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Background & Objective: Approximately one-third of the world’s population is infected with Mycobacterium Tuberculosis (TB), which is a indicator of high distribution of these bacteria in our environment. The only vaccine currently available against TB is the attenuated Mycobacterium Bovis strain bacillus Calmette-Guerin (BCG), which used regularly for many years to prevent the Tuberculosis in Iran and many part of the world. The efficiency of this vaccine varies in different populations, and is a matter for discussion. On this basis, the present study has been set up to determine the level of Tuberculin reaction in 4.5 months and in 7 years old children that receive BCG vaccine at birth time, in Golestan province. Materials & Methods: 2700, 4.5 month infant and 2400, 7 years old children in Golestan province were chosen by cluster sampling after the proper permission from the parents, public health centers and educational authorities were taken. The presence of the BCG scar were assessed, and 0.1 ml of 5 tu Tuberculin were injected subcutaneously. The induration was measured 48-72 h after Tuberculin injection. The results were determined as present and compare with T-test. Results: In these study 2559 infants and 2193 child were taken part in the final evaluation. The BCG scar were present in 97.9% of infants and 87.8% of 7 years children, this difference was meaningful. The average induration in 4.5 months babies were 2.29 mm, and in 7 years child was 0.66 mm, this difference was significant (P<0.05). More than 44.7% of babies and 82% of 7 years children didn’t show any reaction after PPD test, this difference was also significant (P<0.05). Conclusion: The level of positive Tuberculin reaction in infants of this province in spite of vaccination was very low, and this level was reduced after 7 years time, this indicate that BCG vaccination at birth did not have any major role in positive Tuberculin reaction. Our results also indicate that the presence of scar can be a good indicator for previous vaccination. In regard to the negative Tuberculin reaction in majority of babies, it is suggested to evaluate the efficacy of BCG vaccine in preventing the TB disease itself, by other method such as studying the TB incidence among children in long term or by determination of cytokines level after Tuberculin injection.

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Background&Objective: Both CD4+ type 1 helper (Th1) cells and CD8+ T cells play effective roles in protection against Mycobacterium tuberculosis infection. MPB51, a major mycobacterial secreted protein, induces humeral and cellular immune responses against mycobacterial infection. In addition, DNA vaccine encoding MPB51 can induce cellular immune responses and protective immunity upon challenge with M.tuberculosis. This study address to identify T-cell immunodominant epitopes on MPB51 in BALB/c mice. Materials&Methods: We cloned DNA encoding MPB51 molecule in pCI plasmid. After constructing MPB51 DNA-covered gold cartridge, BABL/c mice were immunized by using a gene gun system. Two weeks after the last immunization, the immune spleen cells were cultured in response to synthetic overlapping library peptides covering the mature MPB51 sequence or medium alone. Intracellular and cell culture supernatant gamma interferon (IFN-) production was analyzed by using flow cytometry and ELISA, respectively. Results: The findings of present study indicate that DNA vaccination can course strong mmune response only against the peptides contain 21-40 aminoacids. Further analysis with a computer – assisted algorithm permitted the identification of nine aminoacids of (P24-32) as immunodominant CD8+ T cell epitope. Conclusion: This study proved than the MHC class I-peptide (H2-Dd-P24-32) complex is recognized by (IFN-)–producing CD8+ T cells. We observed by using T-cell subset depletion that CD8+ T cells are the only P24-32-responded T-cells in BABL/c mice. The data obtained are useful for identifying cellular immune responses against TB and for designing a new vaccine against M.tuberculosis infection.

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Background & Objective: Rubella vaccine is prepared with live virus thus if it injects during abstinence period, it can cause fetal risks. The aim of study was to evaluate rubella IGM among infants of women who were vaccinated against rubella during 3 months pre-or post-conception (abstinence period). Materials & Methods: This cohort study was done on 253 mothers, including 116 mothers as cases and 137 mothers as controls. The case group inadvertently had received MR vaccine (RA27/3) during abstinence period. The control group selected randomly from similar delivery center that admitted for delivery. The background and confounding factors was matched between the control and case groups. In both groups after delivery, cord rubella IGM was measured by ELISA for serological diagnosis of infant infection. Data was analyzed by Chi-square and T-student tests. Results: The findings showed that the number of positive IGM infant was similar in both groups (One positive IGM in each group). In spite of no significant difference between the case and the control groups, the maximum theoretical risk in this study was 4.392% (RR=1.091 95% CI=0.271-4.392). Conclusion: Although no significant difference was found from the point of infants with an IgM+ serology in two groups, according to the risk ratio obtained in this study, we still recommend vaccination should be avoided during abstinence period.

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Background and Objective: An increased risk of invasive infections with encapsulated bacteria such as Streptococcus pneumoniae has been described among splenectomized patients. Pneumococcal vaccination has been recommended in these patients. In this study, the serum antibody response to pneumococcal polysaccharide antigens in splenectomized patients with idiopathic thrombocytopenic purpura (ITP) or trauma who immunized with Pneumovax 23 was evaluated. Materials and Methods: This case - control study was performed on two groups of patients including fifteen cases of trauma patients (11 male, 4 female) and twenty patients with ITP (10 male, 10 female) along with 40 healthy volunteers as controls who were immunized with Pneumovax 23 to prevent pneumococcal infections. All patients received the pneumococcal vaccine before splenectomy. The serum antibody response (IgG and IgG2) to pneumococcal antigens was determined by enzyme-linked immunosorbent assay (ELISA) technique prior to vaccination and 4 weeks post-vaccination. Analyzing of data was performed using student t-test and linear regression test. Results: The mean of post-vaccination IgG or IgG2 titer to the pneumococcal antigens in ITP patient group was significantly lower than those in controls or in trauma group (P<0.05). No significant differences in IgG or IgG2 antibody titer increase were found between trauma group and healthy control group. Response to immunization was poor in 9 of 20 ITP patients. Conclusion: This study indicated that 45 percent of patients suffered from ITP who have undergone splenectomy responded poorly to pneumococcal antigens.

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Background and Objective: Human immunodeficiency virus (HIV) belongs to the retroviridae family and is the agent of acquired immunodeficiency syndrome (AIDS). Treatment of HIV for the global health has made a special importance for the new antiviral drug discoveries in addition to HIV vaccine developments. Materials and Methods: In this experimental study single cycle replicable (SCR) HIV-1 virions with the capability of one cycle of replication were produced by the co-transfection of three plasmids of pmzNL4-3, psPAX2 and pMD2.G to the HEK cells and their replication capacity of the first generation SCR visions in HEK 293T, MT-2, and mouse spleen cells was examined by p24-capture ELISA, syncytium formation assay. The infectivity of the SCR-produced virions was also analysed on MT-2 cells. Results: Experiments showed the efficient production of SCR virions. Moreover, results indicated the replication potency of SCR virions on the investigated cells and the inactivity of the produced SCR HIV virions. Complete HIV antigens are expressed in their native forms by SCR virions, but this second viral particles lack the replication capacity. Conclusion: SCR HIV virions produced in this study are capable of one cycle of replication and will be inactivated thereafter.These features make SCR virions as a good candidate for HIV vaccine studies. Moreover, considering the one cycle replication, SCR virions do not need the severe biosafety concerns involved in retrovirus studies.

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Background and Objective: Infection with HBV is the most common chronic viral infection and mortality in children. Prevention of this infection with vaccination is vital. This study was done to compare the antibody level in post hepatitis B vaccination in children with 12-15 and 21-24 months age. Materials and Methods:This descriptive study was carreid out on 186 children with 12-15 (group I) and 21-24 (group II) months age who had not infected with hepatitis B infection in, Bandarabbas Iran during 2009. The parents were HbsAg negative, without immunodeficiency diseases and did not receive hepatitis vaccination, blood or blood products transfusion. Age, gender, birth weight, breast feeding duration and gestational age were recorded for each child. Hepatitis B antibody level was measured with ELISA method. Data were analyzed using SPSS-16 and student t-test. Results: Antibody level in group I (231 mIU/ml) was significantly higher than group II (142.9 mIU/ml) (P<0.05). There was not significant differences between males and females. Antibody level was not significantly corrolated with body weight, gestational age and breast feeding duration. Antibody level lower than 10 mIU/ml were observed in 4.34% of group I and 20.8% of group II. This differnce was significant (P<0.05). Conclusion: This study showed that the protective effect of vaccination reduced after six months of final dosage.

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Background and Objective: Hepatitis B vaccination has been conducted in neonates in the routine vaccination in Iran since 1993. This study was carried out to evaluate the serum hepatitis B antibody level in vaccinated children after 14 years in Kashan, Iran. Materials and Methods: This prospetive cohort study was conducted on 200 fourteen-year-old children which were selected via a simple random sampling method in Kashan, Iran drung 2008-09. This subjects were have been vaccined according to the govermental guildline at 0, 2 and 6 months old. Two ml blood specimens were obtained from children and serum hepatitis B surface antibody (anti-HBs) and hepatitis B core antibody (anti-HBc) were determined by ELISA method. Immunity was interpreted as anti-HBs≥10 IU/L. Data were analyzed using SPSS-13, Chi-Square and Fisher’s exat tests. Results: 92% girls and 95% boys, totally 187(93.5%) children had serum anti-HBs≥10 IU/L. Anti-HBc was positive in 3 (3%) girls and 5(5%) boys, totally 8(4%) which all of them had serum anti-HBS≤10 IU/L. No case of positive HBs Ag was detected. Immunity was detected in 11 of 18 (61.1%) children with birth weight<2.5 kg and in 176 of 182 (96.7%) children with birth weight≥2.5 kg (P<0.05). Conclusion: The immunity following the complete series (0, 2, 6 months old) of hepatitis B vaccination remained detectable after 14 years.

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Background and Objective: Continuous antigenic variation of Influenza a viruses causes a major concern to develop Influenza vaccine. Conserved antigens are suitable candidates for vaccine production due to its non-requirement to match the designed strains with circulating strains. The M2 gene is conserved among Influenza a viruses and has potential to be considered as a universal vaccine. This study was designed to evaluate the effects of aqueous Echinacea purpurea extract on immunogenicity of DNA vaccine encoding M2 gene of Influenza virus. Materials and Methods: This interventional study was carried out on female BALB/c mice with 3-4 week age (250-300 gr). Plasmid DNA encoding M2 gene (pcDNA-M2) of Influenza virus A/New Caledonia/20/99 (H1N1) was transformed into E.coli top10 f' and cultured in LB broth media. Large scale plasmid preparation was done and the concentration was measured by spectrophotometric method. Mice were divided into eight groups and immunized three times with fifteen days apart. Vaccine groups received inactivated Influenza virus or pcDNA-M2, alone or in combination with Echinacea extract. Control groups were injected pcDNA, Echinacea extract, and phosphate buffer. All animals were left to bleed before immunization and at 21 days after the last vaccination and specific anti-M2 antibodies were measured by indirect ELISA. Then the mice were intranasally challenged under an aesthesia with mouse-adapted PR8 Influenza virus and monitored for 3 weeks to evaluate the vaccine regimen efficacy in reduction of mortality rate compared to control groups. Data were analyzed using SPSS-16, One-way ANOVA and Kaplan–Meier tests. Results: The highest specific immune response was obtained in mice received inactivated virus plus extract (P<0.05). Immune responses in mice inoculated with pcDNA-M2 were significantly higher compared to all control groups mice (P<0.05). In addition the specific immune responses in group inoculated with pcDNA-M2 and aqueous extract was higher compared to the group receiving only pcDNA-M2 (P<0.001). The highest survival rate was observed in mice injected with inactivated virus or pcDNA-M2 plus extract. Conclusion: This study showed that pcDNA-M2 induced specific immunity and protected mice against lethal challenge with PR8 Influenza virus. Furthermore, application of Echinacea extract with M2 gene vaccine increased vaccine efficacy.

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Background and Objective: Helicobacter pylori infection is one of the most common chronic bacterial infections all over the world, particularly in the developing countries. LeoA gene plays an important role in pathogenesis, and the main role of this gene is to increase the bacterial toxin secretion. This study was conducted to isolate and clone the leoA gene in a pEGFP-C2 expression vector and evaluate its expression in eukaryotic system.
Methods: In this laboratory study, the leoA gene was amplified from the standard strain of Helicobacter pylori genome (ATCC 43504) by PCR method. It was then inserted into the pTZ vector by cloning T/A. Sub cloning of this gene was performed in a pEGFP-C2 expression vector with a ligase enzyme. The final structure of pEGFP-C2-leoA was transformed by electroporation in CHO (Chinese hamster ovary) cells and the expression of the leoA gene was evaluated by SDS-PAGE and RT-PCR.
Results: The results of PCR indicated that the 1758 bp fragment was amplified from the leoA gene. Cloning of this gene was performed successfully in pTZ and pEGFP-C2 vectors, respectively. The enzyme digestion with two KpnI and SacII enzymes, as well as sequencing, confirmed the accuracy of gene cloning. The observation of the protein product of the leoA gene in CHO cells indicated the successful expression of the LeoA gene in the eukaryotic system of Helicobacter pylori.
Conclusion: The final construct of pEGFP-C2-leoA had a successful expression of the leoA gene in animal cells.

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Adjuvants are an essential component of modern vaccines. An adjuvant is an entity added to a vaccine formulation to ensure that robust immunity to the antigen is inoculcated. The adjuvant is typically vital for the efficacy of vaccines using subunit (pepdids, proteins and virus like particles) and DNA antigens. Furthermore, these components are used to reach the current new goals of preventing and/ or treating chronic infectious diseases and cancers. This review focuses on formulation aspects of adjuvants, safety considerations, progress in understanding their mechanisms of action and also their side effects with using 97 articles are acceceble in pubmed central and google scholar indexing which published during 1980-2016. Adjuvants can be broadly divided into two classes, based on their principal mechanisms of action; the first class are vaccine delivery systems that generally particulate and mainly function to target associated antigens into antigen presenting cells. The others are immunostimulatory adjuvants that predominantly derived from pathogens and often represent pathogen associated molecular patterns which activate cells of the innate immune system. Adjuvants induce cellular and humoral responses, in particular neutralizing antibodies that able to inhibit the binding of pathogens to their cellular receptors. Efficient Th1-immunity-inducing adjuvants are highly in demand. The adjuvants promote good cell-mediated immunity against subunit vaccines that have low immunogenicity themselves. However, attempts to develop a new generation of adjuvants, which are essential for new vaccines, is important, but their use is limited because, little is known about their mechanisms of action and health risks.

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Background and Objective: COVID-19 is a rapidly spreading acute respiratory syndrome worldwide. COVID-19 vaccination has been widely used as a means to control the disease. This study aimed to investigate the relationship between demographic characteristics and COVID-19 vaccination in patients with COVID-19.
Methods: This descriptive-analytical study was conducted on 1124 patients with a definitive diagnosis of COVID-19 in Minoodasht, Iran, in August 2021. The instruments used in this study included a demographic data questionnaire and a checklist assessing patient characteristics.
Results: The majority of COVID-19 patients were men (51.8%), aged between 35 to 45 years (26%), and married (76.5%). COVID-19 vaccination was administered to 26.6% of the patients. Patients who received vaccination (27.1%) used masks less than unvaccinated patients (72.9%) (P<0.05). Of the patients with COVID-19, 8.2% were hospitalized. The mean duration of hospitalization for vaccinated patients (7.8±6.4 days) was lower than that for unvaccinated patients (8.3±5.9 days); however, this difference was not significant. Age, education, underlying disease, and mask usage were associated with COVID-19 vaccination (P<0.05). With an increase in underlying disease and age, vaccination rates increased, while vaccination rates decreased with the use of masks and lower education.
Conclusion: Attention to demographic factors and certain characteristics of individuals is necessary to improve COVID-19 vaccination rates. Previous COVID-19 vaccination does not decrease the number of hospitalization days in patients with COVID-19.