Regular and booster vaccination with inactivated vaccines enhance the neutralizing activity against Omicron variant both in the breakthrough infections or vaccinees

Abstract Given increased rates of breakthrough infection, German and other national authorities recommend heterologous booster vaccinations for Ad26.COV.2 vaccinated individuals, although data on immunogenicity and reactogenicity are lacking. We therefore recruited fifteen individuals who received the Ad26.COV.2 vaccination followed by a heterologous booster vaccination using the mRNA-vaccine BNT162b2. Immune response included SARS-CoV-2 spike-specific IgG, neutralizing activity as well as Spike-specific CD4 and CD8 T cells. Reactogenicity was self-reported using a questionnaire. We show that induction of specific immunity was poor after one dose of Ad26.COV.2. Heterologous boosting with BNT162b2 led to a significant increase in spike-specific IgG, neutralizing antibodies and CD4 and CD8 T cells. Heterologous boosting was well tolerated with more frequent systemic adverse events after the first dose. Thus, our data support current recommendations for heterologous booster-vaccination to optimize specific immunity and protection against SARS-CoV-2 infection in Ad26.COV.2-vaccinated individuals.

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Sequential immunization with SARS-CoV-2 RBD vaccine induces potent and broad neutralization against variants in mice

Virology Journal ◽

10.1186/s12985-021-01737-3 ◽

2022 ◽

Vol 19 (1) ◽

Author(s):

Shuo Song ◽

Bing Zhou ◽

Lin Cheng ◽

Weilong Liu ◽

Qing Fan ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Booster Dose ◽

Booster Vaccination ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Inactivated Vaccine ◽

Wild Type ◽

Broadly Neutralizing Antibodies ◽

Vaccination Strategies ◽

Inactivated Vaccines

AbstractThe current COVID-19 pandemic caused by constantly emerging SARS-CoV-2 variants still poses a threat to public health worldwide. Effective next-generation vaccines and optimized booster vaccination strategies are urgently needed. Here, we sequentially immunized mice with a SARS-CoV-2 wild-type inactivated vaccine and a heterologous mutant RBD vaccine, and then evaluated their neutralizing antibody responses against variants including Beta, Delta, Alpha, Iota, Kappa, and A.23.1. These data showed that a third booster dose of heterologous RBD vaccine especially after two doses of inactivated vaccines significantly enhanced the GMTs of nAbs against all SARS-CoV-2 variants we tested. In addition, the WT and variants all displayed good cross-immunogenicity and might be applied in the design of booster vaccines to induce broadly neutralizing antibodies.

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Review on Immersion Vaccines for Fish: An Update 2019

Microorganisms ◽

10.3390/microorganisms7120627 ◽

2019 ◽

Vol 7 (12) ◽

pp. 627 ◽

Cited By ~ 6

Author(s):

Jarl Bøgwald ◽

Roy A. Dalmo

Keyword(s):

Immune System ◽

Low Frequency ◽

Booster Vaccination ◽

Small Fish ◽

Efficient Delivery ◽

Low Frequency Ultrasound ◽

Inactivated Vaccines ◽

Multiple Puncture ◽

Positively Charged ◽

Frequency Ultrasound

Immersion vaccines are used for a variety of aquacultured fish to protect against infectious diseases caused by bacteria and viruses. During immersion vaccination the antigens are taken up by the skin, gills or gut and processed by the immune system, where the resulting response may lead to protection. The lack of classical secondary responses following repeated immersion vaccination may partly be explained by the limited uptake of antigens by immersion compared to injection. Administration of vaccines depends on the size of the fish. In most cases, immersion vaccination is inferior to injection vaccination with regard to achieved protection. However, injection is problematic in small fish, and fry as small as 0.5 gram may be immersion vaccinated when they are considered adaptively immunocompetent. Inactivated vaccines are, in many cases, weakly immunogenic, resulting in low protection after immersion vaccination. Therefore, during recent years, several studies have focused on different ways to augment the efficacy of these vaccines. Examples are booster vaccination, administration of immunostimulants/adjuvants, pretreatment with low frequency ultrasound, use of live attenuated and DNA vaccines, preincubation in hyperosmotic solutions, percutaneous application of a multiple puncture instrument and application of more suitable inactivation chemicals. Electrostatic coating with positively charged chitosan to obtain mucoadhesive vaccines and a more efficient delivery of inactivated vaccines has also been successful.

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Effectiveness of vaccines produced by the Federal State-Financed Institution “ARRIAH” against topical genotype VII Newcastle disease viruses

Veterinary Science Today ◽

10.29326/2304-196x-2021-1-36-44-51 ◽

2021 ◽

Vol 1 (1) ◽

pp. 44-51

Author(s):

S. V. Frolov ◽

N. V. Moroz ◽

I. A. Chvala ◽

V. N. Irza

Keyword(s):

Russian Federation ◽

Newcastle Disease ◽

Main Tool ◽

Booster Vaccination ◽

Vaccination Schedule ◽

Federal State ◽

Live Vaccines ◽

Inactivated Vaccines ◽

The Russian Federation ◽

Genotype Vii

In 2019, the situation regarding Newcastle disease in the Russian Federation worsened radically due to the spread of NDV subgenotype VII-L throughout the country from the Primorsky Krai to the Kursk Oblast. As a result, 17 infected settlements with backyard farms where unvaccinated poultry was kept were registered. In this study, immunogenicity of the vaccines produced by the FGBI “ARRIAH”, as well as the effectiveness of various vaccination schedules to prevent genotype VII NDVs, relevant for the Russian Federation, was studied. It is known that the currently circulating ND agent is significantly more virulent compared to the viruses isolated in previous years, and it is able to bypass the immunity provided by live vaccines. Test results demonstrated that the vaccines against genotype VII NDVs produced by the FGBI “ARRIAH” are highly immunogenic, which allows to effectively prevent the disease when using them as part of a standard vaccination schedule. A 2-dose vaccination schedule using live vaccine from the La Sota strain as well as the “complete” vaccination schedule using inactivated vaccines provides immunity in 100% of chicks. The use of live vaccines in a single- and double-dose vaccination schedules prevents mortality and clinical disease in poultry, but does not prevent virus replication, while the addition of an inactivated vaccine to the immunization schedule does prevent the replication of the virulent virus. Thus, the use of domestically produced live and inactivated vaccines, primarily the ones containing the La Sota strain, with the following control of the immunity level and booster vaccination, if required, is the main tool for the disease control.

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