• Title/Summary/Keyword: vaccine development

Search Result 454, Processing Time 0.03 seconds

Individual expression and processing of hepatitis C virus E1/E2 epitopes-based DNA vaccine candidate in healthy humans' peripheral blood mononuclear cells

  • Rola Nadeem;Amany Sayed Maghraby;Dina Nadeem Abd-Elshafy;Ahmed Barakat Barakat;Mahmoud Mohamed Bahgat
    • Clinical and Experimental Vaccine Research
    • /
    • v.12 no.1
    • /
    • pp.47-59
    • /
    • 2023
  • Purpose: The development and study of hepatitis C virus (HCV) vaccine candidates' individualized responses are of great importance. Here we report on an HCV DNA vaccine candidate based on selected envelope (E1/E2) epitopes. Besides, we assessed its expression and processing in human peripheral blood mononuclear cells (PBMCs) and in vivo cellular response in mice. Materials and Methods: HCV E1/E2 DNA construct (EC) was designed. The antigen expression of EC was assayed in PBMCs of five HCV-uninfected donors via a real-time quantitative polymerase chain reaction. Serum samples from 20 HCV antibody-positive patients were used to detect each individual PBMCs expressed antigens via enzyme-linked immunosorbent assay. Two groups, five Swiss albino mice each, were immunized with the EC or a control construct. The absolute count of lymph nodes' CD4+ and CD8+ T-lymphocytes was assessed. Results: Donors' PBMCs showed different levels of EC expression, ranging between 0.83-2.61-fold in four donors, while donor-3 showed 34.53-fold expression. The antigens expressed in PBMCs were significantly reactive to the 20 HCV antibody repertoire (all p=0.0001). All showed comparable reactivity except for donor-3 showing the lowest reactivity level. The absolute count % of the CD4+ T-cell significantly increased in four of the five EC-immunized mice compared to the control group (p=0.03). No significant difference in CD8+ T-cells % was observed (p=0.89). Conclusion: The inter-individual variation in antigen expression and processing dominance was evident, showing independence in individuals' antigen expression and reactivity levels to antibodies. The described vaccine candidate might result in a promising natural immune response with a possibility of CD4+ T-cell early priming.

New typhoid vaccine using sponge-like reduced protocol: development and evaluation

  • Rehab Bahy;Asmaa Gaber;Hamdallah Zedan;Mona Mabrook
    • Clinical and Experimental Vaccine Research
    • /
    • v.12 no.1
    • /
    • pp.70-76
    • /
    • 2023
  • Purpose: Typhoid remains a major health problem, especially in the developing world. Furthermore, the emergence of multidrug-resistant and extensively drug-resistant strains of Salmonella typhi added a sense of urgency to develop more effective typhoid vaccines, one of which is bacterial ghosts (BGs), prepared by both genetic and chemical means. The chemical method includes incubation with numerous agents for a short time at their minimum inhibitory or minimum growth concentrations. This study included the preparation of BGs by a sponge-like reduced protocol (SLRP). Materials and Methods: Critical concentrations of sodium dodecyl sulfate, NaOH, and H2O2 were used. Moreover, high-quality BGs were visualized by scanning electron microscope (SEM). Subculturing was used to confirm the absence of vital cells. Besides, the concentrations of the released DNA and protein were estimated spectrophotometrically. In addition, the integrity of cells was proved by visualizing Gram-stained cells using a light microscope. Furthermore, a comparison between the immunogenicity and safety of the prepared vaccine and the available whole-cell killed vaccine was established. Results: Improved preparation of high-quality BGs of S. typhi, visualized by SEM, revealed punctured cells with intact outer shells. Moreover, the absence of vital cells was confirmed by subculturing. At the same time, the release of respective amounts of proteins and DNA is another evidence of BGs' production. Additionally, the challenge test provided evidence that the prepared BGs are immunogenic and have the same efficacy as the whole cell vaccine. Conclusion: The SLRP provided a simple, economical, and feasible method for BGs preparation.

Acute interstitial nephritis with acute kidney injury after COVID-19 vaccination: a case report

  • Jimin Lim;Jin Hyuk Paek;Hyeong Chan Shin;Woo Yeong Park;Kyubok Jin;Misun Choe;Seungyeup Han;Yaerim Kim
    • Clinical and Experimental Vaccine Research
    • /
    • v.13 no.1
    • /
    • pp.68-71
    • /
    • 2024
  • In the context of the massive spread of coronavirus disease 2019 (COVID-19), the development of a COVID-19 vaccine is urgently needed. The Pfizer-BioNTech COVID-19 vaccine has been widely applied across global populations. Herein, we report a case of acute interstitial nephritis with acute kidney injury in a young healthy subject after administration of the COVID-19 vaccine. A 20-year-old man was admitted with abdominal discomfort and nausea. He had received the Pfizer-BioNTech COVID-19 vaccine 6 days before. At 9 days after vaccination, his kidney function was decreased, with serum creatinine levels of 1.8 mg/dL. Even with supportive care with hydration, his kidney function worsened, and he underwent a kidney biopsy. The pathology findings revealed diffuse interstitial infiltration of inflammatory cells, predominantly comprising lymphocytes, with preservation of the glomerulus. No abnormal findings were noted by immunofluorescence or electron microscopy. Based on a diagnosis of drug-related acute interstitial nephritis, we treated the patient with high-dose prednisolone. After administration of prednisolone, kidney function slowly improved. A close linkage between COVID-19 vaccination and acute interstitial nephritis should be considered in the clinic, despite the low incidence.

Control of Influenza: Live Vaccine Development

  • Seong, Baik-Lin
    • Proceedings of the PSK Conference
    • /
    • 2002.10a
    • /
    • pp.149-150
    • /
    • 2002
  • Despite various efforts on improving vaccines and antivirals, influenza epidemics continue to afflict many people, causing widespread morbidity and mortality in the young and the elderly. Since the discovery of the unusual 'cap-stealing'mechanism of transcription, significant advances were made on molecular aspects of influenza gene regulation. This provides new insights for developing new antiviral compounds. Reverse genetic technologies have also been advanced for generating recombinant chimeric viruses suitable for designing live vaccine. (omitted)

  • PDF