The London Patient underwent allogeneic stem cell transplantation with d32 homozygous tissue and remission was reported at 18 months. Here we present longer term data including tissue sampling.
Ultra sensitive plasma, semen and CSF viral load assays were used to detect HIV-1 RNA. The method for HIV DNA quantification in gut biopsies and lymph nodes was as follows: tissue samples from each site were mixed with ceramic beads and Qiagen RLT Plus buffer. The tube contents were then homogenised using a MagNA Lyser (Roche) set at 6000rpm for 45 seconds. Genomic DNA was then extracted using a Qiagen AllPrep DNA/RNA Mini Kit. Cell-copy number and total HIV DNA levels were quantified both in triplicate using droplet digital PCR.
HIV-1 viral load in plasma and proviral HIV DNA in CD4 cells have remained below detection up to 30 months. The most recent CD4 count was 370 cells/Ul (20.3%) and CD4/CD8 ratio 0.65. Plasma HIV antibodies have remained undetectable by western blot except low level Env reactivity. Semen viral load was below limit of detection in both plasma (LLD in seminal plasma is <12 copies/ml) and cells (LLD 10 copies/million cells).CSF protein and glucose were normal with no cells detected. HIV-1 viral load in CSF was below detection limit (LLD 1 copy/ml). HIV DNA by ddPCR was negative in Rectum, Caecum, sigmoid and T.Ileum. Lymph node tissue from the axilla was positive for LTR and Env at around 30 copies/million cells, but negative for packaging signal and integrase. The intact proviral DNA assay (IPDA) was negative.
The London patient has been in HIV remission for 2.5 years with no detectable replication competent virus in blood, CSF, intestinal tissue or lymphoid tissue. Donor chimerism has been maintained at 99% in T cells. We conclude that this represents HIV-1 cure with evidence of low level defective HIV genomes in lymphoid tissue.