Latent HIV-1 is activated by exosomes from cells infected with either replication-competent or defective HIV-1

Retrovirology

Table 1 HIV-1 latently infecting primary CD4⁺ T lymphocytes is activated upon co-culture with HIV-1 infected autologous lymphocytes in both ADAM17- and Nef-dependent ways

No. of donors assayed	Effector cells in upper chambers	Effector cells: % of CAp24⁺ cells 3 days p.i.	Co-culture conditions	Target cells in lower chambers: % of CAp24⁺ cells after 2 days of co-culture
No. of donors assayed	Effector cells in upper chambers	Effector cells: % of CAp24⁺ cells 3 days p.i.	Co-culture conditions	Mock	ΔenvHIV-1	ΔenvHIV-1 +AZT
5	Ctrl	<0.1	Complete medium	<0.1	<0.1	<0.1
5	wtHIV-1	31.2	Complete medium	<0.1	8.7	<0.1
5	wtHIV-1	32	GW4869+ Spiroepoxide	<0.1	1.6	0.4
3	wtHIV-1	30.9	TAPI-2	0.2	1.8	0.3
2	wtHIV-1	26.4	IgGs	0.2	6.9	0.3
2	wtHIV-1	28.7	Anti-TNFα Abs	0.2	0.2	<0.1
1	ΔnefHIV-1	34.7	Complete medium	0.5	1.8	0.6
1	ΔnefHIV-1	31.3	GW4869+ Spiroepoxide	0.3	0.9	0.3

CD4⁺ T lymphocytes were activated, infected with the indicated VSV-G psedotyped HIV-1 strains and, after 3 days, put in the upper chamber of a trans-well plate in the presence or not of the indicated inhibitors. As a control, activated, uninfected cells (Ctrl) were also assayed. In the third left column, shown are the percentages of HIV-1 expressing cells 3 days after infection as means of duplicates. Infected lymphocyte cultures were then put in separate trans-well co-cultures where in the lower chamber autologous resting CD4⁺ T lymphocytes were seeded 72 h after challenge with Δenv HIV-1 in the absence or presence of AZT. As a control, mock infected cells were also seeded. Percentages of HIV-1 Gag expressing cells were scored after 48 h of co-cultivation in the presence of AZT. Shown are the percentages of HIV-1 expressing cells as detected by intracytoplasmic CAp24 FACS analysis as means of duplicates of independent experiments performed with PBMCs from the number of healthy donors indicated in the first left column

ISSN: 1742-4690