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1.
Virol J ; 19(1): 153, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163265

RESUMO

BACKGROUND: JC polyomavirus (JCPyV) is known to induce solid tumors such as astrocytomas, glioblastomas, and neuroblastomas in experimental animals, and recent studies have shown that the virus may be correlated with carcinogenesis. This study aimed to evaluate the impact of JCPyV on the progression of papillary thyroid cancer (PTC). METHODS: A total of 1057 samples, including 645 paraffin-embedded PTC biopsy samples (PEBS) and 412 fresh biopsy samples (FBS), and 1057 adjacent non-cancerous samples were evaluated for the presence of JCPyV DNA and RNA. RESULTS: We observed that 10.8% (114/1057) samples, including 17.5% (72/412) FBS and 6.5% (42/645) PEBS were positive for the JCPyV DNA. Among the JCPyV-positive samples, the mean JCPyV copy number was lower in patients with PEBS (0.3 × 10-4 ± 0.1 × 10-4 copies/cell) compared to FBS (1.8 × 10-1 ± 0.4 × 10-1 copies/cell) and non-PTC normal samples (0.2 × 10-5 ± 0.01 × 10-5 copies/cell), with a statistically significant difference (P < 0.001). The LT-Ag RNA expression was lower in PEBS than in FBS, while no VP1 gene transcript expression was found. CONCLUSIONS: Although our results confirmed the presence of JCPyV in some Iranian patients with PTC, more research is needed to verify these results.


Assuntos
Vírus JC , Infecções por Polyomavirus , Neoplasias da Glândula Tireoide , Humanos , Irã (Geográfico) , Vírus JC/genética , RNA , Câncer Papilífero da Tireoide
2.
Gene ; 676: 95-100, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30017737

RESUMO

The tripartite motif (TRIM)-5 and TRIM22 are involved in innate immune response and show anti-viral activities. The current study aimed at evaluating the association of TRIM5 and TRIM22 polymorphisms with treatment outcomes in patients with chronic hepatitis C virus (CHC). TRIM5 rs3824949 and TRIM22 polymorphisms (rs7113258, rs7935564, and rs1063303) were genotyped using TaqMan polymerase chain reaction (PCR) assay in 425 treatment-naïve CHC patients. Rapid virological response (RVR), early virological response (EVR), and sustained virological response (SVR) were found in 54.1%, 74.8%, and 67.1% of the patients, respectively. RVR and SVR were associated with TRIM5 rs3824949 (GG), TRIM22 rs1063303 (GC), and TRIM22 rs7113258 (AA), while there was a relationship between TRIM5 rs3824949 (GG) and EVR. TRIM5 and TRIM22 single nucleotide polymorphisms (SNPs) were strongly associated with increased odds of RVR, EVR, and SVR after an interferon-based therapy in patients with CHC.


Assuntos
Antivirais/uso terapêutico , Proteínas de Transporte/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Antígenos de Histocompatibilidade Menor/genética , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/genética , Proteínas com Motivo Tripartido/genética , Adulto , Fatores de Restrição Antivirais , Feminino , Hepatite C Crônica/genética , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resposta Viral Sustentada , Resultado do Tratamento , Ubiquitina-Proteína Ligases
3.
Microb Pathog ; 121: 310-317, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29859290

RESUMO

The emergence of extensively drug-resistant (XDR) Acinetobacter baumannii strains and the limited number of efficacious antibiotics demonstrate an urgent need to develop novel agents to treat infections caused by this dangerous pathogen. To find antimicrobial peptides against A. baumannii growing either in planktonic or in biofilm mode, biopanning was carried out with a peptide library on five XDR A. baumannii strains grown in the medium containing human blood (blood biopanning) and biofilms formed by these strains (biofilm biopanning). Two groups of peptides were identified, among which two peptides N10 (from blood biopanning) and NB2 (from biofilm biopanning) were selected and synthesized for more assessments. The selected peptides showed significant binding to A. baumannii rather than to the human cell line Caco-2. Both peptides were effective against A. baumannii and showed antibacterial activities (minimum inhibitory concentration (MIC) 500 µg/ml). In the biofilm inhibition assay, NB2 reduced biofilm more efficiently (75%) than N10 (50%). The combination of the two peptides could function better than each peptide alone to prevent biofilm formation by A. baumannii. Supplementation of conventional therapy with a mixture of peptides targeting A. baumannii or using peptides to deliver antibiotics specifically to the site of infection may be promising to control A. baumannii-related diseases.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/fisiologia , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Peptídeos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Células CACO-2 , Humanos , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA
4.
Infect Genet Evol ; 62: 296-303, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29715527

RESUMO

The cluster of differentiation 81 (CD81) and scavenger receptor class B member 1 (SCARB1) plays an important role in the entry of hepatitis C virus (HCV). We assessed the correlation of five single nucleotide polymorphisms (SNPs) of CD81 (rs800136, rs2651842, rs2522012, rs800146, and rs708564) and SCARB1 rs10846744 polymorphisms with treatment responses in 395 treatment-naïve patients with chronic HCV (CHC) genotype 1 treated with pegylated interferon-α and ribavirin (pegIFN-α/RBV). The frequency of rapid virologic response (RVR), complete early virologic response (cEVR) and sustained virologic response (SVR) were 57.2%, 55.2%, and 58.2%, respectively. RVR, cEVR, and SVR were significantly associated with CD81 rs800136 (CC), CD81 rs2651842 (AA), CD81 rs708564 (TT), and SCARB1 rs10846744 (CC). High rates of RVR, cEVR, and SVR were reported for the CD81 rs800136 (CC), CD81 rs2651842 (AA), and CD81 rs708564 (TT) genotypes when correlated with higher levels of low-density lipoprotein (LDL) and lower levels of high-density lipoprotein (HDL) as well as lower levels of HDL and LDL in the SCARB1 rs10846744 (CC) genotype. In addition, patients with GG genotype had higher fasting blood glucose (FBS) level than those with CC genotype. In conclusion, CD81 and SCARB1 SNPs may serve as powerful predictor factors for treatment responses in CHC patients, and this effect is correlated with serum lipoprotein and FBS levels.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/virologia , Receptores Depuradores Classe B/genética , Tetraspanina 28/genética , Adulto , Feminino , Regulação da Expressão Gênica/imunologia , Predisposição Genética para Doença , Genótipo , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/imunologia , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Carga Viral
5.
Sci Rep ; 8(1): 5036, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29568043

RESUMO

A novel blood-borne virus called the human hepegivirus 1 (HHpgV-1) was recently discovered in hemophilia patients. The present study aimed to investigate the presence of HHpgV-1 in hemophilia patients. A total of 436 serum samples were investigated for the presence of hepatitis C virus (HCV), human pegivirus-1 (HPgV-1), torque teno virus (TTV), and HHpgV-1. Out of the 436 patients, 163 (37.4%), 19 (4.4%), 76 (17.4%), and four (0.9%) patients were positive for HCV, HPgV-1, TTV, and HHpgV-1, respectively. HHpgV-1 patients had a mean viral load of 4.9 ± 0.3 log RNA copies/mL and were co-infected with HCV-1a, HPgV-1, and TTV. Moreover, three HHpgV-1-positive patients exhibited stage F0 liver fibrosis. HCV viral load in HHpgV-1-positive patients was lower than those of HHpgV-1-negative patients. Results also revealed that co-infection of HHpgV-1 with HPgV-1 and HCV may play a protective role in patients with chronic HCV. In conclusion, we detected a low frequency of HHpgV-1 infection in hemophilia patients, and results suggested that HHpgV-1 infection was correlated with the presence of other blood-borne viruses and is likely to also correlate with low HCV viral load and reduced severity of liver disease. Additional studies are required to further investigate the clinical importance of HHpgV-1.


Assuntos
Patógenos Transmitidos pelo Sangue/isolamento & purificação , Coinfecção/epidemiologia , Infecções por Flaviviridae/epidemiologia , Flaviviridae/isolamento & purificação , Hemofilia A/terapia , Hepatite C/epidemiologia , Adulto , Transfusão de Sangue , Coinfecção/sangue , Coinfecção/diagnóstico , Coinfecção/transmissão , Feminino , Infecções por Flaviviridae/sangue , Infecções por Flaviviridae/diagnóstico , Infecções por Flaviviridae/transmissão , Hemofilia A/sangue , Hepatite C/sangue , Hepatite C/diagnóstico , Hepatite C/transmissão , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Prevalência , Carga Viral , Adulto Jovem
6.
Tuberculosis (Edinb) ; 107: 31-37, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29050769

RESUMO

Antimicrobial drug resistance creates major problems in the control of tuberculosis (TB). Beijing and Haarlem genotypes of Mycobacterium tuberculosis are the prevalent genotypes responsible for multidrug resistant (MDR) TB worldwide. The aim of this study was to conduct a systematic review using meta-analysis to indicate the prevalence of Beijing and Haarlem genotypes among MDR-TB cases in Iran. Data sources of current study were 311 original articles (2006-2016) that were searched in several databases including Medline, Scopus, Embase, Cochrane library, and Iranian databases. Sixteen articles were selected for the prevalence of Beijing and Haarlem families among MDR-TB strains. Data were evaluated using meta-analysis and random effects models with the Meta-Analysis Software package Version 2.2 (Biostat, Englewood, NJ). Final investigation indicated 856 MDR samples in the 16 articles. Overall, the prevalence of Beijing and Haarlem genotypes among MDR-TB isolates in Iran was estimated to be 19.3% (95% CI, 13.1-27.5) and 18.7% (95% CI, 11.9-28.3) respectively. The studies conducted in northern Iran showing a significant association between Haarlem genotype and MDR is of particular concern. Certain refugee migration flows make this genotype of particular epidemiological and clinical concern because of its potential ability to endanger TB control programs in Iran.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/virologia , Antituberculosos/uso terapêutico , China , Genótipo , Humanos , Irã (Geográfico) , Epidemiologia Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade , Prevalência , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
7.
Gene ; 630: 28-34, 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-28827115

RESUMO

The scavenger receptor type B class I (SCARBI) is known to be involved in the entry of hepatitis C virus (HCV) into the host, while interleukin-15 (IL15) is an important cytokine in both the innate and acquired immune responses against HCV infection. We investigated the association of IL15 rs10833 or SCARB1 rs10846744 polymorphisms with treatment responses in patients with chronic HCV (CHC). SCARB1 rs10846744 and IL15 rs10833 were identified in 365 treatment-naïve CHC patients through genotyping by TaqMan® Real-Time PCR and PCR-restriction fragment length polymorphism (RFLP), respectively. Of these 365 CHC treatment-naïve patients, rapid virological response (RVR), complete early virological response (cEVR), and sustained virological response (SVR) were observed in 53.2%, 76.4%, and 66.0% of the patients, respectively. Multivariate logistic regression analysis revealed that RVR was associated with sex (P=0.016), aspartate aminotransferase (AST) (P=0.026), IL15 rs10833 (AA) genotype (P<0.001), and SCARB1 rs10846744 (CC) genotype (P<0.001), while there was a relationship between alanine aminotransferase (ALT) (P=0.013) and IL15 rs10833 (AA) genotype (P<0.001) with cEVR. Age (<40years) (P=0.001), AST (P=0.029), ALP (P=0.028), HCV genotypes (P=0.005), HCV viral load (P=0.026), IL15 rs10833 (AA) genotype (P<0.001), and SCARB1 rs10846744 (CC) genotype (P=0.001) were strongly associated with SVR. In conclusion, the SCARB1 rs10846744 (CC) and IL15 rs10833 (AA) genotypes can be considered as powerful predictors of treatment responses in CHC patients treated with an interferon-based therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/genética , Interleucina-15/genética , Polimorfismo de Nucleotídeo Único , Receptores Depuradores Classe B/genética , Resposta Viral Sustentada , Adulto , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico
8.
Infect Genet Evol ; 54: 330-337, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28739427

RESUMO

Single nucleotide polymorphisms (SNPs) near the interleukin-28B (IL28B), interferon lambda 4 (IFNL4) and the human leukocyte antigen (HLA) gene are associated with treatment responses in patients with chronic hepatitis C (CHC) virus infection treated with pegylated interferon-α and ribavirin (pegIFN-α/RBV). We compared the role of IL28B SNPs (rs12979860, rs12980275, and rs8099917), IFNL4 ss469415590 and HLA rs4273729 with treatment outcomes in patients with CHC virus. A total of 520 Iranian patients with CHC infection were enrolled. SNPs in IL28B, IFNL4 ss469415590 and HLA rs4273729 were genotyped by PCR-restriction fragment length polymorphism, TaqMan® Real-Time PCR and direct sequence. Out of 520 CHC treatment-naive patients, 42.9% were infected with HCV-1a, 15.4% with HCV-1b, 9.8% with HCV-2, and 31.9% with HCV-3a. Rapid virologic response (RVR), complete early virologic response (cEVR), and sustained virologic response (SVR) were 53.3%, 73.8%, and 66.7%, respectively. Multivariate logistic regression analysis showed that IL28B rs12980275 and IFNL4 ss469415590 in all HCV genotypes were associated with RVR. In addition, IL28B rs12979860 and RVR in all HCV genotypes and IL28B rs12980275, IFNL4 ss469415590, and HLA rs4273729 in HCV subtypes 1a, 1b, and 3a correlated with cEVR. In patient's achieving-SVR, IL28B rs12980275, and RVR in all HCV genotypes and IL28B rs12979860, IFNL4 ss469415590, and HLA rs4273729 in HCV subtypes 1a, 1b, and 3a were the powerful predictor factors. As the first report of its kind published in Iran, we indicated that beside IL28B SNPs and HLA rs4273729, IFNL4 ss469415590 was a powerful predictor factor for RVR, cEVR and SVR. Genotyping these SNPs may be a helpful priority in the treatment of patients with HCV infection, especially in countries where access to triple or double therapy with a viral protease inhibitor is limited.


Assuntos
Antígenos HLA/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interleucinas/genética , Variantes Farmacogenômicos , Ribavirina/uso terapêutico , Adulto , Antivirais/farmacologia , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/farmacologia , Interferons , Irã (Geográfico) , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Ribavirina/farmacologia , Resultado do Tratamento , Carga Viral
9.
Biologicals ; 49: 33-38, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28716625

RESUMO

This study aimed to evaluate the frequency of resistance to first- and second-line drugs using phenotypic and genotypic methods and its correlation with resistance-linked mutations in Mycobacterium tuberculosis (M. tb) isolated in Iran. Three different methods, including the indirect proportion method(PM), direct and indirect nitrate reductase assay(NRA), and direct sequencing were used to assess drug resistance. In this study, sensitivity, specificity, agreement, costs, and turnaround time of these methods were compared in 395 smear positive isolates. Compared to the PM, the NRA and the direct sequencing methods demonstrated higher specificity, sensitivity, and agreement for detection of all anti-tuberculosis drugs. The NRA had a short turnaround time and was more cost-effective than the other methods. Mutations in codon 531 in rpoB, 315 in katG, 18 in rpsL, and 306 in embB were associated with high-level resistance to the first-line drugs, and mutations in codon 94 in gyrA, and A1401G in rrs were correlated with resistance to the second-line drugs. We found that the NRA is a highly sensitive, specific, inexpensive, and rapid test with strong potential to be a useful and interesting alternative tool, particularly in low-income countries. In addition, these molecular data will be helpful for developing new molecular methods for detecting first- and second-line drug-resistant M. tb.


Assuntos
Proteínas de Bactérias , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana/métodos , Mutação , Mycobacterium tuberculosis , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Análise Mutacional de DNA/métodos , DNA Bacteriano/metabolismo , Feminino , Humanos , Masculino , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética
10.
Microb Pathog ; 108: 21-26, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28455138

RESUMO

Several risk factors have been linked to lung cancer (LC). Nevertheless, a viral etiology has been mentioned for a subset of patients developing LC. The aim of this study was to evaluate the effect of Merkel cell polyomavirus (MCPyV) on developing non-small cell lung cancer (NSCLCs). In total, 96 paraffin-embedded NSCLC biopsies and 96 adjacent non-LC normal specimens were analyzed by quantitative real-time polymerase chain reaction (PCR) for the existence of the MCPyV DNA and the expressions of RNA transcripts. Among the 96 enrolled participants, 42 patients were adenocarcinomas (ADs) and 54 patients were squamous cell carcinoma (SCC). Of the 42 ADs, MCPyV DNA was determined in 15 (35.7%) samples and of the 54 SCC, MCPyV DNA was detected in 22 (40.7%) samples. Only one non-cancerous sample in SCC subjects was positive for MCPyV LT-Ag DNA load (0.216 × 10-3). In MCPyV-positive subjects, the median MCPyV copy number was higher in the patients with ADs (0.016 × 10-3 copies/cell) compared to SCCs (0.005 × 10-3 copies/cell); but this difference was not statistically significant (P = 0.913). In the seven stages of LC, the MCPyV LT-Ag was quantified in stage IV (0.204 × 10-3 copies/cell) more than in other stages. There was statistically significant difference between stages of cancer and MCPyV LT-Ag DNA load (P = 0.002). These results revealed for the first time the presence of MCPyV in a subset of patients with NSCLCs in Iran. Further studies should be carried out to clarify the role of MCPyV in lung carcinogenesis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/virologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/virologia , Poliomavírus das Células de Merkel/patogenicidade , Infecções Tumorais por Vírus/complicações , Adenocarcinoma/diagnóstico , Adenocarcinoma/epidemiologia , Adenocarcinoma/virologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/virologia , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Neoplasias Pulmonares/diagnóstico , Masculino , Poliomavírus das Células de Merkel/genética , Pessoa de Meia-Idade , Prevalência , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Fumar , Infecções Tumorais por Vírus/genética , Infecções Tumorais por Vírus/virologia , Carga Viral
11.
Arch Virol ; 162(1): 181-189, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27714501

RESUMO

Single-nucleotide polymorphisms (SNPs) in the Interleukin-28B (IL28B) gene and rs4273729 in the human leukocyte antigen (HLA) gene in chronic hepatitis C (CHC) virus infection are important for predicting treatment outcome. In this study, the distribution of IL28B SNPs (rs12979860 and rs12980275) and HLA rs4273729 in rapid virologic response (RVR), complete early virologic response (cEVR) and sustained virologic response (SVR) in HCV Iranian patients with CHC virus infection was assessed. IL28B genotyping and rs4273729 were performed using the amplification refractory mutation system (ARMS)-PCR and direct sequencing in 190 CHC virus infections, respectively. RVR, cEVR, and SVR were 53.2 %, 78.9 %, and 65.8 %, respectively. Multivariate regression analysis demonstrated that the responses significantly predicted SVR in patients with age <40 years (p = 0.008), HCV genotypes (p = 0.032), IL28B rs12979860 CC genotype (p < 0.001), rs12980275 AA genotype (p < 0.001), rs4273729 GG genotype (p < 0.001), RVR (p < 0.001) and cEVR (p = 0.024). Three critical predictor factors based on RVR response were rs12979860 CC genotype (p = 0.033), rs12980275 AA genotype (p < 0.001) and rs4273729 GG genotype (p < 0.001), while rs12980275 AA (p = 0.003) and rs4273729 GG genotypes (p < 0.001) predicted cEVR. For the first time in Iran, these results revealed that the rs12980275 and HLA rs4273729 are important for the treatment of CHC infection. These findings may help predict responses to CHC infection treatment and reduce the cost and side effects of therapy.


Assuntos
Antivirais/uso terapêutico , Antígenos HLA/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Resposta Viral Sustentada , Adulto , Estudos Transversais , Feminino , Técnicas de Genotipagem , Hepatite C Crônica/genética , Humanos , Interferon-alfa/uso terapêutico , Interferons , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Prognóstico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Fatores de Tempo , Adulto Jovem
12.
Toxicon ; 124: 83-93, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27845058

RESUMO

The venom of the Hemiscorpius lepturus scorpion contains mixtures of bioactive compounds that disturb biochemical and physiological functions of the victims. Hemiscorpius lepturus envenomation is recognized as a serious health concern in tropical regions. So far, there is no preventive procedure, and the main focus is on treatment of victims with an antiserum purified from hyper-immunized horses. Although antisera can neutralize the venom, they, in some cases, lead to anaphylactic shock and even death. Selection of peptides mimicking antigenic and immunogenic epitopes of toxins from random peptide libraries is a novel approach for the development of recombinant toxins and poly-epitopic vaccine. To achieve this aim, a phage display peptide library and three rounds of biopanning were performed on immobilized antibodies (IgGs) purified from the sera of hyper-immunized horses. The results show that the highest binding of the phage to immobilized horse antibodies occurred in the third round of biopanning. Over 125 individual clones carrying mimotopes of Hemiscorpius lepturus toxins were selected and subjected for sequencing. The sequencing results identified unique peptides mimicking the antigenic and immunogenic epitopes of Hemiscorpius lepturus toxins. The results of this study provide a basis for further studies and the development of a putative epitopic vaccine and a recombinant toxin.


Assuntos
Bacteriófagos/genética , Epitopos/imunologia , Venenos de Escorpião/imunologia , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Escorpiões , Homologia de Sequência de Aminoácidos
13.
Biochim Biophys Acta ; 1840(1): 378-86, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24076235

RESUMO

BACKGROUND: Adoptive cell therapy with engineered T cells expressing chimeric antigen receptors (CARs) originated from antibodies is a promising strategy in cancer immunotherapy. Several unsuccessful trials, however, highlight the need for alternative conventional binding domains and the better combination of costimulatory endodomains for CAR construction to improve the effector functions of the engineered T cells. Camelid single-domain antibodies (VHHs), which are the smallest single domain antibodies, can endow great targeting ability to CAR-engineered T cells. METHODS: We have developed a method to generate genetically engineered Jurkat T cells armed with a CAR comprising the anti-HER2 VHH as targeting moiety. From an immune camel library, five VHH clones were selected as a set of oligoclonal anti-HER2 VHHs that exhibited diverse binding abilities and joined them to CD28-CD3ζ and CD28-OX40-CD3ζ signaling endodomains. Jurkat T cells expression of VHH-CARs and cell functions were evaluated. RESULTS: The oligoclonal engineered T cells showed higher proliferation, cytokine secretion and cytotoxicity than each individual VHH-CAR-engineered Jurkat T cells. CONCLUSIONS: The combination of superior targeting ability of oligoclonal VHHs with the third generation CAR can substantially improve the function of engineered T cells. GENERAL SIGNIFICANCE: Antigen-specific directed oligoclonal T cells are alternatively promising, but safer systems, to combat tumor cells.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Neoplasias/imunologia , Receptor ErbB-2/imunologia , Receptores de Antígenos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Domínio Único/imunologia , Linfócitos T/imunologia , Apoptose , Western Blotting , Proliferação de Células , Citometria de Fluxo , Humanos , Células Jurkat , Neoplasias/metabolismo , Neoplasias/terapia , Engenharia de Proteínas , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Antígenos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Linfócitos T/metabolismo , Células Tumorais Cultivadas
14.
Cancer Lett ; 334(2): 237-44, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22902507

RESUMO

Despite the preclinical success of adoptive therapy with T cells bearing chimeric nanoconstructed antigen receptors (CARs), certain limitations of this therapeutic approach such as the immunogenicity of the antigen binding domain, the emergence of tumor cell escape variants and the blocking capacity of soluble antigen still remain. Here, we address these issues using a novel CAR binding moiety based on the oligoclonal camelid single domain antibodies. A unique set of 13 single domain antibodies were selected from an immunized camel phage library based on their target specificity and binding affinity. A combination of these single domain antibodies was used to generate four tumor associated glycoprotein (TAG-72)-specific CARs harboring an identical antigen binding site, but with different signaling and spacer domains. Although all four CARs were functionally active against the TAG-72 expressing tumor cells, the combination of CD3ζ, OX40, CD28 as well as the CH3-CH2-hinge-hinge domains most efficiently triggered T cell activation. Importantly, CAR mediated functions were not blocked by the soluble TAG-72 antigen at a supraphysiological concentration. Our approach may have the potential to reverse multiple tumor immune evasion mechanisms, avoid CAR immunogenicity, and overcome problems in cancer gene therapy with engineered nanoconstructs.


Assuntos
Antígenos de Neoplasias/imunologia , Engenharia Genética/métodos , Glicoproteínas/imunologia , Imunoterapia Adotiva/métodos , Receptores de Antígenos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Domínio Único/imunologia , Linfócitos T/imunologia , Animais , Especificidade de Anticorpos , Antígenos de Neoplasias/genética , Camelídeos Americanos , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/terapia , Neoplasias do Colo/imunologia , Neoplasias do Colo/terapia , Glicoproteínas/genética , Células HT29 , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Leucemia de Células T/imunologia , Leucemia de Células T/terapia , Ativação Linfocitária , Biblioteca de Peptídeos , Receptores de Antígenos/genética , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais , Anticorpos de Domínio Único/genética , Linfócitos T/fisiologia , Transfecção
15.
Exp Cell Res ; 318(10): 1112-24, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22440788

RESUMO

Modern anti-HER2 antibody therapy tends to exploit a panel of different antibodies against different epitopes on the antigen. For this aim, nanobodies are very striking targeting agents and can be easily produced against any cell-specific membrane antigen. The oligoclonal nanobodies can be used to block more than one functional epitope on a target antigen and inhibit the generation of escape variants associated with cancer therapy. In this study, 12 nanobody clones selected from an immune camel library were examined for their ability to differ between tumor markers. These oligoclonal nanobodies targeted breast cancer cells better than each individual nanobody. In epitope mapping, several nanobodies overlapped in the epitope recognized by trastuzumab and some of the non-overlapping nanobodies could affect the binding of trastuzumab to HER2. This study demonstrates that the oligoclonal nanobodies are potential therapeutic tools that can be used instead of, or in combination with trastuzumab to assess tumor viability during treatment.


Assuntos
Epitopos/imunologia , Fragmentos de Imunoglobulinas/biossíntese , Cadeias Pesadas de Imunoglobulinas/biossíntese , Receptor ErbB-2/imunologia , Animais , Anticorpos Monoclonais Humanizados/química , Afinidade de Anticorpos , Especificidade de Anticorpos , Antineoplásicos/química , Ligação Competitiva , Camelus , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Citometria de Fluxo , Humanos , Fragmentos de Imunoglobulinas/química , Fragmentos de Imunoglobulinas/isolamento & purificação , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/isolamento & purificação , Camundongos , Biblioteca de Peptídeos , Ligação Proteica , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Trastuzumab
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