Ondoa P, Kestens L, Davis D, Fransen K, Vingerhoest J, Marissens D, Heeney J, van der Groen G; International Conference on AIDS.
Int Conf AIDS. 2000 Jul 9-14; 13: abstract no. WePpA1292.
P. Ondoa, Institute of Tropicale medicine-Antwerp, 155, Nationale Straat, 2000B Antwerp, Belgium, Tel.: +32 3 247 63 20, Fax: +32 3 247 63 33, E-mail: Pondoa@itg.be
Background: To gain more insights into the mechanism of resistance to AIDS of SIVcpz infected chimpanzees, we have studied longitudinally plasma and cell IVT, VL and in vitro CD8+T cells suppressive activity on virus replication in NI and EI. Beta-chemokine secretion and cellular expression of CCR5 by CD4+T cells in virus suppression in vitro were also examined. Method: Virus isolation, titration and in vitro suppression of virus replication were analyzed every 3 months using fresh blood. VL was measured retrospectively on cryopreserved samples with an in-house technique. In vitro virus suppression was evaluated by viral antigen release by PHA-stimulated PBMC, purified CD4+T and CD4/CD8+T. RANTES, MIP1-alpha/beta concentrations in culture supernates were determined by ELISA. Cellular CCR5 expression was evaluated by flow cytometry. Results: NI and EI were followed-up for 11 and 4 years respectively. In NI, the first 8 years of IVT fluctuation in plasma and PBMC was accompanied by fluctuation in virus suppression. Then, onset of low or undetectable levels of plasma and cell IVT corresponded to a period of successful SIVcpz suppression in vitro. In EI, an early decrease of IVT at 1,5 year of post infection corresponded to constant virus suppression. Overall, no significant correlation between low plasma and cell IVT and in vitro virus suppression was observed. In contrast to HIV-1 infected human long-term nonprogressors, VL remained stable and high over time in the 2 animals and did not correlate with plasma and PBMC infectious viremia. We found no evidence for the involvement of high level of Beta-chemokine secretion and low expression of CCR5 on in vitro virus suppression. Conclusion: These findings suggest that resistance to AIDS of SIVcpz-infected chimpanzees is not related to low plasma VL. It remains unclear whether CD8+T-mediated virus suppression plays a role in the maintenance low IVT and asymptomatic clinical condition in NI and EI.
Publication Types:
Keywords:
- Animals
- Antigens, CD4
- Antigens, CD8
- Chemokine CCL5
- Chemokines, CC
- HIV Infections
- HIV-1
- Humans
- In Vitro
- Pan troglodytes
- RNA, Viral
- Receptors, CCR5
- Simian Acquired Immunodeficiency Syndrome
- Simian immunodeficiency virus
- Viral Load
- Virus Diseases
- Virus Replication
- Viruses
- immunology
- organization & administration
- virology
Other ID:
UI: 102240122
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