An O-Antigen Glycoconjugate Vaccine Produced Using Protein Glycan Coupling Technology Is Protective in an Inhalational Rat Model of Tularemia

There is a requirement for an efficacious vaccine to protect people against infection fromFrancisella tularensis, the etiological agent of tularemia. The lipopolysaccharide (LPS) ofF. tularensisis suboptimally protective against a parenteral lethal challenge in mice. To develop a more efficacious subunit vaccine, we have used a novel biosynthetic technique of protein glycan coupling technology (PGCT) that exploits bacterial N-linked glycosylation to recombinantly conjugateF. tularensisO-antigen glycans to the immunogenic carrier proteinPseudomonas aeruginosaexoprotein A (ExoA). Previously, we demonstrated that an ExoA glycoconjugate with two glycosylation sequons was capable of providing significant protection to mice against a challenge with a low-virulence strain ofF. tularensis. Here, we have generated a more heavily glycosylated conjugate vaccine and evaluated its efficacy in a Fischer 344 rat model of tularemia. We demonstrate that this glycoconjugate vaccine protected rats against disease and the lethality of an inhalational challenge withF. tularensisSchu S4. Our data highlights the potential of this biosynthetic approach for the creation of next-generation tularemia subunit vaccines.

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Mucosal Immunization with Live Attenuated Francisella novicida U112ΔiglB Protects against Pulmonary F. tularensis SCHU S4 in the Fischer 344 Rat Model

PLoS ONE ◽

10.1371/journal.pone.0047639 ◽

2012 ◽

Vol 7 (10) ◽

pp. e47639 ◽

Cited By ~ 17

Author(s):

Aimee L. Signarovitz ◽

Heather J. Ray ◽

Jieh-Juen Yu ◽

M. N. Guentzel ◽

James P. Chambers ◽

...

Keyword(s):

Rat Model ◽

Mucosal Immunization ◽

Francisella Novicida ◽

Fischer 344 ◽

Fischer 344 Rat ◽

Schu S4

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Global Analysis of Genes Essential forFrancisella tularensisSchu S4 GrowthIn Vitroand for Fitness during Competitive Infection of Fischer 344 Rats

Journal of Bacteriology ◽

10.1128/jb.00630-18 ◽

2019 ◽

Vol 201 (7) ◽

Cited By ~ 8

Author(s):

Philip M. Ireland ◽

Helen L. Bullifent ◽

Nicola J. Senior ◽

Stephanie J. Southern ◽

Zheng Rong Yang ◽

...

Keyword(s):

Francisella Tularensis ◽

Insertion Site ◽

Therapeutic Drug ◽

Content Type ◽

Fischer 344 ◽

A Genome ◽

Fischer 344 Rat ◽

Schu S4

ABSTRACTThe highly virulent intracellular pathogenFrancisella tularensisis a Gram-negative bacterium that has a wide host range, including humans, and is the causative agent of tularemia. To identify new therapeutic drug targets and vaccine candidates and investigate the genetic basis ofFrancisellavirulence in the Fischer 344 rat, we have constructed anF. tularensisSchu S4 transposon library. This library consists of more than 300,000 unique transposon mutants and represents a transposon insertion for every 6 bp of the genome. A transposon-directed insertion site sequencing (TraDIS) approach was used to identify 453 genes essential for growthin vitro. Many of these essential genes were mapped to key metabolic pathways, including glycolysis/gluconeogenesis, peptidoglycan synthesis, fatty acid biosynthesis, and the tricarboxylic acid (TCA) cycle. Additionally, 163 genes were identified as required for fitness during colonization of the Fischer 344 rat spleen. Thisin vivoselection screen was validated through the generation of marked deletion mutants that were individually assessed within a competitive index study against the wild-typeF. tularensisSchu S4 strain.IMPORTANCEThe intracellular bacterial pathogenFrancisella tularensiscauses a disease in humans characterized by the rapid onset of nonspecific symptoms such as swollen lymph glands, fever, and headaches.F. tularensisis one of the most infectious bacteria known and following pulmonary exposure can have a mortality rate exceeding 50% if left untreated. The low infectious dose of this organism and concerns surrounding its potential as a biological weapon have heightened the need for effective and safe therapies. To expand the repertoire of targets for therapeutic development, we initiated a genome-wide analysis. This study has identified genes that are important forF. tularensisunderin vitroandin vivoconditions, providing candidates that can be evaluated for vaccine or antibacterial development.

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Maintenance of carotid baroreflex function in advanced age in the rat

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1986.250.6.r1047 ◽

1986 ◽

Vol 250 (6) ◽

pp. R1047-R1051 ◽

Cited By ~ 4

Author(s):

J. Y. Wei ◽

D. Mendelowitz ◽

N. Anastasi ◽

J. W. Rowe

Keyword(s):

Arterial Pressure ◽

Rat Model ◽

Carotid Sinus ◽

Pressure Response ◽

Age Difference ◽

Base Line ◽

Fischer 344 ◽

Baroreflex Function ◽

Carotid Sinus Baroreflex ◽

Fischer 344 Rat

To evaluate the influence of age per se on the carotid sinus baroreceptors in the absence of hypertension and atherosclerosis, we employed the Fischer 344 rat model. In 14 adult (A, 6-9 mo) and 9 senescent (S, 24-26 mo) normotensive male Fischer 344 rats the left carotid sinus region was vascularly isolated with sinus nerve intact and perfused with oxygenated modified Kreb's solution. Simultaneous measurements of intrasinus pressure and femoral arterial pressure response were obtained during linear pressure increases (20-200 mmHg) in the vascularly isolated sinus. There was no age difference in base-line arterial pressure or heart rate. Both age groups demonstrated similar positive relations between basal femoral arterial pressure and the magnitude of the femoral pressure response to equivalent carotid sinus pressures. There were similar estimated sinus volumes at onset of systemic response (39 +/- 1, A; 39 +/- 1 microliter, S), time to initial systemic pressure response (9 +/- 1, A; 7 +/- 1 s, S), mean rates of femoral pressure decline (1.8 +/- 0.3, A; 2.1 +/- 0.3 mmHg/s, S), and return to base line (1.5 +/- 0.3, A; 1.4 +/- 0.3 mmHg/s, S) as well as magnitudes of systolic (25 +/- 3, A; 26 +/- 4 mmHg, S) and diastolic (21 +/- 2 A; 22 +/- 4 mmHg, S) pressure drops. Thus, in the Fischer 344 rat model of aging, which differs from the human in that it is not complicated by hypertension or atherosclerosis, carotid sinus baroreflex function appears to be well maintained in senescence.

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Conventional dose rate spatially-fractionated radiation therapy (SFRT) treatment response and its association with dosimetric parameters—A preclinical study in a Fischer 344 rat model

PLoS ONE ◽

10.1371/journal.pone.0229053 ◽

2020 ◽

Vol 15 (6) ◽

pp. e0229053

Author(s):

Judith N. Rivera ◽

Thomas M. Kierski ◽

Sandeep K. Kasoji ◽

Anthony S. Abrantes ◽

Paul A. Dayton ◽

...

Keyword(s):

Radiation Therapy ◽

Dose Rate ◽

Treatment Response ◽

Rat Model ◽

Preclinical Study ◽

Fischer 344 ◽

Conventional Dose ◽

Fischer 344 Rat ◽

Fractionated Radiation Therapy ◽

Fractionated Radiation

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Establishment of Fischer 344 rat model of ovarian cancer with lymphatic metastasis

Archives of Gynecology and Obstetrics ◽

10.1007/s00404-013-2937-2 ◽

2013 ◽

Vol 289 (1) ◽

pp. 149-154 ◽

Cited By ~ 2

Author(s):

Lingling Fan ◽

Yingtao Liu ◽

Xiaoyan Zhang ◽

Yu Kang ◽

Congjian Xu

Keyword(s):

Ovarian Cancer ◽

Rat Model ◽

Lymphatic Metastasis ◽

Fischer 344 ◽

Fischer 344 Rat

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Identification of an Attenuated Substrain of Francisella tularensis SCHU S4 by Phenotypic and Genotypic Analyses

Pathogens ◽

10.3390/pathogens10060638 ◽

2021 ◽

Vol 10 (6) ◽

pp. 638

Author(s):

Julie A. Lovchik ◽

Douglas S. Reed ◽

Julie A. Hutt ◽

Fangfang Xia ◽

Rick L. Stevens ◽

...

Keyword(s):

Francisella Tularensis ◽

Genomic Sequence ◽

Rabbit Model ◽

Battelle Memorial Institute ◽

Dose Equivalent ◽

Multiple Sources ◽

Tularensis Subsp ◽

Fischer 344 ◽

Fischer 344 Rat ◽

Schu S4

Pneumonic tularemia is a highly debilitating and potentially fatal disease caused by inhalation of Francisella tularensis. Most of our current understanding of its pathogenesis is based on the highly virulent F. tularensis subsp. tularensis strain SCHU S4. However, multiple sources of SCHU S4 have been maintained and propagated independently over the years, potentially generating genetic variants with altered virulence. In this study, the virulence of four SCHU S4 stocks (NR-10492, NR-28534, NR-643 from BEI Resources and FTS-635 from Battelle Memorial Institute) along with another virulent subsp. tularensis strain, MA00-2987, were assessed in parallel. In the Fischer 344 rat model of pneumonic tularemia, NR-643 and FTS-635 were found to be highly attenuated compared to NR-10492, NR-28534, and MA00-2987. In the NZW rabbit model of pneumonic tularemia, NR-643 caused morbidity but not mortality even at a dose equivalent to 500x the LD50 for NR-10492. Genetic analyses revealed that NR-10492 and NR-28534 were identical to each other, and nearly identical to the reference SCHU S4 sequence. NR-643 and FTS-635 were identical to each other but were found to have nine regions of difference in the genomic sequence when compared to the published reference SCHU S4 sequence. Given the genetic differences and decreased virulence, NR-643/FTS-635 should be clearly designated as a separate SCHU S4 substrain and no longer utilized in efficacy studies to evaluate potential vaccines and therapeutics against tularemia.

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