[In silico Design of a New Multi-Epitope Peptide-Based Vaccine Candidate Against Q Fever].

Novel types of the vaccines with high immunogenicity and low risks, including epitope-based vaccines, are sought. Among zoonotic disease, Q fever caused by Coxiella burnetii is an important target due to numerous outbreaks and the pandemic potential. Here we present a synthetic multi-epitope vaccine against Coxiella burnetii. This vaccine was developed using immunoinformatics approach. Antigenic proteins were studied, and five T cell epitopes were selected. Antigenicity, allergenicity, and toxicity of the selected epitopes were evaluated using the VaxiJen 2.0, AllerTOP, and ToxinPred servers, respectively. Selected epitopes were joined in a peptide sequence, with the cholera toxin В subunit (CTXB) as an adjuvant. The affinity of the proposed vaccine to MHCI and II molecules was measured in a molecular docking study. Resultant vaccine has high antigenicity, stability, and a half-life compatible with utilization in vaccination programs. In conclusion, the validated epitope sequences may be used as a potential vaccine to ensure protection against Q fever agent.

In Silico Design of a New Multi-Epitope Peptide-Based Vaccine Candidate Against Q Fever.

Novel types of the vaccines with high immunogenicity and low risks, including epitope-based vaccines, are sought. Among zoonotic disease, Q fever caused by Coxiella burnetii is an important target due to numerous outbreaks and the pandemic potential. Here we present a synthetic multi-epitope vaccine against Coxiella burnetii. This vaccine was developed using immunoinformatics approach. Antigenic proteins were studied, and five T cell epitopes were selected. Antigenicity, allergenicity, and toxicity of the selected epitopes were evaluated using the VaxiJen 2.0, AllerTOP, and ToxinPred servers, respectively. Selected epitopes were joined in a peptide sequence, with the cholera toxin B subunit (CTXB) as an adjuvant. The affinity of the proposed vaccine to MHC I and II molecules was measured in a molecular docking study. Resultant vaccine has high antigenicity, stability, and a half-life compatible with utilization in vaccination programs. In conclusion, the validated epitope sequences may be used as a potential vaccine to ensure protection against Q fever agent.

Design of a recombinant immunotoxin against the human granulocyte-colony stimulating factor receptor.

Immunotoxin is a new strategy for protein therapy of cancer. This engineered protein contains two parts, the immune part which is an antibody or cytokine, directed against the cancer cell receptor, and the toxin part consisting of a plant or bacterial toxin leading to apoptosis by protein synthesis inhibition. The knowledge of cell-surface receptor overexpression in cancer cells can help scientists to construct new anti-cancer agents. The granulocyte colony stimulating factor (G-CSF) receptor is expressed on the cell surface of some blood cancers such as acute myeloid leukemia (AML). Therefore, this receptor can be used as an immunotoxin for treatment of some cancers. The aim of this work was to design and produce DT-GCSF immunotoxin using truncated DT fused to G-CSF. For fusion protein construction, DT389 and G-CSF fragments, were amplified by PCR using specific primers. A flexible linker SerGly4SerMet (SG4SM) was used to fuse the PCR products by SOEing PCR procedure to achieve an appropriate fusion protein, and the fused fragment was subcloned into pET21b. The new construction (pET-DT389GCSF) was transformed into E. coli strain BL21 (DE3) and the expression of the construction was confirmed by SDS-PAGE and Western blotting techniques. The data demonstrated the expression and purity rates of DT389GCSF about 25% and 90%, respectively. This chimeric protein construction can be used as a new anti-AML drug, but its in vitro and in vivo biological activity should be analyzed.

Evaluation of a rapid detection for Coxsackievirus B3 using one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP).

Coxsackievirus B3 (CVB3) is a member of the genus Enterovirus within the family Picornaviridae and is an important pathogen of viral myocarditis, which accounts for more than 50% viral myocarditis cases. VP1 is major capsid protein that this region has a low homology in both amino acid and nucleotide sequences among Enteroviruses. Therefore we have chosen this region for designed a set of RT-LAMP primers for CVB3 detection. For this the total RNA was extracted from 24-h post infected-HeLa cells with complete cytopathic effect (CPE), and applied to a one-step reverse transcription loop-mediated isothermal amplification reaction (RT-LAMP) using CVB3-specific primers. The optimization of RT-LAMP reaction was carried out with three variables factors including MgSO4 concentration, temperature and time of incubation. Amplification was analyzed by using 2% agarose gel electrophoresis and ethidium bromide and SYBR Green staining. Our results were shown the ladder-like pattern of the VP1 gene amplification. The LAMP reaction mix was optimized and the best result observed at 4mM MgSO4 and 60°C for 90min incubation. RT-LAMP had high sensitivity and specificity for detection of CVB3 infection. This method can be used as a rapid and easy diagnostic test for detection of CVB3 in clinical laboratories.

Towards an understanding of marine fouling effects on the vortex-induced vibrations of circular cylinders: partial coverage issue.

The results of in-water vortex-induced vibration (VIV) experiments on circular cylinders artificially covered with barnacles are reported. The paper focusses on the effects of the partial coverage and the shape of the fouling elements. An artificial barnacle typical of marine fouling was synthesised using 3-D printing. Coverage ratios of 80, 50 and 30% were examined and the results compared with those from a smooth cylinder. The Reynolds number ranged from 5.8 × 103 to 6.6 × 104. The experimental results show that the fouling reduced the peak VIV amplitude, narrowed the synchronisation region and lowered the hydrodynamic force coefficients such as the coefficients of lift force RMS, the mean drag force and the fluctuating drag force RMS. The shape of the artificial barnacles had little effect on the maximum oscillation amplitude. The coverage ratio appeared to have a lower impact on the lift force than those on the amplitude and the frequency responses.

Enhancement of aspirin-induced gastric damage by cholestasis in rats.

In this study the severity of aspirin-induced gastric mucosal damage was investigated in rats with obstructive cholestasis. Cholestasis was induced by ligation and resection of the bile duct under general anesthesia. Two weeks after operation, the rats were fasted for 24 hours. Aspirin was administered orally in doses of 0, 128, 192, 266 and 335 mg/kg, and the animals were killed four hours after dosing. The dose of 266 mg/kg was chosen for a study of the time-dependency; other groups of animals were killed at time intervals of one, three, five, seven and nine hours after aspirin administration. The results showed that aspirin induces more severe gastric damage in bile duct resected rats compared with sham-operated and control animals. Salicylate levels of serums were also measured but there was no significant difference in serum salicylate levels between bile duct resected, sham-operated and control rats. It can be concluded that cholestasis can potentiate aspirin-induced gastric damage in rats.