Showing papers on "SAIDS Vaccines published in 2007"
TL;DR: Atraumatic oral spray immunization with replication-deficient vectors can overcome the epithelial barrier, deliver the vaccine antigen to the mucosa-associated lymphatic tissue, and avoid induction of tolerance, providing a novel approach to circumvent acceptability problems of syringe and needle vaccines for children and in developing countries.
Abstract: The development of needle-free vaccines is one of the recently defined “grand challenges in global health” (H. Varmus, R. Klausner, R. Klausner, R. Zerhouni, T. Acharya, A. S. Daar, and P. A. Singer, Science 302:398-399, 2003). To explore whether a natural pathway to the inductive site of the mucosa-associated lymphatic tissue could be exploited for atraumatic immunization purposes, replication-deficient viral vector vaccines were sprayed directly onto the tonsils of rhesus macaques. Tonsillar immunization with viral vector vaccines encoding simian immunodeficiency virus (SIV) antigens induced cellular and humoral immune responses. Viral RNA levels after a stringent SIV challenge were reduced, providing a level of protection similar to that observed after systemic immunization with the same vaccines. Thus, atraumatic oral spray immunization with replication-deficient vectors can overcome the epithelial barrier, deliver the vaccine antigen to the mucosa-associated lymphatic tissue, and avoid induction of tolerance, providing a novel approach to circumvent acceptability problems of syringe and needle vaccines for children and in developing countries.
33 citations
TL;DR: It is demonstrated that immunization with hybrid HBcAg-epitope DNA vaccines is an effective strategy to increase the magnitude and breadth of HIV-specific CTL responses.
21 citations
TL;DR: The varicella-zoster virus (VZV) Oka vaccine offers potential as a recombinant vaccine against other pathogens and the ability of rSVV vaccines expressing SIV antigens to protect nonhuman primates against simian AIDS will be evaluated.
14 citations
TL;DR: The central nervous system of rhesus macaques was studied during series of vaccination experiments in which attenuated simian immunodeficiency virus (SIV), SIVmac239Δnef, was applied to the tonsils and the animals were later challenged with pathogenic Sivmac251 or SHIV/89.6P via tonsils or rectum.
Abstract: We studied the central nervous system (CNS) of rhesus macaques during series of vaccination experiments in which attenuated simian immunodeficiency virus (SIV), SIVmac239Deltanef, was applied to the tonsils and the animals were later challenged with pathogenic SIVmac251 or SHIV/89.6P via tonsils or rectum. The pathologic lesions were graded on a scale of 0-5. The lesions were in general very mild, with a score of 0.5, except for one case, in which the animal had progressed to simian AIDS (SAIDS) and had severe lesions of grade 4. Except for the SAIDS case, the most common lesions were meningitis, ependymitis, inflammation of choroid plexus, and astrocytosis. Invasion of the challenge virus, SIVmac251, and pathologic lesions were detected 4 days post infection. The main features of the pathological lesions were similar during short-term follow-up (4 days to 2 weeks) and long-term follow-up (23 to 56 weeks) after challenge. No significant difference was found between unvaccinated controls infected with the challenge viruses and vaccinated and challenged animals. The pathological lesions in the one SAIDS case consisted of extensive lesions of the white matter in connection with confluent ependymitis, indicating an invasion through the choroid plexus. The lesions were characterized by a myriad of multinucleated giant cells of macrophage origin, which showed, together with individual macrophages, strong labelling for viral RNA and proteins. Productive infection of astrocytes was a very rare finding. In three cases infected via tonsils with SIVmac239Deltanef without challenge, we detected expression of Nef-derived peptides, indicating a selective pressure for Nef functions in the CNS.
2 citations