HIV-1 virion accumulation and ATP-induced release in human
primary monocyte-derived macrophages
AIDS Immunopathogenesis UnitVita-Salute San Raffaele University, Milan, Italy
Francesca GrazianoPhD Student
Poster n°WEPDA0103
Macrophage
Virion synthesis & accumulation
CD4+ T cell
Cell Death
What is the nature of HIV-containing vacuoles?
What else is contained in addition to HIV virions?
ATPP2X7
Receptor
Permeabilized
plasma membrane
Pyroptotic/NecroticPathway
Exosome Pathway
Microvesicles Pathway
Autophagic Pathway
HIV-1
Hypothesis:Are the intracellular HIV-1 virions released by extracellular ATP stimulation, like IL-1b?
IL-1 β ?
The IL-1b Release Pathway. A potential model for HIV-1 infection of Mø?
MODEL (I): Chronically infected promonocytic cell line U1 (2 copies of integrated virus/cell).
N=8
* *** ***oxATP
ATP
HIV-1
1 min. 5 min. 10 min.
Untreated
oxATP
ATP
N=3
**
IL-1b
N=8
uPA prevents virion release from PMA stimulated U1 cells
uPA: urokinase-type Plasminogen Activator
ATP induces a release pathway in stimulated U1 cells
Alternatively Activated M2-MDM
Classically Activated M1-MDM
IL-4IFN-MDM
N=18
MODEL (II)HIV-1 Infection of primary monocyte-derived macrophages (MDM)
N=25MDM
10’ 20’ 30’
M1-MDM M2-MDM
10’ 20’ 30’ 10’ 20’ 30’
Untreated
ATP
ATP induces the release of HIV virions from HIV-1 infected MDM
p24
UN 1 mM ATP
FSC
MDMUN 1 mM ATP
M2-MDM
ATP reduces the intracellular amount
of HIV-1 virions16,7 9,63 20,2 6,78
1 representative of 7
Conclusions
HIV-1 virions accumulate in intracellular vacuoles in differentiated U1 cells and primary MDM.
ATP promotes the release of IL-1b and HIV-1 virions in both cell types.
These results suggest that HIV-1 exploits the microvesicle pathway to be released from infected macrophages.
Acknowledgements
AIDS Immunopathogenesis Unit
Guido Poli
Massimo Alfano
Elisa Vicenzi
INSPE Division of Neuroscience
Roberto Furlan
Livia Garzetti
Humanitas Clinical and Research Center
Massimo Locati
Poster N° WEPDA0103