Download HIV-2 PBMCs

Understanding The Role Of SAMHD1 in
HIV1/2 Pathogenesis
Maha Al-Mozaini, Ph.D.
Immunocompromised Host Research
King Faisal Specialist Hospital and Research Centre
Riyadh Saudi Arabia
Riyadh
Saudi Arabia
King Faisal Specialist Hospital and
Research Centre
Acquired Immune Deficiency Syndrome
(AIDS)
Human Immunodeficiency Virus (HIV)
Two major challenges
 HIV vaccine development
 Cure of HIV-1 infection
HIV in Saudi Arabia
Antiretroviral resistance in HIV-infected Saudi children failing first-line highly
active antiretroviral therapy.
Al Hajjar SH1, Frayha H, Althawadi S.
Human immunodeficiency virus type 2 in two Saudi families
Reem S. Almaghrabi, Batool Ali, Sahar Al-Thawadi, Magid Abdel Halim,
Abdulrahman A. Alrajhi
.
HIV-associated nephropathy in Saudi Arabia.
Al-Sheikh H1, Al-Sunaid M, Alrajhi AA.
Isolation of a rare Nocardia wallacei from an HIV-positive patient with
pulmonary infection in Southern Saudi Arabia.
Hamid ME1, Al Azraqi TA, Joseph MR, Al-Hakami AM.
HIV Research
 One of the major barriers to HIV-1 vaccine
development is a lack of understanding of the
correlates of protective immunity against the virus.
 A growing interest of the HIV scientific community is
in studying a minority of HIV-1-infected patients who
control virus replication and remain asymptomatic
without any therapeutic intervention;
HIV-1 Long-term nonprogressors (LTNPs) or Elite Controllers (EC)
HIV-2
Simian Immunodeficiency Virus (SIV)
HIV Genome
HIV-1 Gene Sequence
LTR
Vif
Gag
Pol
Vpr
Vpu
Env
Nef
Vpx
HIV-2/SIV Gene Sequence
LTR
LTR
Vif
Gag
Pol
LTR
Vpr
Vpu
Env
Nef
Ayinde et al. Retrovirology 2010.
Intracellular Transcription Factors
APOBEC3
Tetherin
TRIM
SAMHD1
Sheehy et al., 2002, Neil et al., 2008, Sebastian & Luban, 2005 & Laguette et al, 2011
SAMHD1
Sterile Alpha Motif Domain And Histidine Aspartic Domain Containing Protein 1
Cellular Protein encoded by SAMHD1 gene
Found in myeloid cells and resting CD4 T cells
Phosphohydrolase Activity
Convert nucleotide triphosphate (NTP) to nucleoside
& triphosphate
Deplete the pool of nucleotides available to
a reverse transcriptase for viral cDNA synthesis
Prevent viral replication
RNase Activity
Restrict the HIV-1 infection in Phosphorylation SAMHD1
Without decreasing cellular dNTP levels
Lahouassa et al, 2012 & Ryoo et al, 2014
SAMHD1
St Gelais C & L Wu, 2011.
Aims
 Evaluate the protein interaction of Vpx with SAMHD1 in
transfected cell lines.
 Analyze the protein expression of SAMHD1 in different
HIV infected cells.
 Profile the immune response in different HIV infected
Patients and it relation to Vpx.
HIV Patients
Viral Load
CD4
(copies/ml)
(cells/mm3)
HIV-1
214
200
HIV-2
<50
400
HIV Patients
SAMHD1 and Vpx in Transfected Cells
pcDNA 3.1
pcDNA 3.1 +VPX
72KD
Anti-SAMHD-1
36KD
Anti-GAPDH
14KD
Anti-Vpx
THP-1 cells
THP-1 cells
DAPI
Anti-Vpx
Anti-SAMHD-1
THP-1 cells
DAPI
Anti-Vpx
Anti-SAMHD-1
pcDNA 3.1
Mock
pcDNA 3.1
VPX
SAMHD1 and Vpx in PBMCs Cells
Neg
HIV-1
HIV-2
(A)
HIV-2
(B)
Neg
HIV-1
HIV-2
(A)
HIV-2
(B)
180KD
180KD
Anti-SAMHD-1
Anti-SAMHD-1
72KD
72KD
36KD
Anti-GAPDH
36KD
Anti-GAPDH
14KD
Anti-Vpx
14KD
Anti-Vpx
HIV-2 PBMCs
(Before Treatment)
HIV-2 PBMCs
(On Treatment)
SAMHD1 and Vpx in MDDC Cells
PBMCs
MDDC Cells
Monocyte
Monocyte Derived
Dendritic Cell
(MDDC)
Neg
HIV-1
HIV-2
(A)
HIV-2
(B)
72KD
Anti-SAMHD-1
36KD
Anti-GAPDH
14KD
Anti-Vpx
Transcription level of SAMHD1
Cytokine Analysis
Conclusion
1. Establish a transfected cell line to confirm SAMHD1 and Vpx
interaction.
2. Our results confirmed the true interaction of Vpx and
SAMHD1 using cells from HIV-2 infected patient.
3. The finding of immune modulator SAMHD1 as a restriction
factor in DC opens a new area of investigation in DC-target
vaccination strategies.
4. Preliminary data of cytokines expression in Vpx cell lines was
established.
HIV-2 serves an important
model of natural attenuated
lentivirus infection
Future prospective
• Investigating the possible role of the mutated
gene(s) in Aicardi–Goutieres syndrome in HIV
infection.
• Recent studies suggest that elite controllers
maintain a steady level of HIV-1 replication
without treatment because of overexpression
of p21 & reduced CDK9.
Finding a cure for HIV will require
innovation, collaboration and significant
funding
COLLABORTERS
Abdurahman Al-Rajhi
Eric Rosenberg
Abdullah Al-Hokail
Mathias Lichterfeld
Magid A Mohmed
Michael Mansour
Hail M Al-Abdely
Fahad A Al-Rabiah
Ali Omrani
Xu Yu
Bruce Walker
Nathaniel Landau
Uday Kishore
Acknowledgment
RC Administration
•Dr. Sultan Al-Sedari
Immunocompromised Host
Research Department Of Infection
& Immunity
•Mohammed Al-Ahdal
•Walaa Al-Arnous
•Ibtehaj Al –sharif
•Ahlam Bokh
•Jorge Bautista
•Qais Dirar
•Hanan Sharawi
•Mureen Del Cruz