Patient cured of HIV infection naturally

One patient with HIV-1 may have been cured by naturally achieving a sterilizing cure of the infection, in the absence of a stem cell transplantation, reveals a recent study.

“Genome-intact and replication-competent HIV-1 were not detected in an elite controller despite analysis of massive numbers of cells from blood and tissues,” the investigators said

The study sought to evaluate persistent HIV-1 reservoir cells in an elite controller with undetectable HIV-1 viraemia for more than 8 years in the absence of antiretroviral therapy. A detailed investigation of virologic and immunologic characteristics was conducted at tertiary care centres in Argentina and the US involving a patient with HIV-1 infection and durable drug-free suppression of HIV-1 replication.

The investigators performed an analysis of genome-intact and replication-competent HIV-1 using near-full-length individual proviral sequencing and viral outgrowth assays, respectively. They also analysed HIV-1 plasma RNA using ultrasensitive viral load testing.

As a result, no genome-intact HIV-1 proviruses were detected in an analysis of 1.188 billion peripheral blood mononuclear cells and 503 million mononuclear cells from placental tissues. Seven defective proviruses were found, of which some were obtained from clonally expanded cells.

Furthermore, a viral outgrowth assay did not retrieve replication-competent HIV-1 from 150 million resting CD4⁺ T cells. HIV-1 RNA was not detected in 4.5 mL of plasma.

“These observations raise the possibility that a sterilizing cure may be an extremely rare but possible outcome of HIV-1 infection,” the investigators said.

The study, however, was limited by the fact that the absence of evidence for intact HIV-1 proviruses in large number of cells does not mean the absence of HIV-1 proviruses as well, and that a sterilizing cure of HIV-1 cannot be proven empirically.

Recently, “a sterilizing cure of HIV-1 infection has been reported in two persons living with HIV-1 who underwent allogeneic hematopoietic stem cell transplantations from donors who were homozygous for the CCR5Δ32 gene polymorphism. However, this has been considered elusive during natural infection,” the investigators noted.