are well established, data on lesser-understood PFAS are limited. New approach methodologies (NAMs) that apply bioinformatic tools to high-throughput data are being increasingly considered to inform risk assessment for data-poor chemicals. The aim of this study was to compare the potencies (ie, benchmark concentrations: BMCs) of PFAS in primary human liver microtissues (3D spheroids) using high-throughput transcriptional profiling. Gene expression changes were measured using TempO-seq, a templated, multiplexed RNA-sequencing platform. Spheroids were exposed for 1 or 10 days to increasing concentrations of 23 PFAS in 3 subgroups: carboxylates (PFCAs), sulfonates (PFSAs), and fluorotelomers and sulfonamides. PFCAs and PFSAs exhibited trends toward increased transcriptional potency with carbon chain-length. Specifically, longer-chain compounds (7-10 carbons) were more likely to induce changes in gene expression and have lower transcriptional BMCs. The combined high-throughput transcriptomic and bioinformatic analyses support the capability of NAMs to efficiently assess the effects of PFAS in liver microtissues. The data enable potency ranking of PFAS for human liver cell spheroid cytotoxicity and transcriptional changes, and assessment of in vitro transcriptomic points of departure. These data improve our understanding of the possible health effects of PFAS and will be used to inform read-across for human health risk assessment.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácidos Alcanossulfônicos/toxicidade , Ácidos Carboxílicos , Fluorocarbonos/toxicidade , Humanos , Fígado , Transcriptoma
11.
Environ Int ; 136: 105455, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945694

RESUMO

The ever-increasing number of chemicals and complex mixtures demands a high-throughput and cost-effective approach for chemical safety assessment. High-throughput transcriptomics (HTT) is promising in investigating genome-scale perturbation of chemical exposure in concentration-dependent manner. However, the application of HTT has been limited due to lack of methodology for single chemicals and mixture assessment. This study aimed to evaluate the ability of a newly-developed human reduced transcriptomics (RHT) approach to assess pathway-based profiles of single chemicals, and to develop a biological pathway-based approach for benchmarking mixture potency using single chemical-based prediction model. First, concentration-dependent RHT were used to qualitatively and quantitatively differentiate pathway-based patterns of different chemicals, using three model toxicants, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), triclosan (TCS) and 5-Chloro-6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (5-Cl-6-OH-BDE-47). AHR-regulated genes and pathways were most sensitively induced by TCDD, while TCS and 5-Cl-6-OH-BDE-47 were much less potent in AHR-associated activation, which was concordant with known MoA of each single chemical. Second, two artificial mixtures and their components of twelve individual chemicals were performed with concentration-dependent RHT. Concentration addition (CA) and independent action (IA) models were used to predict transcriptional potency of mixtures from transcriptomics of individual chemicals. For overall bioactivity, CA and IA models can both predict potency of observed responses within 95% confidence interval. For specific biological processes, multiple biological processes such as hormone signaling and DNA damage can be predicted using CA models for mixtures. The concentration-dependent RHT can provide a powerful approach for qualitative and quantitative assessment of biological pathway perturbated by environment chemical and mixtures.


Assuntos
Poluentes Ambientais , Dibenzodioxinas Policloradas , Transcriptoma , Animais , Biologia Computacional , Poluentes Ambientais/toxicidade , Humanos , Modelos Químicos , Ratos , Ratos Sprague-Dawley
12.
Environ Int ; 139: 105703, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32259755

RESUMO

The determination of PM2.5-induced biological response is essential for understanding the adverse health risk associated with PM2.5 exposure. In this study, we conducted cell-based bioassays to measure the toxic effects of PM2.5 exposure, including cytotoxicity, oxidative stress, genotoxicity and inflammatory response. The concentration-response relationship was analyzed by benchmark dose (BMD) modeling and the BMDL10 was used to estimate the biological potency of PM2.5 exposure. PM2.5 samples were collected from three typical megacities of China (Beijing, BJ; Wuhan, WH; Guangzhou, GZ) in typical seasons (winter and summer). The total PM, water-soluble fractions (WSF), and organic extracts (OE) were prepared and subjected to examination of toxic effects. The biological potencies for cytotoxicity, oxidative stress and genotoxicity were generally higher in winter samples, while the inflammatory potency of PM2.5 was higher in summer samples. The relative health risk (RHR) was determined by integration of the biological potencies and the cumulative exposure level, and the ranks of RHR were BJ-W > WH-W > BJ-S > WH-S > GZ-W > GZ-S. Notably, we note that different PM2.5 compositions were associated with distinct biological effects, and the health effects distribution of PM2.5 varied in regions and seasons. These findings demonstrate that the approach of integrated cell-based bioassays could be used for the evaluation of health effects of PM2.5 exposure.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Pequim , Bioensaio , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Material Particulado/toxicidade , Medição de Risco , Estações do Ano
13.
Environ Pollut ; 260: 114011, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31991362

RESUMO

Neonicotinoid insecticides have posed a great threat to non-target organisms, yet the mechanisms underlying their toxicity are not well characterized. Major modes of action (MoAs) of imidacloprid were analyzed in an aquatic insect Chironomus dilutus. Lethal and sublethal outcomes were assessed in the midges after 96-h exposure to imidacloprid. Global transcriptomic profiles were determined using de novo RNA-sequencing to more holistically identify toxicity pathways. Transcriptional 10% biological potency values derived from ranked KEGG pathways and GO terms were 0.02 (0.01-0.08) (mean (95% confidence interval) and 0.05 (0.04-0.06) µg L-1, respectively, which were more sensitive than those from phenotypic traits (10% lethal concentration: 0.44 (0.23-0.79) µg L-1; 10% burrowing behavior concentration: 0.30 (0.22-0.43) µg L-1). Major MoAs of imidacloprid in aquatic species were identified as follows: the activation of nicotinic acetylcholine receptors (nAChRs) induced by imidacloprid impaired organisms' nerve system through calcium ion homeostasis imbalance and mitochondrial dysfunction, which posed oxidative stress and DNA damage and eventually caused death of organisms. The current investigation highlighted that imidacloprid affected C. dilutus at environmentally relevant concentrations, and elucidated toxicity pathways derived from gene alteration to individual outcomes, calling for more attention to toxicity of neonicotinoids to aquatic organisms.


Assuntos
Chironomidae , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Poluentes Químicos da Água , Animais , Insetos , Nitrocompostos , Toxicogenética
14.
J Pharm Sci ; 109(9): 2684-2698, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32473898

RESUMO

Monoclonal antibody (mAb) products are presently the dominant class of therapeutic proteins. When stressed, they are known to be prone to molecular instabilities like aggregation, fragmentation, oxidation and reduction, of which aggregation is typically the most significant concern. These stresses may be experienced during manufacturing, storage, filling, formulation development and shipping. This paper investigates how mAb aggregates generated by a variety of mechanical, thermal and chemical stresses impact the biological activity of a biotherapeutic. Increased aggregation resulted in a decrease in biological activity, as confirmed by cell based assays such as antibody dependent cell mediated cytotoxicity (ADCC) and complement dependent cytotoxicity (CDC) and ligand binding assays such as surface plasmon resonance (SPR). It was observed that aggregates formed due to extreme pH (pH 3.5 and pH 11.0), stirring (1 d stir and 3 d stir), thermal stress, and oxidation via CuSO4 have the most impact on potency of the therapeutic. In contrast, aggregates formed due to stresses from pipetting, milder pH (4.3 and 8.5), oxidation via H2O2, freeze-thaw (Ft-slow and Ft-fast) have relatively less impact on the potency of the mAb biotherapeutic. The results affirm that understanding of the mechanism of aggregation is critical for achieving consistent product quality and the resulting efficacy.


Assuntos
Anticorpos Monoclonais , Antineoplásicos Imunológicos , Citotoxicidade Celular Dependente de Anticorpos , Peróxido de Hidrogênio , Rituximab
15.
Biotechnol Rep (Amst) ; 19: e00259, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30023317

RESUMO

Circular dichroism (CD) in far-UV region was employed to study the extent of changes occurred in the secondary structures of recombinant streptokinase (rSK), solubilized from inclusion bodies (IBs) by different chemicals and refolded/purified by chromatographic techniques. The secondary structure distribution of rSK, obtained following different chemical solubilization systems, was varied and values in the range of 12.4-14.5% α-helices, 40-51% ß-sheets and 35.5-48.3% turns plus residual structures were found. With reducing the concentration of chemicals during IB solubilization, the content of turns plus random coils was diminished and simultaneously the amounts of α- and ß-sheets were increased. These changes in the secondary structures would lower the hydrophobicity along with the chance of protein aggregation and expose the hydrophilic regions of the protein. Therefore, these alterations in the secondary structures, occurred following efficient IBs solubilization by low concentration of chemicals, could be related to enhancement in rSK biological potency previously observed.

16.
Protein Pept Lett ; 25(12): 1149-1154, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30381053

RESUMO

BACKGROUND: Research has been directed at the optimization of insulin for medicinal purposes. An insulin analog that could be reversibly activated might provide more precise pharmacokinetic control and broaden the inherent therapeutic index of the hormone. The prospect of using intramolecular structural constraint to reversibly inactive insulin might constitute the first step to achieving such an optimized analog. Chemically crosslinked insulin analogs have been reported where two amines are covalently linked by reaction with symmetrical bifunctional active esters. There is little selectivity in this synthetic approach to molecular constraint with multiple derivatives being formed. OBJECTIVE: To systematically evaluate the synthesis of covalently crosslinked insulin analogs by asymmetric methods and the biological consequences. METHOD: We report synthesis of amine crosslinked insulin analogs via a two-step procedure. The stepwise approach was initiated by amide bond formation and followed by second site alkylation to produce site-specific, cross-linked insulin analogs. RESULTS: A set of unique insulin analogs crosslinked at the two of the three native amines were synthesized. They were chemical characterized and assessed by in vitro bioanalysis to result in a significant and reasonably consistent reduction in biological potency. CONCLUSION: We achieved an unambiguous two-step synthesis of several crosslinked insulin analogs differing in location of the chemical tether. Bioanalysis demonstrated the ability of the molecular constraint to reduce bioactivity. The results set the stage for in vivo assessment of whether such a reduction in potency can be used pharmacologically to establish a constrained hormone upon which reversible tethering might be subsequently introduced.


Assuntos
Aminas/química , Insulina/análogos & derivados , Animais , Reagentes de Ligações Cruzadas/química , Humanos , Insulina/síntese química , Insulina/química , Insulina/farmacocinética , Estrutura Molecular
17.
Rev. Inst. Adolfo Lutz (Online) ; 74(3): 178-189, jul.-set. 2015. tab, graf
Artigo em Português | LILACS, SES-SP, SESSP-CTDPROD, SES-SP, SESSP-ACVSES, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: lil-786785

RESUMO

A monografia farmacopeica da vacina tríplice viral (sarampo/caxumba/rubéola) exige a validação de desempenho do ensaio de potência utilizando-se apropriado material de referência (MR). Com o intuito de estabelecer o primeiro MR de trabalho (MRT) nacional para a vacina tríplice viral, foi realizado o estudo colaborativo nacional com a participação de duas únicas instituições que executam o ensaio de potência desta vacina, o Instituto de Tecnologia em Imunobiológicos (Bio-Manguinhos, produtor nacional) e o Instituto Nacional de Controle de Qualidade em Saúde.O material candidato (cMRTBio), preparado pelo produtor, foi avaliado pelos laboratórios participantes utilizando-se as respectivas metodologias in-house de determinação de potência. O cMRTBio foi considerado apropriado como MR in-house por estar em concordância com as especificações recomendadas nas normativas de compêndios, a saber: variações intra- (< 5 %), inter-ensaios (< 10 %) e entre laboratórios (< 10 %) abaixo dos limites aceitáveis; e potência estimada (log10 CCID50/DH) em 3,72 para sarampo, 4,80 para caxumba e 3,70 para rubéola. Este trabalho reflete o compromisso do único produtor nacional da vacina tríplice viral com a saúde pública, descrevendo-se a expansão da tecnologia, o cumprimento às diretrizes internacionais, o cuidado com o controle da qualidade e culminância para a autossuficiência nacional na produção de vacinas.


The pharmacopoeia monograph for the measles/mumps and rubella (MMR) triple vaccine demands to perform the validation of the potency assay by using the suitable reference material (MR). Aiming at establishing the firstwork MR (MRT) for the MMR triple vaccine, a national collaborative study was performed with the participation of the two unique national institutions working on the vaccine potency evaluation test, the Imunobiological Technology Institute (Bio-Manguinhos, national manufacturer) and the National Institute for Quality Control in Health. The candidate product (cMRTBio) prepared by the manufacturer was evaluated by the participant laboratories by employing the respective in-house methodologies for determining the potency. The cMRTBio was considered suitable as in-house MR, according to the specifications based on the normative compendia, being the intra-assay (< 5 %), inter-assay(< 10 %) and between laboratories variations (< 10 %) below the acceptable limits, and the estimate potency(log10 CCID50/DH) in 3.72 for measles, 4.80 for mumps and 3.70 for rubella. This study reflects the commitment of the unique national MMR vaccine producer to the public health, describing the expansion of technology,the compliance with international guidelines and the careful quality control, leading to the national self-sufficiency in the vaccine production.


Assuntos
Controle de Qualidade , Farmacopeias como Assunto , Vacina contra Sarampo-Caxumba-Rubéola , Vacinas
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