Deoxyuracil as a marker of replication-competent proviruses

National Institute Of Allergy And Infectious Diseases

Investigators

Abstract

In preliminary studies, we analyzed how a replication-competent resting CD4 T cell reservoir could be established in Fiebig I. Using replication-competent reporter HIV to infect primary resting CD4 T cells, we found that HIV can directly infect resting memory CD4 T cells. These cells: (1) express CCR5, allowing virus entry; (2) produce low levels of dNTPs sufficient for reverse transcription; and (3) possess actively transcribed genes which enable provirus integration. Analysis of the dNTP synthesis pathway in resting infected cells revealed that the enzymes required to convert deoxyuracil (dU) to thymidine (dT) were absent; thus, HIV should incorporate dU into the newly reverse transcribed provirus. We used cells obtained from blood and lymph nodes from treatment-naïve and ART-treated PWH to measure dU and dT content in HIV proviruses within memory CD4 T cells and detected both dU-containing and dT-containing proviruses.