Project description:Indian rhesus macaques are arguably the most reliable animal models in AIDS research. In this species the MHC class I allele Mamu-B*08, among others, is associated with elite control of SIV replication. A similar scenario is observed in humans where the expression of HLA-B*27 or HLA-B*57 has been linked to slow or no progression to AIDS after HIV infection. Despite having large differences in their primary structure, it has been reported that HLA-B*27 and Mamu-B*08 display peptides with sequence similarity. To fine-map the Mamu-B*08 binding motif and assess its similarities with that of HLA-B*27 we affinity purified the peptidomes bound to these MHC class I molecules and analyzed them by LC-MS/MS identifying several thousands of endogenous ligands. Sequence analysis of both sets of peptides revealed a degree of similarity in their binding motifs, especially at peptide position 2 (P2) where arginine was present in the vast majority of ligands of both allotypes. In addition, several differences emerged from this analysis: (i) ligands displayed by Mamu-B*08 tended to be shorter and to have lower molecular weight, (ii) Mamu-B*08 showed a higher preference for glutamine at P2 as a suboptimal binding motif and (iii) the second major anchor position, found at P-omega, was much more restrictive in Mamu-B*08. In this regard, HLA-B*27 bound efficiently peptides with aliphatic, aromatic (including tyrosine) and basic C-terminal residues while Mamu-B*08 preferred peptides with leucine and phenylalanine in this position. These results deepen our understanding of the molecular basis of the presentation of peptides by Mamu-B*08 and can contribute to the detection of novel SIV epitopes restricted by this allotype.
Project description:Molecular basis for CNS dysfunction in simian immunodeficiency virus-infected rhesus monkeys. We used microarrays to identify differentially expressed genes in chronic simian immunodeficiency virus-infected rhesus monkeys. Frontal lobe samples were obtained from control and SIV infected animals for RNA extraction and hybridization on Affymetrix microarrays. We sought to better understand the gene that changes in gene expression with SIV infection in the frontal lobe.
Project description:Strain 68-1–derived Rhesus Cytomegalovirus (RhCMV) vectors expressing simian immunodeficiency virus (SIV) proteins (RhCMV/SIV) are able to elicit and maintain cellular immune responses that stringently control and subsequently clear a mucosal challenge with highly pathogenic SIV in 50-60% of vaccinated rhesus monkeys (RMs). Here, we utilize whole blood transcriptomic profiling to identify host responses correlated to RhCMV/SIV efficacy.
Project description:Splenic tissue was isolated from four adult male Indian-origin Rhesus monkeys serologically positive for non-pathogenic SHIV 89.6 and from matched uninfected four adult male Indian-origin Rhesus monkeys respectively. The corresponding RNA was processed by cDNA microarray analysis. Keywords: SIV infection
Project description:Oligodendrocytes and their progenitors upregulate MHC pathways in response to inflammation, but the frequency of this phenotypic change is unknown and the features of these immune oligodendroglia are poorly defined. We generated MHC class I and II transgenic reporter mice to define their dynamics in response to inflammatory demyelination, providing a means to monitor MHC activation in diverse cell types in living mice and define their roles in aging, injury and disease.
Project description:A mutant simian immunodeficiency (SIVmac239) virus, found to be selected within chronically SIV-infected Burmese rhesus monkeys with relatively enhanced SIV-specific antibody responses, was reconstituted as a molecular clone. The virus (SIV Nef G63E) was then subjected to a preliminary analysis for their intracellular signal transduction and gene expression modulation patterns (as compared with wild type SIVmac239) within infected CD4+ T cells. Analysis implicated that the mutant virus had a moderately enhanced cytopathic phenotype. A SIV mutation (SIVmac239 Nef G63E) found to be enriched in rhesus monkeys with enhanced SIV-specific antibody responses was reconstituted on a pBR-based SIV molecular clone pBRmac239. HSC-F cynomolgus macaque central memory Th2-like T cells were infected with mutant and wild type SIVmac239 at MOI 5 in triplicate along with uninfected controls (i.e. a total of 9 samples) for 24 hours and subjected to analysis of their gene expression patterns.