Previous Article | Next Article ![]()
Clinical and Diagnostic Laboratory Immunology, September 2005, p. 1117-1118, Vol. 12, No. 9
1071-412X/05/$08.00+0 doi:10.1128/CDLI.12.9.1117-1118.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.
Departments of Clinical Virology,1 Clinical Biochemistry,2 Internal Medicine (Unit 1), Christian Medical College, Vellore, Tamil Nadu, India 6320043
Received 30 May 2005/ Returned for modification 10 June 2005/ Accepted 16 June 2005
| ABSTRACT |
|---|
|
|
|---|
| TEXT |
|---|
|
|
|---|
Blood samples were collected from 30 treatment-naïve HIV-infected individuals (24 men and 6 women; median age, 33 years; range, 22 to 55 years) and 30 normal healthy age- and sex-matched individuals (24 men and 6 women; median age, 35 years; range, 22 to 58) after obtaining informed consent. Blood samples were drawn between 8 and 10 a.m. on the days of sampling. None of the HIV-infected or the normal healthy individuals had Cushing's syndrome or Addison's disease. The HIV-1 viral load and CD4+ and CD8+ T-cell estimations were done for all the HIV-infected individuals using standard methods.
A commercially available radioimmunoassay (Diagnostic Products Corporation) was used to measure DHEAS concentration. The assay was carried out as per the manufacturer's instructions. Briefly, in polypropylene tubes coated with antibodies to DHEAS, ligands in the patient samples compete with 125I-labeled DHEAS. After incubation and separation of the bound from the free form, the tubes were read in a gamma counter (Wallac; GMI, Inc., Minnesota). The counts were inversely related to the amount of DHEAS in the sample. A calibration curve was then used to quantify the DHEAS in the sample. Viral loads were determined using Amplicor HIV-1 Monitor test v1.5. The CD4+ T-cell counts were measured by flow cytometry for 14 individuals (Becton Dickinson, San Jose, CA) and by the Capcellia assay (Bio-Rad, Paris, France) for the remaining 16 samples. For the correlation analysis between DHEAS and CD4 cell counts, only those 14 patients whose CD4 cell counts were measured by flow cytometry were used.
Among the 30 HIV-infected individuals, 16 were asymptomatic, and 13 were symptomatic (one of the individuals' clinical status was not known). The asymptomatic HIV-1-infected individuals had an HIV-1 RNA copy number of 5.2 log10, while the symptomatic individuals had an RNA copy number of 5.5 log10. The mean DHEAS level ± standard deviation in the normal healthy individuals was 207 ± 123 µg/dl (median, 170 µg/dl), and in HIV-infected individuals it was 68 ± 47 µg/dl (median, 61 µg/dl). The mean DHEAS level ± standard deviation among the asymptomatic individuals was 83.5 ± 52 µg/dl (median, 79 µg/dl), and that in the symptomatic individuals was 53 ± 33 µg/dl (median, 46 µg/dl). The difference between the levels of healthy individuals and those of HIV-infected individuals was significant (P < 0.001; Kruskal-Wallis H). The data are shown in Fig. 1. The difference in DHEAS levels between asymptomatic and symptomatic HIV-1-infected individuals was not significant (P = 0.1; Kruskal-Wallis H). There was a trend towards positive correlation between levels of DHEAS and those of CD4+ T cells, with an r value of 0.28, though it was not significant (P > 0.05; regression analysis, F = 1.01).
|
Studies have shown low DHEAS levels to be of negative prognostic value during the course of HIV infection (5). Moreover, it has also been shown that the initiation of antiretroviral therapy can induce an increase in circulating DHEAS (5). The increased DHEAS level may be directly inhibitory to HIV viral replication, as it has been shown that DHEA protects against acute lethal viral infection and can inhibit the HIV-1 latency reactivation (6). There are some recent reports on lower DHEAS levels in HIV- and hepatitis C virus-coinfected patients than in HIV-monoinfected individuals (7). Schifitto et al. have shown that in HIV-1-infected individuals with low plasma levels of DHEAS, there is a trend towards a TH2 cytokine profile (10).
Previous studies have been done in areas where subtype B is predominant. The present study was conducted in an area where subtype C is the predominant strain (9). It is now recognized that subtype C will be the globally predominant HIV-1 type (8). From our study, it appears that the changes in DHEAS levels are more a consequence of immune/endocrine function decline and that they are unrelated to the infecting virus subtype. Further studies are required to explore the use of plasma DHEAS levels with CD4+ T-cell estimation (U.S. $14) for monitoring HIV patients, especially those on therapy. The DHEAS assay (U.S. $9) is 1/10 the cost of viral load estimation (U.S. $89) and may be a useful surrogate marker for economical management of patients. Presently, commercial enzyme-linked immunosorbent assay reagents have become available, making DHEAS measurements possible in laboratories attached to secondary-level hospitals. Most secondary-level hospitals in countries like India currently have facilities for enzyme-linked immunosorbent assay to screen for blood-borne viruses. This also obviates the need for expensive equipment for radioimmunoassay applications. In countries like India, physicians prescribing antiretroviral therapy find three monthly viral load measurements more expensive than therapy for a year. The argument in favor of using DHEAS measurement for monitoring successful antiretroviral therapy is its low cost. Further cohort-based studies need to be undertaken.
| FOOTNOTES |
|---|
| REFERENCES |
|---|
|
|
|---|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Antimicrob. Agents Chemother. | Clin. Microbiol. Rev. | Infect. Immun. |
|---|---|---|
| J. Clin. Microbiol. | J. Virol. | ALL ASM JOURNALS |