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1.
Chinese Journal of Biotechnology ; (12): 290-300, 2021.
Article in Chinese | WPRIM | ID: wpr-878562

ABSTRACT

For improving epitope immunogenicity and achieving the co-immunization, late protein 1 (L1) of HPV type 16 (HPV16L1) was selected as the vector to carry the dominant epitope of Toxoplasma gondii because of the shared common population between Toxoplasma gondii and human papillomavirus (HPV). RSepitope-HPV16L1 (RSepitope fused at the "N-terminus" of HPV16L1) and HPV16L1-RSepitope (RSepitope fused at the "C-terminus" of HPV16L1) chimeras were constructed. After transfection of COS-7 cells with the recombinants, Western blot, RT-PCR, and immunofluorescence experiments confirmed that RSepitope-HPV16L1 could successfully express the corresponding mRNA and protein of RSepitope and HPV16L1, but the HPV16L1-RSepitope construct could not. A "prime-boost" immunization program was applied in mice to further evaluate the immune response elicited by the constructs, and the RSepitope-HPV16L1 immunization group produced the most significantly increased humoral and cellular immune responses (the highest RSepitope-specific IgG antibody level and the highest IFN-γ production, respectively), in which both elevated Th1 and Th2 immune responses were obtained. Moreover, the advantage of HPV16L1 as an epitope carrier was remarkable for RSepitope-HPV16L1, which induced a more prominent immunological response than RSepitope alone (without fusion with HPV16L1). Our research indicated that the N-terminus of HPV16L1 could be a better insertion site for enhancing target epitope immunogenicity, and our study offers a design for epitope vaccine of reasonable combination.


Subject(s)
Animals , Antibody Formation , Epitopes , Immunization , Mice , Mice, Inbred BALB C , Toxoplasma , Vaccination , Vaccines, DNA
2.
Rev. chil. nutr ; 47(3): 463-469, jun. 2020. tab
Article in English | LILACS | ID: biblio-1126145

ABSTRACT

The addition of soy proteins, currently classified as a food allergen, into meat products is a commonly used practice due to its functional properties and low cost. Its addition to meat products can cause health problems for individuals allergic to these proteins. Allergic individuals can be affected by the ingestion of low amounts of the allergen. In Brazil, limits are set for the addition of soy proteins in meat products in order to avoide fraud. Starting in 2015 reporting the name of the added component became mandatory for all food labelling. Some studies have reported that food processing can reduce the allergenicity, either by irreversible removal of allergens or by modifying the allergen structure. However, the technological approach to decrease allergenicity has largely been empirical. This review describes the use of soy protein in meat products and the health risk for allergic individuals and consumers of these products. Finally, appropriate methodologies for the detection and quantification of these proteins must be further explored and established to avoid fraud and to preserve consumer health.


La adición de proteínas de soya, actualmente clasificadas como alergeno alimentario, en los productos cárnicos es una práctica comúnmente utilizada debido a sus propiedades funcionales y bajo costo. Su adición en productos cárnicos puede causar problemas de salud en personas alérgicas a estas proteínas. Las personas alérgicas pueden verse afectadas por la ingestión de cantidades diminutas de alérgeno. En Brasil, se establecen límites para la adición de proteínas de soya en los productos cárnicos con el objetivo de evitar el fraude. Solo en 2015 se hizo obligatoria la declaración en la etiqueta de todos los alimentos que indicaban la presencia de sustancias alérgicas, así como el nombre del componente. Algunos estudios se refieren al procesamiento de alimentos para reducir la alergenicidad, ya sea mediante la eliminación irreversible de alergenos o modificando la estructura del alergeno; sin embargo, el enfoque tecnológico hasta ahora para disminuir la alergenicidad ha sido en gran medida empírico. Esta revisión describe el uso de proteína de soya en los productos cárnicos y el riesgo que puede causar para la salud de las personas alérgicas y a los consumidores de estos productos. Finalmente, las metodologías apropiadas para la detección y cuantificación de estas proteínas deben explorarse en profundidad y establecerse para evitar el fraude y preservar la salud de los consumidores.


Subject(s)
Humans , Plant Proteins, Dietary/adverse effects , Soybean Proteins/adverse effects , Food Hypersensitivity/etiology , Meat Products , Allergens , Health Risk , Food Hypersensitivity/prevention & control , Epitopes
3.
Braz. j. infect. dis ; 24(1): 85-88, Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1089325

ABSTRACT

ABSTRACT The antigenic potential of seven immunogenic peptides of the dengue virus was evaluated in the sera of patients with dengue confirmed by IgM/IgG serology. Antibodies IgM and IgG against dengue virus peptides were analyzed by ELISA in 31 dengue sero-positive and 20 sero-negative patients. The P5 peptide showed significant IgG immunoreactivity mostly in the sera of patients with dengue without warning signs in comparison with patients with dengue with warning signs, correlating with mild disease. This finding suggests that the low antibody response against P5 epitope could be a risk factor for higher susceptibility to dengue virus infection with warning signs, and that P5 could be a potential antigen for vaccine development.


Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Aged , Young Adult , Peptides/immunology , Viral Envelope Proteins/immunology , Dengue Virus/immunology , Dengue Vaccines , Antibodies, Viral/immunology , Epitopes/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Enzyme-Linked Immunosorbent Assay , Statistics, Nonparametric , Dengue/immunology , Dengue/prevention & control , Antibody Formation , Antigens, Viral/immunology
6.
Chinese Journal of Biotechnology ; (12): 2443-2450, 2020.
Article in Chinese | WPRIM | ID: wpr-878500

ABSTRACT

To establish a method for identifying protein epitopes recognized by therapeutic monoclonal antibodies, the programmed death receptor-1 (PD-1) was selected as the target protein. Based on the alanine scanning strategy, a rapid expression method of antigen mutants combining site-directed mutagenesis with mammalian cell expression system was established, the conditions for eukaryotic expression element amplification and cell transfection expression were established. 150 PD-1 protein mutants were co-expressed, and the binding ability of these mutants to anti-PD-1 antibody Pembrolizumab was identified. The epitopes of Pembrolizumab were determined based on the binding ability of protein mutants to antibodies and combined with protein structure analysis, which was highly consistent with the reported crystal structure-based epitopes, indicating that this method is simple and accurate and can be used for epitope mapping of therapeutic monoclonal antibodies.


Subject(s)
Animals , Antibodies, Monoclonal , Antigens , Epitope Mapping , Epitopes/genetics
7.
Chinese Journal of Biotechnology ; (12): 1069-1082, 2020.
Article in Chinese | WPRIM | ID: wpr-826869

ABSTRACT

Monoclonal antibody (mAb) is an important biological macromolecule and widely used in immune detection, in vitro diagnostics, and drug discovery. However, the inherent properties of mAb restrict its further development, such as high molecular weight and complex structure. Therefore, there is an urgent need to develop alternatives for mAb. Various types of miniaturized antibodies have been developed, among which the variable domain of immunoglobulin new antigen receptor (VNAR) is very attractive. The shark single-domain antibody, also known as shark VNAR, is an antigen-binding domain obtained by genetic engineering technology based on the immunoglobulin new antigen receptor (IgNAR) that naturally exists in selachimorpha. It has a molecular weight of 12 kDa, which is the smallest antigen-binding domain found in the known vertebrates at present. Compared with mAb, the shark VNAR exhibits various superiorities, such as low molecular weight, high affinity, tolerance to the harsh environment, good water solubility, strong tissue penetration, and recognition of the hidden epitopes. It has attracted wide attention in the fields of immunochemical reagents and drug discovery. In this review, various aspects of shark VNAR are elaborated, including the structural and functional characteristics, generating and humanization techniques, affinity maturation strategies, application fields, advantages and disadvantages, and prospects.


Subject(s)
Animals , Antibodies, Monoclonal , Allergy and Immunology , Antibodies, Monoclonal, Humanized , Allergy and Immunology , Antigens , Epitopes , Metabolism , Protein Domains , Allergy and Immunology , Receptors, Antigen , Chemistry , Allergy and Immunology , Sharks
8.
Article in Chinese | WPRIM | ID: wpr-828487

ABSTRACT

OBJECTIVE@#To provide data support for the study of pathogenic mechanism of SARS-CoV-2 at the molecular level, and provide suitable candidate targets for vaccine, antibody and drug research and development through comparative analysis for structural characteristics and epitopes of S protein of SARS-CoV-2 and SARS-CoV.@*METHODS@#Based on the reference sequences of S protein, physical and chemical properties, hydrophobicity, signal peptide, transmembrane region, domain, secondary structure, tertiary structure analysis and antigenic epitopes prediction were carried out. Meanwhile, the tissue expression, related pathways and reactome pathways of angiotensis Ⅰ converting enzyme 2 (ACE2) and C-type lectin domain family 4 member M (CLEC4M) receptors were analyzed.@*RESULTS@#The amino acid sequence of S protein of SARS-CoV-2 and SARS-CoV has a 75.80% consistency. The structural characteristics of the two coronaviruses are highly consistent, but the secondary structure and tertiary structure of SARS-CoV-2 is not as obvious as SARS-CoV. ACE2 and CLEC4M are expressed in alimentary system, heart, kidney, lung and placenta. The main related the pathways of renin-angiotensin system, protein digestion and absorption pathway, and the reactome pathways of metabolism of angiotensinogen to angiotensins, GPCR ligand binding, are related to typical symptoms of coronavirus disease 2019 induced by SARS-CoV-2. Three pairs of highly or completely homologous epitopes of S protein were obtained. The 600-605, 695-703 and 888-896 amino acid residues in SARS-CoV-2 were highly homologous with 586-591, 677-685 and 870-878 amino acid residues in SARS-CoV, respectively.@*CONCLUSIONS@#The similarity of S protein of SARS-CoV-2 and SARS-CoV determines that they have similar infection patterns and clinical manifestations. The candidate epitopes with high reliability can provide reference for virus diagnosis and vaccine development.


Subject(s)
Betacoronavirus , Cell Adhesion Molecules , Coronavirus Infections , Epitopes , Humans , Lectins, C-Type , Ligands , Pandemics , Peptidyl-Dipeptidase A , Pneumonia, Viral , Receptors, Cell Surface , Receptors, Virus , Reproducibility of Results , Spike Glycoprotein, Coronavirus
9.
Electron. j. biotechnol ; 40: 65-70, July. 2019. ilus
Article in English | LILACS | ID: biblio-1053486

ABSTRACT

Background: In Saccharomyces cerevisiae, Msn2, which acts as a key transcription factor downstream the MAPKHOG cascade pathway, also regulates the expression of genes related to stress responses. However, little is known about the regulation mechanisms of the transcription factor in Setosphaeria turcica. Results: In this study, a zinc finger DNA-binding protein, designated as StMSN2, was cloned from S. turcica. Sequencing results showed that StMSN2 had a 1752 bp open reading frame (ORF), which was interrupted by an intron (135 bp) and encoded a putative 538-amino acid protein. Phylogenetic analysis further revealed that StMsn2 was more closely related to Msn2 of Aspergillus parasiticus. StMSN2 was cloned into the pET-28a vector with His (Histidine) tags and induced with 1 mM IPTG (isopropyl-ß-D-thiogalactoside) at 37°C. The recombinant His-tagged StMsn2 was purified, and a band of size approximately 58.8 kDa was obtained. The high specificity of the polyclonal antibody Msn2-2 was detected with the StMsn2 protein from S. turcica and prokaryotic expression system, respectively. Conclusions: A new gene, named StMSN2, with 1617 bp ORF was cloned from S. turcica and characterized using bioinformatics methods. StMsn2 was expressed and purified in a prokaryotic system. A polyclonal antibody, named Msn2-2, against StMsn2 with high specificity was identified.


Subject(s)
Plant Diseases , Ascomycota/genetics , Ascomycota/pathogenicity , Transcription Factors/isolation & purification , Ascomycota/metabolism , Stress, Physiological , Transcription Factors/genetics , Transcription Factors/metabolism , Carrier Proteins , Gene Expression , Blotting, Western , Open Reading Frames , Zinc Fingers , Cloning, Molecular , Zea mays , Escherichia coli , Helminthosporium , Epitopes
10.
Rev. Soc. Bras. Med. Trop ; 52: e20180139, 2019. graf
Article in English | LILACS | ID: biblio-1041506

ABSTRACT

Abstract INTRODUCTION: High percentages of structural identity and cross-immunoreactivity have been reported between potato apyrase and Schistosoma mansoni ATP diphosphohydrolase (SmATPDases) isoforms, showing the existence of particular epitopes shared between these proteins. METHODS: Potato apyrase was employed using ELISA, western blot, and mouse immunization methods to verify IgE reactivity. RESULTS: Most of the schistosomiasis patient's (75%) serum was seropositive for potato apyrase and this protein was recognized using western blotting, suggesting that parasite and plant proteins share IgE-binding epitopes. C57BL/6 mice immunized with potato apyrase showed increased IgE antibody production. CONCLUSIONS: Potato apyrase and SmATPDases have IgE-binding epitopes.


Subject(s)
Animals , Female , Apyrase/immunology , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Solanum tuberosum/enzymology , Immunoglobulin E/immunology , Antibodies, Helminth/immunology , Epitopes/immunology , Enzyme-Linked Immunosorbent Assay , Blotting, Western , Cross Reactions , Mice, Inbred C57BL
11.
Article in English | WPRIM | ID: wpr-758884

ABSTRACT

Monoclonal antibodies (MAbs) are widely applied in disease diagnoses. Herein, we report a MAb, WF-4, against Influenza A virus nucleoprotein (NP), its broad response with Influenza A virus, and its application in an immunohistochemistry (IHC) assay. WF-4 was screened by immunofluorescence assay (IFA). The results showed that its reactivity with baculovirus-expressed full-length recombinant NP (rNP) in Western blot (WB), indicating its IHC applicability. Fifteen Influenza A virus (reference subtypes H1 to H15) infected chicken embryonated chorioallantoic membranes (CAM), fixed by formalin, were all detectable in the WF-4-based IHC assay. Also, the reactivity of the IHC test with NP from experimentally inoculated H6N1 and from all recent outbreaks of H5 subtype avian Influenza A virus (AIV) field cases in Taiwan showed positive results. Our data indicate that CAM, a by-product of Influenza A virus preparation, is helpful for Influenza A virus-specific MAb characterization, and that the WF-4 MAb recognizes conserved and linear epitopes of Influenza A virus NP. Therefore, WF-4 is capable of detecting NP antigens via IHC and may be suitable for developing various tests for diagnosis of Influenza A virus and, especially, AIV infection.


Subject(s)
Animals , Antibodies, Monoclonal , Blotting, Western , Chickens , Chorioallantoic Membrane , Diagnosis , Disease Outbreaks , Epitopes , Fluorescent Antibody Technique , Formaldehyde , Immunohistochemistry , Influenza A virus , Influenza in Birds , Influenza, Human , Nucleoproteins , Taiwan
12.
Chinese Journal of Biotechnology ; (12): 1174-1183, 2019.
Article in Chinese | WPRIM | ID: wpr-771811

ABSTRACT

With the rapid development of antibody genetic engineering, bispecific antibody technology has been advanced. They are capable of binding two or more different epitopes simultaneously, thus offering specific advantages over natural monoclonal antibodies in immunotherapy. Bispecific antibodies have been successfully used in cancer therapy (e.g. melanoma, Hodgkin's lymphoma, liver cancer, and stomach cancer) and inflammation therapy (e.g. rheumatoid arthritis, psoriasis and Crohn's disease), but are still in their early stage for viral immunotherapy. In this study, we reviewed the research progress of bispecific antibodies for immunotherapy of virus infections, especially those with good effects in vivo and in vitro, to provide references for the research and development of bispecific antibodies for antivirus treatment.


Subject(s)
Antibodies, Bispecific , Therapeutic Uses , Antibodies, Monoclonal , Epitopes , Humans , Immunotherapy , Virus Diseases
13.
Chinese Journal of Biotechnology ; (12): 718-725, 2019.
Article in Chinese | WPRIM | ID: wpr-771338

ABSTRACT

Multi-epitope recombinant diagnostic antigen (designated 'B102') of Mycobacterium tuberculosis (Mtb) was prepared and evaluated as a serological diagnostic antigen. With TRX at the N-terminal and His tag at the C-terminal, the multi-epitope Mtb recombinant diagnostic antigen including 11 predicted B-cell epitopes from 6 Mtb antigens (PstS1, ESAT6, CFP10, Ag85B, Ag85A and PPE54) was expressed in Escherichia coli BL21 (DE3) and purified by Ni²⁺-Chelating affinity and DEAE anion exchange chromatography. Based on the antigenicity of B102 confirmed in Western blotting analysis, we constructed and evaluated a double-antigen sandwich ELISA for diagnosis of Mtb infection. The protein B102 exists in the form of inclusion bodies, accounting for 31.25% of the total proteins of the bacteria. After purification and renaturation, protein B102 exists in soluble form with the concentration 3.124 mg/mL and the homogeneity 96.71%. WB analysis demonstrated that protein B102 could react with antibodies in Mtb positive serum. Using the novel antigen in ELISA, we tested 60 Mtb-related positive and negative serum; The results showed the sensitivity, specificity, positive and negative predictive values and coincidence rate of the detection method is 90.00%, 93.33%, 93.10%, 90.32% and 91.67%, respectively. The McNemer analysis suggested there was no statistical difference between the 'Gold standard' and the novel ELISA with kappa 0.833, which suggested the excellent consistency. By prokaryotic expression and chromatography purification, the multi-epitope recombinant antigen B102 was obtained with excellent antigenicity, which could be applied for Mtb-related serological detection.


Subject(s)
Antigens, Bacterial , Bacterial Proteins , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Epitopes , Escherichia coli , Mycobacterium tuberculosis
14.
Article in English | WPRIM | ID: wpr-719491

ABSTRACT

Toxoplasmosis is a cosmopolitan zoonotic infection, caused by a unicellular protozoan parasite known as Toxoplasma gondii that belongs to the phylum Apicomplexa. It is estimated that over one-third of the world's population has been exposed and are latently infected with the parasite. In humans, toxoplasmosis is predominantly asymptomatic in immunocompetent persons, while among immunocompromised individuals may be cause severe and progressive complications with poor prognosis. Moreover, seronegative pregnant mothers are other risk groups for acquiring the infection. The life cycle of T. gondii is very complex, indicating the presence of a plurality of antigenic epitopes. Despite of great advances, recognize and construct novel vaccines for prevent and control of toxoplasmosis in both humans and animals is still remains a great challenge for researchers to select potential protein sequences as the ideal antigens. Notably, in several past years, constant efforts of researchers have made considerable advances to elucidate the different aspects of the cell and molecular biology of T. gondii mainly on microneme antigens, dense granule antigens, surface antigens, and rhoptry proteins (ROP). These attempts thereby provided great impetus to the present focus on vaccine development, according to the defined subcellular components of the parasite. Although, currently there is no commercial vaccine for use in humans. Among the main identified T. gondii antigens, ROPs appear as a putative vaccine candidate that are vital for invasion procedure as well as survival within host cells. Overall, it is estimated that they occupy about 1%–30% of the total parasite cell volume. In this review, we have summarized the recent progress of ROP-based vaccine development through various strategies from DNA vaccines, epitope or multi epitope-based vaccines, recombinant protein vaccines to vaccines based on live-attenuated vectors and prime-boost strategies in different mouse models.


Subject(s)
Animals , Antigens, Surface , Apicomplexa , Cell Size , Epitopes , Humans , Immunization , Life Cycle Stages , Mice , Molecular Biology , Mothers , Parasites , Prognosis , Toxoplasma , Toxoplasmosis , Vaccines , Vaccines, DNA , Vaccines, Synthetic , Zoonoses
15.
Article in English | WPRIM | ID: wpr-719487

ABSTRACT

PURPOSE: The influenza B virus diverges into two antigenically distinct lineages: B/Yamagata and B/Victoria. Influenza B is the dominant circulating virus during some influenza seasons, and recent data demonstrated that influenza A and B infection similarly cause severe clinical symptoms in hospitalized patients. Nucleoprotein (NP) is a good target for a universal influenza vaccine. This study investigated whether NP epitope variation within two lineages affects the dominant cytotoxic T lymphocyte (CTL) responses induced by vaccination and the resultant protective immunity. MATERIALS AND METHODS: The NP of B/Yamagata/16/1988, the representative strain of the Yamagata lineage, includes a dominant CTL epitope, FSPIRITFL, while B/Shangdong/7/1997 from the Victoria lineage has one amino acid difference in this sequence, FSPIRVTFL. Two recombinant replication-deficient adenovirus (rAd)-vectored vaccines expressing either NP were prepared (rAd/B-NP(I) and rAd/B-NP(V), respectively) and administered to BALB/c mice intranasally. To examine the efficacy of vaccination, antibody responses, CTL responses, and morbidity/mortality after challenge were measured. RESULTS: Both vaccines induce similar antibody and CD8 T-cell responses cross-reacting to both epitopes, and also confer cross-protection against both lineages regardless of amino acid difference. CONCLUSION: The rAd-vectored vaccine expressing the NP could be developed as universal influenza B vaccine which provides broader protection.


Subject(s)
Adenoviridae , Animals , Antibody Formation , Epitopes , Humans , Influenza B virus , Influenza Vaccines , Influenza, Human , Lymphocytes , Mice , Nucleoproteins , Seasons , T-Lymphocytes , T-Lymphocytes, Cytotoxic , Vaccination , Vaccines , Victoria
16.
Rev. patol. trop ; 47(4): 217-224, dez. 2018. tab, ilus
Article in English | LILACS | ID: biblio-996634

ABSTRACT

Cases of Lymphatic Filariasis (LF) have been notified since 1959 in the municipality of Paulista, yet it is still considered an LF-free area. The purpose of this study was to describe the situation of Paulista Health Department. The data were gathered via antigenic surveys carried out in the town, using POC-ICT-AD12 tests. A total of 1,000 individuals, aged 10 and over, were examined in the neighborhoods of Mirueira, Engenho Maranguape, Janga and Maranguape II (250 individuals in each district). Among the individuals evaluated, seven (0,7%) tested positive for antigens using CFA POC-ICT-AD12, 5 out of 250 (2.0%) in the Engenho Maranguape neighborhood and 2 out of 250 (0.8%) in Janga. In this group, one particular individual presented microfilaremia, quantified at 5 Mf/mL. These results suggest that the municipality of Paulista might be a "silent" source of LF continuous transmission, fact that could impact negatively on the goals of the GPELF program meant to provide certification of parasitic disease control and elimination by the year 2022


Subject(s)
Humans , Parasitic Diseases , Elephantiasis, Filarial , Microfilariae , Epitopes
17.
Rev. bras. parasitol. vet ; 27(3): 267-279, July-Sept. 2018. graf
Article in English | LILACS | ID: biblio-959193

ABSTRACT

Abstract The cattle tick Rhipicephalus microplus causes significant economic losses in agribusiness. Control of this tick is achieved mainly through the application of chemical acaricides, often resulting in contamination of animal food products and of the environment. Another major concern associated with acaricide use is the increasing reports of resistance of this tick vector against the active ingredients of many commercial products. An alternative control method is vaccination. However, the commercially available vaccine based on a protein homologous to Bm86 exhibits variations in efficacy relative to the different geographical locations. This study aimed to identify antigenic determinants of the sequences of proteins homologous to Bm86. Phylogenetic analyses were performed to determine the extent of divergence between different populations of R. microplus to identify the sequence that could be used as a universal vaccine against the multiple geographically distinct populations of R. microplus and related tick species. Considering the extensive sequence and functional polymorphism observed among strains of R. microplus from different geographical regions, we can conclude that it may be possible to achieve effective vaccination against these cattle ticks using a single universal Bm86-based antigen.


Resumo O carrapato Rhipicephalus microplus é responsável por perdas significativas no agronegócio. O controle deste carrapato é feito principalmente por meio da aplicação de acaricidas químicos, geralmente resultando na contaminação de produtos de origem animal e do meio ambiente. Outra preocupação importante associada ao uso de acaricidas é o crescente aumento de relatos sobre a resistência deste carrapato a princípios ativos de vários produtos comerciais. Uma alternativa de controle é por meio de vacinação. Porém, a vacina comercializada contendo proteína homóloga à Bm86, apresenta variações de eficácia em relação às diferentes localizações geográficas. Este estudo buscou identificar determinantes antigênicos das sequencias de proteínas homólogas a Bm86. As análises filogenéticas foram feitas para determinar a extensão da divergência entre diferentes populações de R. microplus com o objetivo de identificar a sequência que poderia ser usada como vacina universal contra as múltiplas populações geograficamente distintas de R. microplus e espécies de carrapatos relacionados. Considerando-se a extensa sequência e o polimorfismo observados entre linhagens de R. microplus de diferentes regiões geográficas, podemos concluir que pode ser possível obter uma vacinação efetiva contra esses carrapatos bovinos utilizando um único antígeno universal baseado em Bm86.


Subject(s)
Animals , Cattle , Tick Infestations/prevention & control , Vaccines/chemistry , Proteins/immunology , Cattle Diseases/prevention & control , Rhipicephalus/immunology , Epitopes/immunology , Vaccines/administration & dosage
18.
Article in English | WPRIM | ID: wpr-758781

ABSTRACT

Rotavirus (RV)-infected piglets are presumed to be latent sources of heterologous RV infection in humans and other animals. In RVs, non-structural protein 4 (NSP4) is the major virulence factor with pleiotropic properties. In this study, we analyzed the nsp4 gene from porcine RVs isolated from diarrheic and non-diarrheic cases at different levels of protein folding to explore correlations to diarrhea-inducing capabilities and evolution of nsp4 in the porcine population. Full-length nsp4 genes were amplified, cloned, sequenced, and then analyzed for antigenic epitopes, RotaC classification, homology, genetic relationship, modeling of NSP4 protein, and prediction of post-translational modification. RV presence was observed in both diarrheic and non-diarrheic piglets. All nsp4 genes possessed the E1 genotype. Comparison of primary, secondary, and tertiary structure and the prediction of post-translational modifications of NSP4 from diarrheic and non-diarrheic piglets revealed no apparent differences. Sequence analysis indicated that nsp4 genes have a multi-phyletic evolutionary origin and exhibit species independent genetic diversity. The results emphasize the evolution of the E9 nsp4 genotype from the E1 genotype and suggest that the diarrhea-inducing capability of porcine RVs may not be exclusively linked to its enterotoxin gene.


Subject(s)
Animals , Classification , Clone Cells , Enterotoxins , Epitopes , Genetic Variation , Genotype , Humans , Protein Folding , Protein Processing, Post-Translational , Rotavirus , Sequence Analysis , Viral Nonstructural Proteins , Virulence
19.
Article in English | WPRIM | ID: wpr-739640

ABSTRACT

Toxoplasma gondii belongs to the Apicomplexa phylum that caused a widespread zoonotic infection in wide range of intermediate hosts. Over one-third of the world's population are latently infected with T. gondii and carry it. The complex life cycle of T. gondii indicates the presence of a plurality of antigenic epitopes. During the recent years, continuous efforts of scientists have made precious advances to elucidate the different aspects of the cell and molecular biology of T. gondii. Despite of great progresses, the development of vaccine candidates for preventing of T. gondii infection in men and animals is still remains a challenge. The calcium-dependent protein kinases (CDPKs) belongs to the superfamily of kinases, which restricted to the apicomplexans, ciliates, and plants. It has been documented that they contribute several functions in the life cycle of T. gondii such as gliding motility, cell invasion, and egress as well as some other critical developmental processes. In current paper, we reviewed the recent progress concerning the development of CDPK-based vaccines against acute and chronic T. gondii.


Subject(s)
Animals , Apicomplexa , Cell Movement , Epitopes , Humans , Immunization , Life Cycle Stages , Male , Molecular Biology , Phosphotransferases , Protein Kinases , Toxoplasma , Vaccines , Zoonoses
20.
Article in English | WPRIM | ID: wpr-690650

ABSTRACT

<p><b>OBJECTIVE</b>To eliminate the side effects of aluminum adjuvant and His-tag, we constructed chimeric VLPs displaying the epitope of EV71 (SP70) without His-tagged. Then evaluating whether the VLPs could efficiently evoke not only humoral but also cellular immune responses against EV71 without adjuvant.</p><p><b>METHODS</b>The fusion protein was constructed by inserting SP70 into the MIR of truncated HBcAg sequence, expressed in E. Coli, and purified through ion exchange chromatography and density gradient centrifugation. Mice were immunized with the VLPs and sera were collected afterwards. The specific antibody titers, IgG subtypes and neutralizing efficacy were detected by ELISA, neutralization assay, and EV71 lethal challenge. IFN-γ and IL-4 secreted by splenocytes were tested by ELISPOT assay.</p><p><b>RESULTS</b>HBc-SP70 proteins can self-assemble into empty VLPs. After immunization with HBc-SP70 VLPs, the detectable anti-EV71 antibodies were effective in neutralizing EV71 and protected newborn mice from EV71 lethal challenge. There was no significant difference for the immune efficacy whether the aluminum adjuvant was added or not. The specific IgG subtypes were mainly IgG1 and IgG2b and splenocytes from the mice immunized produced high levels of IFN-γ and IL-4.</p><p><b>CONCLUSION</b>The fusion proteins without His-tagged was expressed and purified as soluble chimeric HBc-SP70 VLPs without renaturation. In the absence of adjuvant, they were efficient to elicit high levels of Th1/Th2 mixed immune response as well as assisted by aluminum adjuvant. Furthermore, the chimeric VLPs have potential to prevent HBV and EV71 infection simultaneously.</p>


Subject(s)
Adjuvants, Immunologic , Animals , Antibodies, Neutralizing , Antibodies, Viral , Blood , Enterovirus A, Human , Genetics , Enterovirus Infections , Allergy and Immunology , Virology , Epitopes , Allergy and Immunology , Metabolism , Escherichia coli , Metabolism , Female , Immunity, Cellular , Immunity, Humoral , Mice , Recombinant Fusion Proteins , Allergy and Immunology
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