Assessment of recent HIV-1 infection by a line immunoassay for HIV-1/2 confirmation.

Background: Knowledge of the number of recent HIV infections is important for epidemiologic surveillance. Over the past decade approaches have been developed to estimate this number by testing HIV-seropositive specimens with assays that discriminate the lower concentration and avidity of HIV antibodies in early infection. We have investigated whether this "recency" information can also be gained from an HIV confirmatory assay.

Adaptation of the ultrasensitive HIV-1 p24 antigen assay to dried blood spot testing.

Implementation of molecular tests for the assessment of pediatric HIV-1 infection in resource-limited countries is difficult because of technical complexity and costs. Alternatives like the ultrasensitive HIV-1 p24 antigen enzyme-linked immunosorbent assay have therefore been proposed. We have now adapted this test to dried blood spot (DBS) plasma p24 antigen (p24).

Quantification of HIV-1 p24 by a highly improved ELISA: an alternative to HIV-1 RNA based treatment monitoring in patients from Abidjan, Côte d'Ivoire.

Background: Quantification of HIV-1 RNA remains difficult to implement in Africa. Simple and inexpensive tests for antiretroviral treatment (ART) monitoring are needed.

Objective: To evaluate an HIV-1 p24 ELISA, which combines efficient virus disruption, heat-denaturation and signal amplification, in a West African setting.

Optimized virus disruption improves detection of HIV-1 p24 in particles and uncovers a p24 reactivity in patients with undetectable HIV-1 RNA under long-term HAART.

HIV-1 p24 antigen (p24) measurement by signal amplification-boosted ELISA of heat-denatured plasma is being evaluated as an alternative to HIV-1 RNA quantitation in resource-poor settings. Some observations suggested that virion-associated p24 is suboptimally detected using Triton X-100-based virus dissociation buffer (kit buffer). A new reagent (SNCR buffer) containing both denaturing and non-denaturing detergents was therefore developed and evaluated.

Evaluation of p24-based antiretroviral treatment monitoring in pediatric HIV-1 infection: prediction of the CD4+ T-cell changes between consecutive visits.

Worldwide, 700,000 infants are infected annually by HIV-1, most of them in resource-limited settings. Care for these children requires simple, inexpensive tests. We have evaluated HIV-1 p24 antigen for antiretroviral treatment (ART) monitoring in children.

Ultrasensitive quantitative HIV-1 p24 antigen assay adapted to dried plasma spots to improve treatment monitoring in low-resource settings.

Background: Our group has previously developed a quantitative and ultrasensitive HIV-1 p24 antigen assay that is inexpensive, easy-to-perform, and can be carried out in low-resource settings. Since antiretroviral therapies are becoming more accessible in resource-constrained countries, methods to assess HIV-1 viraemia are urgently needed to achieve a high standard of care in HIV-1 management.

Objectives: To adapt our quantitative assay to dried plasma spots (DPS), in order to further simplify this test and make it more accessible to resource-constrained countries.

HIV-1 p24 may persist during long-term highly active antiretroviral therapy, increases little during short treatment breaks, and its rebound after treatment stop correlates with CD4(+) T cell loss.

The dynamics of HIV-1 RNA during structured treatment interruptions (STIs) are well established, but little is known about viral proteins like p24. We studied 65 participants of an STI trial. Before the trial, continuous highly active antiretroviral therapy (HAART) had suppressed their viral load to <50 copies/mL during 6 months.

HIV-1 p24 antigen is a significant inverse correlate of CD4 T-cell change in patients with suppressed viremia under long-term antiretroviral therapy.

An HIV-1 p24 antigen test involving signal amplification-boosted ELISA of heat-denatured plasma was evaluated prospectively in 55 patients whose viral RNA in plasma had previously been suppressed for at least 6 months under antiretroviral combination therapy. During a median follow-up of 504 days, CD4 counts increased by a median of 62 cells per year. By univariate and multivariate linear regression analysis, the level of p24 antigen as expressed by the absorbance/cutoff ratio was a significant inverse correlate of both the CD4 count in a sample (p =.