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Introduction: In this study, an in situgel-forming chitosan hydrogel was prepared with the use of glutamate salt of chitosan (Ch-Ga), β-glycerophosphate (Gp), and morphine (Mor). The paper is focused on in vitrophysicochemical properties and in-vivoanalgesic effects of the prepared chitosan hydrogel.Method: The thermosensitive properties of prepared chitosan hydrogel were evaluated during the different temperatures and times. The physicochemical properties of chitosan hydrogel were investigated by infrared (IR) spectroscopy and X-ray diffraction analysis (XRD). Also, its cell cytotoxicity effects were evaluated in murine NIH/3T3 normal cells. Subsequently, the distribution of chitosan hydrogel in the nasal cavity of rats and its analgesic responses were evaluated. The prepared chitosan hydrogel showed that it could be gelled at the temperature of 34 °C before leaving the nose in the shortest possible time of 30 s.Result: The analgesic responses of the intranasal (IN) injection of chitosan hydrogel (IN-chitosan hydrogel, 10 mg Mor/kg) in a single unit dose in rat relative to the placebo and intranasal or intraperitoneal (IP) injection of free morphine solution (IN-Free Mor or IP-Free Mor, 10 mg Mor/kg) via the hot plate test, reveal that the IN-chitosan hydrogel could induce fast analgesic effects of morphine with maximum possible effect (MPE) of 93% after 5 min compare to the IN-Free Mor and IP-Free Mor with MPE of 80% after 15 min and 66% after 30 min, respectively. Also, prolonged analgesic effects with MPE of 78 % after 6 h of injection were only seen in the IN-chitosan hydrogel injected group. The obtained fluorescent images of rat’s brain injected with IN-chitosan hydrogel containing doxorubicine (Dox) as a fluorescent agent showed that the mucosal adhesive and absorption enhancer properties of IN-chitosan hydrogel resulting in longer presence of them in the nasal cavity of rats followed by more absorption of Dox from the blood vessels of olfactory bulbs with a 74% color intensity compared to the IN-Free Mor and IN-Free Dox with 15%.Conclusion: These data reveal that the IN-chitosan hydrogel could induce fast and prolonged analgesic effects of morphine compare to the IN/IP-Free Mor, which could be considered as an in situgel-forming thermosensitive chitosan hydrogel for nasal delivery of wide ranges of therapeutic agents.

Autoimmune diseases are considered as one of the most important disorders of the immune system, in which the prolonged and chronic processes eliminate self-tolerance to the auto-antigens. The prevalence of autoimmune diseases has been increasing worldwide in the recent years. According to the literature, biological processes such as the host genome, epigenetic events, environmental condition, drug consumption, and infectious agents are the most important risk factors that make the host susceptible to the development of autoimmune diseases. In the recent years, the role of Helicobacter pyloriin the induction of autoimmune diseases has attracted extensive attention. Via molecular mimicry, epitope spreading, bystander activation, polyclonal activation, dysregulation in immune response, and highly immune-dominant virulence, such as cagA, H. pyloricauses tissue damage, polarity, and proliferation of the host cells leading to the modulation of host immune responses. Moreover, given the large population worldwide infected with H. pylori, it seems likely that the bacterium may develop into autoimmune diseases through dysregulation of the immune response. The frequency and relationship between H. pyloriinfection and systemic lupus erythematosus, rheumatoid arthritis, autoimmune atrophy gastritis, and autoimmune pancreatitis were evaluated using the data from 43 studies involving 5052 patients. According to statistical analysis it is probable that infection with more virulent strains of H. pylori(such as H. pylori cagApositive) can increase the risk of autoimmune diseases. In addition, it was shown that infection with H. pylorican prevent the development of atrophic gastritis by stimulating inflammation in the gastric antrum. However, future studies should confirm the validity of this study.

Background: The engineered chimeric peptides including functional multi-epitope structures fused by various peptide linkers are widely applied in biotechnological research to improve the expression level and biological activity of chimera. Objective: The aim of our study was to evaluate the effect of helical and flexible linkers on solubility, expression level and folding of multi-epitope chimera containing four epitopes of Human T Lymphotropic Virus Type 1 (HTLV-1). Methods: For this purpose, the chimera sequences connected by the helical or flexible linker were inserted into different plasmid vectors and expressed in E. coli strains. The expressed products were analyzed using SDS-PAGE and Western blot techniques. Additionally, the molecular modeling study of the chimera with helical or flexible linker was performed using iterative threading assembly refinement (I-TASSER) to attain their three-dimensional structures. Results: Comparison of the chimera expression indicated that the insertion of a flexible (GGGGS)3 linker among chimera epitopes could significantly enhance the level of expression, whereas, the low-level of chimera expression was observed for chimera containing the contiguous helical (EAAAK)5 linker. According to the results of sequence alignment and plasmid stability test, the structure and function of a consecutive helical linker among chimera epitopes were similar to porins as the outer-membrane pore-forming proteins. The molecular modeling results confirmed our experimental study. Conclusion: This investigation illustrated the key role of linker design in determining the expression level of multi-epitope chimera and conformational folding.

Objective: An injectable long acting In-Situ Forming Gel (ISFG) of human Growth Hormone (hGH) was prepared by using triblock PCL-PEG-­PCL (Mw 1500-1500-1500). Ring-Opening Polymerization (ROP) of triblock using microwave was applied. Methods: The BCA protein assay Kit was used to determine the concentration of hGH in the in-vitro release medium. Finally, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) tests and Circular Dichroism (CD) spectrum were done to approve the stability of released hGH. The result of ROP demonstrated that the proportion of PCL to PEG accorded with the initial molar ratio of the monomers. The cross-section of the Surface Electron Microscopy (SEM) indicated the porous framework of the hydrogel could load the drug into its tridimensional matrixes structure. There is the low initial burst release of hGH from the supramolecular hydrogel. Results: The maximum in-vitro release of hGH was 71.2 % ± 1.5 that were due to hGH degrading after this time (21 days). The CD spectrum and SDS-PAGE results confirmed the stability of hGH during invitro release evaluation. Conclusion: The results suggest that the sustained-release formulation using PCL-PEG-PCL can be applied to control the release of hGH.

Objective: An injectable long acting In-Situ Forming Gel (ISFG) of human Growth Hormone (hGH) was prepared by using triblock PCL-PEG-PCL (Mw 1500-1500-1500). Ring-Opening Polymerization (ROP) of triblock using microwave was applied. Methods: The BCA protein assay Kit was used to determine the concentration of hGH in the in-vitro release medium. Finally, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) tests and Circular Dichroism (CD) spectrum were done to approve the stability of released hGH. The result of ROP demonstrated that the proportion of PCL to PEG accorded with the initial molar ratio of the monomers. The cross-section of the Surface Electron Microscopy (SEM) indicated the porous framework of the hydrogel could load the drug into its tridimensional matrixes structure. There is the low initial burst release of hGH from the supramolecular hydrogel. Results: The maximum in-vitro release of hGH was 71.2 % ± 1.5 that were due to hGH degrading after this time (21 days). The CD spectrum and SDS-PAGE results confirmed the stability of hGH during invitro release evaluation. Conclusion: The results suggest that the sustained-release formulation using PCL-PEG-PCL can be applied to control the release of hGH.

Tuberculosis (TB) is a re-emerging disease and is caused by Mycobacterium tuberculosis(M. tuberculosis). TB is currently one of the leading causes of morbidity and mortality, worldwide. The only available vaccine against TB infection, Bacillus Calmette–Guérin (BCG), fails to adequately protect against reactivation of latent infections in adults. Furthermore, recently developed subunit vaccines, which are in various stages of clinical trials, are all prophylactic vaccines based on proteins expressed in replicating stage of M. tuberculosisand they are not preventive of reactivation of latent TB infection. Thus, an appropriate subunit post-exposure vaccine needs to be developed to control all forms of TB infection. To produce a multi-stage subunit vaccine, scientists should combine the early secreted M. tuberculosisantigens with latency antigens. For this purpose, some latency proteins are known which could be important antigens in the production of specific humoral and cellular immune responses in latent M. tuberculosisinfected individuals. Several studies have evaluated the immunogenicity of these proteins in improving the TB vaccines. The present study is a comprehensive review of several studies on the role of the latency antigens in the development of TB vaccines. Overall, the studies indicate that the latency-associated antigens including the resuscitation-promoting factors, the Dormancy of survival regulon (DosR) proteins and the starvation stimulant proteins are potential candidates for the development of subunit vaccines against TB infection.

This study was conducted regarding the potentials of the carrier-mediated pulmonary delivery in treatment of the Tuberculosis (TB).

For efficient mucosal vaccine delivery, nanoparticulate antigens are better taken by microfold cells in the nasal associated lymphoid tissue and also dendritic cells. Nanoparticles based on polymers such as chitosan (CHT) and its water soluble derivative, trimethylchitosan (TMC), could be successfully used as carrier/adjuvant for this purpose. Sodium alginate, a negatively charged biopolymer, could modify the immunostimulatory properties of CHT and TMC NPs and increase their stability. Sodium alginate (ALG)-coated chitosan (CHT) and trimethylchitosan (TMC) nanoparticles (NPs) loaded with inactivated PR8 influenza virus were successfully prepared by direct coating of the virus with CHT or TMC polymers to evaluate their immunoadjuvant potential after nasal immunization. After nasal immunizations in BALB/c mice, PR8-CHT formulation elicited higher IgG2a and IgG1 antibody titers compared with PR8-TMC. ALG coating of this formulation (PR8-CHT-ALG) significantly decreased the antibody titers and a less immune response was induced than PR8-TMC-ALG formulation. PR8-TMC-ALG formulation showed significantly higher IgG2a/IgG1 ratio, as criteria for Th1-type immune response, compared with PR8-CHT-ALG and PR8 virus alone. Altogether, the PR8-TMC-ALG formulation could be considered as an efficient intranasal antigen delivery system for nasal vaccines.

Tuberculosis (TB) is a contagious infectious disease caused by Mycobacterium tuberculosis(Mtb). This disease with two million deaths per year has the highest mortality rate among bacterial infections. The only available vaccine against TB is BCG vaccine. BCG is an effective vaccine against TB in childhood, however, due to some limitations, has not proper efficiency in adults. Also, BCG cannot produce an adequately protective response against reactivation of latent infections. In the present study we will review the most recent findings about contribution of HspX protein in the vaccines against tuberculosis. Therefore, many attempts have been made to improve BCG or to find its replacement. Most of the subunit vaccines for TB in various phases of clinical trials were constructed as prophylactic vaccines using Mtb proteins expressed in the replicating stage. These vaccines might prevent active TB but not reactivation of latent tuberculosis infection (LTBI). A literature search was performed on various online databases (PubMed, Scopus, and Google Scholar) regarding the roles of HspX protein in tuberculosis vaccines. Ideal subunit post-exposure vaccines should target all forms of TB infection, including active symptomatic and dormant (latent) asymptomatic forms. Among these subunit vaccines, HspX is the most important latent phase antigen of M. tuberculosis with a strong immunological response. There are many studies that have evaluated the immunogenicity of this protein to improve TB vaccine. According to the studies, HspX protein is a good candidate for development of subunit vaccines against TB infection.

The use of electrospinning fibers in rapid-dissolving drug delivery systems accelerates the release of the active substance due to their extensive contact surface and porosity. Sumatriptan succinate (SS), an antimigraine drug has beneficial and proven effects on human health, but it has some shortcomings such as bitter-taste, low oral absorption and low half-life that limit its application in pharmaceutical systems. In this work, the new nanofiber mats were developed to increase oral absorption and improve the efficacy of drug. The mean fiber diameters were 313.29 ± 31 nm, 373.37 ± 29 nm and 453 ± 42 nm for those loaded by 0.15% SS, 0.5% SS and 1% SS, respectively. By adding sumatriptan succinate to the electrospinning solution, viscosity, electrical conductivity and tensile strength in fibers increased, but pH decreased. Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC) and X-Ray diffraction (XRD) analyses confirmed the absence of interactions between drug and polymer membrane. A fast release rate was obtained for sumatriptan-loaded soluble soy bean polysaccharide (SSPS) nanofiber mats, where 95% of the sumatriptan released within 20 s. Cytotoxicity evaluation revealed that none of the nanofibers had toxic properties on the fibroblasts cells. Overall, sumatriptan can be loaded well in SSPS nanofibers and released more quickly in oral space, which will be effective in improving the onset of therapeutic effects and reducing migraine headaches.

Aerosolized chemotherapeutics leads to higher, localized and continuous concentrations of active agents in lung tissue with lower side effects for other organs. The present study was performed on jugular vein cannulated rats which endothracheally received 4 mg/kg of free paclitaxel powder (Free-PTX), paclitaxel-loaded alginate microparticles (PTX-ALG-MPs) and i.v. paclitaxel (Anzatax®). Pharmacokinetic parameters for Free-PTX and PTX-ALG-MPs contain higher AUC, mean residence time (MRT),half-life and bioavailability, with lower elimination constant (ke). Statistical analysis showed that the amount of paclitaxel per gram of lung tissue after 0.5, 6 and 24 h after administration of Free-PTX was lower than PTX-ALG-MPs. Lung tissue AUC for Free-PTX was lower than PTX-ALG-MPs. According to the obvious advantages obtained, such as dose lowering and increasing paclitaxel residence time and half-life. It should be noted that cell cytotoxicity test on normal airway cell lines was not examined in this study but due to previous reports on safety of inhaled paclitaxel, it can be suggested that pulmonary delivery of paclitaxel can be a useful non-invasive route of administration compared with i.v administration.

Delivery to the lungs is an efficient way to deliver drugs directly to the site of action or to the blood circulation. Because of limitations of direct administration of free drugs, particulate drug delivery systems such as DPI formulations based on nanoparticles (NPs) have been of interest for pulmonary drug delivery. The prolonged residence of NPs in the lungs due to ability to escape from the clearance mechanisms such as mucociliary escalator, macrophage uptake (a size of 1–2 μm is ideal for macrophage phagocytosis), and translocation to the systemic circulation is amongst the key advantages of NPs. By this approach, the controlled pulmonary delivery of drugs, peptides, proteins, genes, siRNA, and vaccines is possible. Both natural (albumin, gelatin, alginate, collagen, cyclodextrin, and chitosan) and synthetic (poly (lactide-co-glycolide) (PLGA), polyacrylates and polyanhydrides) polymers have been used in formulation of pulmonary nanovectors. As direct pulmonary administration of NPs is not feasible, by using the safe excipients, NPs could be converted to dry powder inhaler (DPI) formulations. These can provide a promising deposition and stability of NPs. In this article, the DPI formulations based on polymeric nanoparticles have been reviewed and categorized based on the polymer type used for preparation of NPs.

Therapeutic protein and peptides have gained dramatic interest in the recent years for the chronic diseases, although there are specific limitations in the delivery route. Due to degradability and low absorption, they are usually administered through parenteral route. However, due to low patient compliance and side effects studies have moved towards less invasive drug delivery systems. Pulmonary drug administration is among the promising alternatives since studies proved acceptable bioavailability and stability of the such protein-based medicines. Moreover, there are different pulmonary administered drugs such as Pulmozyme®, Exubera® and Afrezza® which are FDA approved. The critical issue is the stabilization of proteins through developing desirable dry powder formulations. So that different drying techniques and stabilizing excipients are evaluated. Various drying methods such as spray drying, freeze drying and supercritical fluid are used to achieve inhaled protein and peptide powders with desirable properties. The current paper discusses the main drying methods for inhalation delivery of proteins and peptides. Additionally, it categorizes existing inhaled peptides and proteins according to preparation techniques and formulations. Recent advances in drying methods such as supercritical fluid assisted atomization introduced by hydrodynamic cavitation mixer (SAA-HCM) technique is further discussed.

Chitosan solution containing glycerolphosphate disodium salt (Gp) is an injectable thermosensitive in situ gel-forming system which undergoes sol–gel transition under certain physiological pH and temperature conditions. When a drug-incorporated chitosan/Gp solution is injected into the body, it forms a three-dimensional gel at 37 °C, which allows the drug to be released in a sustained manner. This hydrogel can be used as a drug delivery system for prolonged release of peptides and glycopeptides. The objective of this work was to investigate the effect of different excipients on the sol–gel behavior of this thermosensitive hydrogel. Chitosan polymeric solutions (2 % w/v) containing Gp and different excipients, such as hydroxypropyl methyl cellulose (HPMC), polyethylene glycol (PEG) with two different molecular weights (PEG200 and PEG1000), and poloxamer (F127) in various concentrations, were prepared, and the pH, sol–gel transition time, and syringeability of the final solutions were evaluated. The obtained results point to HPMC as the best additive for chitosan/Gp solutions in developing an in situ gel-forming drug delivery system with optimum gelling time. A significant decrease was noted in the sol-to-gel transition time (from 90 to 60 s) when HPMC was added to the system. This may have been due to the HPMC structure which acted as a viscosity-enhancing and gel-promoting agent. The in vitro release of vancomycin hydrochloride from chitosan/Gp/HPMC hydrogel was also studied. Vancomycin release studies showed a sustained release profile for over 20 days. It can be concluded that combining chitosan/Gp and HPMC is a promising strategy for preparing a thermally reversible in situ gel-forming delivery system with an optimized gelation time.

Orally administered Insulin have to survive the harsh gastrointestinal tract condition, penetrate the enteric epithelia barrier and bypass first pass effect before reaching the bloodstream. To address this problem, PEGylated liposomal insulin was prepared and modified with B12 to improve stability and absorption of insulin in gastro intestinal environment. Liposomes were prepared by film method plus extrusion, linked to B12and characterized for their particle size, zeta potential, encapsulation efficiency (EE%). The release profile in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was evaluated.