Establishment of a Tumor-bearing Mouse Model Stably Expressing Human Tumor Antigens Survivin and MUC1 VNTRs

The eukaryotic vectors VR1012 expressing survivin or 33 tandem repeats of human mucin 1(MUC1)(VNTRs),namely,VR1012-S and VR1012-VNTR(VNTR=variable number of tandem repeat),were constructed by cloning s...     

Injectable Biodegradable Chitosan‐Alginate 3D Porous Gel Scaffold for mRNA Vaccine Delivery

mRNA vaccines have proven to be more stable, effective, and specific than protein/peptide‐based vaccines in stimulating both humoral and cellular immune response. However, mRNA's fast degradation rate and low‐transfection efficiency in vivo impede its potential in vaccination. Recent research in gene delivery has focused on nonviral vaccine carriers and either implantable or injectable delivery systems to improve transgene expression in vivo. Here, an injectable chitosan‐alginate gel scaffold for the local delivery of mRNA vaccines is reported. Gel scaffold biodegradation rates and biocompatibility are quantified. Scaffold‐mediated mRNA in vivo transgene expression as well as ovalbumin antigen specific cellular and humoral immune responses are evaluated in vivo. Luciferase reporter protein expression resulting from mRNA lipoplex‐loaded gel scaffolds is five times higher than systemic injection. Compared to systemic injections of naked mRNA or mRNA:lipoplexes, elevated levels of T cell proliferation and IFN‐γ secretion are seen with in vivo scaffold‐mediated mRNA lipoplex delivery. Furthermore, a humoral response (ovalbumin antigen specific IgG levels) is observed as early as week 1 for scaffold‐mediated mRNA lipoplex delivery, while protein‐based immunization did not elicit IgG production until 2 weeks post‐injection. Results suggest that injectable scaffold mRNA vaccine delivery maybe a viable alternative to traditional nucleic acid immunization methods.     

Immunogenicity of Foot-and-Mouth Disease Virus Dendrimer Peptides: Need for a T-Cell Epitope and Ability to Elicit Heterotypic Responses

An approach based on a dendrimer display of B- and T-cell epitopes relevant for antibody induction has been shown to be effective as a foot-and-mouth disease (FMD) vaccine. B₂T dendrimers combining two copies of the major FMD virus (FMDV) type O B-cell epitope (capsid proteinVP1 (140–158)) covalently linked to a heterotypic T-cell epitope from non-structural protein 3A (21–35), henceforth B₂T-3A, has previously been shown to elicit high neutralizing antibody (nAb) titers and IFN-γ-producing cells in both mice and pigs. Here, we provide evidence that the B- and T-cell epitopes need to be tethered to a single molecular platform for successful T-cell help, leading to efficient nAb induction in mice. In addition, mice immunized with a non-covalent mixture of B₂T-3A dendrimers containing the B-cell epitopes of FMDV types O and C induced similarly high nAb levels against both serotypes, opening the way for a multivalent vaccine platform against a variety of serologically different FMDVs. These findings are relevant for the design of vaccine strategies based on B- and T-cell epitope combinations.     

Immunization Schedule of Liposomal Rabies Vaccine in Animals

The standard rabies vaccines recommended by WHO include Essen regimen, the Thai Red Cross two-site ID regimen and the eight-site ID regimen, and so on. The present schedules of rabies vaccine are all laborious and time consuming. We developed a new rabies vaccine with liposome as adjuvant(LipoRabV) and found that liposome could facilitate the inactivated rabies vaccine(RabV) to induce the more vigorous production of rabies virus neutra-lizing antibody(RVNA) in BALB/c mice and beagles. We established preliminary pre-and post-exposure prophylaxis schedules for LipoRabV. LipoRabV(0/14) could elicit similar RVNA level as RabV(0/7/28) by pre-exposure prophy-laxis schedules in mice and beagles. LipoRabV(0/3/14) could elicit higher RVNA level vs. RabV(0/3/7/14/28) in BALB/c. The data indicate that the three-shot liposome-enhanced rabies vaccine could achieve a higher protection rate(survival rate 56.2%) by post-exposure prophylaxis compared with that of the RabV group(survival rate 40.6%) in mice. The data also indicate that the three-inoculation liposome-enhanced rabies vaccine could achieve a survival rate of 80.0% vs. RabV(70.0%) by post-exposure prophylaxis in beagles. The results show that the immunization schedule for LipoRabV could be preliminarily determined at 0 and 14 d for pre-exposure prophylaxis and at 0, 3 and 14 d for post-exposure prophylaxis.     

Synthesis of 3-aminopropyl β-glycoside of sialyl-3′-lactose and derived neoglycoconjugates as a tumor vaccine prototype and artificial antigens for the control of immune response

Starting from the biotechnologically available trisaccharide sialyl-3′-lactose, representing the carbohydrate portion of the tumor-associated ganglioside GM3, the corresponding 3-aminopropyl β-glycoside (1) and 3-(4-maleimidobutanoylamino)propyl glycoside were synthesized. The reaction of the latter with a thiolated derivative of the Megathura crenulata hemocyanine (KLH) afforded a carbohydrate—protein conjugate, a tumor vaccine prototype containing about 330 trisaccharide ligands attached to KLH. N-Stearoylation of ligand 1 gave the model neoglycolipid for comparative study of the activity of mono-and polyvalent immunogens and the natural ganglioside GM3. A monovalent conjugate, in which ligand 1 is linked to biotin through an oligo(ethylene glycol) spacer and a polyvalent conjugate with a polyacrylamide carrier were also prepared. These conjugates are meant as covering antigens to assess the specificity and efficiency of the immune response in the ELISA assay. Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2016–2023, November, 2006.     

噬菌体展示肿瘤异性抗原表位的初步免疫活性研究

利用噬菌体展示技术将丝噬菌体（fd)基因8克隆入pKK233-3质粒中，将人的恶性黑色素瘤的抗原表位基因插入到修饰后的质粒载体中，制备了含有抗原表位的杂合噬菌体。利用纯化的表位抗原免疫小鼠，用间接ELISA方法采用双波长（450/630nm)动态检测抗体。结果表明，噬菌体-表位抗原刺激小鼠产生了抗体。抗体的含量随时间不断增加，到4周进达到高峰。小鼠脾淋巴细胞转化实验表明噬菌体-表位抗原产生了明显的淋巴细胞增殖反应，为研制肿瘤疫苗奠定了基础。     

Construction of Recombinant Modified Vaccinia Ankara （MVA） Expressing Hepatitis B Virus Surface Antigen

Introduction Despitetheexistenceofeffectiveprophylacticvac cinesagainstthehepatitisBvirus(HBV)formany years,HBVinfectionremainsaserioushealthproblem worldwide.Approximatetwobillionpeoplehavebeen infectedbyHBVanditisestimatedthatmorethan350millionofthemare…     

Synthesis of Muramyl dipeptide Analogs by Incorporation of 3,3,3-Trifluoroalanine

N-Acetylmuramyl-L-alanyl-D-isogl (Muramyl dipeptide, MDP), the smallestimmunoactive fragment of the cell wall peptidoglycans, which exhibits diverse biologicalactivities such as adjuvant property. enhancement of host defence ability againstmicrobial infection as wei] as antiviral and antitumor potency' =. In tJle last decades.studies on the synthesis of analogs and the relationship between structure and activity ofMDP analogs have emerged since its first synthesis in 1975" 3' '. Because of…     

Catalytic immunotherapy-photothermal therapy combination for melanoma by ferroptosis-activating vaccine based on artificial nanoenzyme

Tumor cell vaccine is a promising approach for cancer therapy to activate tumor immune, which can be achieved by tumor cells immunogenic cell death (ICD), converting in situ tumors into endogenous vaccination strategy, and ferroptosis has been proved to induce ICD occurrence. Ferroptosis is triggered by artificial nanoenzyme copper telluride mimicking peroxidase and glutathione oxidase, based on which the ferroptosis-activating vaccine (termed as CM CTNPs@OVA) was designed and established for catalytic immunotherapy. Owing to photothermal effect of copper telluride, photothermal therapy (PTT) was combined for an intensive cancer therapeutic effect. CM CTNPs@OVA was composed of solid mesoporous copper telluride nanoparticles, ovalbumin (OVA) loaded in mesoporous, and melanoma cell membrane coating surface. In in vitro and in vivo investigations, CM CTNPs@OVA, with particle size of 113.7 ± 1.7 nm, was certified to release copper ions for ferroptosis initiation, and OVA directly maturated dendritic cell (DC) as exogenous antigens extracellularly. ICD was then induced by ferroptosis pathway and PTT to release damage-associated molecular patterns for DC maturation and subsequent T cells recruitment. CM CTNPs@OVA-treated melanoma with exited inhibition rate, proving that the strategy of catalytic immunotherapy-PTT combination by ferroptosis-activating vaccine possessed massive potential for melanoma therapy based on nanoenzyme copper telluride.     

A label-free amperometric immunosenor based on multi-layer assembly of polymerized o-phenylenediamine and gold nanoparticles for determination of Japanese B encephalitis vaccine

A label-free amperometric immunosensor for fast and sensitive assay of Japanese B encephalitis vaccine is presented. Antiserum of Japanese B encephalitis were immobilized on bilayer nano-Au/o-phenylenediamine polymer film with deposited Prussian blue as an electronic mediator on the Pt electrode. The electrochemical behavior of the biosensor was studied with Fe^2+/3+ as probe on the Pt surface using cyclic voltammetry technique. The variation of amperometric response to the concentration of Japanese B encephalitis vaccine, the target antigen, was evaluated by cyclic voltammetry in PBS. The immunosensor showed a specific response to Japanese B encephalitis vaccine in the range 1.1 × 10⁻⁸ to 1.9 × 10⁻⁶ lg pfu/ml (pfu/ml is plaque forming unit and lg is common logarithm) with a detection limit of 6 × 10⁻⁹ lg pfu/ml. The correlation coefficient is 0.9955. The incubation time, incubation temperature, pH, reproducibility and stability of the immunosensor were also studied. The present work supplied a promising test method for biological products.