Erratum to “Comparative evaluation of the protective efficacy of two formulations of a recombinant Chlamydia abortus subunit candidate vaccine in a mouse model” [Vaccine 33 (2015) 1865–1872]

Infectious bursal disease (IBD), an immunosuppressive disease of young chickens, is caused by infectious bursal disease virus (IBDV). Novel variant IBDV (nVarIBDV), a virus that can evade immune protection against very virulent IBDV (vvIBDV), is becoming a threat to the poultry industry. Therefore, nVarIBDV-specific vaccine is much needed for nVarIBDV control. In this study, the VP2 protein of SHG19 (a representative strain of nVarIBDV) was successfully expressed using an Escherichia coli expression system and further purified via ammonium sulfate precipitation and size-exclusion chromatography. The purified protein SHG19-VP2-466 could self-assemble into 25-nm virus-like particle (VLP). Subsequently, the immunogenicity and protective effect of the SHG19-VLP vaccine were evaluated using animal experiments, which indicated that the SHG19-VLP vaccine elicited neutralization antibodies and provided 100% protection against the nVarIBDV. Furthermore, the protective efficacy of the SHG19-VLP vaccine against the vvIBDV was evaluated. Although the SHG19-VLP vaccine induced a comparatively lower vvIBDV-specific neutralization antibody titer, it provided good protection against the lethal vvIBDV. In summary, the SHG19-VLP candidate vaccine could provide complete immune protection against the homologous nVarIBDV as well as the heterologous vvIBDV. This study is of significance to the comprehensive prevention and control of the recent atypical IBD epidemic.

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Immunogenicity and protective efficacy of enterotoxigenic Escherichia coli (ETEC) total RNA against ETEC challenge in a mouse model

Scientific Reports ◽

10.1038/s41598-020-77551-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mandi Liu ◽

Yue Zhang ◽

Di Zhang ◽

Yun Bai ◽

Guomei Liu ◽

...

Keyword(s):

Escherichia Coli ◽

Mouse Model ◽

Immune Responses ◽

Protective Efficacy ◽

Enterotoxigenic Escherichia Coli ◽

Economic Losses ◽

Th2 Response ◽

Total Rna ◽

Etec Infection

AbstractEnterotoxigenic Escherichia coli (ETEC), an essential cause of post-weaning diarrhea (PWD) in piglets, leads to significant economic losses to the pig industry. The present study aims to identify the role of ETEC total RNA in eliciting immune responses to protect animals against ETEC infection. The results showed that the total RNA isolated from pig-derived ETEC K88ac strain effectively stimulated the IL-1β secretion of porcine intestinal epithelial cells (IPEC-J2). The mouse model immunized with ETEC total RNA via intramuscular injection (IM) or oral route (OR) was used to evaluate the protective efficiency of the ETEC total RNA. The results suggested that 70 μg ETEC total RNA administered by either route significantly promoted the production of the serum IL-1β and K88ac specific immunoglobulins (IgG, IgM, and IgA). Besides, the ETEC RNA administration augmented strong mucosal immunity by elevating K88ac specific IgA level in the intestinal fluid. Intramuscularly administered RNA induced a Th1/Th2 shift toward a Th2 response, while the orally administered RNA did not. The ETEC total RNA efficiently protected the animals against the ETEC challenge either by itself or as an adjuvant. The histology characterization of the small intestines also suggested the ETEC RNA administration protected the small intestinal structure against the ETEC infection. Particularly of note was that the immunity level and protective efficacy caused by ETEC RNA were dose-dependent. These findings will help understand the role of bacterial RNA in eliciting immune responses, and benefit the development of RNA-based vaccines or adjuvants.

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Comparative evaluation of oral and intranasal priming with replication-competent adenovirus 5 host range mutant (Ad5hr)-simian immunodeficiency virus (SIV) recombinant vaccines on immunogenicity and protective efficacy against SIVmac251

Vaccine ◽

10.1016/j.vaccine.2007.09.017 ◽

2007 ◽

Vol 25 (47) ◽

pp. 8021-8035 ◽

Cited By ~ 43

Author(s):

Qifeng Zhou ◽

Rachmat Hidajat ◽

Bo Peng ◽

David Venzon ◽

M. Kristine Aldrich ◽

...

Keyword(s):

Host Range ◽

Simian Immunodeficiency Virus ◽

Comparative Evaluation ◽

Protective Efficacy ◽

Recombinant Vaccines ◽

Immunodeficiency Virus ◽

Adenovirus 5

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A Host-Restricted Self-Attenuated Influenza Virus Provides Broad Pan-Influenza A Protection in a Mouse Model

Frontiers in Immunology ◽

10.3389/fimmu.2021.779223 ◽

2021 ◽

Vol 12 ◽

Author(s):

Minjin Kim ◽

Yucheol Cheong ◽

Jinhee Lee ◽

Jongkwan Lim ◽

Sanguine Byun ◽

...

Keyword(s):

Influenza Virus ◽

Mouse Model ◽

Neutralizing Antibodies ◽

Influenza A ◽

Protective Efficacy ◽

Influenza Viruses ◽

Cross Protection ◽

Infection Model ◽

Wild Type ◽

Group 1

Influenza virus infections can cause a broad range of symptoms, form mild respiratory problems to severe and fatal complications. While influenza virus poses a global health threat, the frequent antigenic change often significantly compromises the protective efficacy of seasonal vaccines, further increasing the vulnerability to viral infection. Therefore, it is in great need to employ strategies for the development of universal influenza vaccines (UIVs) which can elicit broad protection against diverse influenza viruses. Using a mouse infection model, we examined the breadth of protection of the caspase-triggered live attenuated influenza vaccine (ctLAIV), which was self-attenuated by the host caspase-dependent cleavage of internal viral proteins. A single vaccination in mice induced a broad reactive antibody response against four different influenza viruses, H1 and rH5 (HA group 1) and H3 and rH7 subtypes (HA group 2). Notably, despite the lack of detectable neutralizing antibodies, the vaccination provided heterosubtypic protection against the lethal challenge with the viruses. Sterile protection was confirmed by the complete absence of viral titers in the lungs and nasal turbinates after the challenge. Antibody-dependent cellular cytotoxicity (ADCC) activities of non-neutralizing antibodies contributed to cross-protection. The cross-protection remained robust even after in vivo depletion of T cells or NK cells, reflecting the strength and breadth of the antibody-dependent effector function. The robust mucosal secretion of sIgA reflects an additional level of cross-protection. Our data show that the host-restricted designer vaccine serves an option for developing a UIV, providing pan-influenza A protection against both group 1 and 2 influenza viruses. The present results of potency and breadth of protection from wild type and reassortant viruses addressed in the mouse model by single immunization merits further confirmation and validation, preferably in clinically relevant ferret models with wild type challenges.

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Comparison of ampicillin-sulbactam regimens simulating 1.5- and 3.0-gram doses to humans in treatment of Escherichia coli bacteremia in mice.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.39.4.930 ◽

1995 ◽

Vol 39 (4) ◽

pp. 930-936 ◽

Cited By ~ 5

Author(s):

P D Lister ◽

C C Sanders

Keyword(s):

Escherichia Coli ◽

Body Weight ◽

Mouse Model ◽

Protective Efficacy ◽

Clinical Isolates ◽

Human Pharmacokinetics ◽

Beta Lactamase ◽

E Coli ◽

Lethal Infection ◽

Experimentally Induced

A mouse model of bacteremia was used to compare the efficacies of 1.5- and 3.0-g intravenous doses of ampicillin-sulbactam. Seven strains of Escherichia coli producing various levels of TEM-1 beta-lactamase were used as the challenge isolates. These strains included six clinical isolates (MICs from 2/1 micrograms/ml [with 2 and 1 microgram/ml being the respective concentrations of ampicillin and sulbactam] to 32/16 micrograms/ml) with similar degrees of virulence in mice and a laboratory genetic transformant (E. coli AFE) which hyperproduces TEM-1 (MIC = 128/64 micrograms/ml). Human pharmacokinetics were simulated by injecting mice subcutaneously twice (1 h apart) with ampicillin-sulbactam at concentrations of 40 mg/kg of body weight (1.5 g) and 80 mg/kg (3.0 g). Against two clinical isolates for which ampicillin-sulbactam MICs were < or = 8/4 micrograms/ml, no difference was observed in either the rate or level of killing between the two doses, and both doses were 100% protective against lethal infection. Against the four clinical isolates for which ampicillin-sulbactam MICs were between 16/8 and 32/16 micrograms/ml, a slight delay in killing was noted with three of the strains. This delay was followed by a rapid 2- to 3-log drop in the level of bacteremia, and both doses of ampicillin-sulbactam were 100% protective against lethal septicemia. With strain AFE, no killing was observed with the 40-mg/kg dose compared with a 2-log killing with the 80-mg/kg dose. This difference in killing correlated with a decreased protective efficacy of the 40-mg/kg dose. These data suggest that the 1.5-g preparation of ampicillin-sulbactam is as effective as the 3.0-g dose in the treatment of experimentally induced E. coli bacteremia, as long as ampicillin-sulbactam MICs are 32/16 micrograms/ml or less.

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