Table 1.
Characteristics of study participants
| Characteristic | HIV-1-positive plasma (n = 20) | HIV-2-positive plasma (n = 20) | HIV-1/2-positive plasma (n = 11) | P valuea |
|---|---|---|---|---|
| Median (IQRb) age (yr) | 35.1 (29.3–49.0) | 61.6 (54.8–68.0) | 47.0 (33.1–55.6) | <0.001 |
| Gender (% women) | 75 | 70 | 73 | 0.939 |
| HTLV status (% positive) | 25 | 45 | 0 | 0.026 |
| % with viral load (no. of RNA copies/ml) ofc: | ||||
| <1,001 | 22 | 72 | 14 | |
| 1,001–10,000 | 22 | 22 | 14 | |
| >10,000 | 56 (data missing for 2) | 6 (data missing for 2) | 72 (data missing for 4) | 0.003 |
| Median (IQR) CD4+ T cell count/μld | 227 (176–341) | 422 (261–500) | 376 (69–489) | 0.198 |
| % with CD4+ T cell count/μld of: | ||||
| >499 | 16 | 28 | 20 | |
| 200–499 | 53 | 67 | 50 | |
| <200 | 31 (data missing for 1) | 5 (data missing for 2) | 30 (data missing for 1) | 0.346 |
| Median (IQR) total IgG level ( mg/dl)e | 22.6 (15.3–25.7) (data missing for 4) | 13.0 (10.3–15.6) (data missing for 2) | 17.8 (10.8–27.1) (data missing for 5) | 0.041 |
P values calculated using the Kruskal-Wallis test, comparing means over the columns, the chi-square test, or Fisher's exact test when appropriate.
IQR, interquartile range.
The plasma HIV-1 and HIV-2 loads were analyzed by measuring RT activity using the Cavidi ExaVir Load kit (Cavidi Tech AB, Uppsala, Sweden) according to the manufacturer's instructions. Both HIV-1 and HIV-2 were detected with this method, and results are presented as number of RNA copy equivalents/ml.
The percentage and absolute CD4+ T cell counts were determined either by flow cytometry on a FACStrak instrument (Becton Dickinson, San Jose, CA) using three two-color immunofluorescence reagents (CD45/CD14, CD3/CD4, and CD3/CD8; Simultest; Becton Dickinson, San Jose, CA) in combination with leukocyte counts or by flow cytometry on a CyFlow instrument (Partec GmbH, Münster, Germany) using a CD4% antibody kit (CyTecs GmbH, Görlitz, Germany) according to the manufacturer's instructions.
IgG levels were measured by an in-house ELISA (47) with reagents from Jackson Immunotech (Marseille, France). In brief, plates were coated overnight with AffiniPure goat anti-human IgG (20 μg/ml), alkaline phosphatase-conjugated anti-human IgG (diluted to 1:5,000) was used as a detection antibody, and purified human IgG was used as a standard.