Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Mannitol-induced gold nanoparticle aggregation for the ligand-free detection of viral particles

Traditional virus detection methods require ligands that bind to either viral capsid proteins or viral nucleic acids. Ligands are typically antibodies or oligonucleotides and they are expensive, have limited chemical stability, and can only detect one specific type of virus at a time. Here, the biochemical surface properties of viruses are exploited for ligand-free, nonspecific virus detection. It has been found that the osmolyte mannitol can preferentially aggregate virus, while leaving proteins in solution. This led to the development of a ligand-free detection of virus using gold nanoparticle (AuNP) aggregation. Porcine parvovirus (PPV) was incubated with AuNPs and aggregation of the PPV-AuNP complex with mannitol was detected by dynamic light scattering (DLS). The lowest detectable concentration of PPV was estimated to be 106 MTT50 per mL, which is lower than standard antibody assays. PPV was also detected when swabbed from a dry surface and in the presence of a protein solution matrix. The enveloped bovine viral diarrhea virus (BVDV) was also detected using mannitol-induced aggregation of BVDV-coated AuNPs. The lowest detectable concentration of BVDV was estimated to be 104 MTT50 per mL. This demonstrates that gold nanoparticle aggregation can detect virus without the use of specific ligands

Frequent Development of Broadly Neutralizing Antibodies in Early Life in a Large Cohort of Children With Human Immunodeficiency Virus

BackgroundRecent studies have indicated that broadly neutralizing antibodies (bnAbs) in children may develop earlier after human immunodeficiency virus (HIV) infection compared to adults.MethodsWe evaluated plasma from 212 antiretroviral therapy-naive children with HIV (1-3 years old). Neutralization breadth and potency was assessed using a panel of 10 viruses and compared to adults with chronic HIV. The magnitude, epitope specificity, and immunoglobulin (Ig)G subclass distribution of Env-specific antibodies were assessed using a binding antibody multiplex assay.ResultsOne-year-old children demonstrated neutralization breadth comparable to chronically infected adults, whereas 2- and 3-year-olds exhibited significantly greater neutralization breadth (P = .014). Likewise, binding antibody responses increased with age, with levels in 2- and 3-year-old children comparable to adults. Overall, there was no significant difference in antibody specificities or IgG subclass distribution between the pediatric and adult cohorts. It is interesting to note that the neutralization activity was mapped to a single epitope (CD4 binding site, V2 or V3 glycans) in only 5 of 38 pediatric broadly neutralizing samples, which suggests that most children may develop a polyclonal neutralization response.ConclusionsThese results contribute to a growing body of evidence suggesting that initiating HIV immunization early in life may present advantages for the development of broadly neutralizing antibody responses

History of pre-eclampsia does not appear to be a risk factor for vascular phenotype in women with systemic sclerosis

International audienceBACKGROUND: Vascular phenotype is associated with a poor prognosis in systemic sclerosis (SSc). The identification of its risk factors could facilitate its early detection. OBJECTIVES: To explore risk factors for a vascular phenotype of SSc, among them a history of pre-eclampsia. METHODS: This observational multicentre case-control study enrolled adult women fulfilling European Alliance of Associations for Rheumatology 2013 diagnosis criteria for SSc and having a pregnancy history≥6 months before SSc diagnosis in 14 French hospital-based recruiting centres from July 2020 to July 2022. Cases had specific vascular complications of SSc defined as history of digital ischaemic ulcers, pulmonary arterial hypertension, specific cardiac involvement or renal crisis. Women with SSc were included during their annual follow-up visit and filled in a self-administered questionnaire about pregnancy. A case report form was completed by their physician, reporting data on medical history, physical examination, clinical investigations and current medication. The main outcome was the presence/absence of a personal history of pre-eclampsia before SSc diagnosis, according to the validated pre-eclampsia questionnaire. RESULTS: 378 women were included: 129 cases with a vascular phenotype and 249 matched controls. A history of pre-eclampsia was reported in 5 (3.9%) cases and 12 (4.8%) controls and was not associated with a vascular phenotype (OR=0.96, 95% CI 0.28 to 3.34, p=0.9). Besides, Rodnan skin score and disease duration≥5 years were risk factors for vascular phenotype. CONCLUSIONS: In women with SSc and a pregnancy history≥6 months before SSc, a history of pre-eclampsia is not associated with a vascular phenotype