Retroviral-mediated expression of recombinant Fancc enhances the repopulating ability of Fancc-/- hematopoietic stem cells and decreases the risk of clonal evolution.
Fanconi anemia (FA) is a chromosomal instability disorder characterized by a progressive bone marrow (BM) failure and an increased incidence of myeloid leukemias. Children with FA are currently being enrolled in clinical trials to evaluate the safety of retroviral-mediated gene transfer. Previously, we used Fancc(-/-) mice to show that Fancc(-/-) hematopoietic stem cells (HSCs) have a profound defect in repopulating ability. Here, we examined whether retroviral-mediated gene transfer of recombinant Fancc (rFancc) would restore the repopulating ability of Fancc(-/-) HSC to wild-type levels. Fancc(-/-) HSCs transduced with a retrovirus encoding rFancc exhibited a repopulating ability that approached wild-type levels. Interestingly, approximately 30% of primary recipients (7 of 22) transplanted with uncorrected Fancc(-/-) cells developed a range of hematopoietic abnormalities including pancytopenia and BM hypoplasia similar to individuals with FA. Hematopoietic abnormalities were detected in only 1 of 22 mice transplanted with Fancc(-/-) cells transduced with a retrovirus encoding rFancc. Moreover, several mice with hematopoietic defects had progenitors that displayed a marked resistance to IFN-gamma, TNF-alpha, and MIP-1alpha compared to both Fancc(-/-) progenitors, which are uniquely hypersensitive to these cytokines, and wild-type progenitors. These data are analogous to studies using progenitors from patients with myelodysplasia and provide functional support for clonal evolution in these mice. Collectively, these data show that gene transfer can enhance HSC repopulating ability and suppresses the tendency for clonal evolution. These studies also reveal potential detrimental effects of ex vivo manipulation for untransduced Fancc(-/-) HSCs.
Haneline
Laura S
LS
Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indianapolis, IN, USA. lhanelin@iupui.edu
Li
Xiaxin
X
Ciccone
Samantha L M
SL
Hong
Ping
P
Yang
Yanzhu
Y
Broxmeyer
Hal E
HE
Lee
Suk-Hee
SH
Orazi
Attilio
A
Srour
Edward F
EF
Clapp
D Wade
DW
D000818:Animals; D015153:Blotting, Western; D001853:Bone Marrow / Q000473:pathology; D018797:Cell Cycle Proteins; D002455:Cell Division; D002999:Clone Cells; D004268:DNA-Binding Proteins; D004195:Disease Models, Animal; D005199:Fanconi Anemia; D052218:Fanconi Anemia Complementation Group C Protein; D051856:Fanconi Anemia Complementation Group Proteins; D015870:Gene Expression; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000737:chemistry* / Q000166:cytology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D055728:Primary Myelofibrosis / Q000473:pathology; D011506:Proteins / Q000235:genetics*; D011994:Recombinant Proteins; D012190:Retroviridae / Q000235:genetics*; D033581:Stem Cell Transplantation; D014162:Transfection
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C497652:Fancc protein, mouse; D052218:Fanconi Anemia Complementation Group C Protein; D051856:Fanconi Anemia Complementation Group Proteins; D009687:Nuclear Proteins; D011506:Proteins; D011994:Recombinant Proteins