Oral live attenuated human rotavirus vaccine (RotarixTM) offers sustained high protection against severe G9P[8] rotavirus gastroenteritis during the first two years of life in Brazilian children

In a large Phase III trial conducted in 10 Latin American countries, the safety and efficacy of the live attenuated monovalent rotavirus vaccine RIX4414 was evaluated in 15,183 healthy infants followed up during the first two years of life. Belém was the only site in Brazil included in this multicentre trial. The study in Belém included a subset of 653 infants who were followed up until 24 months of age for protection against severe rotavirus gastroenteritis. These subjects were randomly assigned in a 1:1 ratio to receive two doses of vaccine (n = 328) or two doses of placebo (n = 325) at approximately two and four months of age. Of the 653 enrolled infants, 23 dropped out during the study period. For the combined two-year period, the efficacy of RIX4414 was 72.3% [95% confidence interval (CI) 37.5-89.1%] against severe rotavirus-related gastroenteritis, reaching a protection rate of 81.8% (95% CI 36.4-96.6%) against circulating wild-type G9 rotavirus strains. It is concluded that two doses of RIX4414 are highly efficacious against severe rotavirus gastroenteritis in Belém during the first two years of life and provide high protection against the worldwide emergence and spread of G9P[8] strains.

Production of polyclonal antibody against recombinant ORF 112 L of rock bream (Oplegnathus fasciatus) iridovirus (RBIV) and in vitro neutralization.

Rock bream iridovirus (RBIV) is a causative agent of epizootics among cultured rock bream (Oplegnathus fasciatus) in Korea. In this study, the immunogenic property of ankyrin repeats gene (ORF 112L) from RBIV was evaluated to develop vaccines against RBIV. ORF 112L of RBIV was cloned into expression vector of pGEX-4T-1. The recombinant protein was successfully expressed using E. coli BL21 (DE3). The soluble recombinant RBIV protein was applied to affinity column for the purification of the protein. Mice were immunized by the injection of purified recombinant protein to produce polyclonal antibodies. EUSA was carried out to identify the immune reaction abilities of polyclonal antibody to recombinant protein. The antigenic property of this protein was evaluated by using in vitro neutralization with BF-2 cells. In neutralization test, BF-2 cells infected with the mixture of RBIV and antisera containing anti-GST-ORF 112L polyclonal antibody were healthy showing few cytopathic effect (CPE) similar with the negative control (without RBIV). These studies suggest that the protein from the ankyrin repeats gene, ORF 112L of RBIV may play an important role in the mechanism of infection. Also, it can be possible to develop protein or gene vaccines using ORF 112L against RBIV.

Comparison of antigenic sites of the envelope glycoprotein of the Iranian isolate of human T-cell leukemia virus type 1 with different subtypes of the virus

Human T-cell leukemia virus type 1 [HTLV-1] is an enveloped retrovirus, which is associated with a T-cell malignancy known as adult T-cell leukemia [ATL]. Variation in the HTLV-1 envelope nucleotide sequence has been extensively documented and has been used to classify HTLV-1 isolates into different subtypes. The virus occurs in at least 3 subtypes, which have been named A, B, and C. We conducted this study to compare the antigenic proprieties of the Iranian isolate of HTLV-1 with the homologous region of different subtypes of the virus. This study took place in the Department of Biology, College of Sciences, Shiraz University, Iran in 2005. The predicted antigenic sites and secondary structure of the envelope glycoprotein of HTLV-1, present in Iran, have been compared with the antigenic sites and secondary structure of the homologous domains in subtypes A, B, C of the virus. To predict the epitopes of glycoproteins, 21 different scales were used. The number of helices in the Iranian isolate was equal to the number of these regions in all 3 subtypes, but the number of beta-sheets was more than other viruses. One potential glycosylation site, on all these studied envelope glycoproteins, was predicted. Antigenic sites in the Iranian isolate were almost similar to subtype A of the virus and the Iranian isolate of HTLV-1 may be belongs to subtype A. Our results indicate the similarities and differences between the Iranian and other subtypes of HTLV-1. Antigenic sites represent potential candidates for use in a peptide vaccine against HTLV-1 glycoproteins and since most of the properties of a particular protein depend on its structural properties, this type of study can help in better understanding of HTLV-1 isolates present in Iran

A serological study of Chikungunya virus transmission in Yogyakarta, Indonesia: evidence for the first outbreak since 1982.

A study of epidemic transmission of Chikungunya virus (CHIK) was initiated in April 1999 in Yogyakarta, Indonesia. Three hundred seventeen volunteers from three kelurahans (sub-districts) were recruited. Anti-CHIK IgG antibodies were detected in 68% to 74% of cases and 28% to 32% of controls. In the kelurahan with no reported CHIK illness, 29% of cases and 28% of controls had anti-CHIK IgG antibodies. None of these cases demonstrated anti-CHIK IgM antibodies. In the two kelurahans with disease activity, anti-CHIK IgM antibodies were detected in 3% to 36% of cases, with the highest percentage from the kelurahan with recently reported cases. Ten percent of controls from Gowok had anti-CHIK IgM detected in their serum. Twelve acutely ill volunteers were later included from the kelurahan Pilahan for virus identification. Samples from two volunteers were culture- and RT-PCR-positive for CHIK. This is the first documentation of epidemic transmission of CHIK in Indonesia since 1982.

Structure of rotavirus particle: interaction of the inner capsid protein VP6 with the core polypeptide VP3

The structural relationship between VP6 (inner capsid polypeptide) and the viral core was studied using chemical cross-linking with dithiobis(succinimidyl propionate). Crosslinked single shelled and reconstituted rotavirus particles, suggest the existence of a complex organization of VP6 molecules in the inner capsid and a direct interaction with the core polypeptide VP3. The inhibition of the recovery of RNA polymerase activity associated with the reconstitution of the single shelled particle in the presence of antiVP6 monoclonal antibodies indicates that a VP6 domain between amino acids 56 and 58 seems to be important in viral transcription. A VP6 gene temperature-sensitive mutant (ts G) carrying a mutation affecting assembly of single shelled particles was used in reconstitution experiments. The mutant was able to recover RNA polymerase activity at restrictive temperature. Wild type cores or VP6 were able toreconstitute the particle with both the mutant cores and VP6. These results suggest the existence of various steps for the assembly of single shelled particles, where the VP6-VP3 interaction seems to be important for recovery of RNA polymerase activity