Antisense to transforming growth factor-beta(1) facilitates the apoptosis of macrophages in rat vein grafts.
BACKGROUND
The success of peripheral vein grafts is limited by intimal hyperplasia. Transforming growth factor (TGF)-beta(1) has effects on cell proliferation, apoptosis and extracellular matrix synthesis. We have previously observed positive changes in vessel healing with antisense to TGF-beta(1).


METHODS
Adenovirus was used to transduce rat femoral artery vein grafts with antisense to TGF-beta(1) (Ad-AST) or the sequence encoding the bioactive form of TGF-beta(1) (Ad-BAT). Grafts were harvested at 1, 2, 4 and 12 weeks and formalin fixed for immunohistochemical studies of the cell markers proliferating cellular nuclear antigen (proliferation) and active caspase 3 (apoptosis). In situ DNA fragmentation assays were also performed to confirm active caspase 3 results.


RESULTS
Ad-AST treatment significantly (p = 0.05) increased apoptosis of macrophages inside the internal elastic lamina. In addition, Ad-AST treatment significantly increased the cellularity of the graft at early time points and reduced it at later time points (p = 0.01).


CONCLUSIONS
The low levels of TGF-beta(1) in Ad-AST treatment promote apoptosis of macrophages and provide an environment that is more conducive to the proliferation or infiltration of cells that contribute to healthy vessels.
Heaton
Nicholas S
NS
W.S. Middleton VA Hospital and the University of Wisconsin School of Medicine and Public Health, Madison, Wisc., USA.
Wolff
Randal A
RA
Malinowski
Rita L
RL
Hullett
Debra A
DA
Hoch
John R
JR
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation; D053938:DNA Fragmentation; D004789:Enzyme Activation; D005263:Femoral Artery / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006083:Graft Occlusion, Vascular / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D006965:Hyperplasia; D007150:Immunohistochemistry; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology; D008297:Male; D016376:Oligonucleotides, Antisense / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors; D014161:Transduction, Genetic; D053773:Transforming Growth Factor beta1 / Q000235:genetics / Q000378:metabolism*; D014680:Veins / Q000378:metabolism* / Q000473:pathology / Q000637:transplantation
D016376:Oligonucleotides, Antisense; D018809:Proliferating Cell Nuclear Antigen; D053773:Transforming Growth Factor beta1; C505410:Casp3 protein, rat; D053148:Caspase 3