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Beaume, N.

Publications and source records attributed to Beaume, N..

3 recordsLinked to original sources

VRC01 Selects Rare HIV Escape Mutations After Acquisition in Antibody-Mediated Prevention Trials

Broadly neutralizing antibodies (bnAbs) show promise in HIV prevention, yet viral escape remains a challenge. In the Antibody Mediated Prevention (AMP) trials, the CD4 binding site (CD4bs) bNAb VRC01 blocked acquisition by VRC01-sensitive strains. However, its influence on viral evolution post-acquisition is not fully understood. Here we analyzed >12,000 HIV env sequences from 47 participants from the AMP trials, identifying VRC01-mediated de novo escape mutations in 8 of 26 VRC01-treated participants but none in 21 placebo participants. These mutations were found at very low frequency (<1%) in global viruses. Escape mutations, primarily located in the Loop-D and {beta}23/V5 regions of Env, conferred cross-resistance to several CD4bs bnAbs, while more potent CD4bs bnAbs like N6 and 1-18 largely retained their activity. Our findings demonstrate that prophylactic VRC01 can select for viral escape after infection, underscoring the need for next-generation bnAbs with improved breadth and potency to enhance durability and efficacy of antibody-based HIV prevention.

microbiology↗

Influence of the broadly neutralizing antibody VRC01 on HIV breakthrough virus populations in antibody-mediated prevention trials

In the HIV antibody mediated prevention (AMP) trials, the broadly neutralizing antibody VRC01 demonstrated protective efficacy against new diagnoses with susceptible HIV strains. To understand how VRC01 shaped breakthrough infections, we performed deep sequencing on 172 participants in the placebo and treatment arms, generating 63,444 gag-{Delta}pol (2.5 kb) and 53,088 rev-env-{Delta}nef (3 kb) sequences. Sequences were classified into transmitted founder lineages (TFLs), and infections with multiple distinct lineages were determined. Multilineage infections were detected in [~]38% of participants in both the African (HVTN 703/HPTN 081) and Americas/Europe (HVTN 704/HPTN 085) cohorts, regardless of placebo or treatment group, or cohort. The high levels of multilineage infections could be attributed to minor lineages (<5% abundance) identified in 20% of participants. Infection with VRC01 discordant viruses (IC80s >3-fold different) was observed in 40% of multilineage infections, with a trend toward greater intra-host neutralization differences with increasing VRC01 dose (Jonckheere-Terpstra test, p=0.072). In six VRC01 treated participants who acquired both sensitive (IC80<1{micro}g/ml) and resistant viruses (IC80>3{micro}g/ml), the sensitive lineages declined over time. Recombination was pervasive, observed in 63% of multilineage infections at the time of HIV diagnosis. In one treated participant infected with VRC01 discordant lineages, recombinant viruses preferentially inherited the resistance mutation (binomial p=0.004). In conclusion, our in-depth analysis of breakthrough viruses in the AMP trials revealed a high frequency of multilineage infections, including infections with viruses with different VRC01 sensitivities. This analysis also highlights the role of recombination in shaping intra-host viral evolution and facilitating escape from VRC01. SignificanceThis work advances our understanding of the diversity of initial viral infection and evolution and in vivo activity of broadly neutralizing antibodies (bNAbs). Deep sequencing revealed [~]38% of HIV acquisitions with multiple transmitted founder lineages, higher than previous studies. These occurrences were similar in the placebo and VRC01 groups. Viral recombination among post-acquisition variants was common under antibody selection and appeared to favor resistant sequences in the treatment group. These data suggest as with single antiviral therapy, passive and active immunization of bNAbs should be directed at multiple antigen targets of HIV-1.

molecular biology↗

Rice Galaxy: an open resource for plant science

Background\n\nRice molecular genetics, breeding, genetic diversity, and allied research (such as rice-pathogen interaction) have adopted sequencing technologies and high density genotyping platforms for genome variation analysis and gene discovery. Germplasm collections representing rice diversity, improved varieties and elite breeding materials are accessible through rice gene banks for use in research and breeding, with many having genome sequences and high density genotype data available. Combining phenotypic and genotypic information on these accessions enables genome-wide association analysis, which is driving quantitative trait loci (QTL) discovery and molecular marker development. Comparative sequence analyses across QTL regions facilitate the discovery of novel alleles. Analyses involving DNA sequences and large genotyping matrices for thousands of samples, however, pose a challenge to non-computer savvy rice researchers.\n\nFindings\n\nWe adopted the Galaxy framework to build the federated Rice Galaxy resource, with shared datasets, tools, and analysis workflows relevant to rice research. The shared datasets include high density genotypes from the 3,000 Rice Genomes project and sequences with corresponding annotations from nine published rice genomes. Rice Galaxy includes tools for designing single nucleotide polymorphism (SNP) assays, analyzing genome-wide association studies, population diversity, rice-bacterial pathogen diagnostics, and a suite of published genomic prediction methods. A prototype Rice Galaxy compliant to Open Access, Open Data, and Findable, Accessible, Interoperable, and Reproducible principles is also presented.\n\nConclusions\n\nRice Galaxy is a freely available resource that empowers the plant research community to perform state-of-the-art analyses and utilize publicly available big datasets for both fundamental and applied science.

bioinformatics↗