Interaction Between HSV1 and HIV1 in AIDS Pathogenesis

1
Interaction Between HSV-1 and HIV-1 in AIDS
Pathogenesis

• Arianna Calistri
• University of Padova
• Italy

2
Introduction

• Herpes simplex virus type 1 and 2 (HSV-1 and
  HSV-2) are opportunistic pathogens of major
  importance in the course of AIDS (Nelson et al,
  1990)
• HSV-1 and HSV-2 interact with HIV at the
  molecular and/or cellular level promoting AIDS
  pathogenesis (Griffiths, 1996 1998)
• LTR transactivation (ICP0, ICP27)
• Post-transcriptional transactivation (US11)
• Cytokine release

3
Introduction

• Genital herpes, more than other sexually
  transmitted diseases, appears to be linked to
  HIV-1 transmission
• portal of entry/exit for the virus (Schacker et
  al, 1998)
• HIV-1 load boosting (Dickerson et al, 1996 Mole
  et al, 1997 )
• The prevalence of genital HSV infection has been
  associated with HSV-2, BUT
• An increase in the incidence of HSV-1 infection
  has been observed (Lipsitch et al, 2002)
• In some European cohorts, HSV-1 has been reported
  to be the most common aetiological agent of
  primary genital herpes (Lafferty et al, 2002)

4
Our Aims

• To investigate whether an interaction
  betweenHSV-1 and HIV-1 occurs in CD4
  lymphocytes
• Characterize new molecular interactions between
  HSV-1 and HIV-1 which could be relevant to AIDS
  pathogenesis

5
CEM CD4 T-Cell Line Can Be Persistently
Infected By HSV-1 (CEMHSV cells)
6
HSV-1 Chronic Infection Does Not Affect CD4 And
CXCR4 Expression and Function
CD4
CXCR4
Number of syncytia/field
HIV-1 env expressor plasmid
293T cell transfection
Syncytia formation
Co-culture with CEMHSV or CEM cells
B. Syncytia formation assay
A. Cytofluorimetric analysis
7
HSV-1 Infection of T Lymphocytes Does Not Affect
Intracellular dNTP Pool
8
The Early Phases of HIV-1 Infection Are Not
Affected By HSV-1
rev
CAT
?
tat
vif
SV40
gag
pol
D
env
5LTR
3LTR
vpu
BglI
BglI

rev
env
LTR
LTR
SV40
CAT assay
Recombinant HIV-1 (single round of replication)
of CAT conversion
CEMHSV or CEM
293T cells
9
HIV-1 Superinfection of CEMHSV
10
HSV-1 Replication Induces Apoptosis In CEM Cells
A. FACS Analysis
B. DNA fragmentation analysis
3
2
1
 
Events Events
Events
3
5
3

DNA content
1
70
23
70
23
IF intensity (Ab against HSV-1 glycoproteins)
DNA content
1 CEM 2 CEMHSV 3 CEMHSV ACV
11
HIV-1 Replication is Affected by HSV-1 Related
Apoptosis
RT (cpm/ml x103)
Days p.i.
12
Is the HSV-1 Related Cytopathogenicity a Major
Determinant In HSV/HIV Interactions?
B. HIV-1 LTR transactivation (CEM cells
transfected with pU3RIII)
A. HIV-1 replication (Target cellsCEMHIV)
13
A Cell Line Chronically Infected by Both HIV-1
and HSV-1 (CEMHSV/HIV) Can be Obtained
M 1 2 3 4 5 6
M Molecular marker 1, 4 PCR - control 2, 5
PCR control 3 HSV-specific PCR in
CEMHSV/HIV 6 HIV-specific PCR in CEMHSV/HIV
14
CEMHSV/HIV Produces HIV-1 Particles Pseudotyped
by the HSV-1 Envelope
HSV-1 particle
300
HIV-1 particle
HIV-1 particle pseudotyped by the HSV-1 envelope
CD4 cells
p24 production (ng/ml)
200
CD4- cells
100
M 1 2 3 4 5 6
24 h p.i 48 h p.i
Vero cells cell-free surnatant of CEMHSV/HIV
cells Vero cells surnatant H9 HIV-1
chronically infected cells
M Molecular marker 1 PCR-control 2
PCRcontrol 3 HIV-1 4 HIV-1 pseud by HSV-1
env 5 HIV-1 pseud by HSV-1 env IgG 6 HIV-1
pseud by HSV-1 env AZT
15
Significance of HIV-1 Pseudotyping by HSV-1
Envelope

• A recombinant virion containing the HIV-1 core
  and the HSV envelope could infect a large
  spectrum of CD4- cells
• Spreading of HIV-1 infection to different organs
• High HIV-1 load in the absence of circulating CD4
  cells in terminal phases of AIDS

16
Conclusions

• HSV mediated apoptosis and HIV-1 pseudotyping by
  the HSV envelope take place in lymphocytes
• Both these phenomena could be relevant to AIDS
  progression
• The mechanisms of envelope pseudotyping need to
  be further investigated at the molecular level
• Inhibition of HSV replication could result in a
  clinical benefit for AIDS patients
• Controlled clinical trials

17
Acknowledgments

• Prof. Giorgio Palu
• Prof. Cristina Parolin
• Dr. Luca Benetti
• Dr. Arianna Loregian

Department of Histology, Microbiology and Medical
Biotechnologies
University of Padova, Italy
IHMF Board GlaxoSmithKline