The Protective Role of Toll-Like Receptor Agonist Monophosphoryl Lipid A Against Vaccinated Murine Schistosomiasis

Two peptides derivate from Acinetobacter baumannii outer membrane protein K as vaccine candidates: a comprehensive in silico study

BACKGROUND

The lack of appropriate vaccines is an obstacle to the effective management of A. baumannii infections. Peptide vaccines offer an attractive and promising preventive strategy against A. baumannii.

OBJECTIVE

In this study, we identified specific T cell epitopes of A. baumannii outer membrane protein K (OMPK) using comprehensive bioinformatics and detailed molecular docking analysis.

METHODS

Both class-I and class-II T cell epitopes of A. baumannii OMPK were predicted by three tools namely IEDB, SYFPEITHI, and ProPred. The predicted epitopes were shortlisted based on several analyses including prediction scoring, clustering, exclusion of human similarity, considering immunogenicity and cytokine production, and removal of toxic and/or allergen epitopes. The epitopic peptides with high prediction scores and appropriate properties containing both class-I and class-II T cell epitopes were selected. Two of these class I/II epitopic peptides were chosen for molecular docking studies and assessing their physicochemical properties as vaccine candidates.

RESULTS

The results showed many T-cell epitopes of OMPK that could be evaluated for possible immunogenicity. Two of these epitopes (containing both class-I and II epitopes) had high prediction scores, were predicted by several tools, attached to several HLAs, and had the best docking score. They had different physicochemical properties and were conserved among Acinetobacter species.

DISCUSSION

We identified the A. baumannii OMPK high immunogenic class-I and class-II T cell epitopes and introduced two promising high immunogenic peptides as vaccine candidates. It is recommended to perform in vitro/in vivo investigation of these peptides to determine their true efficacy and efficiency.

Lepidium sativum and Its Biogenic Silver Nanoparticles Activate Immune Cells and Induce Apoptosis and Cell Cycle Arrest in HT-29 Colon Cancer Cells

There is an increased demand for plants with antioxidants and anticancer properties. Lepidium sativum L. is an edible plant with medical importance. In this study, we aimed to investigate the anticancer activity; antioxidant capacity and antibacterial impact of Lepidium sativum L. seed acetone extract (LSSAExt), alone and with its biogenic silver nanoparticles (AgNPs). LSSAExt-produced AgNPs were characterized using SEM, XRD and Vis/UV analysis. Biomolecules in LSSAExt and LSSAExt + AgNPs were explored utilizing FTIR. The ability of LSSAExt and LSSAExt + AgNPs to induce apoptosis and mitotic cell arrest in the HT-29 colon cancer cells, compared to normal and repeated cell division activated splenic cells was determined by florescent stains and flow cytometry. Antibacterial power was tested using well diffusion technique. LSSAExt and LSSAExt + AgNPs showed a good antibacterial impact. LSSAExt contains ROS, which could help in cancer cells apoptosis. LSSAExt and LSSAExt+AgNPs were not toxic to splenic cells and increased the rate of their cell division. LSSAExt and LSSAExt+AgNPs increased p53 expression and could arrest cell division of HT-29 colon cancer cells but not of normal fast dividing cells. LSSAExt and LSSAExt+AgNPs caused apoptosis in cancer cells rather than necrosis. In conclusion, acetone preparation of the edible plant L. sativum is a good antibacterial agent, good anticancer preparation at least against colon cancer as it is shown to be targeted, effective and can boost immune cells.