Iranian Journal of Virology
Volume:4 Issue: 3, 2010

Several drugs are being used in treatment of HSV infection in human but still introducing an effective safe drug is desirable. We investigated the inhibitory effect of morphine on replication of HSV in vitro. The results indicated that a concentration of up to 200 ug/ml morphine had a limited effect on Vero cell viability. At this concentration the growth of HSV was inhibited considerably and after the third passage in presence of morphine it was completely diminished. Presence of viral antigens in infected cells in presence of morphine by IF staining showed that after the first passage a small number of infected cells contained viral proteins and at the third passage no cells with viral antigen was observed. This was confirmed by page and immunobloting techniques. Electron microscopy observation in cellular section indicated that there was no virus present in treated cells as compared with control untreated infected cells.

Vaccine is available, but fetal infection with rubella virus is still a main cause of congenital birth defects and mental retardation in many countries. Mass vaccination campaigns and Expanded Program of Immunization (EPI) have increased vaccine coverage in the world with a substantial impact on the reduction of rubella infections, such as Congenital Rubella Syndrome (CRS). The present study was performed to evaluate the immune status against rubella before and after the mass campaign vaccination on 22 Dec. 2003. A total of 320 sera samples collected from the healthy subjects before (group a) and after the vaccination (group b) as well as 80 paired sera (group c) collected from other target group as a panel were tested for the presence of anti-rubella antibody using HI test. Following the mass campaign vaccination 98.1% of the population has anti -rubella antibody, whereas 92.2% were positive before the vaccination. In group c (the paired examined subjects) 98.75% have gained anti -rubella antibody. Seronegative individuals were considered as high-risk members, which must be vaccinated again.

In humans the group A rotaviruses are associated with endemic diarrhea in children under the age of 5, leading to approximately 800,000 deaths every year. Introduction of rotavirus vaccines into childhood immunization programs can contribute to substantial reduction in mortality from rotavirus gastroenteritis in developing countries and virtually eliminating hospitalizations due to rotavirus gastroenteritis, a heavy burden in developed countries. A reassortant Rhesus-human rotavirus vaccine, Rotashield was manufactured and marketed in 1998. Nine months later a small number of cases of intussusceptions were identified, leading to the withdrawal of vaccine. Important questions remain for these oral live vaccines related with safety and side effects as well as production costs, thus development of second generation of nonreplicating rotavirus vaccine should be considered as an alternative to live vaccines. VP7 is major outer capsid glycoprotein; can induce production of neutralizing antibodies. Regarding these concepts we cloned VP7 gene of SA11 rotavirus in pGEM vector for future expression. With large scale expression and purification of VP7 protein, it will be convenient to study VP7 antigenic, immunogenic, biologic functions and its potential for vaccine development. BSC-1 cells were grown as a monolayer. Simian rotavirus, SA11 was cultured. Oligonucleotide forward and reverse primers, specific for gene segment 9 which encodes VP7, were synthesized, according to dsRNA gene segment 9 of simian rotavirus SA11 sequence data at NCBI GeneBank. Rotavirus ds-RNA was extracted and used as template for reverse transcription to synthesize cDNA from both viral strands. cDNA product of RT-PCR was cloned into pGEM@-5Zf(-) vector and the results showed that rotavirus genome segment 9 was cloned into pGEM@-5Zf(-) vector and confirmed by restriction enzyme and sequencing. Sequencing result was analyzed by BLAST software showing 100% homology with 91 SA11 rotavirus genome segment in NCBI GeneBank.

Since 1998, Iranian poultry industry has been affected by avian influenza (AI) virus, subtype H9N2. The association of high mortality and case report of H5N1 and H9N2 influenza virus in wild birds in recent years raised the suspicion of a possible new genetic modified AI virus. Partial nucleotide sequences and deduced amino acid of hemagglutinin (HA) genes of 4 H9N2 influenza viruses isolated from broilers in Iran in 2007 were genetically analyzed. The isolates possessed two types of amino acid motif -R-S-S-RlG-L- and -R-S-N-RlG-L- at the cleavage site of HA. "-R-S-N-RlG-L in Iranian isolates is the same as the motif previously reported in Israel. Glycosylation site of the virus has been missed in some isolates. Receptor binding site of the isolates were found similar to the human H9N2 isolates. Based on published reports for high similarity of H9N2 with human H5N1 isolates, it is important to consider the potential of Iranian avian influenza viruses to infect human.

Rotaviruses are one of the main causative agents of acute viral gastroenteritis in both young human and animals. Several methods have been used for diagnosis of rotavirus infection. Most of these methods are not easily available in Iran. In our study attempt was made to develop a method which could replace the commercially imported Kit. Rota virus was purified and nonspecific antibody was prepared. The gamma globulin fraction was purified and conjugated to horse radish peroxidase. Plates were coated with anti-rotavirus gamma globulin and were used for the ELISA method. This method was used for the detection of Rotavirus in clinical specimen. Electron microscopy method was used on the same specimen for observation of Rotavirus particles. It was found that the developed ELISA Kit had a relatively high sensitivity and specificity as compared with Electron Microscopy.

Peganum harmala L. (Zygophylaceae) has been used in a variety of practical applications in medical science. Our objective in the current study was to determine the effects of the seed extract on Herpes simplex virus type 1 (HSV -1) replication in Vero cells. Different concentrations (100, 500, 571, 667, 800 and 1000 ug/ml) of the extract were examined. Experiments were carried out using Vero cells. This method was used for the detection of Rotavirus in clinical specimen. Electron microscopy method was used on the same specimen for observation of Rotavirus particle P.harmala seed extract was found to be non-toxic to Vero cells up to a concentration of 667 ug/ml, The antiviral activity of nontoxic concentration against HSV -1 was tested. The replication of HSV -1 was inhibited, indicating that the P.harmala L. extract contains an anti-HSV-l substance.

Influenza virus is a major pathogen involved in respiratory illnesses during winter seasons. A variety of diagnostic methods have been developed to identify influenza viruses in clinical specimen. Nasal and pharyngeal samples taken from patients were inoculated into Madin-Darby canine kidney (MOCK) cells and embryonated chicken eggs (ECEs). The culture media was assayed for hemagglutination (HA). Tissue culture supernatant and clinical specimens were used for RNA extraction, followed by reverse transcriptase-polymerase chain reaction (RT-PCR) using specific primers for influenza virus typing and subtyping. 21% of the samples were positive by RT-PCR while only 8.7% and 3.5% were positive by culturing in MOCK and ECE respectively. This study demonstrated that RT-PCR is more effective and sensitive than tissue culture for the diagnosis of influenza virus infection.

Measles remains one of the leading causes of childhood morbidity and mortality in developing countries and is still a major public health concern in developed countries. Although live attenuated vaccine is used throughout the world, out breaks of disease still occur in many countries including Iran. The present study was performed to evaluate the immune status against measles after the mass campaign vaccination in 2003. In this study, Approximately 172 sera were analysed by ELISA and HI tests. The results indicated, 162 were positive (94.2%) and 10 were negative (5.8%) by HI test and 165 were positive (95.5%) and 7 were negative (4.1%) by the ELISA test. Understanding measles outbreaks that occur after the initiation of measles elimination efforts will be critical in refining the strategies for measles elimination.

Glycoprotein B (gB) is among the most important immunogenic proteins of HSV-1 that is now being used as recombinant vaccine to induce protectively against the virus. It is believed that gB is responsible for induction of neutralizing antibody and up to 90% of CTL (Cytotoxic T Cell) activity against HSV-1 in some haplotypes. In the present study the antibody titer induced by a gB based DNA vaccine and the protective effect of the candidate vaccine in BALB/c mice in comparison with those induced by the whole virus were evaluated. DNA plasmid carrying full-length of gB-1 was constructed and its ability to express the protein was confirmed by immunofluorescence test. Humoral immune response and protective effect of the constructed vector were evaluated in BALB/c mice. The neutralizing antibody titer induced by the DNA vaccine was significantly lower than the one induced by the whole virus, although, both of vaccines could confer 100% protectively against HSV-1 challenge.

Lemon Balm L (Lamiaceae) has been used in a variety of practical applications in medical sciences. Its antiviral activity against herpes simplex virus type-1 (HSV-1) was investigated in cell culture. Lemon Balm hydroalcoholic extract was found to be non-toxic to Vero cells up to concentration 800 ug/ml and inhibited the growth and development of HSV-1 in dose-dependent manner in Vero cells. In order to study the possible mechanisms of the antiviral activity of Lemon Balm extract, cells were treated with extract before, during and after infection, and the viral titers were tested by TCID50 assay. The antiviral effects in treatment of post and during virus infection were more remarkable than the treatment of preinfection. For further investigation indirect immunofluorescence technique was used to elucidate the antiviral mechanism of the extract by infecting Vero cells at different times and monitoring the synthesis of viral proteins. Although the precise mechanism has not yet to be defined, our work indicated that lemon Balm L. extract could inhibit growth and development of HSV-1 in cells in vitro.