Comparison of IgA Antibody Titer Induced by Human-Bovine Rotavirus Candidate Vaccine with Bovine Rotavirus and Rotarix

Rotavirus (RV) is the most common cause of acute gastroenteritis in early childhood worldwide. Gastroenteritis is a preventable disease by the vaccine, and vigorous efforts were made to produce attenuated oral rotavirus vaccines. In recent years, despite the existence of three types of live attenuated rotavirus vaccines, several countries, such as China and Vietnam, have intended to produce indigenous vaccines based on rotavirus serotypes circulating among their population. In this study, the immunogenicity of homemade human-bovine reassortant RV candidate vaccine was tested in an animal model. Rabbits were randomly distributed into eight experimental groups with three animals per group. Afterward, three rabbits in each test group designated as P1, P2, and P3 were experimentally inoculated with the 106, 107, and 108 tissue culture infectious dose 50 (TCID50) of the reassortant virus, respectively. The N1 group received the reassortant rotavirus vaccine containing 107 TCID50+zinc. The N2, N3, and N4 groups received rotavirus vaccine strain, RV4 human rotavirus, and bovine rotavirus strain, respectively, and the control group received phosphate-buffered saline. It is noteworthy that three rabbits have been included in each group. The IgA total antibody titer was measured and evaluated by non-parametric Mann-Whitney and Kruskal-Wallis tests. The antibody titer produced in the studied groups did not significantly differ. The candidate vaccine showed immunogenicity, protectivity, stability, and safety. The findings of this study indicated a critical role of IgA production, which can induce immunity against a gastroenteritis viral pathogen. Regardless of purification, candidate reassortant vaccine and cell adapted animal strains could be used as a vaccine candidate for production.

Immunometabolism in human brucellosis: An emerging field of investigation

In recent years, extreme attention has been focused on the role of immunometabolism in the regulation of immune cell responses in healthy individuals during infection, autoimmunity, and cancer. In the infection biology area, it has been shown that there is a close relationship between the immune system and the host metabolic changes. Brucella species is an intracellular coccobacillus that infects humans and mammals, which led to brucellosis. Brucella species with host-specific evolutionary mechanisms allow it to hide from or manipulate cellular immunity and achieve intracellular persistence. Intracellular bacterial pathogens such as Brucella species also employ host cell resources to replicate and persist inside the host. Targeting these host systems is one promising strategy for developing novel antimicrobials to tackle intracellular infections. This study will summarize the role of metabolic reprogramming in immune cells and their relationship to brucellosis.

Distribution of the most common types of HPV in Iranian women with and without cervical cancer

Cervical cancer is an important cause of death in women worldwide. About 99.7% of all cervical cancers have been related to human papillomavirus, especially types 16 and 18. Types 6 and 11 cause genital warts. We aimed to determine the prevalence of common HPV genotypes among women in the general population and women with cervical cancer. A total of 571 healthy women cytology specimens and 113 tissue samples of cervical cancer were investigated using HPV type-specific primers. HPV DNA was detected in 24% of healthy women: 3.3% were positive for high-risk HPV and 11.6% for low-risk HPV. HPV6 (9.3%) had the highest prevalence followed by HPV11 (2.3%), HPV16 (1.8%), HPV18 (1.2%), and 9.1% of samples were positive for unknown types. Among cervical cancer samples, HPV DNA was found in 78.8% including 43.4% HPV16, 8% HPV18, and 27.4% an unknown HPV type. HPV6 and HPV11 were not detected in any cervical cancer cases and 21.2% were negative for HPV. We found no association between HPV-16/18 and age in cervical cancer. The prevalence of HPV infection is relatively high in Iran without vaccination backgrounds. HPV DNA screening and vaccination programs can prevent cervical cancer and health problems caused by genital warts.

Comparison of methylation patterns of E6 gene promoter region in the low-risk and high-risk human papillomavirus

BACKGROUND AND OBJECTIVES

Cervical cancer is an important cause of death in women worldwide (1, 2). Cancer is a disease that may be caused by many factors that affect gene activity through genetic and epigenetic changes like DNA methylation. DNA promoter methylation contributes to the chromatin conformation that may be repressing transcription of the human papilloma virus type16 (HPV-16), which is prevalent in the etiology of cervical carcinoma. In the present study, we aimed to investigate DNA methylation target sites in promoter region of both high-risk and low risk HPVs.

MATERIALS AND METHODS

Methylation pattern of E6 promoter in low-risk HPV (type 11) and high-risk HPV (type 16 and 18) was examined by Bisulfite Sequencing PCR (BSP) method.

RESULTS

Based on the results, methylation status of high-risk and low-risk HPV-E6 promoter is different. It was revealed that CpG dinucleotides were unmethylated in type 16 and 18 target sequences, whereas in HPV-E6 type 11 all of CpG dinucleotides were methylated except one of them.

CONCLUSION

The result suggested that a significant correlation between methylation status and HPV-induced cervical carcinogenesis, and promoter of HPV-16 and 18 E6 has minimal methylation in comparison with low-risk HPV-11.

Molecular and biological characterization of the human-bovine rotavirus-based reassortant rotavirus

Rotaviruses (RV) are the leading cause of acute infantile gastroenteritis, associated with elevated mortality in low-income countries. Morbidity and mortality, length and rates of hospitalization due to RV gastroenteritis are dropping. Improving the quality of newborns life is an ongoing challenge for health-care providers. In this study, homemade reassortant human-bovine rotavirus was developed and biological activity and molecular characterization of candidate vaccine were evaluated for the vaccine stability. Virus titration and purification of reassortant rotavirus strains were evaluated by plaque assays, electropherotyping. The genetic stability after first, third and sixth passage was by sequencing. Due to WHO recommendation, developingment of national capacity for vaccine production in appropriate quantities and at affordable prices is the cornerstone of developing global vaccination policies. Such studies are critical to producing national vaccines and modeling herd protection.

Novel, In-House, SYBR Green Based One-Step rRT-PCR: Rapid and Accurate Diagnosis of Crimean-Congo Hemorrhagic Fever Virus in Suspected Patients From Iran

BACKGROUND

The Crimean-Congo hemorrhagic fever (CCHF) virus causes severe disease in humans, with a high mortality rate. Since, there is no approved vaccine or specific treatment for CCHF, an early and accurate diagnosis, as well as reliable surveillance, is essential for case management and patient improvement.

OBJECTIVES

For this research, our aim was to evaluate the application of a novel SYBR Green based one-step real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) assay for the in-house diagnosis of the CCHF virus.

PATIENTS AND METHODS

In this experimental study, the highly conserved S-region sequence of the CCHF viral genome was first adapted from GenBank, and the specific primers targeting this region were designed. Then, the viral RNA was extracted from 75 serum samples from different patients in eastern Iran. The sensitivity and specificity of the primers were also evaluated in positive serum samples previously confirmed to have the CCHF virus, by this one-step rRT-PCR assay, as well as a DNA sequencing analysis.

RESULTS

From a total of 75 suspected serum samples, 42 were confirmed to be positive for CCHF virus, with no false-positives detected by the sequencing results. After 40 amplification cycles, the melting curve analysis revealed a mean melting temperature (Tm) of 86.5 ± 0.6°C (quite different from those of the primer-dimers), and the positive samples showed only a small variation in the parameters. In all of the positive samples, the predicted length of 420 bp was confirmed by electrophoresis. Moreover, the sensitivity test showed that this assay can detect less than 20 copies of viral RNA per reaction.

CONCLUSIONS

This study showed that this novel one-step rRT-PCR assay is a rapid, reliable, repeatable, specific, sensitive, and simple tool for the detection of the CCHF virus.