? This proposal will develop foamy virus (FV) vectors for the treatment of leukocyte adhesion deficiency (LAD). In LAD, mutations in the CD18 gene prevent the migration of white blood cells (leukocytes) into tissues, resulting in life-threatening bacterial infections. Transplantation of autologous hematopoietic stem cells (HSCs) transduced by CD18-expressing vectors could cure this disease. However, human and large animal HSCs are difficult to transduce efficiently, and integrating vectors based on murine leukemia virus (MLV) have been shown to cause leukemia by activating nearby cellular proto-oncogenes. FVs are retroviruses and vectors based on them are able to efficiently deliver genes to HSCs. They are not pathogenic so FV vectors may be safer than other types of retroviral vectors. Here FV vectors will be used to deliver the canine CD18 gene to the HSCs of dogs with canine LAD (CLAD). These HSCs will then be transplanted into CLAD dogs, where they will differentiate into mature blood cells that express CD18. If adequate CD18 levels are obtained, the transplanted dogs should improve clinically and avoid an early death due to infections. The data will be used to determine the efficiency of transferring genes into canine HSCs with FV vectors. Integration site analysis will establish how many different transduced cell clones contributed to blood formation, and whether there was selective expansion of particular clones. The transplanted animals will be followed long-term to look for potential side effects, including the development of leukemia. Different conditioning regimens used to promote engraftment of transplanted cells will be tested. FV vectors that use different promoters will be evaluated. FV vectors will be compared to similar lentiviral vectors that express CD18 to determine the best type of vector for HSC gene therapy of LAD. These experiments will determine if FV vectors can efficiently transfer genes to canine bone marrow stem cells, and if FV vectors expressing CD 18 can cure CLAD. This could lead to the development of new treatments for LAD, as well as other genetic or acquired blood diseases, which could improve the health of many Americans. If shown to be safe and effective, the FV vectors tested in the proposed experiments could then be used in human clinical trials to treat LAD. ? ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL085107-03
Application #
7467903
Study Section
Special Emphasis Panel (ZRG1-GTIE-A (01))
Program Officer
Thomas, John
Project Start
2006-08-01
Project End
2010-06-30
Budget Start
2008-07-01
Budget End
2009-06-30
Support Year
3
Fiscal Year
2008
Total Cost
$364,161
Indirect Cost
Name
University of Washington
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Goodman, Michael Aaron; Arumugam, Paritha; Pillis, Devin Marie et al. (2018) Foamy Virus Vector Carries a Strong Insulator in Its Long Terminal Repeat Which Reduces Its Genotoxic Potential. J Virol 92:
Nasimuzzaman, Md; Lynn, Danielle; Ernst, Rebecca et al. (2016) Production and purification of high-titer foamy virus vector for the treatment of leukocyte adhesion deficiency. Mol Ther Methods Clin Dev 3:16004
Bauer Jr, Thomas R; Tuschong, Laura M; Calvo, Katherine R et al. (2013) Long-term follow-up of foamy viral vector-mediated gene therapy for canine leukocyte adhesion deficiency. Mol Ther 21:964-72
Deyle, D R; Khan, I F; Ren, G et al. (2013) Lack of genotoxicity due to foamy virus vector integration in human iPSCs. Gene Ther 20:868-73
Bauer Jr, T R; Olson, E M; Huo, Y et al. (2011) Treatment of canine leukocyte adhesion deficiency by foamy virus vectors expressing CD18 from a PGK promoter. Gene Ther 18:553-9
Ohmine, Ken; Li, Yi; Bauer Jr, Thomas R et al. (2011) Tracking of specific integrant clones in dogs treated with foamy virus vectors. Hum Gene Ther 22:217-24
Josephson, Neil C; Russell, David W (2010) Production of foamy virus vector and transduction of hematopoietic cells. Cold Spring Harb Protoc 2010:pdb.prot5481
Andrianaki, A; Siapati, E K; Hirata, R K et al. (2010) Dual transgene expression by foamy virus vectors carrying an endogenous bidirectional promoter. Gene Ther 17:380-8
Trobridge, Grant D; Allen, James; Peterson, Laura et al. (2009) Foamy and lentiviral vectors transduce canine long-term repopulating cells at similar efficiency. Hum Gene Ther 20:519-23
Taylor, Jason A; Vojtech, Lucia; Bahner, Ingrid et al. (2008) Foamy virus vectors expressing anti-HIV transgenes efficiently block HIV-1 replication. Mol Ther 16:46-51