Résumé
The human colonic epithelial cell line HT-29 can be productively infected with various HIV-1 and HIV-2 isolates that are highly cytopathic for T lymphocytes. In each case, a chronically infected HT-29 cell line can be established, and progeny viruses retain their original properties including high cytopathogenicity for T cells. Inasmuch as AIDS vaccines should include viral isolates capable of infecting mucosal epithelial cells, it may be useful to produce these isolates in such cells at a large scale. We describe here a microcarrier-based culture system allowing the production of infectious viruses from HT-29 cells grown in a chemically defined serum-free medium (Dulbecco's modified Eagle's medium/F12, HEPES 15 mM, pH 7.4, transferrin$5 \mu g/ml$, selenium 10 ng/ml). The yield of HIV-1 from microcarrier cultures (275 ng of$p24^{gag}/ml$) was greater than the yield from conventional culture flasks (122 ng of$p24^{gag}/ml$). This virus, produced in serum-free medium, can be used either as a viral stock or as a source for HIV-1 proteins.