Genome-wide analysis identifies novel loci influencing plasma apolipoprotein E concentration and Alzheimer's disease risk.

The APOE 2/3/4 polymorphism is the greatest genetic risk factor for Alzheimer's disease (AD). This polymorphism is also associated with variation in plasma ApoE level; while APOE*4 lowers, APOE*2 increases ApoE level. Lower plasma ApoE level has also been suggested to be a risk factor for incident dementia.

Early Antiretroviral Therapy in South African Children Reduces HIV-1-Infected Cells and Cell-Associated HIV-1 RNA in Blood Mononuclear Cells.

We measured cell-associated human immunodeficiency virus (HIV)-1 DNA (CAD) and RNA (CAR) and plasma HIV-1 RNA in blood samples from 20 children in the Children with HIV Early Antiretroviral (CHER) cohort after 7-8 years of suppressive combination antiretroviral therapy (cART). Children who initiated cART early (<2 months; n = 12) had lower HIV-1 CAD (median, 48 vs 216; P < .01) and CAR (median, 5 vs 436; P < .

Improved single-copy assays for quantification of persistent HIV-1 viremia in patients on suppressive antiretroviral therapy.

A quantitative real-time PCR (qRT-PCR) assay with single-copy sensitivity targeting HIV-1 gag RNA (the gag single-copy assay [gSCA]) has been used widely to quantify plasma viremia below the limit of detection of clinical assays in patients on effective antiretroviral therapy (ART), but viral RNA in 15 to 30% of samples amplifies inefficiently because of primer/probe mismatches. We sought to develop improved single-copy assays with increased sensitivity by improving nucleic acid recovery, designing qRT-PCR primers and a probe for a highly conserved region of integrase in the HIV-1 pol gene (the integrase single-copy assay [iSCA]), and increasing the plasma volume tested (Mega-iSCA). We evaluated gSCA versus iSCA in paired plasma samples from 10 consecutive patients with viremia of >1,000 copies/ml and 25 consecutive patients on suppressive ART.

HIV-1 DNA decay dynamics in blood during more than a decade of suppressive antiretroviral therapy.

Background: Human immunodeficiency virus type 1 (HIV-1) DNA dynamics during long-term antiretroviral therapy (ART) are not defined.

Methods: Blood mononuclear cells obtained during 7-12 years of effective ART were assayed for total HIV-1 DNA and 2-long terminal repeat (LTR) circles by quantitative polymerase chain reaction (qPCR). Slopes of HIV-1 DNA were estimated by participant-specific linear regressions.

Residual plasma viraemia and infectious HIV-1 recovery from resting memory CD4 cells in patients on antiretroviral therapy: results from ACTG A5173.

Background: In HIV-1-infected patients receiving antiretroviral therapy (ART), the relationship between residual viraemia and ex vivo recovery of infectious virus from latently infected CD4 cells is uncertain.

Methods: We measured residual viraemia (HIV-1 RNA copies/ml) by single-copy assay (SCA) and the latent reservoir by infectious virus recovery from resting memory CD4 cells (infectious units per million cells [IUPM]) in patients who initiated ART. We assessed immune activation by measuring CD38 expression on T-cells.

New tools for quantifying HIV-1 reservoirs: plasma RNA single copy assays and beyond.

Quantification of plasma HIV-1 RNA below the limit of FDA-approved assays by a single copy quantitative PCR assays (SCA) has provided significant insights into HIV-1 persistence despite potent antiretroviral therapy as well as a means to assess the impact of therapeutic strategies, such as treatment intensification, on residual viremia. In this review, we discuss insights gained from plasma HIV-1 RNA SCA and highlight the need for additional assays to characterize better the cellular and tissue reservoirs of HIV-1. Accurate, reproducible, and sensitive assays to quantify HIV-1 reservoirs, before and after therapeutic interventions, are essential tools in the quest for a cure of HIV-1 infection.