Computer-Aided vaccine design for selected positive-sense single stranded RNA viruses

Spontaneous mutations and lack of replication fidelity in positive-sense single stranded RNA viruses (+ssRNA virus) result in emergence of genetic variants with diverse viral morphogenesis and surface proteins that affect its antigenicity. This high mutability in +ssRNA viruses has induced antiviral drug resistance and ability to overcome vaccines that subsequently resulted in rapid viral evolution and high mortality rate in human and livestock. Computer aided vaccine design and immunoinformatics play a crucial role in expediting the vaccine production protocols, antibody production and identifying suitable immunogenic regions or epitopes from the genome sequences of the pathogens. T cell and B cell epitopes can be identified in pathogens by immunoinformatics algorithms and methods that enhance the analysis of protective immunity, vaccine safety, immunity modelling and vaccine efficacy. This rapid and cost-effective computational vaccine design promotes development of potential vaccine that could induce immune response in host against rapidly mutating pathogens like +ssRNA viruses. Epitope-based vaccine is a striking concept that has been widely employed in recent years to construct vaccines targeting rapidly mutating +ssRNA viruses. Therefore, the present review provides an overview about the current progress and methodology in computeraided vaccine design for the most notable +ssRNA viruses namely Hepatitis C virus, Dengue virus, Chikungunya virus and Coronaviruses. This review also highlights the applications of various immunoinformatics tools for vaccine design and for modelling immune response against +ssRNA viruses.

Shared epitope classification methods according to Gregersen and de Vries allow adequate characterization of patients with rheumatoid arthritis in a Colombian population

Introduction: The most important genetic association in rheumatoid arthritis (RA) is presented with some alleles from the HLA-DRB1 gene that encode the shared epitope (SE). Objectives: To apply the SE classification methods of Gregersen, de Vries, Raychaudhuri, Mattey, and Tezenas du Montcel in a group of Colombian patients with RA and determine the most common HLA-DRB1 alleles in the population. Methods: RA diagnosis, genetic study of the HLA-DRB1 region using Luminex technology in 50 RA and 50 healthy subjects. For the classification analysis, Fisher's exact test and chi-squared test were applied. Tables were created to count the RA-related alleles. We used odds ratio to determine the risk between the presence of the shared epitope (SE) and anti-cyclic citrullinated peptides (Anti-CCP). Results: Gregersen and de Vries methods were suitable for the characterization of RA in this population (p = .006). The most prevalent HLA-DRB1 alleles in the RA group were 14:02,04:04, 08:02,04:05, and 10:01. High frequencies of the 07:01, 03:01,13:02,01:02, and 12:01 HLA-DRB1 alleles were found in the healthy population. HLA-DRB1 alleles with similar distribution in both populations were 04:07, 15:01, 11:01, 16:02, and 01:01. A high frequency of SE + was observed in Anti-CCP + individuals (63.15%); however, this was not statistically significant [OR2.4 (.63-9.01); p = .19]. Conclusion: The SE classification methods of Gregersen and de Vries were adequate in characterizing RA in a Colombian population group. An equivalence of 100% was verified between the susceptibility alleles defined by de Vries and the alleles assigned as SE according to Gregersen.

Introducción: La asociación genética más importante en artritis reumatoide (AR) se presenta con algunos alelos del gen HLA DRB1 que codifican el epítope compartido (EC). Objetivos: Aplicar los métodos de clasificación de EC de Gregersen et al., de Vries et al., Raychaudhuri et al., Mattey et al., y Tezenas du Montcel et al., en un grupo de pacientes colombianos con AR, y determinar los alelos HLA DRB1 más frecuentes en esta población. Métodos: Diagnóstico para AR, estudio genético de la región HLA DRB1 por tecnología Luminex® de 50 sujetos AR y 50 sanos. Para análisis comparativos de clasificaciones EC, se aplicaron las pruebas test exacto de Fisher y Chi-cuadrado y se realizaron tablas de conteos para los alelos relacionados con AR. Se estimó la razón de odds para determinar el riesgo entre la presencia de EC y los anticuerpos antipéptidos cíclicos citrulinados (anti-PCC). Resultados: Los métodos de Gregersen et al. y de Vries et al. fueron adecuados para la caracterización de AR en esta población (p = 0,006). Los alelos HLA DRB1 más prevalentes en el grupo AR fueron 14:02, 04:04, 08:02, 04:05 y 10:01. Se encontraron altas frecuencias de los alelos HLA DRB1 07:01, 03:01,13:02, 01:02 y 12:01 en población sana. Alelos HLA DRB1 con distribución similar en ambas poblaciones fueron: 04:07, 15:01, 11:01, 16:02 y 01:01. Se observó alta frecuencia de individuos EC+ en el grupo AR anti-PCC+ (63,15%); no obstante, sin asociación estadística (OR: 2,4 [0,63-9,01]; p = 0,19). Conclusión: Los métodos de clasificación para EC de Gregersen et al. y de Vries et al. fueron adecuados caracterizando AR en un grupo de población colombiana. Se corroboró equivalencia del 100% entre los alelos de susceptibilidad definidos por de Vries y los alelos asignados como EC según Gregersen et al.

Sequence characteristics of Rhipicephalus microplus Enolase gene and prediction of structure and antigenic epitopes of its encoding protein / 中国血吸虫病防治杂志

Objective To analyze the sequence characteristics of Rhipicephalus microplus Enolase gene, and to predict the secondary and tertiary structure and antigenic epitopes of the Enolase protein. Methods Sixty-two engorged female R. microplus were sampled from a yellow cattle breeding farm in Zhijiang County, Huaihua City, Hunan Province in June 25, 2022. Genomic DNA was isolated from R. microplus, and the Enolase gene was amplified using PCR assay, followed by cloning, sequencing and expression of the amplification product. The sequence characteristics of the Enolase gene were analyzed using the software Clustal X, and the gene sequence was translated into amino acid sequences. The secondary and tertiary structures of the Enolase protein were deduced using the software PRABI, and the physicochemical properties of the Enolase protein were analyzed using the software PRABI. In addition, the B- and T-cell epitopes of the Enolase protein were predicted using the software ABCpred Prediction, Scratch, IEDB and NetCTL. Results The R. microplus Enolase gene sequence was 1 323 bp in size, and the contents of A, T, G and C bases were 24.5%, 22.5%, 27.0% and 26.0%,with 47.0% of A + T content and 53.0% of G + C content. The R. microplus Enolase gene encoded 434 amino acids, and the Enolase protein had a molecular weight of 47.12 kDa. The secondary structure of the Enolase protein contained 186 α-helixes (42.86%), 32 β-turns (7.37%), 144 random coils (33.18%) and 72 extended strands (16.59%). The Enolase protein was most probably present in cytoplasm (76.7%), followed by in mitochondrion (39.1%) and nucleus (21.7%), and the Enolase protein had no signal peptide or transmembrane domain. In addition, the Enolase protein had 14 B-cell dominant epitopes and 8 T-cell dominant epitopes. Conclusions The R. microplus Enolase gene sequence exhibits a GC preference, and its encoding Enolase protein is an acidic and hydrophilic protein, with α-helixes and random coils as its primary structure, and presenting B- and T-cell dominant epitopes, which is a potential target for development of vaccines against R. microplus.

Design and antitumor activity of programmed cell death ligand 1 epitope peptide vaccine / 中国药科大学学报

@#Several programmed cell death protein 1 (PD-1) or its ligand (PD-L1) immune checkpoint blocking antibodies are available for clinical treatment, but only some patients show clinical response, so an alternative strategy for tumor immunotherapy is needed.A therapeutic tumor vaccine targeting PD-L1 is a meaningful attempt.In this study, we designed an epitope peptide vaccine targeting PD-L1, and then screened the immunogenic PD-L1 epitope peptide based on the humanized immune system (HIS) mouse model and further investigated its anti-tumor activity.The results show that the designed and screened PD-L1-B1 epitope peptide vaccine not only successfully induced PD-L1-specific humoral and cellular immunity, but also exhibit anti-tumor activity.In addition, immunotherapy increased T-lymphocyte infiltration of tumors and reshaped the tumor immunosuppressive microenvironment.In conclusion, PD-L1-B1 epitope peptide vaccine exhibits potent anti-tumor activity and may be an effective alternative immunotherapeutic strategy for patients insensitive to PD-1/PD-L1 blockade.

Epitope identification of calcitonin gene-related peptide antibodies based on ELISA and NMR methods / 中国生物制品学杂志

@#Objective To develop an indirect ELISA-based peptide scanning method combined with nuclear magnetic resonance(NMR)technique for the epitope identification of calcitonin gene-related peptide(CGRP)antibodies.Methods The antigen binding activities of two antibodies(new CGRP antibody and control antibody)were determined by indirect ELISA using each truncated CGRP fragment as coating antigen,and the linear epitope was analyzed according to the EC50value of four-parameter curve. Two-dimensional hydrogen-nitrogen correlation(2D1H-15N HSQC)spectrum of CGRP were acquired by NMR technique,and the binding of antibodies to the arginine of CGRP were analyzed through the disturbance of the antibodies to CGRP signals. Specific arginine modifications were detected by liquid chromatography-mass spectrum(LCMS) and NMR technique,and two arginine resonances were assigned on CGRP by correlating the rank order of the modification rate.ResultsThe antigen binding activities of two antibodies with CGRP(1-37),CGRP(19-37)and CGRP(25-37)showed dose-response relationships,and were fitted with four-parameter equation. However,there were no significant antigen binding with CGRP(1-18),CGRP(19-24)and CGRP(25-37)without C-terminal amide. The linear epitopes of both antibodies were located at the C-terminal of CGRP. The resonances of arginine ε-NH in 2D1H-15N HSQC spectrum disappeared in the presence of the control antibody;and the resonances appeared in the presence of the new antibody. The arginine R11 and R18 of CGRP could bind to the control antibody,but not to the new antibody. The NMR assignment for the arginine resonances were made by correlating the relative ranking of the modification rate where signals A and B arose from R11 ε-NH and R18 ε-NH respectively.ConclusionIn this study,the linear and conformational epitopes of new CGRP antibody and control antibody were identified based on the methods of ELISA and NMR,which may provide a theoretical basis for the design of the candidate therapeutic CGRP antibodies.

Matching strategy for patients with platelet transfusion refractoriness caused by compound antibodies against HLA and CD36 / 中国输血杂志

【Objective】 To search compatible and suitable platelets for platelet transfusion refractoriness (PTR) patient caused by compound antibodies against HLA and CD36. 【Methods】 ELISA method was used to detect the antibody against platelet antigens and the specificity of HLA-I antibody in PTR patients. The specificity of HLA-I antibody and corresponding epitopes of patients were analyzed using MATCH IT! and HLA Matchmaker software. The HLA genotype of both donor and patient was obtained by HLA-SSO method. Compatible or suitable donor platelets for PTR patients were searched through cross-reactive group (CREG) of HLA-I and HLA epitope-matched approach (Eplet). The matching degree was identified using monoclonal antibody-specific immobilization of platelet antigens (MAIPA) and the platelet suspension immunofluores-cence test (PIFT). Finally, the transfusion effect was evaluated according to the corrected count increment (CCI). 【Results】 Compound antibodies against both CD36 and HLA-I antigens were detected in two PTR patients, and their phenotype of CD36 was conformed to be type I deficient. Through LSA testing, high-frequency of HLA -I antibodies was found in these two patients, and the panel reactive antibody in patients 1 and 2 was 56% (54/96) and 53% (51/96), respectively. According to HLA-CREG and Eplet matching strategies, one donor of grade C-matching with patient 1 and one donor of grade D-matching with patient 2 were screened from the CD36 deficiency donor bank, respectively. And the selected donors avoided the antigen of HLA-I antibody epitope. These results of MAIPA and PIFT also confirmed that no immune response was detected between the patient and the donor. And a CCI of >4.5 within 24 hour of transfusion of compatible platelets was obtained in patient 2. 【Conclusion】 For PTR patients caused by HLA and CD36 compound antibodies, a combination strategy including serological cross-matching, HLA-CREG and Eplet approach should be used to select the CD36 deficient donor platelets which evaded the antigen corresponding to HLA-I antibodies and had the compatible HLA epitopes.

Viral selection pressure and CD4+T cell epitope in HLA-DRB1 * 11:01 of HCV infected patients / 中国输血杂志

【Objective】 HLA-DRB1 * 11:01, as a class HLA-Ⅱ gene, was reported to be associated with spontaneous clearance of HCV in Han and Li population. Our study was to investigate the effects of viral selection pressure and CD4+T cell epitope on the natural outcome of HCV infection in HLA-DRB1 * 11:01 positive infected patients. 【Methods】 The positive selection sites and population growth of E1E2 and NS3 genes of common HCV 6a in HLA-DRB1 * 11:01 positive and negative groups in Guangdong were respectively analyzed. The peptide library covering the conserved regions of common HCV genotypes was used to stimulate HCV spontaneous clearance group and chronic infection group using ELISPOT method. Reactive peptides were obtained according to the number of spot-forming cells per well and the frequency of occurrence in different groups. 【Results】 The positive selection sites (PSSs) of E1E2 and NS3 of common HCV 6a in HLA-DRB1 * 11:01 negative group were greater than those in HLA-DRB1 * 11:01 positive group. Furthermore, the number of PPSs in CD4+T cell peptide in HLA-DRB1 * 11:01 negative group were also greater than those in HLA-DRB1 * 11:01 positive group; Both groups of HCV 6a had a population growth in Guangdong, and the expansion trend of HLA-DRB1 * 11:01 negative group was significantly higher than that of HLA-DRB1 * 11 :01 positive group. Compared to HCV chronic infection group, the response rate of HCV spontaneous clearance group to five peptides (C-52 E2691-707, C-119 NS31545-1560, C-134 NS4A1669-1684, C-154 NS4B1912-1927, C-159 NS4B1929-1944) was higher. However, the HCV chronic infection group showed a higher response rate to two of the peptides(C-111 NS31497-1512, C-130 NS31650-1665). When HLA-DRB1 * 11:01 typing was considered, there was no significant difference in HCV-specific immune response generated by PBMCs between HLA-DRB1 * 11:01 positive and HLA-DRB1 * 11:01 negative groups. 【Conclusion】 This study revealed the relationship between viral selection pressure of HLA-DRB1 * 11:01 HCV infected persons and CD4+T cell antigen epitopes. At the same time, CD4+ T cell antigen epitopes of HCV pan-genotype were obtained, providing basic data for the development of T cell vaccine suitable for HCV pan-genotype.

Bioinformatics analysis of VP1 of Coxsackievirus A10 / 公共卫生与预防医学

Objective To predict and analyze the physicochemical properties, structural characteristics, and antigenic epitopes of viral protein (VP) VP1 of Coxsackievirus A10 (CV-A10) by bioinformatics methods. Methods The physicochemical properties and structural characteristics of CV-A10 VP1 were predicted by ProtParam, SOPMA, SWISS-MODEL, PDBsum, and ProSA-web. The antigenic epitopes of CV-A10 VP1 were predicted and analyzed by DNAstar, ABCpred, Bepipred 2.0, ElliPro, DiscoTope-2.0, NetMHCpan-4.1, NetMHCIIpan-4.0, Consurf, VaxiJen v.2.0, AllerTOP v.2.0, ToxinPred2, and IEDB immunogenicity. Results Bioinformatics analysis showed that CV-A10 VP1 was a basic, unstable, and hydrophilic protein, of which the secondary structure mainly consisted of random coil. The analysis revealed that CV-A10 VP1 had multiple potential B and T cell antigenic epitopes as well as a dominant antigenic epitope based on the potential epitope. Conclusion CV-A10 VP1 has multiple potential sites that induce specific humoral and cellular immunity, providing important support for its experimental identification, molecular epidemiological studies, and vaccine development.

Targets of chimeric antigen receptor T-cell in breast cancer and the application progress / 肿瘤研究与临床

Breast cancer is the most common malignant tumor in women. It is particularly important to seek targeted therapy other than surgery, chemoradiotherapy, endocrine therapy. With the continuous exploration of tumor immunotherapy, more and more therapeutic targets have been discovered. This paper reviews therapeutic targets of chimeric antigen receptor T-cell (CAR-T) and the application in breast cancer.

Preliminary immunological evaluation of Mycobacterium tuberculosis multicomponent protein vaccine candidates EPDPA015f and EPDPA015m / 中华微生物学和免疫学杂志

Objective:To preliminarily evaluate the immunogenicity and efficacy of two novel tuberculosis vaccine candidates (a fusion multicomponent protein EPDPA015f and a mixed multicomponent protein EPDPA015m) and to provide a new antigen combination for the development of tuberculosis vaccines.Methods:Recombinant plasmids for the expression of EPDPA015f and EPDPA015m proteins were constructed. Six-week-old BALB/c mice were immunized with EPDPA015f or EPDPA015m in combination with aluminium adjuvant (50 μg/mouse) for three times with an interval of 10 d. The mice were sacrificed 10 d after the last immunization to collect blood and spleen samples. Serum antibody titers and cytokine levels were measured by ELISA, Luminex technique and enzyme-linked immunospot assay (ELISPOT). Mycobacterial growth inhibition assay (MGIA) was used to detect the ability of mouse splenocytes to inhibit the growth of Mtb in vitro. One-way analysis of variance and t-test were used for statistical analysis. Results:Both EPDPA015f and EPDPA015m could induce the production of various cytokines and IgG antibodies at a high level. The levels of cytokines related to Th1 (IL-2, TNF-α, IFN-γ), Th2 (IL-4, IL-6, IL-10) and Th17 (IL-17) as well as other proinflammatory cytokines (GM-CSF, IL-12) were higher in the EPDPA015f group than in the adjuvant group ( P<0.05). The titer of IgG antibody induced by EPDPA015f was as high as 1∶4×10 6. The results of MGIA showed that the numbers of Mtb (lgCFU) in the PBS, adjuvant, EPDPA015f and EPDPA015m groups were 3.46±0.11, 3.51±0.06, 2.98±0.09 and 3.19±0.08, respectively. The number of colonies in the EPDPA015f group was the least as compared with that in the other three groups ( P<0.001, P<0.001, P<0.01). Conclusions:The vaccine candidate EPDPA015f could elicit more comprehensive and high-level cellular and humoral immune responses, and exhibited superior in vitro inhibitory activity against the growth of Mtb. EPDPA015f had the potential to be used as a preventive vaccine or a booster vaccine

Epitope spreading in autoimmune bullous diseases / 中华皮肤科杂志

Epitope spreading often occurs in patients with autoimmune bullous diseases (ABDs), resulting in exposure of more antigenic epitopes, aggravation or transformation of pre-existing diseases, or concurrence of other diseases. With the increase in the immunological evidence for epitope spreading, more and more scholars have realized that epitope spreading plays an important role in the development of ABDs. This review introduces the phenomenon of epitope spreading in ABDs from 4 aspects, including the concurrence of or transformation between different types of pemphigoid, different types of pemphigus, pemphigus and pemphigoid, as well as between ABDs and other skin diseases.

Immunogenicity of chimeric peptide gene of Xinjiang hemorrhagic fever virus glycoprotein / 国际生物医学工程杂志

Objective:To investigate the effects of different chimerism strategies and different immune ways on the two antigen-dominant regions of Xinjiang hemorrhagic fever virus (XHFV) glycoprotein.Methods:The 5' end was added or not added with interleukin-2 (IL-2) signal peptide and the general-purpose auxiliary T cell epitopes as different design strategies. GcⅠ and GcⅡ and the epitopes previously identified on GcⅠ (Gc 233-248, Gc 241-256 and Gc 281-296) were fused and constructed into the eukaryotic expression vector pVAX1 and the prokaryotic expression vector pET-28a. The recombinant prokaryotic plasmid transformed into E.coli BL21 was induced and purified, and the recombinant eukaryotes were extracted by indirect immunofluorescent assay. BALB/c mice were immunized by protein immunity, gene immunity, and DNA prime-protein boost immunity. The IgG antibody level was measured by ELISA. The immune effect was evaluated by the proliferation of T-lymphocytes and the content of cytokines in the spleen. Results:The results of double enzyme digestion and sequencing showed that eight recombinant plasmids were successfully constructed, and the recombinant eukaryotes were successfully expressed in vitro by fluorescence microscopy. After three times of immunization, the IgG level and the proliferation of T-lymphocytes in the spleen of mice in the experimental group were significantly higher than those in the control group ( P<0.01). The mass concentration test results of Th2 cytokines IL-4 and Th1 cytokines interferon-gamma (IFN-γ) revealed that the response of the DNA prime-protein boost immunity was biased to Th1. Conclusions:The multi-epitope chimeric vaccine of XHFV glycoprotein was successfully constructed, and the target antigen could be expressed effectively in vivo. The immune groups stimulated stronger humoral and cellular immune responses compared with the control group. Among them, the immune effect of pVAX1-ST(GcⅠe+GcⅡ) combined with recombinant protein r(GcⅠe+GcⅡ) was the best, and it is expected to be a new candidate vaccine for XHFV.

An immunoglobulin y that specifically binds to an in silico-predicted unique epitope of Zika virus non-structural 1 antigen

Objective: To identify unique immunogenic epitopes of Zika virus non-structural 1 (NS1) antigen and produce immunoglobulin Y (IgY) for potential use in he diagnosis of of Zika virus infection. Methods: Immunogenic epitopes were identified using in silico B-cell epitope prediction. A synthetic peptide analog of the predicted epitope was used to induce antipeptide IgY production in hens which was purified using affinity chromatography. Presence of purified IgY and its binding specificity were performed by gel electrophoresis and ELISA, respectively. Results: Out of the nine continuous epitopes identified, the sequence at position 193-208 (LKVREDYSLECDPAVI) was selected and used to produce anti-peptide IgY. The produced IgY was found to bind to the synthetic analog of the Zika virus NS1 immunogenic epitope but not to other flaviviruses and random peptides from other pathogens. Conclusions: In this study, we identified an immunogenic epitope unique to Zika virus that can be used to develop a serodiagnostic tool that specifically detect Zika virus infection.

Systematic mutational analysis of epitope-grafted ED3 immunogenicity reveals a DENV3-DENV4 bi-serospecific ED3 mutant

Objective: To identify the residue determinants of the serospecificity and sero-cross-reactivity of dengue virus (DENV) envelope protein domain 3 (ED3), which contains two major putative epitopes of DENV. Methods: We constructed ED3 from DENV3 (3ED3) and DENV4 (4ED3), and six epitope-grafted variants, where we transferred epitope 1 (L304I, K305D, V309M, and S310A) and/or epitope 2 (D383N, K384S, K387T, and N389H) of 4ED3 onto 3ED3 and vice-versa. Swiss albino mice aged 3-4 weeks were immunized against wildtype and epitope-grafted ED3 variants and anti-ED3 IgG antibody responses were determined using ELISA. Results: Mouse immunization using 3ED3 and 4ED3 generated serotype-specific antisera, as expected. Similarly, most epitopegrafted ED3s produced antisera serospecific to the template ED3 with little or no cross-recognition of ED3 of the serotype from which the epitopes were taken. These indicated that a mere grafting of the epitope was not sufficient to transfer serospecificity, contrary to our expectations. However, one epitope-grafted ED3 mutant, where epitope 1 of 3ED3 was grafted onto 4ED3 (4ED3epi1), generated antisera that was serospecific to both 4ED3 and 3ED3. Conclusions: The 4ED3epi1 is a chimeric ED3 that produces antisera possessing serospecificity to both 3ED3 and 4ED3 onto a common 4ED3 scaffold. The 4ED3epi1, therefore, provides a unique tool for analyzing serospecificity and sero-cross-reactivity in dengue. We believe that chimeric ED3 may provide a template for future recombinant ED3 possessing serospecificity of multiple DENVs onto a single scaffold and may pave a way developing tri-and/or tetravalent anti-DENV antisera.

Preparation and characterization of a recombinant poly-epitopic vaccine EgG1Y162-2 (4) against cystic echinococcosis based on the linker GSGGSG / 中国血吸虫病防治杂志

Objective To perform prokaryotic expression and preliminary characterization of the recombinant poly-epitope vaccine EgG1Y162-2 (4) against cystic echinococcosis. Methods The recombinant poly-epitope vaccine EgG1Y162-2 (4) against Echinococcus granulosus based on the linker GSGGSG was subjected to structural three-dimensional (3D) modeling using immunoinformatics to analyze the structural changes and evaluate the antigenicity of the vaccine. The pET30a-EgG1Y162-2 (4) recombinant plasmid was generated using double digestion with EcoR I and Sal I, and then transformed into competent cells. Following protein induction with isopropyl-β-D-thiogalactoside (IPTG), the prokaryotic expression proteins were characterized using Western blotting, and the antigenicity of the recombinant protein was analyzed using sera from cystic echinococcosis patients and health volunteers. Results The four EgG1Y162-2 proteins coupled by the 3D structure of the recombinant vaccine EgG1Y162-2 (4) presented independent and effective expression and good antigenicity. The highest protein expression was detected in the supernatant following induction of the recombinant plasmid pET30a-EgG1Y162-2 (4) by 0.2 mmol/L IPTG at 37 °C for 4 h, and a pure protein component was seen following elution with 60 mmol/L imidazole. Western blotting analysis of the recombinant multiepitope protein HIS-EgG1Y162-2 (4) showed a band at approximately 39 kDa, and this band was recognized by sera from cystic echinococcosis patients. Conclusion A recombinant poly-epitope vaccine EgG1Y162-2 (4) against cystic echinococcosis has been successfully constructed, which provides a preliminary basis for researches on recombinant multi-epitope vaccine against cystic echinococcosis.

Análisis in silico de un candidato a vacuna multi-epítopo contra viruela del mono usando vaculonogía reversa / In silico analysis of a multi-epitope vaccine candidate against monkey pox using reverse vaccinology

Introducción. La viruela del mono es una infección zoonótica con una tasa de transmisión global aumentada durante 2022. Actualmente, la enfermedad no tiene tratamientos específicos disponibles; por lo tanto, se puede lograr un enfoque preventivo a través de la inmunización. Objetivo. Diseño in sílico de una vacuna aplicando técnicas computacionales avanzadas utilizando una construcción de múltiples epítopos del M. virus. Materiales y métodos. Los antígenos se seleccionaron en base a informes sobre proteínas que provocan la activación de linfocitos T y B citotóxicos. Los ensayos inmunoinformáticos fueron antigenicidad, alergenicidad, toxicidad, afinidad de unión al complejo mayor de histocompatibilidad (CMH) y estimulación de IFN-γ. Resultados y discusión. Ocho epítopos de las proteínas M1R, ADN polimerasa, B6R y A35R de M. virus mostraron una respuesta significativa para las células inmunitarias. Se eligieron once epítopos con antigenicidad >0,3, no alergénicos y no tóxicos, de los cuales 4 presentaron alta afinidad por los linfocitos T, 4 generaron alta activación de linfocitos B y 3 se asociaron con resultados de activación de IFN-γ. La construcción in sílico del candidato vacunal de 509 aminoácidos con alta similitud topológica registró principalmente carga negativa, además de ser soluble con índice alifático >80%, estable y particular con activación CMH y alta afinidad molecular con TLR-3, y además presentó multiantigenicidad, similar a las vacunas generadas por esta metodología con M. tuberculosis e Influenza. La simulación de inyección de una dosis de la construcción molecular mostró la activación de las células plasmáticas auxiliares T durante aproximadamente 15 a 25 días y una alta expresión de IFN-γ e IL-2 durante ocho días. Conclusión. Estos resultados indican un excelente proceso de inmunización que podría potenciarse con dosis múltiples.

Introduction. Monkey pox is a zoonotic infection with an increased global transmission rate during 2022, denoted epidemiological trouble in public health. Currently, the disease has no specific treatments available; thus, a preventive approach can be achieved through immunization. Objective. was to design in silico a vaccine applying advanced computational techniques using a multi-epitope construct of the Monkeypox virus. Materials and methods. Antigens were selected based on reports about proteins that cause the activation of cytotoxic T and B lymphocytes. The immunoinformatics assays were antigenicity, allergenicity, toxicity, MHC binding affinity, and IFN-γ stimulation. Results and discussion. Eight epitopes of the M1R, DNA polymerase, B6R, and A35R proteins of the M. virus showed a significant response for immune cells. Eleven epitopes with antigenicity >0.3, non-allergenic and non-toxic were chosen, of which 4 presented high affinity to T lymphocytes, 4 generated high activation of B lymphocytes, and 3 were associated with IFN-γ activation results. The in silico construction of the 509-amino acid vaccine candidate with high topological similarity registered mainly a negative charge, in addition to being soluble with an aliphatic index >80%, stable and particular with MHC activation and high molecular affinity with TLR-3, and also presented multi-antigenicity, similar to vaccines generated by this methodology with M. tuberculosis and Influenza. One-dose injection simulation of the molecular construct showed activation of T helper plasma cells for about 15 to 25 days and high expression of IFN-γ and IL-2 for eight days. Conclusion. These results indicate an excellent immunization process that could be potentiated with multi-dosing.

Screening and identification of H-2 d-restricted T cell epitopes in fusion and attachment glycoproteins of Nipah virus by ELISPOT / 中华微生物学和免疫学杂志

Objective:To screen and identify H-2 d-restricted T cell epitopes in fusion (F) and attachment (G) glycoproteins of Nipah virus (NiV) in mice. Methods:The complete peptides (single peptide contains 15 amino acids, and 10 amino acids were repeated in the front and back peptides) derived from F and G antigens were mixed into peptide libraries. BALB/c mice were immunized with DNA vaccines expressing NiV F and G proteins alone and in combination. The full sequence peptide libraries of F and G antigens were mixed into peptide pools by matrix design, and spleen cells of immunized mice were collected and analyzed by IFN-γ ELISPOT assay to detect the dominant H-2 d-restricted epitope peptides. Results:Twelve dominant H-2 d-restricted peptides were screened from the F protein-specific peptide library and the 56th peptide produced the strongest reaction. Four dominant peptides were screened from the G protein-specific peptide library and the 72nd peptide produced the strongest reaction. Conclusions:In this study, 12 F antigen-specific and 4 G antigen-specific H-2 d restricted dominant T cell epitopes of NiV were screened and identified by IFN-γ ELISPOT, which could provide reference for immunological analysis of NiV and vaccine research.

Bullous pemphigoid and its immune-mediated comorbidities / 中华皮肤科杂志

Bullous pemphigoid (BP) can be comorbid with a variety of immune diseases, such as immune skin diseases (psoriasis, vitiligo, alopecia areata and various other immune bullous diseases) , immune digestive diseases (inflammatory bowel disease, primary biliary cirrhosis) , autoimmune thyroid diseases, autoimmune rheumatic diseases (rheumatoid arthritis, dermatomyositis, scleroderma and systemic lupus erythematosus) , immune renal diseases (immune nephropathy, renal allograft rejection) and acquired hemophilia A. The above comorbidities markedly affect the quality of life of and treatment options for patients. This review elaborates on currently reported immune diseases associated with BP and their concomitant mechanisms.

Construction of multi-epitope gene of periodic Brugia malayi and its expression in eukaryotic cells / 中华地方病学杂志

Objective:To construct a eukaryotic expression plasmid pcDNA3.1(+)-BmCPI502/BmGAPDH720 of periodic Brugia malayi cysteine protease inhibitor/glyceraldehyde 3-phosphate dehydrogenase (CPI502/GAPDH720) multi-epitope gene and observe its protein expression in Hela cells. Methods:Primers were designed according to the predicted gene sequences of T cell epitopes. The target gene fragment was amplified by reverse transcription (RT)-PCR using plasmid pGEM-T-CPI621 as template. The fragment was cloned into prokaryotic expression plasmid pET-28a(+) to construct prokaryotic expression plasmid pET28a(+)-BmCPI502. The BmCPI502 gene and BmGAPDH720 gene were amplified by RT-PCR, respectively. The gene fragments of pcDNA3.1(+), BmCPI502 and BmGAPDH720 were digested by double enzyme digestion and ligated with the target gene. The eukaryotic expression plasmid pcDNA3.1(+)-BmCPI502/BmGAPDH720 was constructed. The recombinant plasmid was transfected into Hela cells and verified by RT-PCR to obtain the desired target bands. The expression product was detected by sodium dodecyl sulfate polyacrylamide gelelectrophoresis (SDS-PAGE).Results:The recombinant plasmid pET28a(+)-BmCPI502 was obtained, and the 502 bp specific fragment was identified by enzyme digestion, which was in line with the expected value; the eukaryotic expression plasmid pcDNA3.1(+)-BmCPI502/BmGAPDH720 of the multi-epitope gene was successfully constructed, and the fragment size was in line with the expected value. The eukaryotic expression plasmid pcDNA3.1(+)-BmCPI502/BmGAPDH720 was transfected into Hela cells and the recombinant protein was stable expressed. SDS-PAGE analysis showed that the relative molecular weight ( Mr × 10 3) of the recombinant protein was about 50. Conclusions:The eukaryotic expression plasmid of pcDNA3.1(+)-BmCPI502/BmGAPDH720 of periodic Brugia malayi multi-epitope gene is successfully constructed, and the corresponding recombinant protein is obtained in eukaryotic cells. This study has laid a foundation for further study of the purification and biological activity of the recombinant protein.

Eukaryotic expression and antigen epitope prediction of the LRRC15 protein in excretory secretory antigens of Taenia solium cysticercus / 中国血吸虫病防治杂志

OBJECTIVE@#To conduct eukaryotic expression of the leucine-rich repeat containing 15 (LRRC15), a differentially expressed protein in excretory secretory antigens of Taenia solium cysticercus, and predict its antigen epitope.@*METHODS@#The molecular weight, stability, amino acid sequence composition, isoelectric point and T lymphocyte epitope of the LRRC15 protein were predicted using the bioinformatics online softwares ExPASy-PortParam and Protean. The full-length splicing primers were designed using PCR-based accurate synthesis, and the LRRC15 gene was synthesized. The recombinant pcDNA3.4-LRRC15 plasmid was constructed and transfected into HEK293 cells to express the LRRC15 protein. In addition, the LRRC15 protein was characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting.@*RESULTS@#The recombinant pcDNA3.4-LRRC15 plasmid was successfully constructed, which expressed the target LRRC15 protein with an approximately molecular weight of 70 kDa. Bioinformatics prediction with the ExPASy-PortParam software showed that LRRC15 was a hydrophilic protein, which was consisted of 644 amino acids and had a molecular weight of 69.89 kDa and an isoelectric point of 5.6. The molecular formula of the LRRC15 protein was C3073H4942N846O953S28 and had an instability coefficient is 50.3, indicating that LRRC15 was an instable protein. Bioinformatics prediction with the Protean software showed that the dominant T-cell antigen epitopes were located in 292 to 295, 353 to 361, 521 to 526 and 555 to 564 amino acids of the LRRC15 protein, and the T-cell antigen epitopes with a high hydrophilicity, good flexibility, high surface accessibility and high antigenicity index were found in 122 to 131, 216 to 233, 249 to 254, 333 to 343, 358 to 361, 368 to 372, 384 to 386, 407 to 412, 445 to 450, 469 to 481, 553 to 564, 588 to 594, 607 to 617 and 624 to 639 amino acids. Following transfection of the recombinant pcDNA3.4-LRRC15 plasmid into HEK293 cells, SDS-PAGE and Western blotting identified LRRC15 proteins in cell secretory culture media, cell lysis supernatants and sediments. The LRRC15-His fusion protein was purified from the cell culture medium, and SDS-PAGE identified a remarkable band at approximately 70 kDa, while Western blotting successfully recognized the band of the recombinant LRRC15 protein.@*CONCLUSIONS@#The eukaryotic expression and antigen epitope prediction of the LRRC15 protein in the excretory secretory antigens of T. solium cysticercus have been successfully performed, which provides insights into further understandings of its biological functions.