Table 2.
Genetic Typing and Tests of HIV-1 Persistence
| Case 1 | Case 2 | Case 3a | Case 4a | |
|---|---|---|---|---|
| Age/Sex | 7 y/F | 7 y/F | 2.5 y/F | 2.5 y/M |
| HLA typing | A*01 – A*02; B*27 – B*58; C*02 – C*03 |
A*30 – A*66; B*44 – B*45; C*03 – C*04 |
A*01 – A*66; B*55 – B*58; C*03 – C*03 |
A*01 – A*66; B*55 – B*58; C*03 – C*03 |
| HLA-B variationb | 67CM; 70 K/S; 97R/T | 67S; 70N; 97R | 67Y/M; 70Q/S; 97R/T | 67Y/M; 70Q/S; 97R/T |
| CCR-5 Δ32 status | Wild type | Wild type | Wild type | Wild type |
| Mean CD4+ T-cell count (% past year) | 1432 cells/µL (51.1%) | 1371 cells/µL (38.8%) | 1268 cells/µL (46.3%) | 1263 cells/µL (44.5%) |
| Serology | ||||
| ELISA | Negative | Negative | Negative | Negative |
| Western blot | Negative | Negative | Negative | Negative |
| T-cell responses | ||||
| HIV-1 Gag | Undetectable | Undetectable | Undetectable | Undetectable |
| HIV-1 Nef | Undetectable | Undetectable | Undetectable | Undetectable |
| Plasma viremiac | <1.5 copies/mL | <1.5 copies/mL | <1.5 copies/mL | <1.5 copies/mL |
| Cell-associated DNA | <2.6 copies/106 CD4+ T cells | <2.6 copies/106 CD4+ T cells | <2.6 copies/106 CD4+ T cells | <2.6 copies/106 CD4+ T cells |
| Cell-associated RNAd | 24.9 copies/1.5 µg RNA | 20.0 copies/1.5 µg RNA | 19.5 copies/1.5 µg RNA | 130 copies/1.5 µg RNA |
| RNA in stimulated CD4+ T-cell culturee | Not detected (5.4 M) | Not detected (7.2 M) | Not detected (8.0 M) | Not detected (8.0 M) |
| Quantitative CD4+ T-cell co-culturef | Not detected | 0.1 IU/106 CD4+ T cells | Not done | Not done |
Abbreviations: ELISA, enzyme-linked immunosorbent assay; HIV-1, human immunodeficiency virus type 1; HLA, human leukocyte antigen; IU, infectious units; M, million.
a Nonidentical twins; contamination from one twin to the other was not possible as their blood draws were performed on different days and HLA typing was performed on different days with dozens of other individuals samples tested in between.
b HLA-B variation at positions associated with better virologic control (lower set-point); specific amino acid substitutions are indicated in bold.
c Limit of detection: 1.5 copies/mL; each assay performed on 6 mL of whole blood.
d Limit of detection: 1.5 µg RNA; performed in duplicate.
e Limit of detection: 20 copies/mL; M denotes millions of cells.
f Measured as infectious unit per million CD4+ T cells; performed in replicates of 10.