Background & Objectives: Regarding the admitted cases at early infancy in Tabriz Pediatrics Medical Center, this research was carried out to determine the role of Hep.B. vaccination in the incidence of ITP.

 Methods: We studied all patients’ admission files in Tabriz Pediatrics Center from 1993 to 2002. The patients were under 6 months of age and hospitalized with the impression of ITP. There were 25 infants whose ITP was diagnosed upon their clinical findings, blood counts and bone marrow aspiration and confirmed by exclusion of other causes of thrombocytopenia. Hep. B. vaccination has been included in routine immunization in Iran since 1993. In order to compare the incidence rate of ITP before and after 1993, we also sought all ITP patients’ files at the same age group who had been admitted to Tabriz Pediatrics Center during the decade before the beginning of routine Hep.B. vaccination (i.e. 1982 to 1992).

 Results: This study shows a considerable increase in incidence of ITP in infants under 6 months of age between 1993 asnd 2002 compared to the decade before the beginning of Hep.B.vaccination, which is statistically significant (P=0.0029).

 Conclusion: Although there is no facility to measure antibodies in Iran and many other countries, and this is one of the reasons for lack of proof for existence of a relationship between vaccination and ITP incidence, the study of cases in two different periods may strengthen the role of Hep.B. vaccination in the occurrence of ITP at early infancy.

  Background and objectives: Rubella is a mild viral infectious disease usually occurs sub-clinically without a serious complication, but if occur during pregnancy, specially the first trimester, its etiologic agent can transmit and invade to fetus causing congenital rubella syndrome (CRS) or fetal death. In order to prevent disease and its congenital complications, Rubella immunization is currently done in many countries. Nearly 20 % of girls at marriage were susceptible to rubella in 2003. That is why early all Iranians at the age of 5-25 years old were vaccinated against rubella and the vaccine was included in the compulsary immunization, MMR afterwards.

  Methods: This cross-sectional and analitical study was carried out on 140 girls who attended at a marriage consultancy center in Kermanshah city. Annually, about 10000 girls attend Rafattieh Health Center for pre-marriage laboratory tests in Kermanshah. It was expected that rate of sero-positive Rubella increase from 80 % in 1999 to above 90 % at the study time after mass and national vaccination. So considering 95 % of confidence. All Samples were tested using ELISA serologic method.

  Results: Antibody positivity and immunity against rubella was seen in 99.3 % (139 out of 140 vaccinated girls), while it was 80 % according to the similar study conducted on 240 unvaccinated girls at the same place in 1999. Comparing these two studies showed that attack rate (sero-negativity) has been decreased from 17.08 % in unvaccinated to 0.71 % in vaccinated ones with a confidence interval of 0.01- 0.30 (p < 0.01). The vaccine efficacy is estimated 96 %.

  Conclusion: Relationship between immunity, age, education and history of rubella-like illness, could not be assessed because only 1 (< 0.1%) of 140 vaccinated girls was not immune. In our previous studey in 1999 we had recommended to screen for susceptibility to rubella before marriage, which is no longer required since more than 99 % of vaccinated girls showed immuninty at the time of marriage. However, as sustainability of immunity after rubella vaccination is usually less than immunity due to illness, we recommend screening for rubella protective antibody every few years.

  Adjuvants are chemicals, microbial components, or mammalian proteins that enhance the immune response to vaccine antigens. Reducing vaccine-related adverse effects and inducing specific types of immunity has led to the development of numerous new adjuvants. Adjuvants in experimental and commercial vaccines include aluminum salts (alum), oil emulsions, saponins, immune-stimulating complexes (ISCOMs), liposomes, microparticles, nonionic block copolymers, derivatized polysaccharides, cytokines, and a wide variety of bacterial derivatives. The mechanisms of action of these diverse compounds are different. Factors influencing the selection of an adjuvant include animal species, specific pathogen, vaccine antigen, route of immunization, and type of immunity needed. In this paper we review the current adjuvant types, structure and mechanism of action and their application in the design and production of animal and human vaccines to provide a source for students and researchers in related fields .

  Background & objectives: Yersiniosis is created by Yersinia enterocolitica O:8 and causes problems in the world especialy in cold and mild countries. The purpose of this study is to evaluate the immunogenicity of Yersinia enterocolitica O:8 oligopolysaccaride (OPS) conjugate to diphtheria toxoid (DT) as a vaccine candidate.

  Methods : After cultivation of bacteria, the LPS were isolated by modified hot phenol method. Then dialysis and concentration were done and the OPS were extracted by acetic acid 2%. To conjugate with diphtheria toxoid, ADH was used as a spacer molecule and EDAC as a linker. Conjugate was purified by gel filtration. Then 4 groups of female BALB/c mice were selected (15 mice in each group). Injection was performed intraperitoneally in three doses with two weeks interval. Then serum samples were collected and antibody response against OPS was measured by indirect ELISA method for detection of total IgG, IgA, IgM, IgG1, IgG2a, IgG2b and IgG3.

  Results: After second and third doses, OPS-DT recieved group showed significant increase in all types of antibodies titer in anti-OPS in comparison to group that recived nonconjugated OPS. The increase in titer of antibodies was as: OPS-DT>OPS>DT. A remarkable increase was shown in total IgG and IgM titers (with total amount of 3204 and 670, respectively). In IgG1 subclass the amount was 920 and in other subclasses of IgG (IgG3, IgG2a and IgG2b) the amounts were 910, 110, and 99, respectively.

  Conclusion: The results shows that OPS of Yersinia enterocolitica O:8 increases the anti-OPS antibodies in the form of conjugate with diphtheria toxoid and could be considered as an appropriate vaccine candidate.