Immunogenicity of glycine nanoparticles containing a chimeric antigen as Brucella vaccine candidate

Purpose@#Brucellosis as a worldwide zoonotic illness affect domestic animals and humans doesn’t have any vaccine for the prevention of infection in humans yet. The aim of this study was to evaluate the specific immune response following the administration of glycine nanoparticles as adjuvant and delivery system of a chimeric antigen contained trigger factor, Omp31, and Bp26 in murine model. @*Materials and Methods@#The chimeric antigen of Brucella was cloned and expressed in Escherichia coli (E. coli) BL21 (DE3). Purification and characterization of recombinant protein was conducted through Ni-NTA (nickel-nitrilotriacetic acid) agarose, SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), and Western blot. Nanoparticle characteristics including morphology, particle size distribution, zeta potential, protein retention rate, and release rate were measured in vitro. Subsequently, nanoparticle contained antigen was administered to mice and blood sample was taken to measured the antibody level. @*Results@#The protein retention in the nanoparticles was successfully done and the nanoparticle characteristics were appropriate. The average size of glycine particles containing antigen was about 174 nm, and the absorption of protein was approximately 61.27% of the initial value, with a release rate of approximately 70% after 8 hours. Enzyme-linked immunosorbent assay result proved that the immunized sera of mice which were administered with nano-formula contains high levels of antibodies (immunoglobulin G) against recombinant chimeric antigen and also a high level of mucosal antibody (immunoglobulin A) in the oral group, which showed a desirable immunity against Brucella. @*Conclusion@#The results showed that chimeric antigen-loaded glycine nanoparticles can act as a vaccine candidate for inducing the cellular and humoral immune response against brucellosis.

Curcumin-loaded chitosan tripolyphosphate nanoparticles as a safe, natural and effective antibiotic inhibits the infection of Staphylococcus aureus and Pseudomonas aeruginosa in vivo

Curcumin as a yellow natural compound extracted from turmeric root is known it as an antibacterial agent. One of the nanoparticles ability is to decrease the defects of usual drug delivery systems. Chitosan is a low toxic, biodegradable, biocompatible and safe polymer which is used in production of nanoparticles. Nanoparticles like chitosan-tripolyphosphate [TPP] are able to increase antibacterial properties of curcumin. Curcumin-loaded chitosan-TPP nanoparticles containing chitosan, curcumin and TPP salt were synthesized by ionotropic gelation methods. First, the skin of anesthetized mice was inoculated with staphylococcus aureus and pseudomonas aeruginosa suspension. Then the infected mice were treated with curcumin-loaded chitosan-TPP nanoparticles for 3 days. Following that, antibacterial characteristics of the mice treated with curcumin-loaded chitosan- TPP nanoparticles were evaluated by bacterial culture of these mice. Our results showed the size of 160 +/- 10 nm and the charge of +7 +/- 2 mV in curcumin-loaded chitosan-TPP nanoparticles. These nanoparticles were also spiral shape. The encapsulation efficiency of curcumin in chitosan-TPP nanoparticles was 75 +/- 2%. Bacterial culture showed that curcumin-loaded chitosan-TPP nanoparticles inhibited staphylococcus aureus and pseudomonas aeruginosa growth. Our study demonstrated that curcumin-loaded chitosan-TPP nanoparticles can be utilized as a potent agent in treatment of Staphylococcus aureus and Pseudomonas aeruginosa infections

Ganoderma lucidum induces the expression of CD40/CD86 on peripheral blood monocytes

The major immuno-modulating effects of Ganoderma lucidum include mitogenicity and activation of immune effector cells such as T cells, macrophages and natural killer cells resulting in the production of cytokines. The purpose of this study was to evaluate the expression of CD40 and CD80 by G. lucidum-treated human peripheral blood mononuclear cells. Monocytes were isolated and incubated at 37°C and 5% CO[2] for 24 h and 48 h in the presence or absence of different concentrations of G. lucidum. Cells were then incubated with labelled monoclonal antibodies against CD14, CD40 and B7-1[CD80] molecules utilizing standard protocols, and analyzed by flow cytometry. The results showed that incubation of monocytes with G. lucidum led to marked enhancement of CD40 and B7-1 expression in a doseand time- dependent manner [p < 0.001]. G. lucidum was more effective in enhancing the expression of CD80 and CD40 molecules of cells obtained from females than male donors [p < 0.001]. G. lucidum enhanced the expression of CD40 and CD80 molecules on peripheral blood monocytic cells derived from both sexes in a dosedependent manner, with a preferential higher effect on cells obtained from female donors

Effects of T-2 toxin on cytokine production by mice peritoneal macrophages and lymph node T-cells

T-2 toxin is a mycotoxin of type A trichothecenes produced by several fungal genera such as Fusarium species. Mycotoxins can affect both cell mediated and humoral immune compartments. The purpose of this study was to investigate the effect of T-2 toxin on cytokine production by mouse peritoneal macrophages and lymph node T cells. Mouse peritoneal macrophages and lymph node T cells were isolated and treated with different concentrations of T-2 toxin and incubated at 37°C and 5% CO2 in air for 48 hours. Cell free media were removed and used for cytokine assay by an ELISA method. T-2 toxin significantly reduced IL-1beta release in a concentration dependent manner [p < 0.005, p < 0.001]. Interleukin-12 and TNF-alpha production were significantly increased in response to 0.001ng/ml, 0.01ng/ml and 0.1ng/ml of T-2 toxin [p < 0.001]. However, T-2 toxin at higher concentrations ranging from 1ng/ml to 100ng/ml, reduced both IL-12 [p < 0.001] and TNF-beta production [p < 0.005, p < 0.05]. The effects of T-2 toxin on lymph node T cells showed that IL-4 and IL-10 release was decreased in a concentration dependent manner [all with p < 0.01]. T-2 toxin at concentrations between 1ng/ml and 100ng/ml reduced the release of both IL-2 and IFN-gamma [p < 0.05, p < 0.001]. The results suggest that T-2 toxin at low concentrations can highly induce secretion of IL-12, TNF-alpha, IFN-gamma and IL-2 and it may be used as a positive immunomodulator in the human model

Evaluation of primary failure of new measles vaccine and secondary failure of previous measles vaccine after mass vaccination in military cadets in Iran

Measles is an acute highly infectious respiratory viral disease. It remains a leading cause of death among young children especially in developing country. Measles outbreaks occurred in Iran in recent years and soldiers and cadets have been vaccinated against it. This study was designed to evaluate primary and secondary failure of measles vaccine in cadets after mass measles vaccination. For this cross-sectional study, one month after mass vaccination in 2003, all vaccinated cadets were recruited. Eight hundred and sixty five cadets were evaluated in a simple random fashion. From each individual 5ml blood sample was obtained and checked in immunology laboratory of Baqiyatallah hospital. Antibody was checked by enzyme-linked immunosorbent assay [ELISA] for qualitative and quantitative measurement of IgG and IgM in accordance with Behring ELISA kit [Germany] instructions. Cut-off OD upper than 0.2 was considered positive and quantitative titer upper than 345 mIU/ml was considered protective. All cadets were men with a mean age of 19.0 +/- 1.1 years. IgM anti-measles antibody was positive in 0.7%. Primary failure was positive in 1.8% of individuals. Anti measles IgG antibody was positive in 97.8% of cadets. History of childhood vaccination for measles was positive in 67.7% and past history of measles was positive in 23 cases [2.6%]. Our results showed that secondary failure is more than 97%. Therefore, periodic studies should be performed to assess secondary failure rate in order to take preventive measures in time, of course, if its outbreaks are probable to happen

Effect of ganoderma lucidum on cytokine release by peritoneal macrophages

The water-soluble extract of Ganoderma lucidum [Reishi] has been used as an immunomodulator to stimulate spleen cells proliferation and cytokine expression. To investigate the effect of Ganoderma lucidum [G. lucidum] on cytokine production by mice peritoneal macrophages. Mice peritoneal macrophages were prepared by intra-peritoneal injection of 5 ml cold PBS. Peritoneal macrophages were plated out at 1X106 cell/well in 1ml RPMI 1640 medium supplemented with 10%FCS, 50 microg streptomycin and 50U penicillin. Cells were incubated in the presence or absence of different concentrations of G. lucidum at 370C and 5% CO2 for 48 hours. Cell free medium was removed and used for cytokine assay by ELISA method [Bender med system]. The results showed no significant differences in cell viability at concentrations ranged from 0-40 microg/ml compared with control group. G. lucidum enhanced IL-1beta, TNF-alpha and NO production in a concentration dependent manner. However, it is not clear if the enhancement of NO release is due to direct effect of G. lucidum on NO synthesis or by indirect endogenous modulation via cytokines. IL-12 release by peritoneal macrophages was also increased in response to different concentrations of G. lucidum, but maximum enhancement was induced in response to 5 microg/ml of G. lucidum [p<0.001]. Our results indicate that G. lucidum at concentrations used has a positive effect on cytokine release and NO production by peritoneal macrophages. Therefore, it is concluded that G. lucidum at moderate concentrations improves macrophage function through cytokine and NO release

Sero-Surveillance of Measles in Iranian Army Students after Nationwide Revaccination in 2004

Decay of vaccine-induced antibody titres without boosting of the wild measles virus has been well documented. Revaccination against measles has reduced the prevalence of the disease worldwide. Revaccination may cause IgE induced anaphylaxis. To study measles IgG antibody in revaccinated populations and its relation to IgE induced hypersensitivity. Blood samples were taken from 800 volunteer army students aging from 18-22 years after one month of nationwide revaccination in Tehran in the year 2004. Sera were collected and kept frozen until used. Anti-measles IgG antibody and total IgE antibody were measured by ELISA assay. Data indicated that only 2.37% of subjects were negative for measles antibody [titre less than 500] after a single dose of booster vaccination. From those individuals with positive IgG, 200 cases [25%] had antibody titres over 5000 IU/ml. The results showed a maximum IgE antibody titre of 1000 IU/ml [p<0.02] in which thirty cases [3.75%] had IgE titres over 1000 IU/ml [p<0.02]. Single vaccination against measles during childhood is not sufficient for protecting against measles virus and revaccination is needed to recall specific immunity, although like other viral infections it may trigger IgE antibody responses in a small percentage of the population