11 research outputs found

    HIV-1 remission following CCR5Δ32/Δ32 haematopoietic stem-cell transplantation

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    HIV-1 cure remains elusive with only one reported case a decade ago1,2. Termed the 'Berlin patient', the individual underwent two allogeneic haematopoietic stem-cell transplantation (allo-HSCT) procedures using a donor with a homozygous mutation in the HIV coreceptor CCR5 (CCR5Δ32/Δ32) to treat his acute myeloid leukaemia. Total body irradiation was given with each HSCT. Critically, it is unclear which treatment or patient parameters contributed to this only documented case of long-term HIV remission. Here we show that HIV-1 remission may be possible with a less aggressive and toxic approach. An HIV-1-infected adult underwent allo-HSCT for Hodgkin's lymphoma using cells from a CCR5Δ32/Δ32 donor. He experienced mild gut graft versus host disease. Antiretroviral therapy was interrupted 16 months after transplantation. HIV-1 remission has been maintained through a further 18 months. Plasma HIV-1 RNA has been undetectable at less than 1 copy per millilitre along with undetectable HIV-1 DNA in peripheral CD4 T lymphocytes. Quantitative viral outgrowth assay from peripheral CD4 T lymphocytes shows no reactivatable virus using a total of 24 million resting CD4 T cells. CCR5-tropic, but not CXCR4-tropic viruses were identified in HIV-1 DNA from CD4 T cells of the patient prior to transplant. CD4 T cells isolated from peripheral blood post-transplant did not express CCR5 and were only susceptible to CXCR4-tropic virus ex vivo. HIV-1 Gag-specific CD4 and CD8 T cell responses were lost after transplantation, whereas cytomegalovirus (CMV)-specific responses were detectable. Likewise, HIV-1-specific antibodies and avidities fell to levels comparable to those in the Berlin patient following transplantation. Although at 18 months post-treatment interruption it is premature to conclude that this patient has been cured, these data suggest that single allo-HSCT with homozygous CCR5Δ32 donor cells may be sufficient to achieve HIV-1 remission with reduced intensity conditioning and no irradiation, and the findings further support the development of HIV remission strategies based on preventing CCR5 expression

    Two genomes of highly polyphagous lepidopteran pests (<i>Spodoptera frugiperda</i>, Noctuidae) with different host-plant ranges

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    Emergence of polyphagous herbivorous insects entails significant adaptation to recognize, detoxify and digest a variety of host-plants. Despite of its biological and practical importance - since insects eat 20% of crops - no exhaustive analysis of gene repertoires required for adaptations in generalist insect herbivores has previously been performed. The noctuid moth Spodoptera frugiperda ranks as one of the world’s worst agricultural pests. This insect is polyphagous while the majority of other lepidopteran herbivores are specialist. It consists of two morphologically indistinguishable strains (“C” and “R”) that have different host plant ranges. To describe the evolutionary mechanisms that both enable the emergence of polyphagous herbivory and lead to the shift in the host preference, we analyzed whole genome sequences from laboratory and natural populations of both strains. We observed huge expansions of genes associated with chemosensation and detoxification compared with specialist Lepidoptera. These expansions are largely due to tandem duplication, a possible adaptation mechanism enabling polyphagy. Individuals from natural C and R populations show significant genomic differentiation. We found signatures of positive selection in genes involved in chemoreception, detoxification and digestion, and copy number variation in the two latter gene families, suggesting an adaptive role for structural variation

    Preparation and properties of nanophase (Ce, Zr, Pr)O2-doped alumina coating on cordierite ceramic honeycomb for three-way catalysts

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    Nanophase (Ce, Zr, Pr)O2-doped alumina coatings were prepared by impregnating the cordierite ceramic honeycomb in the sol or in the slurry of already calcined powder, respectively. The effects of preparation methods on the crystal phase, texture, oxygen storage capacity (OSC), reducibility, surface morphology and thermal stability of coatings were investigated by X-ray diffraction (XRD), the Brunauer Emmet Teller (BET) method, the oxygen pulsing technique, H2-temperature-programmed reduction (H2-TPR) and scanning electron microscopy (SEM). These nanophase (Ce, Zr, Pr)O2-doped alumina coatings were used as supports to prepare Pd-only three-way catalysts, and evaluated with respect to catalytic activities. The results indicate that the nanophase (Ce, Zr, Pr)O2-doped alumina coatings prepared by the two methods have high thermal stability. However, the coating derived from the sol shows better crystalline structure, texture, reducibility and oxygen storage capacity than the coating derived from the slurry. SEM observation shows that the morphology of the coating derived from the sol is uniform and smooth. The Pd-only catalyst derived from the sol exhibits high three-way catalytic activity at low temperature and thermal stability, suggesting a great potential for applications
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