Breast milk and in utero transmission of HIV-1 select for envelope variants with unique molecular signatures.

Background: Mother-to-child transmission of human immunodeficiency virus-type 1 (HIV-1) poses a serious health threat in developing countries, and adequate interventions are as yet unrealized. HIV-1 infection is frequently initiated by a single founder viral variant, but the factors that influence particular variant selection are poorly understood.

Results: Our analysis of 647 full-length HIV-1 subtype C and G viral envelope sequences from 22 mother-infant pairs reveals unique genotypic and phenotypic signatures that depend upon transmission route.

A Conserved Glycan in the C2 Domain of HIV-1 Envelope Acts as a Molecular Switch to Control X4 Utilization by Clonal Variants with Identical V3 Loops.

Nearly all persons newly infected with HIV-1 harbor exclusively CCR5-using virus. CXCR4-using variants eventually arise in up to 50% of patients infected with subtypes B or D. This transition to efficient CXCR4 utilization is often co-incident with progression to AIDS.

Human parechovirus central nervous system infections in southern California children.

Background: Human parechoviruses (hPeV) are increasingly recognized as significant etiological agents for meningoencephalitis especially in young children, but testing of cerebrospinal fluid (CSF) for hPeV by PCR is not routinely performed.

Methods: We used real-time reverse transcriptase PCR for detection of serotypes 1-6 in CSF samples of 440 children who underwent a lumbar puncture to exclude an infectious etiology of their clinical presentation. We then compared the prevalence and clinical presentation of children with hPeV-positive CSF with that of children with enterovirus (EV)-positive CSF.

Coverage of primary mother-to-child HIV transmission isolates by second-generation broadly neutralizing antibodies.

Objectives And Design: A vaccine capable of providing cross-clade, sterilizing protection has been the holy grail of HIV-1 prevention and control since the beginning of the pandemic. A major component of this effort has been the identification and characterization of broadly neutralizing antibodies (bNAbs). Recent advances in bNAb isolation, structure-based engineering, and vector-mediated gene transfer have led to increased interest in bypassing the immune system by expressing neutralizing antibodies directly in muscle.