Previous studies support dasatinib as a potent inhibitor of HIV-1 replication. However, a functional distinction between 2 kinase targets of the drug, ABL1 and ARG, has not been assessed.
We used primary CD4+ T‐cells, CD8-depleted peripheral blood mononuclear cells (PBMCs) from a treatment naïve HIV-1+ patient, and a humanized mouse model of HIV-1 infection. We assessed the roles of ABL1 and ARG during HIV-1 infection and use of dasatinib as a potential antiviral against HIV-1 in humanized mice.
Primary CD4+ T‐cells were administered siRNA targeting ABL1 or ARG, then infected with HIV-1 containing luciferase reporter viruses. Quantitative polymerase chain reaction of viral integration of 4 HIV-1 strains was also assessed. CD8-depleted PBMCs were treated for 3 weeks with dasatinib. NSG mice were engrafted with CD34+ pluripotent stem cells from human fetal cord blood, and infected with Ba-L virus after 19 weeks. Mice were treated daily with dasatinib starting 5 weeks after infection.
siRNA knockdown of ABL1 or ARG had no effect on viral reverse transcripts, but increased 2-LTR circles 2- to 4-fold and reduced viral integration 2- to 12-fold. siRNA knockdown of ARG increased SAMHD1 activation, whereas knockdown of either kinase reduced RNA polymerase II activation. Treating CD8-depleted PBMCs from a treatment-naïve patient with 50 nM of dasatinib for 3 weeks reduced p24 levels by 99.8%. Ba-L (R5)-infected mice injected daily with dasatinib showed a 95.1% reduction in plasma viral load after 2 weeks of treatment.
We demonstrate a novel nuclear role for ABL1 and ARG in ex vivo infection experiments, and proof-of-principle use of dasatinib in a humanized mouse model of HIV-1 infection.
aDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada;
bCurrently, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada;
cDepartment of Medicine, University of Toronto, Toronto, Ontario, Canada;
dCentre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada;
eCurrently, Faculté des Sciences, École Supérieure de Biologie-Biochimie- Biotechnologies, Lyon, France;
fCurrently, Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada;
gDepartment of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada; and
hDivision of Experimental Therapeutics, Toronto General Hospital Research Institute, Toronto, Ontario, Canada.
Correspondence to: Donald R. Branch, PhD, Centre for Innovation, Canadian Blood Services, Room 342, 67 College Street, Toronto, ON M5G 2M1, Canada (e-mail: email@example.com) or Raymond W. Wong, PhD, Department of Medicine, University of Toronto, 67 College Street, Toronto, ON M5G 2M1, Canada (e‐mail: firstname.lastname@example.org).
Supported by the Canadian Foundation for AIDS Research (CANFAR), the Ontario HIV Treatment Network (OHTN), the Canadian Institutes of Health Research (CIHR) Operating Grant–Priority Announcement (PA): HIV/AIDS Research Initiative (HOP-134065) to A.C., the CIHR Fellowship–PA: HIV/AIDS Research Initiative (158250) to R.W.W., the CIHR Doctoral Award–Frederick Banting and Charles Best Canada Graduate Scholarship to R.W.W. Support was partially provided by Canadian Blood Services Graduate Fellowship Program (GFP) Award to S.D.S.M. Additional support was provided by the Centre for Innovation of the Canadian Blood Services using general resources provided in part by Health Canada, a department of the federal government of Canada, to D.R.B. The views expressed herein do not necessarily represent the view of the federal government of Canada.
Presented at the 25th Annual Canadian Conference on HIV/AIDS Research (CAHR 2016); May 12–15, 2016; Winnipeg, MA.
The authors have no conflicts of interest to disclose.
D.R.B. developed the research studies, while D.R.B., S.D.S.M., D.L. and R.W.W. designed experiments, analyzed the data and wrote the paper; S.D.S.M., D.L, P.N, R.W.W., H.N.K. and B.B. performed the research; M.O. and A.C. provided materials for the studies. S.D.S.M. and R.W.W. contributed equally to the study. All authors discussed the results and commented on the manuscript.
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Received November 19, 2018
Accepted July 10, 2019