Effects of Adjuvant and Immunization Route on Antibody Responses against Naja Naja oxiana Venom

Naja naja oxiana (NNO) is one of the important venomous species in Iran. The current snakebite treatment is antivenom therapy that deals with hyper immunization of horses with crude or fractionated snake venom plus traditional adjuvants, like Freund's adjuvant. For improvement of antivenom production, it has been suggested to use different adjuvant systems or immunization procedures. In this study, humoral immune responses against immunogenic fractions of NNO venom (NNO3 and NNO4) and crude venom have been compared by usage of different adjuvant and immunization routes. Additionally, a new indirect enzyme-linked immunosorbent assay (ELISA) was set up for the detection of specific antivenom antibodies. This study was conducted on six different groups of female Dutch rabbits that were hyperimmunized using crude and fractionated NNO venom, along with Freund's and MF59 adjuvants through subcutaneous or intramuscular route. The immunization was performed four times with 10-day intervals and the levels of specific antibodiees were detected by indirect ELISA. The statistical analysis reveals a negligible variation in the antivenom titers among the venom-inoculated groups, regardless of the adjuvant type or the immunization route. Finally, it was concluded that the fractions are efficient for antivenom production, and it is possible to use MF59 adjuvant via subcutaneous routes as an alternative to Freund's adjuvants considering its fair immunopotentiation capacity and safety in animals.

Propolis Silver Nanoparticles as an Adjuvant in Immunization of Rats with Citrobactor Freundii Antigens

This study aimed to examine the impact of Citrobacter freundii killed whole cell sonicated antigen (KWCSAg) alone and in combination with propolis nanoparticles on humoral immunoglobulin (IgG) and cellular immune responses of rats. The ELISA interleukin 4 (IL4) and IgG, delayed-type hypersensitivity (DTH) skin test, and phagocytosis activity tests were used in this study. In total, 45 rats were divided into five groups of 9 rats. The first group received a 1,000 μg\ml dose of KWCSAg-CF. The second group received an injection of 1,000 μg/ml of KWCSAg-CF antigen and 30 mg/ml of propolis AgNPs. The third group received an injection of 1,000 μg/ml of KWCSAg-CF antigen along with 10 mg/ml of propolis AgNPs. The fourth group was subjected to 30 mg/ml of propolis AgNPs. One ml of phosphate-buffered saline (pH 7.2) was injected into the fifth group (the negative control group). The rats received booster injections of the same antigens after 14 days. Blood was obtained from them to detect immunoglobulin and interleukin 4 (IL-4) on days 21, 28, 32, 46, 50, and 60 following the injection. The second group showed the most significant rise in IL-4 and IgG concentration, followed by the third group, the first group, and the fourth group, compared to the negative control group (fifth group). In all immunized groups, the DTH test results demonstrated an increase in the means of induration with significant differences (P<0.05) of the concentrated antigen after 24 and 48 h, and subsequently a decrease after 72 h, compared to the negative control group. At 48 h after the concentrated antigen was indurated, the second group displayed the most significant increase in diameter.

Evaluation of Cholera Toxin Adjuvanticity Effect on the Production of Specific Antibodies Induced by Avian Infectious Bronchitis Vaccine in Chickens

Cholera toxin (CT) is one of the most well-known immunostimulants. Mammalian studies have shown that CT can generate immune responses against antigen. However, it has not exhibited a definite effect on poultry yet. In this study, focusing on a cost-effective method, the effect of different concentrations of CT obtained from Vibrio cholerae biotype El Tor and serotype Inaba was investigated on the immunogenicity of infectious bronchitis vaccine. After culturing and concentrating CT, different concentrations of CT (0.1, 1, 2, and 5 micrograms) were combined with avian infectious bronchitis vaccine strain H120 produced by Razi Vaccine and Serum Research Institute (RVSRI) and, at 7 days of age, inoculated via the eye drop administration in 42 specific-pathogen-free chickens (seven groups of six chicks that included four experimental groups, two negative control groups (PBS and toxin), and one positive control group). Blood samples were taken weekly from the wing veins of the chickens, and the immunoglobulin G (IgG) titer was checked by enzyme-linked immunosorbent assay. The results showed that 2 µg of CT in comparison with other concentrations caused a significant increase in the antibody titer against avian infectious bronchitis in the blood serums of the chickens. One-way ANOVA test showed that all the results of this study were significant at P<0.05 level. Our data show that CT has the potential to further stimulate the immune system of chickens and may increase the immunogenicity of the infectious bronchitis vaccine. However, more research is needed to examine all aspects of the use of this toxin in animal vaccines.

Comparative Study on the Efficacy of MF 59, ISA70 VG, and Nano-Aluminum Hydroxide Adjuvants, Alone and with Nano-Selenium on Humoral Immunity Induced by a Bivalent Newcastle+Avian Influenza Vaccine in Chickens

Newcastle disease (ND) and Avian influenza (AI) are the major problems and the most economically important viral diseases in the poultry industry; therefore, vaccination against these diseases is considered one of the most effective ways of prevention. Extensive studies have been conducted to improve the performance of vaccines, and one of the major achievements of these studies is the preparation of adjuvants as stimulants of the immune system and one of the most important compounds in killed vaccines. An immunogenicity comparison of three adjuvants including, ISA70VG, Nano-Aluminum Hydroxide (Nano-Alum), and MF59 alone or with Nano-Selenium (Nano-Se), was performed using bivalent Newcastle plus Avian Influenza (ND+AI) killed vaccine. In this study, 105 specific-pathogen-free chicks (Ross-308) were divided into 7 treatments, including T1 (control group), T2 (ISA70VG), T3 (ISA70VG plus Nano-Se), T4 (Nano-Alum Hydroxide), T5 (Nano-Alum+Nano-Se), T6 (MF59), and T7 (MF59+Nano-Se). The vaccine was injected subcutaneously on day 21 in the back of the neck area. The blood samples were taken on days 14, 21, 28, 35, 42, and 49 post-vaccination. Serums of the samples were titrated by the haemagglutination inhibition (HI) test against Newcastle and Avian influenza. Based on the results, the highest HI test titers were observed for the T2 and T3 treatments, while the T6 and T7 treatments had the lowest titers. Moreover, regardless of the type of the adjuvants, adding Nano-Se increased the antibody titer in the vaccinated groups. In conclusion, a combination of the ISA70VG adjuvant and Nano-Se induced excellent antibody titers using bivalent ND+AI killed vaccine.

Thyroid dysfunction in patients with childhood-onset medulloblastoma or primitive neuroectodermal tumor

PURPOSE

We investigated the clinical characteristics of patients who developed thyroid dysfunction and evaluated the risk factors for hypothyroidism following radiotherapy and chemotherapy in pediatric patients with medulloblastoma or primitive neuroectodermal tumor (PNET).

METHODS

The medical records of 66 patients (42 males) treated for medulloblastoma (n=56) or PNET (n=10) in childhood between January 2000 and December 2014 at Seoul National University Children's Hospital were retrospectively reviewed. A total of 21 patients (18 high-risk medulloblastoma and 3 PNET) underwent high-dose chemotherapy and autologous stem cell rescue (HDCT/ASCR).

RESULTS

During the median 7.6 years of follow-up, 49 patients (74%) developed transient (n=12) or permanent (n=37) hypothyroidism at a median 3.8 years of follow-up (2.9-4.6 years). Younger age (&lt;5 years) at radiation exposure (P=0.014 vs. ≥9 years) and HDCT (P=0.042) were significantly predictive for hypothyroidism based on log-rank test. However, sex, type of tumor, and dose of craniospinal irradiation (less vs. more than 23.4 Gy) were not significant predictors. Cox proportional hazard model showed that both younger age (&lt;5 years) at radiation exposure (hazard ratio [HR], 3.1; vs. ≥9 years; P=0.004) and HDCT (HR, 2.4; P=0.010) were significant predictors of hypothyroidism.

CONCLUSION

Three-quarters of patients with pediatric medulloblastoma or PNET showed thyroid dysfunction, and over half had permanent thyroid dysfunction. Thus, frequent monitoring of thyroid function is mandatory in all patients treated for medulloblastoma or PNET, especially, in very young patients and/or high-risk patients recommended for HDCT/ASCR.