RESUMO
In recent years, monitoring of vitamin D levels and possible use of supplementation is gaining attention. Numerous studies showed low levels of vitamin D in winter months followed by improvement during summer. These changes are mostly dependent on the level of sun exposure, but also on geographical location, genetic factors, social-economic status, quality of nutrition and environmental pollution. In this observation we found significant decrease in vitamin D levels in populations exposed to extreme environmental pollution in area of central Europe. This region is known for extreme burden from microparticles originating in chemical industry, surface coal mining and cold-based power stations. Vitamin D levels in all patients was determined by ELISA. Using 540 patients in our department of clinical immunology and allergology we measured the levels of vitamin D in 2016 to 2021 period. In only 4 patients (0.74 %) we found vitamin D levels higher than 30 ng/ml. The curve of observed values does not reflect dependency on sun exposure and does not change during the year. We discuss the effect of environmental contaminants, lifestyle and economic and social factors. From our observations, we propose to directly supplement population with vitamin D, particularly children and seniors. From our observations, we propose to directly supplement population with vitamin D, particularly children and seniors.
Assuntos
Vitamina D , Vitaminas , Criança , Humanos , Poluição Ambiental , Ensaio de Imunoadsorção Enzimática , Europa (Continente)RESUMO
This review describes recent progress in the design and development of inhibitors of human carbonic anhydrase IX (CA IX) based on space-filling carborane and cobalt bis(dicarbollide) clusters. CA IX enzyme is known to play a crucial role in cancer cell proliferation and metastases. The new class of potent and selective CA IX inhibitors combines the structural motif of a bulky inorganic cluster with an alkylsulfamido or alkylsulfonamido anchor group for Zn2+ ion in the enzyme active site. Detailed structure-activity relationship (SAR) studies of a large series containing 50 compounds uncovered structural features of the cluster-containing inhibitors that are important for efficient and selective inhibition of CA IX activity. Preclinical evaluation of selected compounds revealed low toxicity, favorable pharmacokinetics and ability to reduce tumor growth. Cluster-containing inhibitors of CA IX can thus be considered as promising candidates for drug development and/or for combination therapy in boron neutron capture therapy (BNCT).
Assuntos
Compostos de Boro/química , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/química , Sítios de Ligação , Compostos de Boro/metabolismo , Compostos de Boro/uso terapêutico , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/metabolismo , Inibidores da Anidrase Carbônica/uso terapêutico , Humanos , Simulação de Dinâmica Molecular , Neoplasias/tratamento farmacológico , Compostos Organometálicos/química , Relação Estrutura-Atividade , Sulfonamidas/químicaRESUMO
Human carbonic anhydrase IX (CA IX), a protein specifically expressed on the surface of solid tumour cells, represents a validated target both for anticancer therapy and diagnostics. We recently identified sulfonamide dicarbaboranes as promising inhibitors of CA IX with favourable activities both in vitro and in vivo. To explain their selectivity and potency, we performed detailed X-ray structural analysis of their interactions within the active sites of CA IX and CA II. Series of compounds bearing various aliphatic linkers between the dicarbaborane cluster and sulfonamide group were examined. Preferential binding towards the hydrophobic part of the active site cavity was observed. Selectivity towards CA IX lies in the shape complementarity of the dicarbaborane cluster with a specific CA IX hydrophobic patch containing V131 residue. The bulky side chain of F131 residue in CA II alters the shape of the catalytic cavity, disrupting favourable interactions of the spherical dicarbaborane cluster.
Assuntos
Antineoplásicos/química , Compostos de Boro/química , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/química , Sulfonamidas/química , Sequência de Aminoácidos , Antígenos de Neoplasias/genética , Antineoplásicos/farmacologia , Anidrase Carbônica IX/genética , Inibidores da Anidrase Carbônica/farmacologia , Domínio Catalítico , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Relação Estrutura-Atividade , Sulfonamidas/farmacologiaRESUMO
The lack of specificity of traditional cytostatics and increasing resistance of cancer cells represent important challenges in cancer therapy. One of the characteristics of cancer cells is their intrinsic oxidative stress caused by higher metabolic activity, mitochondrial malfunction, and oncogene stimulation. This feature can be exploited in the pursuit of more selective cancer therapy, as there is increasing evidence that cancer cells are more sensitive to elevated concentrations of reactive oxygen species than normal cells. In this study, we demonstrate a new concept for cancer cell targeting by in situ production of radicals under physiological conditions. The biologically active radicals are produced in the milieu of cancer cells by enzymatic conversion from an inactive precursor, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt, by using miniature bioreactors represented by cell-sized microgels containing immobilized laccase. We utilize the pH-dependent activity of laccase to generate radicals only at a lower pH (5.7-6.1) that is characteristic of the tumor microenvironment. The composition of the microgels was optimized so as to allow sufficient substrate and radical diffusion, high enzyme activity, and stability under physiological conditions. The functionality of this system was evaluated on three cancer cell lines (HeLa, HT-29, and DLD1) and the cytotoxicity of in situ-produced radicals was successfully proven in all cases. These results demonstrate that cancer cell targeting by in situ-generated radicals using miniature enzymatic reactors may represent an alternative to traditional cytostatics. In particular, the pH-dependence of radical generation and their short-lived nature can ensure localized functionality in the tumor microenvironment and thereby reduce systemic side-effects.
Assuntos
Reatores Biológicos , Microgéis/química , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HT29 , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Lacase/metabolismo , Estresse Oxidativo , Tamanho da PartículaRESUMO
A water-soluble polymer cancerostatic actively targeted against cancer cells expressing a disialoganglioside antigen GD2 was designed, synthesized and characterized. A polymer conjugate of an antitumor drug doxorubicin with a N-(2-hydroxypropyl)methacrylamide-based copolymer was specifically targeted against GD2 antigen-positive tumor cells using a recombinant single chain fragment (scFv) of an anti-GD2 monoclonal antibody. The targeting protein ligand was attached to the polymer-drug conjugate either via a covalent bond between the amino groups of the protein using a traditional nonspecific aminolytic reaction with a reactive polymer precursor or via a noncovalent but highly specific interaction between bungarotoxin covalently linked to the polymer and the recombinant scFv modified with a C-terminal bungarotoxin-binding peptide. The GD2 antigen binding activity and GD2-specific cytotoxicity of the targeted noncovalent polymer-scFv complex proved to be superior to the covalent polymer-scFv conjugate.
Assuntos
Antineoplásicos/química , Gangliosídeos/imunologia , Nanoconjugados/química , Anticorpos de Cadeia Única/química , Células 3T3 , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Bungarotoxinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacologia , Camundongos , Ácidos Polimetacrílicos/química , Ligação Proteica , Anticorpos de Cadeia Única/imunologiaRESUMO
BACKGROUND AIMS: Clinical-grade chimeric antigenic receptor (CAR)19 T cells are routinely manufactured by lentiviral/retroviral (LV/RV) transduction of an anti-CD3/CD28 activated T cells, which are then propagated in a culture medium supplemented with interleukin (IL)-2. The use of LV/RVs for T-cell modification represents a manufacturing challenge due to the complexity of the transduction approach and the necessity of thorough quality control. METHODS: We present here a significantly improved protocol for CAR19 T-cell manufacture that is based on the electroporation of peripheral blood mononuclear cells with plasmid DNA encoding the piggyBac transposon/transposase vectors and their cultivation in the presence of cytokines IL-4, IL-7 and IL-21. RESULTS: We found that activation of the CAR receptor by either its cognate ligand (i.e., CD19 expressed on the surface of B cells) or anti-CAR antibody, followed by cultivation in the presence of cytokines IL-4 and IL-7, enables strong and highly selective expansion of functional CAR19 T cells, resulting in >90% CAR+ T cells. Addition of cytokine IL-21 to the mixture of IL-4 and IL-7 supported development of immature CAR19 T cells with central memory and stem cell memory phenotypes and expressing very low amounts of inhibitory receptors PD-1, LAG-3 and TIM-3. CONCLUSIONS: Our protocol provides a simple and cost-effective method for engineering high-quality T cells for adoptive therapies.
Assuntos
Técnicas de Cultura de Células/métodos , Elementos de DNA Transponíveis/genética , Interleucina-4/farmacologia , Interleucina-7/farmacologia , Interleucinas/farmacologia , Engenharia de Proteínas/métodos , Receptores de Antígenos Quiméricos/genética , Linfócitos T , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Células Cultivadas , Eletroporação , Vetores Genéticos , Células HEK293 , Humanos , Imunoterapia Adotiva/métodos , Lentivirus/genética , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Células PC-3 , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transdução Genética/métodosRESUMO
OBJECTIVE: Antibodies to cell surface central nervous system proteins help to diagnose conditions which often respond to immunotherapies. The assessment of antibody assays needs to reflect their clinical utility. We report the results of a multicentre study of aquaporin (AQP) 4 antibody (AQP4-Ab) assays in neuromyelitis optica spectrum disorders (NMOSD). METHODS: Coded samples from patients with neuromyelitis optica (NMO) or NMOSD (101) and controls (92) were tested at 15 European diagnostic centres using 21 assays including live (n=3) or fixed cell-based assays (n=10), flow cytometry (n=4), immunohistochemistry (n=3) and ELISA (n=1). RESULTS: Results of tests on 92 controls identified 12assays as highly specific (0-1 false-positive results). 32 samples from 50 (64%) NMO sera and 34 from 51 (67%) NMOSD sera were positive on at least two of the 12 highly specific assays, leaving 35 patients with seronegative NMO/spectrum disorder (SD). On the basis of a combination of clinical phenotype and the highly specific assays, 66 AQP4-Ab seropositive samples were used to establish the sensitivities (51.5-100%) of all 21 assays. The specificities (85.8-100%) were based on 92 control samples and 35 seronegative NMO/SD patient samples. CONCLUSIONS: The cell-based assays were most sensitive and specific overall, but immunohistochemistry or flow cytometry could be equally accurate in specialist centres. Since patients with AQP4-Ab negative NMO/SD require different management, the use of both appropriate control samples and defined seronegative NMOSD samples is essential to evaluate these assays in a clinically meaningful way. The process described here can be applied to the evaluation of other antibody assays in the newly evolving field of autoimmune neurology.
Assuntos
Aquaporina 4/sangue , Autoanticorpos/sangue , Neuromielite Óptica/sangue , Aquaporina 4/imunologia , Autoanticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imuno-Histoquímica/métodos , Neuromielite Óptica/imunologia , Sensibilidade e EspecificidadeRESUMO
The hyaluronate receptor CD44 plays role in cell adhesion and migration and is involved in tumor metastasis. The extracellular domain of CD44 comprises the hyaluronate-binding domain (HABD) and the membrane-proximal stem region; the short intracellular portion interacts with adaptor proteins and triggers signaling pathways. Binding of hyaluronate to CD44 HABD induces an allosteric conformational change, which results in CD44 shedding. A poorly characterized epitope in human CD44 HABD is recognized by the murine monoclonal antibody MEM-85, which cross-blocks hyaluronate binding to CD44 and also induces CD44 shedding. MEM-85 is of therapeutic interest, as it inhibits growth of lung cancer cells in murine models. In this work, we employed a combination of biophysical methods to determine the MEM-85 binding epitope in CD44 HABD and to provide detailed insight into the mechanism of MEM-85 action. In particular, we constructed a single-chain variable fragment (scFv) of MEM-85 as a tool for detailed characterization of the CD44 HABD-antibody complex and identified residues within CD44 HABD involved in the interaction with scFv MEM-85 by NMR spectroscopy and mutational analysis. In addition, we built a rigid body model of the CD44 HABD-scFv MEM-85 complex using a low-resolution structure obtained by small-angle X-ray scattering. The MEM-85 epitope is situated in the C-terminal part of CD44 HABD, rather than the hyaluronate-binding groove, and the binding of MEM-85 induces a structural reorganization similar to that induced by hyaluronate. Therefore, the mechanism of MEM-85 cross-blocking of hyaluronate binding is likely of an allosteric, relay-like nature.
Assuntos
Anticorpos Monoclonais/química , Receptores de Hialuronatos/química , Sítios de Ligação , Mapeamento de Epitopos , Humanos , Ácido Hialurônico/química , Células Jurkat , Modelos Moleculares , Mutação , Ressonância Magnética Nuclear Biomolecular , Estrutura Terciária de ProteínaRESUMO
The specificity of polymer conjugates based on N-(2-hydroxypropyl)methacrylamide (HPMA) bearing cytostatic drugs for cancer cells could be significantly increased by the incorporation of a suitable targeting ligand, such as a monoclonal antibody (mAb). However, direct binding of the protein to the polymer carrier could cause considerable problems, such as decreasing the binding capacity of mAb to its target. Here, we introduce a novel strategy of joining a targeting moiety to a polymeric conjugate with cytostatic drug. The scFv of B1 mAb (specific for BCL1 leukemia cells) was tagged with peptide K ((VAALKEK)4). Peptide E ((VAALEKE)4), which forms a stable coiled coil structure heterodimer with peptide K, was assembled with the HPMA copolymers bearing doxorubicin. Such targeted polymeric conjugates possess very selective and high binding activity toward BCL1 cells. Similarly, targeted polymeric conjugates exert approximately 100 times higher cytostatic activity toward BCL1 cells in comparison to nontargeted conjugates in vitro. At the same time, the conjugates have comparable and rather low cytostatic activity for 38C13 cells, which are used as a negative control, in vitro.
Assuntos
Acrilamidas/farmacologia , Materiais Biocompatíveis/farmacologia , Citostáticos/farmacologia , Leucemia/tratamento farmacológico , Polímeros/farmacologia , Acrilamidas/síntese química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Anticorpos Monoclonais/química , Materiais Biocompatíveis/síntese química , Linhagem Celular Tumoral , Proliferação de Células , Citostáticos/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Metacrilatos/química , Camundongos , Camundongos Endogâmicos BALB C , Polímeros/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismoRESUMO
The goal of this study is to summarize the results of the detection of Bordetella pertussis (BP) and Bordetella parapertussis (BPP) by a real-time polymerase chain reaction (RT-PCR) assay and serological methods. In 2008-2010, 73 patients of the Department of Clinical Immunology and Allergology of the Centre for Immunology and Microbiology, Public Health Institute in Ústí nad Labem were screened for pertussis. They were selected according to the WHO and ECDC criteria, i. e. they presented with a persistent cough lasting more than two weeks. Direct detection of BP and BPP DNA from nasopharyngeal wash specimens was performed using a RT PCR assay. The serological responses were evaluated by a direct agglutination test for the detection of total antibodies and by enzyme-linked immunosobent assay (ELISA) for the detection of IgG, IgA, and IgM antibodies against pertussis toxin. Forty-two patients were positive for BP and/or BPP, 19 of them by RT-PCR (group A) and 23 by serology (group B). Ten group A patients (52.6%) were also positive by serology. Our results show that pertussis needs to be a consideration in persistent cough. We believe that increased awareness of the medical community, along with improved laboratory tests will result in increased detection of pertussis that is still considered by many physicians as a childhood infection.
Assuntos
Anticorpos Antibacterianos/sangue , Bordetella parapertussis/isolamento & purificação , Bordetella pertussis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Coqueluche/diagnóstico , Testes de Aglutinação , Ensaio de Imunoadsorção Enzimática , HumanosRESUMO
Antibody-mediated targeting is an efficient strategy to enhance the specificity and selectivity of polymer nanomedicines towards the target site, typically a tumor. However, direct covalent coupling of an antibody with a polymer usually results in a partial damage of the antibody binding site accompanied with a compromised biological activity. Here, an original solution based on well-defined non-covalent interactions between tris-nitrilotriacetic acid (trisNTA) and hexahistidine (His-tag) groups, purposefully introduced to the structure of each macromolecule, is described. Specifically, trisNTA groups were attached along the chains of a hydrophilic statistical copolymer based on N-(2-hydroxypropyl)methacrylamide (HPMA), and at the end or along the chains of thermo-responsive di-block copolymers based on N-isopropylmethacrylamide (NIPMAM) and HPMA; His-tag was incorporated to the structure of a recombinant single chain fragment of an anti-GD2 monoclonal antibody (scFv-GD2). Static and dynamic light scattering analyses confirmed that mixing of polymer with scFv-GD2 led to the formation of polymer/scFv-GD2 complexes; those prepared from thermo-responsive polymers formed stable micelles at 37 °C. Flow cytometry and fluorescence microscopy clearly demonstrated antigen-specific binding of the prepared complexes to GD2 positive murine T-cell lymphoma cells EL-4 and human neuroblastoma cells UKF-NB3, while no interaction with GD2 negative murine fibroblast cells NIH-3T3 was observed. These non-covalent polymer protein complexes represent a new generation of highly specific actively targeted polymer therapeutics or diagnostics.
Assuntos
Neoplasias , Polímeros , Camundongos , Humanos , Animais , Polímeros/química , Ácido Nitrilotriacético , Sistemas de Liberação de Medicamentos/métodos , Proteínas RecombinantesRESUMO
BACKGROUND AND AIMS: Elderly nursing home residents are especially prone to a severe course of SARS-CoV-2 infection. In this study, we aimed to investigate the complex immune response after vaccination depending on the convalescence status and vaccine. METHODS: Sampling took place in September-October 2021. IgG antibodies against spike protein and nucleocapsid protein, the titer of virus neutralization antibodies against delta and (on a subset of patients) omicron, and cellular immunity (interferon-gamma release assay) were tested in nursing home residents vaccinated with Pfizer, Moderna (both 30-31 weeks after the completion of vaccination), or AstraZeneca (23 weeks) vaccines. The prevalence with 95% confidence intervals (CI) was evaluated in Stata version 17. RESULTS: 95.2% (95% CI: 92.5-97.1%) of the 375 participants had positive results of anti-S IgG, 92.8% (95% CI: 89.7-95.2%) were positive in virus neutralization assay against delta, and 89.0% (95% CI: 84.5-92.5%) in the interferon-gamma-releasing assay detecting cellular immunity. Results of the virus neutralization assay against omicron correlated with those against delta but the neutralization capacity was reduced by about half. As expected, the worst results were found for the AstraZeneca vaccine, although the vaccination-to-test period was the shortest for this vaccine. All immune parameters were significantly higher in convalescent residents than in naive residents after vaccination. No case of COVID-19 occurred during the vaccination-to-test period. CONCLUSIONS: A high immune response, especially among vaccinated convalescents (i.e., residents with hybrid immunity), was found in elderly nursing home residents 5-7 months after vaccination against SARS-CoV-2. In view of this, it appears that such residents are much better protected from COVID-19 than those who are only vaccinated and the matter of individual approach to the booster dose in such individuals should be further discussed.
Assuntos
COVID-19 , Vacinas , Idoso , COVID-19/epidemiologia , COVID-19/prevenção & controle , República Tcheca/epidemiologia , Humanos , Imunidade , Imunoglobulina G , Casas de Saúde , SARS-CoV-2 , VacinaçãoRESUMO
Precancerous lesions of human cervix uteri have a tendency for regression or progression. In cervical intraepithelial neoplasia grade 2 (CINII) case there is an uncertainty if a lesion will progress or regress. The carbonic anhydrase IX (CAIX) enzyme is overexpressed in cervical cancer which is more sensitive to radiotherapy. CAIX is associated with poor prognosis in solid hypoxic tumors. The aim of this study was to determine factors related to elevated soluble CAIX (s-CAIX) in high-grade intraepithelial lesion (HSIL) cases. METHODS: Patients diagnosed with HSIL (N = 77) were included into the research group whereas without HSIL (N = 72)-the control group. Concentration of the soluble CAIX (s-CAIX) in plasma was determined by the DIANA ligand-antibody-based method. C. trachomatis was detected from cervical samples by PCR. Primary outcomes were risk factors elevating s-CAIX level in HSIL group. Non-parametric statistical analysis methods were used to calculate correlations. RESULTS: The s-CAIX level in patients with HSIL was elevated among older participants (rs = 0.27, p = 0.04) and with C. trachomatis infection (p = 0.028). Among heavy smokers with HSIL, the concentration of s-CAIX was higher in older women (rs = 0.52, p = 0.005), but was not related to the age of heavy smokers' controls (τ = 0.18 p = 0.40). CONCLUSION: The concentration of s-CAIX was higher among older, heavy smoking and diagnosed with C. trachomatis patients. All these factors increased the risk for HSIL progression.
Assuntos
Antígenos de Neoplasias/metabolismo , Anidrase Carbônica IX/metabolismo , Anidrases Carbônicas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Idoso , Feminino , HumanosRESUMO
We have designed, synthesized, and characterized peptides containing four repeats of the sequences VAALEKE (peptide E) or VAALKEK (peptide K). While the peptides alone adopt in aqueous solutions a random coil conformation, their equimolar mixture forms heterodimeric coiled coils as confirmed by CD spectroscopy. 5-Azidopentanoic acid was connected to the N-terminus of peptide E via a short poly(ethylene glycol) spacer. The terminal azide group enabled conjugation of the peptide with a synthetic drug carrier based on the N-(2-hydroxypropyl)methacrylamide copolymer containing propargyl groups using "click" chemistry. When incorporated into the polymer drug carrier, peptide E formed a stable noncovalent complex with peptide K belonging to a recombinant single-chain fragment (scFv) of the M75 antibody. The complex thereby mediates a noncovalent linkage between the polymer drug carrier and the protein. The recombinant scFv antibody fragment was selected as a targeting ligand against carbonic anhydrase IX-a marker overexpressed by tumor cells of various human carcinomas. The antigen binding affinity of the polymer-scFv complex was confirmed by ELISA. This approach offers a well-defined, specific, and nondestructive universal method for the preparation of protein (antibody)-targeted polymer drug and gene carriers designed for cell-specific delivery.
Assuntos
Acrilamidas/química , Anticorpos Monoclonais/química , Química Click/métodos , Portadores de Fármacos/síntese química , Imunoconjugados/química , Oligopeptídeos/síntese química , Proteínas Recombinantes/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Anidrase Carbônica IX , Anidrases Carbônicas/imunologia , Anidrases Carbônicas/metabolismo , Carcinoma/tratamento farmacológico , Carcinoma/enzimologia , Carcinoma/imunologia , Carcinoma/patologia , Dicroísmo Circular , Clonagem Molecular , Dimerização , Portadores de Fármacos/farmacologia , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Humanos , Imunoconjugados/imunologia , Imunoconjugados/farmacologia , Conformação Molecular , Oligopeptídeos/imunologia , Oligopeptídeos/farmacologia , Plasmídeos , Polietilenoglicóis/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Transformação BacterianaRESUMO
Targeted cancer immunotherapy is a promising tool for restoring immune surveillance and eradicating cancer cells. Hydrophilic polymers modified with coiled coil peptide tags can be used as universal carriers designed for cell-specific delivery of such biologically active proteins. Here, we describe the preparation of pHPMA-based copolymer conjugated with immunologically active protein B7-H6 via complementary coiled coil VAALEKE (peptide E) and VAALKEK (peptide K) sequences. Receptor B7-H6 was described as a binding partner of NKp30, and its expression has been proven for various tumor cell lines. The binding of B7-H6 to NKp30 activates NK cells and results in Fas ligand or granzyme-mediated apoptosis of target tumor cells. In this work, we optimized the expression of coiled coil tagged B7-H6, its ability to bind activating receptor NKp30 has been confirmed by isothermal titration calorimetry, and the binding stoichiometry of prepared chimeric biopolymer has been characterized by analytical ultracentrifugation. Furthermore, this coiled coil B7-H6-loaded polymer conjugate activates NK cells in vitro and, in combination with coiled coil scFv, enables their targeting towards a model tumor cell line. Prepared chimeric biopolymer represents a promising precursor for targeted cancer immunotherapy by activating the cytotoxic activity of natural killer cells.
RESUMO
Invited for this month's cover is a collaboration from three institutes from the Czech Academy of Sciences: Institute of Inorganic Chemistry, Institute of Organic Chemistry and Biochemistry, and Institute of Molecular Genetics, and the University of Pardubice. The cover picture shows a family of potent and selective CA IX inhibitors that combines the structural motif of a bulky inorganic cobalt bis(dicarbollide) polyhedral ion with a propylsulfonamido anchor group. Read the full text of the article at 10.1002/cplu.202000574.
Assuntos
Inibidores da Anidrase Carbônica , Neoplasias , Anidrase Carbônica IX , Cobalto , HumanosRESUMO
Carbonic anhydrase IX (CAIX) is an enzyme expressed on the surface of cells in hypoxic tumors. It plays a role in regulation of tumor pH and promotes thus tumor cell survival and occurrence of metastases. Here, derivatives of the cobalt bis(dicarbollide)(1-) anion are reported that are based on substitution at the carbon sites of the polyhedra by two alkylsulfonamide groups differing in the length of the aliphatic connector (from C1 to C4, n=1-4), which were prepared by cobalt insertion into the 7-sulfonamidoalkyl-7,8-dicarba-nido-undecaborate ions. Pure meso- and rac-diastereoisomeric forms were isolated. The series is complemented with monosubstituted species (n=2). Synthesis by a direct method furnished similar derivatives (n=2, 3), which are chlorinated at the B(8,8') boron sites. All compounds inhibited CAIX with subnanomolar inhibition constants and showed high selectivity for CAIX. The best inhibitory properties were observed for the compound with n= 3 and two substituents present in rac-arrangement with Ki =20â pM and a selectivity index of 668. X-ray crystallography was used to study interactions of these compounds with the active site of CAIX on the structural level.
Assuntos
Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/química , Cobalto/química , Complexos de Coordenação/química , Sulfonamidas/química , Sítios de Ligação , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/metabolismo , Inibidores da Anidrase Carbônica/uso terapêutico , Domínio Catalítico , Complexos de Coordenação/metabolismo , Complexos de Coordenação/uso terapêutico , Cristalografia por Raios X , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologiaRESUMO
The DNA-linked inhibitor antibody assay (DIANA) has been recently validated for ultrasensitive enzyme detection and for quantitative evaluation of enzyme inhibitor potency. Here we present its adaptation for high-throughput screening of human carbonic anhydrase IX (CAIX), a promising drug and diagnostic target. We tested DIANA's performance by screening a unique compound collection of 2816 compounds consisting of lead-like small molecules synthesized at the Institute of Organic Chemistry and Biochemistry (IOCB) Prague ("IOCB library"). Additionally, to test the robustness of the assay and its potential for upscaling, we screened a pooled version of the IOCB library. The results from the pooled screening were in agreement with the initial nonpooled screen with no lost hits and no false positives, which shows DIANA's potential to screen more than 100,000 compounds per day.All DIANA screens showed a high signal-to-noise ratio with a Z' factor of >0.89. The DIANA screen identified 13 compounds with Ki values equal to or better than 10 µM. All retested hits were active also in an orthogonal enzymatic assay showing zero false positives. However, further biophysical validation of identified hits revealed that the inhibition activity of several hits was caused by a single highly potent CAIX inhibitor, being present as a minor impurity. This finding eventually led us to the identification of three novel CAIX inhibitors from the screen. We confirmed the validity of these compounds by elucidating their mode of binding into the CAIX active site by x-ray crystallography.
Assuntos
Bioensaio , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/isolamento & purificação , Ensaios de Triagem em Larga Escala , Antígenos de Neoplasias/genética , Anidrase Carbônica IX/genética , Inibidores da Anidrase Carbônica/uso terapêutico , Domínio Catalítico/efeitos dos fármacos , DNA/efeitos dos fármacos , DNA/genética , Humanos , Simulação de Acoplamento Molecular , Preparações FarmacêuticasRESUMO
Carbonic anhydrase IX (CA IX) is a transmembrane enzyme overexpressed in hypoxic tumors, where it plays an important role in tumor progression. Specific CA IX inhibitors potentially could serve as anti-cancer drugs. We designed a series of sulfonamide inhibitors containing carborane clusters based on prior structural knowledge of carborane binding into the enzyme active site. Two types of carborane clusters, 12-vertex dicarba-closo-dodecaborane and 11-vertex 7,8-dicarba-nido-undecaborate (dicarbollide), were connected to a sulfonamide moiety via aliphatic linkers of varying lengths (1-4 carbon atoms; n = 1-4). In vitro testing of CA inhibitory potencies revealed that the optimal linker length for selective inhibition of CA IX was n = 3. A 1-sulfamidopropyl-1,2-dicarba-closo-dodecaborane (3) emerged as the strongest CA IX inhibitor from this series, with a Ki value of 0.5 nM and roughly 1230-fold selectivity towards CA IX over CA II. X-ray studies of 3 yielded structural insights into their binding modes within the CA IX active site. Compound 3 exhibited moderate cytotoxicity against cancer cell lines and primary cell lines in 2D cultures. Cytotoxicity towards multicellular spheroids was also observed. Moreover, 3 significantly lowered the amount of CA IX on the cell surface both in 2D cultures and spheroids and facilitated penetration of doxorubicin. Although 3 had only a moderate effect on tumor size in mice, we observed favorable ADME properties and pharmacokinetics in mice, and preferential presence in brain over serum.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Sulfonamidas/farmacologia , Animais , Antígenos de Neoplasias/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cães , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/químicaRESUMO
Atopy is a predisposition to hyperproduction of immunoglobulin E (IgE) against common environmental allergens. It is often associated with development of allergic diseases such as asthma, rhinitis, and dermatitis. Production of IgE is influenced by genetic and environmental factors. In spite of progress in the study of heredity of atopy, the genetic mechanisms of IgE regulation have not yet been completely elucidated. The analysis of complex traits can benefit considerably from integration of human and mouse genetics. Previously, we mapped a mouse IgE-controlling locus Lmr9 on chromosome 4 to a segment of <9 Mb. In this study, we tested levels of total IgE and 25 specific IgEs against inhalant and food allergens in 67 Czech atopic families. In the position homologous to Lmr9 on chromosome 8q12 marked by D8S285, we demonstrated a novel human IgE-controlling locus exhibiting suggestive linkage to composite inhalant allergic sensitization (limit of detection, LOD = 2.11, P = 0.0009) and to nine specific IgEs, with maximum LOD (LOD = 2.42, P = 0.0004) to plantain. We also tested 16 markers at previously reported chromosomal regions of atopy. Linkage to plant allergens exceeding the LOD > 2.0 was detected at 5q33 (D5S1507, LOD = 2.11, P = 0.0009) and 13q14 (D13S165, LOD = 2.74, P = 0.0002). The significant association with plant allergens (quantitative and discrete traits) was found at 7p14 (D7S2250, corrected P = 0.026) and 12q13 (D12S1298, corrected P = 0.043). Thus, the finding of linkage on chromosome 8q12 shows precision and predictive power of mouse models in the investigation of complex traits in humans. Our results also confirm the role of loci at 5q33, 7p14, 12q14, and 13q13 in control of IgE.