AEGiS-15IAC: An abrogated p24 antigen test to detect plasma infectivity of viraemic HIV patients with and without HAART.

15th International AIDS Conference

Bangkok, Thailand - July 11-16, 2004

An abrogated p24 antigen test to detect plasma infectivity of viraemic HIV patients with and without HAART.

Int Conf AIDS 2004 Jul 11-16; 15:(abstract no. A10345)

Wolf T, Kessel J, Brodt HR, Werner A
Dept. of Infectious diseases, Hospital of the JWG University, Frankfurt, Germany

BACKGROUND: The morbidity and mortality of AIDS has been significantly reduced since the introduction of HAART. Virologic therapy surveillance nowadays consists of regular PCR-based measurement of HIV Viraemia. Little is known however about the plasma infectiousness in various stages of disease and therapy. In HAART-treated but viraemic patients, viral fitness seems to be reduced, probably as a result of secondary mutations. Viral fitness is partially determined by the ability of the virus to infect new target cells. We would like to introduce as an abrogated p24 antigen test that can determine infectiousness from plasma samples of HIV-infected patients in various stages of disease adn therapy.

METHODS: Plasma samples of 17 HIV-infected patients were used in various dilution (1/2-1/10000) to infect PMBC cultures of healthy donors. This assay was repeated 4 times to provide several cycles viral infection. An ELISA was used to determine the presence of p24-antigen in the PBMC culture infected with the different dilutions of plasma, and thus determine a TCID50 infectious dose for each patient sample and each cycle of infection.

RESULTS: The test provided preproducible infectious doses. The TCID50 was not significantly lowered over several cycles of infection. According to preliminary results, TCID50 correlated with HIV-PCR in a significant manner (p<0.05). Whether there is a negative correlation of TCID50 and resistance mutations, or whether TCID50 is lower in viraemic patients under HAART will be clarified in further test (Results expected to be ready for the conference).

CONCLUSIONS: We would like to propose a new test that could serve as a surrogate marker for viral fitness, and thus be useful in furthering the knowledge of viral pathogenicity and dynamics.

Keywords: AEGIS, HIV, Acquired Immunodeficiency Syndrome, HIV Seropositivity, Antiretroviral Therapy, Highly Active, HIV Core Protein p24, HIV Infections, Viremia, Plasma, HIV Antigens, Antigens, HIV Antibodies, Anti-HIV Agents, Polymerase Chain Reaction, Humans, pathogenicity, immunology, virology

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A10345