A randomized, double-blind trial to evaluate immunogenicity and safety of 13-valent pneumococcal conjugate vaccine given concomitantly with trivalent influenza vaccine in adults aged ≥65 years

AbstractThis randomized, double-blind study evaluated concomitant administration of 13-valent pneumococcal conjugate vaccine (PCV13) and trivalent inactivated influenza vaccine (TIV) in adults aged ≥65 years who were naïve to 23-valent pneumococcal polysaccharide vaccine. Patients (N=1160) were randomized 1:1 to receive PCV13+TIV followed by placebo, or Placebo+TIV followed by PCV13 at 0 and 1 months, with blood draws at 0, 1, and 2 months. Slightly lower pneumococcal serotype-specific anticapsular polysaccharide immunoglobulin G geometric mean concentrations were observed with PCV13+TIV relative to PCV13. Concomitant PCV13+TIV demonstrates acceptable immunogenicity and safety compared with either agent given alone

BcePred: prediction of continuous B-cell epitopes in antigenic sequences using physico-chemical properties

Abstract. A crucial step in designing of peptide vaccines involves the identification of B-cell epitopes. In past, numerous methods have been developed for predicting continuous B-cell epitopes, most of these methods are based on physico-chemical properties of amino acids. Presently, its difficult to say which residue property or method is better than the others because there is no independent evaluation or benchmarking of existing methods. In this study the performance of various residue properties commonly used in B-cell epitope prediction has been evaluated on a clean dataset. The dataset used in this study consists of 1029 non-redundant B cell epitopes obtained from Bcipep database and equally number of non-epitopes obtained randomly from SWISS-PROT database. The performance of each residue property used in existing methods has been computed at various thresholds on above dataset. The accuracy of prediction based on properties varies between 52.92 % and 57.53%. We have also evaluated the combination of two or more properties as combination of parameters enhance the accuracy of prediction. Based on our analysis we have developed a method for predicting B cell epitopes, which combines four residue properties. The accuracy of this method is 58.70%, which is slightly better than any single residue property. A web server has been developed to predict B cell epitopes in an antigen sequence. The server is accessible fro

An Assessment of the Role of Chimpanzees in AIDS Vaccine Research

Prior to Simian Immunodeficiency Virus (SIV)-infected macaques becoming the ‘model of choice’ in the 1990s, chimpanzees were widely used in AIDS vaccine research and testing. Faced with the continued failure to develop an effective human vaccine, some scientists are calling for a return to their widespread use. To assess the past and potential future contribution of chimpanzees to AIDS vaccine development, databases and published literature were systematically searched to compare the results of AIDS vaccine trials in chimpanzees with those of human clinical trials, and to determine whether the chimpanzee trials were predictive of the human response. Protective and/or therapeutic responses have been elicited in chimpanzees, via: passive antibody transfer; CD4 analogues; attenuated virus; many types and combinations of recombinant HIV proteins; DNA vaccines; recombinant adenovirus and canarypox vaccines; and many multi-component vaccines using more than one of these approaches. Immunogenicity has also been shown in chimpanzees for vaccinia-based and peptide vaccines. Protection and/or significant therapeutic effects have not been demonstrated by any vaccine to date in humans. Vaccine responses in chimpanzees and humans are highly discordant. Claims of the importance of chimpanzees in AIDS vaccine development are without foundation, and a return to the use of chimpanzees in AIDS research/vaccine development is scientifically unjustifiable

Detection of unusual mutation within the VP1 region of different re-isolates of poliovirus Sabin vaccine

In the present study, a genomic analysis of full VP1 sequence region of 15 clinical re-isolates (14 healthy vaccinees and one bone marrow tumor patient) was conducted, aiming to the identification of mutations and to the assessment of their impact on virus fitness, providing also insights relevant with the natural evolution of Sabin strains. Clinical re-isolates were analyzed by RT-PCR, sequencing and computational analysis. Some re-isolates were characterized by an unusual mutational pattern in which non-synonymous mutations outnumbered the synonymous ones. Furthermore, the majority of amino-acid substitutions were located in the capsid exterior, specifically in N-Ags, near N-Ags and in the north rim of the canyon. Also mutations, which are well-known determinants of attenuation, were identified. The results of this study propose that some re-isolates are characterized by an evolutionary pattern in which non-synonymous mutations with a direct phenotypic impact on viral fitness are fixed in viral genomes, in spite of synonymous ones with no phenotypic impact on viral fitness. Results of the present retrospective characterization of Sabin clinical re-isolates, based on the full VP1 sequence, suggest that vaccine-derived viruses may make their way through narrow breaches and may evolve into transmissible pathogens even in adequately immunized populations. For this reason increased poliovirus laboratory surveillance should be permanent and full VP1 sequence analysis should be conducted even in isolates originating from healthy vaccinees