Gene Editing/Gene Therapies: BIOREACTOR RECOMBINANT PRODUCTION OF SARS-COV-2 VIRUS ANTIGENS IN CHO CELL CLONES BY USING NEW UCOE LENTIVIRAL VECTOR SYSTEM

Background & Aim: The new UCOE models we have recently developed, tested on many cell groups (including mouse ES and human iPS cells) and human mAb recombinant production studies as well, shows a powerful resistance to DNA methylation- mediated silencing and provides a higher and stable transfection profile. By the urgent need of vaccine development for COVID-19 during the pandemic, in this study we aimed to produce a potential recombinant vaccine by using the new generation UCOEs models of our own design. Methods, Results & Conclusion(s): Existing new-generation UCOE models and standard plasmid vectors to be used as control group were provided. Then, the sequences related to the PCR method were amplified for sufficient stock generation and cloning experiments. Verification in the plasmid vector was carried out in gel electrophoresis. Transfection of 293T cells was performed with clone plasmids carrying antigen genes and plasmids carrying genetic information of lentivirus units for the production of lentiviral vectors. Afterwards, 293T cells produced lentiviral vectors carrying antigen genes. Harvesting of these vectors was carried out during 48th and 72nd hours. Afterwards, CHO cells were transduced with appropriate quantity of lentiviral vectors. Isolation and purification of targeted proteins from the relevant medium were performed by HPLC and Q-TOF methods. A part of the spike and nucleocapsid gene sequences of COVID-19 were firstly cloned into our UCOE models. These UCOEs plasmids were then transferred into 293T cells along with plasmids carrying the genes that will form the lentivirus vectors (LVs). After harvesting and calculation of LV vector titers, the cloned vectors were then transfected into the CHO cells which the targeted recombinant production of the antigen proteins will be carried out. Antigenic structures were then isolated from the culture medium of CHO cells in following days for confirmation. Using HPLC and qTOF mass spectrometer methods, these structures in the medium were confirmed to be the units of spike and nucleocapsid proteins of the COVID-19 virus. In order to produce large amount of the recombinant antigens, the culture was then carried out with bioreactors in liters. At the final stage, these recombinantly produced antigen proteins were tested on rats to measure their immunogenic responses, and the study recently been completed successfully as a potential recombinant vaccine against COVID-19.Copyright © 2023 International Society for Cell & Gene Therapy

Remitting Seronegative Symmetrical Synovitis with Pitting Oedema Following Administration of the Chadox1-S/NCOV-19 Coronavirus Vaccine.

Introduction: We describe a case of remitting seronegative symmetrical synovitis with pitting oedema (RS3PE) syndrome following administration of the ChAdOx1-S/nCoV-19 [recombinant] vaccine, suggesting a possible causal link. Case Description: A 72-year-old man presented to his general practitioner with swollen, oedematous hands and legs 2 weeks after receiving a coronavirus vaccine. He had raised inflammatory markers but remained systemically well. He was initially presumed to have cellulitis, but his symptoms persisted despite several courses of antibiotics. Deep vein thromboses, cardiac failure, renal failure and hypoalbuminaemia were ruled out. Upon Rheumatology review, he was diagnosed as having RS3PE syndrome with the Covid vaccine suspected of being an immunogenic trigger. Following initiation of steroid therapy, his symptoms improved dramatically, as is characteristic of RS3PE syndrome. Discussion: The pathophysiology of RS3PE is unclear. It is known to have various triggers and associations including infections, certain vaccines and malignancy. This case highlights that a coronavirus vaccine (ChAdOx1-S/nCoV-19 [recombinant] vaccine) is also a possible trigger. Factors that make the diagnosis likely include an acute onset of symptoms including pitting oedema in a typical distribution, age above 50, and unremarkable autoimmune serology. Other learning points from this case include the importance of antibiotic stewardship and the need to explore non-infectious causes of illness when antibiotics do not improve symptoms. Conclusion: The ChAdOx1-S/nCoV-19 [recombinant] vaccine is a possible trigger of RS3PE. However, the benefits of vaccines against coronavirus outweigh the risks in the majority of patients. LEARNING POINTS: This case demonstrates a possible link between the ChAdOx1-S/nCoV-19 [recombinant] vaccine and autoimmune conditions such as RS3PE.It is important to consider alternative diagnoses when antibiotic regimes fail to work.A barrier to accurate diagnosis includes an episodic approach, where a patient presents to multiple clinicians acutely rather than having a long-term, continuous relationship with a single multi-disciplinary team, where response to treatment can be monitored.

Herpes zoster – Part 3: Prevention of herpes zoster and post-herpetic neuralgia

Vaccination recommendations for the prevention of herpes zoster (HZ) aim to reactivate specific cell-mediated immunity towards the varicella/zoster virus. This specific immunity naturally declines with age but there are many factors that can accelerate this decline, including, most recently, the immune response induced by SARS-CoV-2. Two vaccines are available to date. A live attenuated vaccine (Zostavax®) licensed in 2006 and more recently a recombinant vaccine (Shingrix®). We present data on the efficacy of these two vaccines as well as on the relevant precautions and safety of use. © 2023 Elsevier Masson SAS Les recommandations vaccinales en matière de prévention du zona ont pour objectif de réactiver l'immunité à médiation cellulaire spécifique contre le virus varicelle-zona. Cette immunité spécifique décline naturellement avec l'âge mais nombreux sont les facteurs qui peuvent accélérer ce déclin dont récemment la réponse immunitaire induite par le SARS-CoV-2. Deux vaccins sont disponibles à ce jour : un vaccin vivant atténué (Zostavax®) homologué en 2006 et plus récemment un vaccin recombinant (Shingrix®). Nous présentons des données d'efficacité de ces deux vaccins ainsi que celles concernant leurs précautions d'emploi et la sécurité de leur utilisation. © 2023 Elsevier Masson SAS

Cases of Covid-19 in Patients Withi Mmune-Mediated Rheumatic Diseases after Vaccination against Sars-Cov-2 in Manaus-Amazon

Objectives: Immunization against SARS-CoV-2 is an effective strategy to reduce morbidity and mortality in the face of the COVID-19 pandemic. People with Immune-mediated Rheumatic Diseases (IMRD) also benefited from this campaign. However, there is a limited amount of data on the outcome of vaccination in these patients, in terms of those who were infected by the virus. This study had the objective to evaluate the rate of COVID-19 cases in patients with IMRD after vaccination against SARS-CoV-2. Method(s): Observational, longitudinal and ambidirectional study with follow-up of subgroups of patients with IMRD immunized with vaccines made available by the National Immunization Plan (inactivated adsorbed vaccine registered by the Instituto Butantan (IB), recombinant vaccines registered by Bio Manguinhos/ Fiocruz and by Janssen, and Pfizer/BioNTech). Sociodemographic data and questionnaires on flu syndrome, laboratory confirmation of infection and need for hospitalization and outcomes were collected and stored via an online platform. This study is associated to the SAFER Project from the Brazilian Society of Rheumatology and it was approved by the local Research Ethics Committee. Result(s): A total of 223 patients aged over 18 years, mean age 42.79 +/- 15.18 years, were included. All were within the inclusion/exclusion criteria, with 83% being female. The main IMRD included were systemic lupus erythematosus (39%) and rheumatoid arthritis (33.6%). After the 1st dose, 1.45% of patients had COVID-19, 50% sought health services (emergency care), without the need for hospitalization and after the 2nd dose, 1.5% had the disease, of which none sought health services, required hospitalization or had a negative outcome. After the 3rd dose,: 2.9%were infected with SARS-CoV-2 one month later, 15.6% two to three months later and 5.5% four to six months later, all with laboratory confirmation;only 4% presenting any serious complication;there were no deaths. After the 4th dose, 9.1%of patients had COVID-19, of which 40%were hospitalized, without the need for assisted ventilation;half of these patients had a serious complication, but there no deaths. Conclusion(s): In this study, we observed the effectiveness of the vaccine in preventing severe cases of COVID-19 and complications of SARS-CoV-2 infection.

Covax-19/Spikogen: The first exclusively Australian-developed human vaccine in four decades

Introduction/Aim: The development of safe and effective vaccines is crucial to conquering the COVID-19 pandemic. Recombinant proteins represent the best understood and reliable approach to pandemic vaccine delivery with well-established safety;however, they face challenges in design, structural characterisation, manufacture, potency testing and ensuring adequate immunogenicity. Method(s): Our team used in silico structural modelling to design a vaccine based on a stabilised spike protein extracellular domain (ECD). The insect cell expressed recombinant spike ECD was formulated with Vaxine's proprietary Advax-CpG55.2 adjuvant. Result(s): The vaccine known as Covax-19 or SpikoGen induced high titers of antibody and memory T-cells which translated to protection against SARS-CoV-2 infection in hamsters, ferrets, and aged monkeys. Despite numerous challenges along the journey, clinical trials in Iran during a major wave of delta variant infection confirmed SpikoGen vaccine was 78% effective in reducing risk of severe disease and with no evidence of vaccine-associated thrombosis, myocarditis, or sudden death, receiving marketing approval under emergency use authorisation in Iran on 6 October 2021. This made it the first recombinant spike-protein vaccine in the world to be approved, and the first Australian-developed human vaccine to receive marketing approval in four decades. Since approval millions of doses have been administered and additional trials in Australia and Iran have confirmed its effectiveness as a booster to prevent waning immunity, as well as its safety and effectiveness in children from the age of 5 years. The ongoing Australian and overseas clinical trial program is focussed on gaining better understanding the effect of dosing intervals on vaccine immunogenicity, gathering additional data on use as a booster, and development of new variant formulations. Conclusion(s): Covax-19/Spikogen is safe and effective adjuvanted recombinant protein vaccine.

Le zona – Partie 3 : la prévention du zona et des névralgies post-zostériennes

Résumé Les recommandations vaccinales en matière de prévention du zona ont pour objectif de réactiver l'immunité à médiation cellulaire spécifique contre le virus varicelle-zona. Cette immunité spécifique décline naturellement avec l'âge mais nombreux sont les facteurs qui peuvent accélérer ce déclin dont récemment la réponse immunitaire induite par le SARS-CoV-2. Deux vaccins sont disponibles à ce jour : un vaccin vivant atténué (Zostavax®) homologué en 2006 et plus récemment un vaccin recombinant (Shingrix®). Nous présentons des données d'efficacité de ces deux vaccins ainsi que celles concernant leurs précautions d'emploi et la sécurité de leur utilisation. Summary Vaccination recommendations for the prevention of herpes zoster (HZ) aim to reactivate specific cell-mediated immunity towards the varicella/zoster virus. This specific immunity naturally declines with age but there are many factors that can accelerate this decline, including, most recently, the immune response induced by SARS-CoV-2. Two vaccines are available to date. A live attenuated vaccine (Zostavax®) licensed in 2006 and more recently a recombinant vaccine (Shingrix®). We present data on the efficacy of these two vaccines as well as on the relevant precautions and safety of use.

Coronavirus disease 2019 vaccination in patients with chronic kidney diseases.

Patients with chronic kidney disease (CKD) are at high risk for coronavirus disease 2019 (COVID-19). Government agencies or learned societies in many countries recommend prioritizing patients with CKD for COVID-19 vaccines. The immune response rate to the COVID-19 vaccines is lower in hemodialysis patients and kidney transplant recipients compared with that in healthy individuals, and increasing the number of vaccinations each member of these population may improve their immune response rate. There was no significant difference in the incidence of adverse reactions after vaccination between patients with CKD and healthy controls. Patients with stable CKD should be vaccinated against COVID-19 unless there were contraindications to vaccination. The mRNA vaccines, inactivated vaccines, and recombinant protein subunit vaccines are all safe for patients with CKD. Patients with CKD treated with rituximab or high-dose glucocorticoid need to weigh the benefits and risks before vaccination, and COVID-19 vaccines can be given when rituximab treatment ends for more than 6 months or after glucocorticoid reduction.Copyright © 2021 by the Chinese Medical Association.

Delayed hypersensitivity reaction to hyaluronic acid dermal filler following ChAdOx1-S recombinant vaccine against coronavirus: Case report

Case report Background: Delayed hypersensitivity reactions to hyaluronic acid fillers are usually self-limiting and uncommon, and spontaneous resolution is frequent. These are presumably T-lymphocyte- mediated reactions that can be caused by flu-like infections and vaccinations. A delayed hypersensitivity reaction after hyaluronic acid filler following the mRNA vaccine against coronavirus has already been described in the literature. We wish to present a case that followed the ChAdOx1-s recombinant COVID-19 vaccine produced by Oxford/ AstraZeneca. Case report: Female patient, 61 years old, submitted to filling of the nasojugal sulcus and nasolabial fold with 1 ml of cross-linked hyaluronic acid -15 mg/ml and after 5 days filling in the lips with 1 ml of cross-linked hyaluronic acid -12 mg/ml, dermatological office, under aseptic technique and using cannulas. It evolved with ecchymosis on the lips and nasolabial folds, with spontaneous resolution after about a week. Sixteen weeks after the procedure, she received the first dose of the ChAdOx1-s recombinant COVID-19 vaccine, and 11 weeks later, the second dose. After 30 days of the 2nd vaccine dose, asymptomatic nodules appeared distributed in the upper and lower portions of nasolabial folds, in melomentonian grooves, in the supralabial region, in the upper and lower lip in the right and left lateral portions and in the infralabial region in the left lateral portion, coinciding with the topographies of the populated areas. Ultrasonographic evaluation with Doppler confirmed these findings. At the time, she denied fever or previous infectious signs or symptoms. Previously, the patient had already been submitted to the filling of the nasojugal and nasolabial folds with a hyaluronic acid-based filler (1 ml), 29 months before the current procedure, without intercurrences. After the appearance of the nodules, she underwent treatment with prednisone 40mg for 15 days, with total weaning after another 15 days, in addition to the use of levoceritizine 5 mg daily for 20 days, with partial reduction in the size of the nodules. Due to aesthetic complaints on the part of the patient, an intralesional injection of hyaluronidase was scheduled, but it was not performed at the request of the patient herself, who opted for expectant management and clinical treatment. In October 2021, the patient reported that the nodules had involuted and in December 2021 she remained asymptomatic, referring to resorption of the entire filler.

Current Status and Prospects of Vaccines based on DDS Technology.

The development of DDS technology has contributed critically to the unprecedentedly rapid requirement for vaccines against COVID-19. LNP-based mRNA vaccines represent a subset of DDS emerging DDS technology. Despite the groundbreaking nature of these vaccines, they are yet to be perfected and as such, new technologies are being developed to optimize these vaccines. This review will focus on exploring one of the modalities of recombinant protein vaccines and will introduce various findings on the enhancement of vaccine efficacy using antigen modification technologies, including VLPs and Fc-fusion proteins, and adjuvant improvements.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.

Current Status and Prospects of Vaccines based on DDS Technology.

The development of DDS technology has contributed critically to the unprecedentedly rapid requirement for vaccines against COVID-19. LNP-based mRNA vaccines represent a subset of DDS emerging DDS technology. Despite the groundbreaking nature of these vaccines, they are yet to be perfected and as such, new technologies are being developed to optimize these vaccines. This review will focus on exploring one of the modalities of recombinant protein vaccines and will introduce various findings on the enhancement of vaccine efficacy using antigen modification technologies, including VLPs and Fc-fusion proteins, and adjuvant improvements.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.

Current Status and Prospects of Vaccines based on DDS Technology.

The development of DDS technology has contributed critically to the unprecedentedly rapid requirement for vaccines against COVID-19. LNP-based mRNA vaccines represent a subset of DDS emerging DDS technology. Despite the groundbreaking nature of these vaccines, they are yet to be perfected and as such, new technologies are being developed to optimize these vaccines. This review will focus on exploring one of the modalities of recombinant protein vaccines and will introduce various findings on the enhancement of vaccine efficacy using antigen modification technologies, including VLPs and Fc-fusion proteins, and adjuvant improvements.Copyright © 2022, Japan Society of Drug Delivery System. All rights reserved.

Immunogenicity and Safety of a Combined Intramuscular/Intranasal Recombinant Spike Protein COVID-19 Vaccine (RCP) in Healthy Adults Aged 18 to 55 Years Old: A Randomized, Double-Blind, Placebo-Controlled, Phase I Trial.

Objectives: This study aimed to determine the safety and immunogenicity of a combined intramuscular/intranasal recombinant spike protein COVID-19 vaccine (RCP). Methods: We conducted a randomized, double-blind, placebo-controlled, phase I trial. Three vaccine strengths were compared with an adjuvant-only preparation. It included two intramuscular and a third intranasal dose. Eligible participants were followed for adverse reactions. Specific IgG, secretory IgA, neutralizing antibodies, and cell-mediated immunity were assessed. Results: A total of 153 participants were enrolled (13 sentinels, 120 randomized, 20 non-randomized open-labeled for IgA assessment). No related serious adverse event was observed. The geometric mean ratios (GMRs) and 95% CI for serum neutralizing antibodies compared with placebo two weeks after the second injection were 5.82 (1.46-23.13), 11.12 (2.74-45.09), and 20.70 (5.05-84.76) in 5, 10, and 20 µg vaccine groups, respectively. The GMR for anti-RBD IgA in mucosal fluid two weeks after the intranasal dose was 23.27 (21.27-25.45) in the 10 µg vaccine group. The humoral responses were sustained for up to five months. All vaccine strengths indicated a strong T-helper 1 response. Conclusion: RCP is safe and creates strong and durable humoral and cellular immunity and good mucosal immune response in its 10 µg /200 µL vaccine strengths. Trial registration: IRCT20201214049709N1.

Recent Progress in Recombinant Influenza Vaccine Development Toward Heterosubtypic Immune Response.

Flu, a viral infection caused by the influenza virus, is still a global public health concern with potential to cause seasonal epidemics and pandemics. Vaccination is considered the most effective protective strategy against the infection. However, given the high plasticity of the virus and the suboptimal immunogenicity of existing influenza vaccines, scientists are moving toward the development of universal vaccines. An important property of universal vaccines is their ability to induce heterosubtypic immunity, i.e., a wide immune response coverage toward different influenza subtypes. With the increasing number of studies and mounting evidence on the safety and efficacy of recombinant influenza vaccines (RIVs), they have been proposed as promising platforms for the development of universal vaccines. This review highlights the current progress and advances in the development of RIVs in the context of heterosubtypic immunity induction toward universal vaccine production. In particular, this review discussed existing knowledge on influenza and vaccine development, current hemagglutinin-based RIVs in the market and in the pipeline, other potential vaccine targets for RIVs (neuraminidase, matrix 1 and 2, nucleoprotein, polymerase acidic, and basic 1 and 2 antigens), and deantigenization process. This review also provided discussion points and future perspectives in looking at RIVs as potential universal vaccine candidates for influenza.

Expression and Immunogenicity of SARS-CoV-2 Virus-Like Particles based on Recombinant Truncated HEV-3 ORF2 Capsid Protein.

COVID-19 is an emerging disease that poses a severe threat to global public health. As such, there is an urgent demand for vaccines against SARS-CoV-2, the virus that causes COVID-19. Here, we describe a virus-like nanoparticle candidate vaccine against SARS-CoV-2 produced by an E. coli expression system. The fusion protein of a truncated ORF2-encoded protein of aa 439~608 (p170) from hepatitis E virus CCJD-517 and the receptor-binding domain of the spike protein from SARS-CoV-2 were expressed, purified and characterized. The antigenicity and immunogenicity of p170-RBD were evaluated in vitro and in Kunming mice. Our investigation revealed that p170-RBD self-assembled into approximately 24 nm virus-like particles, which could bind to serum from vaccinated people (p < 0.001) and receptors on cells. Immunization with p170-RBD induced the titer of IgG antibody vaccine increased from 14 days post-immunization and was significantly enhanced after a booster immunization at 28 dpi, ultimately reaching a peak level on 42 dpi with a titer of 4.97 log10. Pseudovirus neutralization tests showed that the candidate vaccine induced a strong neutralizing antibody response in mice. In this research, we demonstrated that p170-RBD possesses strong antigenicity and immunogenicity and could be a potential candidate for use in future SARS-CoV-2 vaccine development.

Reactogenicidad de la vacuna de ARNm BNT162b2 (Pfizer-BioNTech) frente a COVID-19 en trabajadores de un hospital de tercer nivel

OBJECTIVE: To analyze the local and systemic reactions that appeared after the first and second dose of the BNT162b2 vaccine against COVID‑19 (Pfizer- BioNTech) in a sample of workers from a tertiary hospital, and to identify the  factors related to greater vaccine reactogenicity. METHOD: A self-administered questionnaire was used to interview 291 workers  from a tertiary hospital who received the BNT162b2 vaccine against COVID-19  between January and March 2021. The questionnaire included questions about  the sociodemographic variables of the participants, previous COVID-19  infection, and local and systemic reactions after the first and second dose of  the vaccine. RESULTS: The most common adverse reaction was soreness at the injection site, which was reported more frequently after the first dose of the  vaccine. The systemic reactions evaluated were reported more frequently after the second dose of the vaccine. Women, younger adults, and  subjects with a prior COVID-19 infection reported increased reactogenicity. Furthermore, high reactogenicity after the first dose was found  to be related to a higher number of adverse reactions after the second dose of  the vaccine. CONCLUSIONS: The distribution of reactogenicity in the present study is consistent with the data reported in previous studies on the BNT162b2 vaccine, especially in terms of its association with the participants'  characteristics. These findings could facilitate the identification of people at a  higher risk of developing high reactogenicity to the vaccine, thereby making it  possible to anticipate the appearance of adverse reactions and plan for their  treatment. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved. OBJETIVO: Analizar las reacciones locales y sistémicas aparecidas tras la  primera y segunda dosis de la vacuna BNT162b2 (Pfizer-BioNTech) frente a  COVID-19 en una muestra de trabajadores de un hospital de tercer nivel, e  identificar los factores relacionados con una mayor reactogenicidad a la  vacuna.Método: Se empleó un cuestionario autoadministrado para entrevistar a 291  trabajadores de un hospital de tercer nivel que recibieron la vacuna BNT162b2  frente a COVID-19 entre enero y marzo de 2021. El cuestionario incluyó  preguntas acerca de las variables sociodemográficas de los participantes,  infección previa de COVID-19 y las reacciones locales y sistémicas tras la  primera y segunda dosis de la vacuna. RESULTADOS: La reacción más comúnmente informada fue el dolor en el lugar  de la inyección, siendo más frecuente tras la primera dosis de la vacuna. Las  reacciones sistémicas evaluadas se informaron con mayor frecuencia tras la  segunda dosis de la vacuna. Las mujeres, los adultos más jóvenes y las  personas con una infección previa por COVID-19 notificaron una mayor  reactogenicidad. Además, una alta reactogenicidad tras la primera dosis estuvo relacionada con un mayor número de reacciones adversas tras la segunda  dosis de la vacuna. CONCLUSIONES: La distribución de la reactogenicidad en el presente estudio es  consistente con los datos reportados en los estudios realizados  con la vacuna  BNT162b2, especialmente en términos de asociación con las características de  los participantes. Estos hallazgos pueden facilitar la identificación de personas  con mayor probabilidad de presentar una alta reactogenicidad a la vacuna,  permitiéndonos anticipar su aparición y tratamiento.

Neutralising Antibodies in Healthcare Workers after Two Doses of Covishield Vaccine at Three Months and Six Months: A Single-centre Observational Study

Introduction: The emergence of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) as a pandemic has put the global population at risk for its infection. It has also led to an accelerated effort to develop vaccines that can mitigate progression to severe infections at a minimum. The ambiguity about existence of antibodies in the human serum poses problem in formulating public health policies like suitable interval between doses of vaccines, appropriate time for vaccinating population, post natural infection, necessity of booster doses along with single dose. Aim: To estimate neutralising antibody level following vaccination of Healthcare Workers (HCWs) after three months and six months respectively. Materials and Methods: This was a prospective observational study performed in Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka, India after Institutional Ethics Committee (IEC) approval from January 2021 to February 2022. The study was conducted in 304 HCWs in the institute who had received two doses of Recombinant ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield). 41 HCWs who were naturally infected with SARS-CoV-2 either before or after vaccination were also included. These participants were then subjected to IgG neutralising antibody titer estimation at three months and six months, postvaccination. Results: The study included 304 eligible HCWs. Majority of the participants belonged to the age group of 31-40 years (35.9%). Majority of the study participants were females (51%). Of the 304 participants, 263 were uninfected and 41 participants had been infected before and after vaccination. At the six month follow-up, it was observed that all but one HCW had seroconverted with majority of the participants showing more than 60% antibody level. Participants in the age group of 31-40 years showed the highest level and this observation was found to be statistically significant. Conclusion: Neutralising antibody response in HCWs is a key indicator of the efficacy of the vaccination program for Coronavirus Disease-2019 (COVID-19) in India.

Review: Vaccine Guidelines for Older Adults

Vaccines are important for everyone, but they’re critical for adults older than 65 years.

SARS-CoV-2 Subunit Virus-like Vaccine Demonstrates High Safety Profile and Protective Efficacy: Preclinical Study.

Public health threat coming from a rapidly developing COVID-19 pandemic calls for developing safe and effective vaccines with innovative designs. This paper presents preclinical trial results of "Betuvax-CoV-2", a vaccine developed as a subunit vaccine containing a recombinant RBD-Fc fusion protein and betulin-based spherical virus-like nanoparticles as an adjuvant ("Betuspheres"). The study aimed to demonstrate vaccine safety in mice, rats, and Chinchilla rabbits through acute, subchronic, and reproductive toxicity studies. Along with safety, the vaccine demonstrated protective efficacy through SARS-CoV-2-neutralizing antibody production in mice, rats, hamsters, rabbits, and primates (rhesus macaque), and lung damage and infection protection in hamsters and rhesus macaque model. Eventually, "Betuvax-CoV-2" was proved to confer superior efficacy and protection against the SARS-CoV-2 in preclinical studies. Based on the above results, the vaccine was enabled to enter clinical trials that are currently underway.

Development of a Genetically Engineered Bivalent Vaccine against Porcine Epidemic Diarrhea Virus and Porcine Rotavirus.

Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that causes acute diarrhea, vomiting, dehydration, and a high mortality rate in neonatal piglets. In recent years, PEDV has been associated with co-infections with other swine enteric viruses, including porcine rotavirus (PoRV), resulting in increased mortality among newborn piglets. In this paper, we developed a bivalent vaccine against PEDV and PoRV by constructing a recombinant PEDV encoding PoRV VP7 (rPEDV-PoRV-VP7). The recombinant virus was constructed by replacing the entire open reading frame 3 (ORF3) in the genome of an attenuated PEDV strain YN150 with the PoRV VP7 gene using reverse genetic systems. Similar plaque morphology and replication kinetics were observed in Vero cells with the recombinant PEDV compared to the wild-type PEDV. It is noteworthy that the VP7 protein could be expressed stably in rPEDV-PoRV-VP7-infected cells. To evaluate the immunogenicity and safety of rPEDV-PoRV-VP7, 10-day-old piglets were vaccinated with the recombinant virus. After inoculation, no piglet displayed clinical symptoms such as vomiting, diarrhea, or anorexia. The PoRV VP7- and PEDV spike-specific IgG in serum and IgA in saliva were detected in piglets after rPEDV-PoRV-VP7 vaccination. Moreover, both PoRV and PEDV neutralizing antibodies were produced simultaneously in the inoculated piglets. Collectively, we engineered a recombinant PEDV expressing PoRV VP7 that could be used as an effective bivalent vaccine against PEDV and PoRV.

Latest progress and prospect of development of COVID-19 vaccine

The emerging Corona virus Disease 2019 (COVID-19) pandemic poses a massive crisis to global public health. World Health Organization (WHO) declared the global pandemic of COVID-19 on March 11, 2020. The progress of 2019- nCoV vaccines cover nearly all forms of current vaccine research, including inactivated vaccine, recombinant protein vaccine, viral vector-based vaccine, nucleic-acid vaccine and live attenuated vaccine, as well as the vaccine design based on novel concepts such as reverse vaccinology and vaccinomics. This article reviews the COVID-19 vaccines in de¬velopment and clinical trials as well as the challenge in vaccine development.