A problem in the search for an efficient vaccine against dengue virus is the immunodominance of the fusion loop epitope (FLE), a segment of the envelope protein E that is buried at the interface of the E dimers coating mature viral particles. Anti-FLE antibodies are broadly cross-reactive but poorly neutralizing, displaying a strong infection enhancing potential. FLE exposure takes place via dy...

The choice of which determinants of a whole Ag will be presented on cell surface MHC class II molecules after uptake and processing by APC is the result of the interplay between structural characteristics of the Ag and the processing machinery of the APC. In this study, we demonstrate that introduction of a dibasic motif adjacent to a subdominant determinant enhances the presentation of this de...

Induction of high levels of broadly reactive cytotoxic T lymphocytes (CTL) remains a promising approach for an effective HIV-1 vaccine. We have developed a novel genetic-based vaccine strategy that encodes consensus overlapping peptide sets from all HIV-1 proteins scrambled together. This synthetic scrambled antigen vaccine (SAVINE) strategy has significant advantages, e.g. capacity to encode m...

Although of low morbidity, sweating sickness is readily induced in calves by infestation with positive Hyalomma truncatum adult ticks. This epitheliotrophic disease has no specific cure except by the administration of hyperimmune serum obtained from animals which have recovered and are subsequently immune to the disease. Treatment with hyperimmune serum, however, has associated problems of dono...

The action of TdT on mouse TCR genes accounts for approximately 90% of T cell repertoire diversity. We report that in TdT-/- mice, total T(CD8+) responses to influenza and vaccinia viruses are reduced by approximately 30% relative to wild-type mice. We find that T(CD8+) responses to three subdominant influenza virus determinants are reduced to background values in TdT-/- mice while responses to...

Immunodominant epitopes are few selected epitopes from complex antigens that initiate T-cell responses. Here to provide further insights into this process, we use a reductionist cell-free antigen-processing system composed of defined components. We use the system to characterize steps in antigen processing of pathogen-derived proteins or autoantigens and we find distinct paths for peptide proce...

The envelope glycoprotein of small ruminant lentiviruses (SRLV) is a major target of the humoral immune response and contains several linear B-cell epitopes. We amplified and sequenced the genomic segment encoding the SU5 antigenic site of the envelope glycoprotein of several SRLV field isolates. With synthetic peptides based on the deduced amino acid sequences of SU5 in an enzyme-linked immuno...