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Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
Seronegative HIV-2 carriers in India
S Kageyama1, J K Maniar, M Iwasaki
1Department of Virology, Toyama Medical and Pharmaceutical University, Japan.
International Journal of STD & AIDS
|February 10, 2000
Summary
Seronegative individuals in Mumbai were found to be infected with human immunodeficiency virus type 2 (HIV-2). Despite negative antibody tests, HIV-2 RNA and DNA were detected, suggesting low viral replication causes undetectable antibody levels.
Area of Science:
- Virology
- Immunology
- Infectious Diseases
Background:
- Discordant cases of human immunodeficiency virus type 2 (HIV-2) infection, where individuals test seronegative despite evidence of infection, have been identified.
- Understanding the mechanisms behind seronegativity in HIV-2 carriers is crucial for accurate diagnosis and disease management.
Purpose of the Study:
- To investigate the characteristics of seronegative HIV-2 cases identified in Mumbai, India.
- To determine the viral load and antibody response in these discordant cases.
Main Methods:
- Isolation of HIV-2 RNA and DNA from patient samples.
- HIV-2 cDNA sequence determination.
- Antigen detection assays.
- Antibody reactivity testing against the isolated HIV-2 strain.
Main Results:
- HIV-2 was successfully isolated from culture medium, with detectable HIV-2 RNA and proviral DNA.
- Sequencing revealed no significant alterations in the isolated HIV-2 genomic RNA that would affect antibody binding.
- Antibodies from the same individuals did not react with the isolated HIV-2 strain's antigen, even after 8 months.
Conclusions:
- Extremely low or absent antibody production in these HIV-2 carriers may result from suboptimal immune stimulation due to very slow viral replication.
- A low HIV-2 viral load is likely responsible for the negative antibody test results in these identified carriers.
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