Design of multi-epitope vaccine candidate based on OmpA, CarO and ZnuD proteins against multi-drug resistant Acinetobacter baumannii.

Acinetobacter baumannii has been identified as a major cause of nosocomial infections. Acinetobacter infections are often difficult to treat with multidrug resistant phenotypes. One of the most effective ways to combat infectious diseases is through vaccination. In this study, an attempt was made to select the most protective and potent immunostimulatory epitopes based on the epitope-rich domains of the ZnuD, OmpA and CarO proteins of Acinetobacter baumannii to design a vaccine that can protect against this infection. After predicting the epitope of B- and T-cells, seven antigenic regions of three proteins CarO, ZnuD and OmpA, were selected. These regions were bound by a GGGS linker. The binding affinity and molecular interactions of the vaccine with the immune receptors TLR2 and TLR4 were studied using molecular docking analysis. This vaccine design was subjected to in silico immune simulations using C-ImmSim. The designed vaccine was highly antigenic, non-allergenic and stable. TLR2 and TLR4 were selected to analyze the ability of the modeled chimeric protein to interact with immune system receptors. The results showed strong interaction between the designed protein vaccine with TLR2 (-18.8 kcal mol-1) and TLR4 (-15.1 kcal mol-1). To verify the stability of the interactions and the structure of the designed protein, molecular dynamics (MD) simulations were performed for 200 ns. Various analyses using MD showed that the protein structure is stable alone and in interaction with TLR2 and TLR4. The ability of the vaccine candidate protein to stimulate the immune system to produce the necessary cytokines and antibodies against Acinetobacter baumannii was also demonstrated by the ability of the protein designed using the C-ImmSim web server to induce an immune response. Therefore, the designed protein vaccine may be a suitable candidate for in vivo as well as in vitro studies against Acinetobacter baumannii infections.

Introduction of protein vaccine candidate based on AP65, AP33, and α-actinin proteins against Trichomonas vaginalis parasite: an immunoinformatics design.

BACKGROUND: Trichomonas vaginalis is the most common nonviral sexually transmitted disease (STI) worldwide. Vaccination is generally considered to be one of the most effective methods of preventing infectious diseases. Using AP65, AP33 and α-actinin proteins, this research aims to develop a protein vaccine against Trichomonas vaginalis. METHODS: Based on the B-cell and T-cell epitope prediction servers, the most antigenic epitopes were selected, and with the necessary evaluations, epitope-rich domains of three proteins, AP65, AP33, and α-actinin, were selected and linked. Subsequently, the ability of the vaccine to interact with toll-like receptors 2 and 4 (TLR2 and TLR4) was assessed. The stability of the interactions was also studied by molecular dynamics for a duration of 100 nanoseconds. RESULTS: The designed protein consists of 780 amino acids with a molecular weight of 85247.31 daltons. The results of the interaction of the vaccine candidate with TLR2 and TLR4 of the immune system also showed that there are strong interactions between the vaccine candidate protein with TLR2 (-890.7 kcal mol-1) and TLR4 (-967.3 kcal mol-1). All parameters studied to evaluate the stability of the protein structure and the protein-TLR2 and protein-TLR4 complexes showed that the structure of the vaccine candidate protein is stable alone and in complex with the immune system receptors. Investigation of the ability of the designed protein to induce an immune response using the C-ImmSim web server also showed that the designed protein is capable of stimulating B- and T-cell lymphocytes to produce the necessary cytokines and antibodies against Trichomonas vaginalis. CONCLUSIONS: Overall, our vaccine may have potential protection against Trichomonas vaginalis. However, for experimental in vivo and in vitro studies, it may be a good vaccine candidate.

Effect of crocin and quercetin supplementation in cryopreservation medium on post-thaw human sperm quality.

Biochemical and physical changes during the cryopreservation process adversely affect sperm function required for fertilization. Recently, many studies have been conducted to find effective pre-freezing treatments to limit these damages. The present study aimed to investigate the effects of pre-freezing treatment with quercetin and crocin, individually or in combination, on sperm parameters after thawing procedure. For this, semen samples from 20 normozoospermic men were collected and then each sample was divided into five equal parts: 1. fresh group 2. frozen-thawed group without addition of antioxidants 3. frozen-thawed group containing 1 mM crocin, 4. frozen-thawed group containing 50 µM quercetin, and 5. frozen-thawed group containing a combination of 1 mM crocin and 50 µM quercetin. Pre-cryopreservation and post-thaw sperm motility, morphology, viability, DNA fragmentation, reactive oxygen species [1] (ROS) levels, and mitochondrial membrane potential [2] (MMP) were investigated. Cryopreservation significantly reduced sperm quality. Both crocin and quercetin individually improved sperm progressive motility, decreased ROS levels, reduced DNA fragmentation, and marginally increased MMP, though crocin seems to be more successful in protecting sperm quality. More interestingly, the combined addition of crocin and quercetin to the sperm-freezing medium did not show positive effects on sperm quality. Crocin and quercetin may play a role in mitigating the cryopreservation-induced injury to sperm.

Effects of FTY720 on Neural Cell Behavior in Two and Three-Dimensional Culture and in Compression Spinal Cord Injury.

Introduction: The present study aimed to evaluate the effects of FTY720 as a neuromodulatory drug on the behaviors of neural stem/progenitor cells (NS/PCs) in two-dimensional (2-D) and three-dimensional (3-D) cultures and in spinal cord injury (SCI). Methods: The NS/PCs isolated from the ganglionic eminence of the 13.5-day old embryos were cultured as free-floating spheres. The single cells obtained from the second passage were cultured in 96-well plates without any scaffold (2-D) or containing PuraMatrix (PM, 3-D) or were used for transplantation in a mouse model of compression SCI. After exposure to 0, 10, 50, and 100 nanomolar of FTY720, the survival, proliferation, and migration of the NS/PCs were evaluated in vitro using MTT assay, neurosphere assay, and migration assay, respectively. Moreover, the functional recovery, survival and migration capacity of transplanted cells exposure to 100 nanomolar FTY720 were investigated in SCI. Results: Cell survival and migration capacity increased after exposure to 50 and 100 nanomolar FTY720. In addition, higher doses of FTY720 led to the formation of more extensive and more neurospheres. Although this phenomenon was similar in both 2-D and 3-D cultures, PM induced better distribution of the cells in a 3-D environment. Furthermore, co-administration of FTY720 and NS/PCs 7 days after SCI enhanced functional recovery and both survival and migration of transplanted cells in the lesion site. Conclusions: Due to the positive effects of FTY720 on the behavior of NS/PCs, using them in combination therapies can be an appealing approach for stem cell therapy in CNS injury.

Local delivery of fingolimod through PLGA nanoparticles and PuraMatrix-embedded neural precursor cells promote motor function recovery and tissue repair in spinal cord injury.

Spinal cord injury (SCI) is a devastating clinical problem that can lead to permanent motor dysfunction. Fingolimod (FTY720) is a sphingosine structural analogue, and recently, its therapeutic benefits in SCI have been reported. The present study aimed to evaluate the therapeutic efficacy of fingolimod-incorporated poly lactic-co-glycolic acid (PLGA) nanoparticles (nanofingolimod) delivered locally together with neural stem/progenitor cells (NS/PCs) transplantation in a mouse model of contusive acute SCI. Fingolimod was encapsulated in PLGA nanoparticles by the emulsion-evaporation method. Mouse NS/PCs were harvested and cultured from embryonic Day 14 (E14) ganglionic eminences. Induction of SCI was followed by the intrathecal delivery of nanofingolimod with and without intralesional transplantation of PuraMatrix-encapsulated NS/PCs. Functional recovery, injury size and the fate of the transplanted cells were evaluated after 28 days. The nanofingolimod particles represented spherical morphology. The entrapment efficiency determined by UV-visible spectroscopy was approximately 90%, and the drug content of fingolimod loaded nanoparticles was 13%. About 68% of encapsulated fingolimod was slowly released within 10 days. Local delivery of nanofingolimod in combination with NS/PCs transplantation led to a stronger improvement in neurological functions and minimized tissue damage. Furthermore, co-administration of nanofingolimod and NS/PCs not only increased the survival of transplanted cells but also promoted their fate towards more oligodendrocytic phenotype. Our data suggest that local release of nanofingolimod in combination with three-dimensional (3D) transplantation of NS/PCs in the acute phase of SCI could be a promising approach to restore the damaged tissues and improve neurological functions.

Effects of neural stem cell-derived extracellular vesicles on neuronal protection and functional recovery in the rat model of middle cerebral artery occlusion.

Stroke imposes a long-term neurological disability with limited effective treatments available for neuronal recovery. Transplantation of neural stem cells (NSCs) is reported to improve functional outcomes in the animal models of brain ischemia. However, the use of cell therapy is accompanied by adverse effects, so research is growing to use cell-free extracts such as extracellular vesicles (EVs) for targeting brain diseases. In the current study, male Wistar albino rats (20 months old) were subjected to middle cerebral artery occlusion (MCAO). Then, EVs (30 µg) were injected at 2 hours after stroke onset via an intracerebroventricular (ICV) route. Measurements were done at day 7 post-MCAO. EVs administration reduced lesion volume and steadily improved spontaneous locomotor activity. EVs administration also reduced microgliosis (ionized calcium-binding adaptor molecule 1 (Iba1)+ cells) and apoptotic (terminal-deoxynucleotidyl transferase mediated nick end labelling [TUNEL]) positive cells and increased neuronal survival (neuronal nuclear (NeuN)+ cells) in the ischemic boundary zone (IBZ). However, it had no effect on neurogenesis within the sub-ventricular zone (SVZ) but decreased cellular migration toward the IBZ (doublecortin (DCX)+ cells). The results of this study showed neuroprotective and restorative mechanisms of NSC-EVs administration, which may offer new avenues for therapeutic intervention of brain ischemia. SIGNIFICANCE OF THE STUDY: Based on our results, EVs administration can effectively reduce microglial density and neuronal apoptosis, thereby steadily improves functional recovery after MCAO. These findings provide the beneficial effect of NSC-EVs as a new biological treatment for stroke.

Regulation of adiponectin gene expression in adipose tissue by thyroid hormones

Available experimental data suggest that adiponectin and thyroid hormones have biological interaction in vivo. However, the effects of thyroid hormones on adipose adiponectin gene expression in thyroid dysfunction are unclear. We induced hyper- (HYPER) and hypothyroidism (HYPO) by daily administration of a 12 mg/l of levothyroxine and 250 mg/l of methimazole in drinking water of rats, respectively, for 42 days. The white adipose tissues and serum sample were taken on days 15, 28, 42 and also 2 weeks after treatment cessation. Analysis of adiponectin gene expression was performed by real-time PCR and 2−ÄÄct method. The levels of adipose tissue adiponectin mRNA in the HYPO rats were decreased during the 6-week treatment when compared to control rats (<0.05) and were increased significantly 2 weeks after HYPO cessation (P < 0.05). This decline in adiponectin gene expression occurred in parallel with a decrease in T3, T4, fT3 and fT4 concentrations (P < 0.05). In opposite to HYPO rats, adipose adiponectin gene expression was increased in HYPER rats during the 6-week treatment in parallel with an increase the thyroid hormones concentrations (P < 0.05), and its expression was decreased 2 weeks after HYPER cessation (P < 0.05). Adiponectin gene expression levels showed significant negative correlations with concentrations of LDL (HYPO; r = −0.806, P = 0.001 and HYPER; r = −0.749, P = 0.002), triglyceride (HYPO; r = −0.825, P = 0.001 and HYPER; r = −0.824, P = 0.001) and significant positive correlations with concentrations of glucose (HYPO; r = 0.674, P = 0.004 and HYPER; r = 0.866, P = 0.001) and HDL (HYPO; r = 0.755, P = 0.001 and HYPER; r = 0.839, P = 0.001). The current study provides evidence that adiponectin gene expression in adipose tissue is regulated by thyroid hormones at the translation level and that lipid and carbohydrate disturbances in a patient with thyroid dysfunction may be, in part, due to adiponectin gene expression changes (AU)

Regulation of adiponectin gene expression in adipose tissue by thyroid hormones.

Available experimental data suggest that adiponectin and thyroid hormones have biological interaction in vivo. However, the effects of thyroid hormones on adipose adiponectin gene expression in thyroid dysfunction are unclear. We induced hyper- (HYPER) and hypothyroidism (HYPO) by daily administration of a 12 mg/l of levothyroxine and 250 mg/l of methimazole in drinking water of rats, respectively, for 42 days. The white adipose tissues and serum sample were taken on days 15, 28, 42 and also 2 weeks after treatment cessation. Analysis of adiponectin gene expression was performed by real-time PCR and 2(-ΔΔct) method. The levels of adipose tissue adiponectin mRNA in the HYPO rats were decreased during the 6-week treatment when compared to control rats (<0.05) and were increased significantly 2 weeks after HYPO cessation (P < 0.05). This decline in adiponectin gene expression occurred in parallel with a decrease in T3, T4, fT3 and fT4 concentrations (P < 0.05). In opposite to HYPO rats, adipose adiponectin gene expression was increased in HYPER rats during the 6-week treatment in parallel with an increase the thyroid hormones concentrations (P < 0.05), and its expression was decreased 2 weeks after HYPER cessation (P < 0.05). Adiponectin gene expression levels showed significant negative correlations with concentrations of LDL (HYPO; r = -0.806, P = 0.001 and HYPER; r = -0.749, P = 0.002), triglyceride (HYPO; r = -0.825, P = 0.001 and HYPER; r = -0.824, P = 0.001) and significant positive correlations with concentrations of glucose (HYPO; r = 0.674, P = 0.004 and HYPER; r = 0.866, P = 0.001) and HDL (HYPO; r = 0.755, P = 0.001 and HYPER; r = 0.839, P = 0.001). The current study provides evidence that adiponectin gene expression in adipose tissue is regulated by thyroid hormones at the translation level and that lipid and carbohydrate disturbances in a patient with thyroid dysfunction may be, in part, due to adiponectin gene expression changes.