Granulocyte-macrophage colony-stimulating factor gene based therapy for acute limb ischemia in a mouse model.
BACKGROUND
Granulocyte-colony-stimulating factor (GM-CSF) is a pleiotropic factor for hematopoiesis that stimulates myeloblasts, monoblasts and mobilization of bone marrow stem cells. Therefore, the GM-CSF gene is a potential candidate for vessel formation and tissue remodeling in the treatment of ischemic diseases.


METHODS
A new mouse limb ischemia was established by surgery and gene transfer was performed by injection of 100 microg of a plasmid carrying GM-CSF. Muscle force and weight, histology, capillary density, circulating stem cells and monocytes were determined after 3-4 weeks.


RESULTS
More than 60% of nontreated ischemic animals showed gangrene below the heel after 4 weeks, whereas the GM-CSF gene-treated animals showed only darkening of nails or toes. These animals demonstrated a full recovery of the affected muscles in terms of weight, force and muscle fiber structure, but the muscles of nontreated ischemic animals lost approximately 50% weight, 86% force and their regular structure. When the GM-CSF gene was injected into the contralateral limb, only partial loss was observed, demonstrating a distant effect of GM-CSF. The capillary density in the GM-CSF-treated group was 52% higher in relation to the nontreated group. Blood analysis by flow cytometry showed that the GM-CSF-treated group had 10-20% higher levels of circulating monocytes and Sca-1(+).


CONCLUSIONS
We conclude that the direct administration of GM-CSF gene in limb ischemia had a strong therapeutic effect because it promoted the recovery of muscle mass, force and structure by mobilizing therapeutic cells and augmenting the number of vessels.
Sacramento
Chester Bittencourt
CB
Interdisciplinary Center for Gene Therapy, Federal University of São Paulo, São Paulo, Brazil.
Cantagalli
Vanessa Dionisio
VD
Grings
Mariana
M
Carvalho
Leonardo Pinto
LP
Baptista-Silva
José Carlos Costa
JC
Beutel
Abram
A
Bergamaschi
Cassia Toledo
CT
de Campos Junior
Ruy Ribeiro
RR
de Moraes
Jane Zveiter
JZ
Takiya
Christina Maeda
CM
Samoto
Vívian Yochiko
VY
Borojevic
Radovan
R
da Silva
Flavia Helena
FH
Nardi
Nance Beyer
NB
Dohmann
Hans Fernando
HF
Junior
Hamilton Silva
HS
Valero
Valderez Bastos
VB
Han
Sang Won
SW
D000208:Acute Disease; D000818:Animals; D004195:Disease Models, Animal; D005121:Extremities / Q000473:pathology; D015316:Genetic Therapy / Q000379:methods*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000008:administration & dosage*; D006410:Hematopoiesis / Q000187:drug effects; D007511:Ischemia / Q000628:therapy*; D051379:Mice; D018482:Muscle, Skeletal / Q000187:drug effects; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010957:Plasmids / Q000008:administration & dosage; D016896:Treatment Outcome
D016178:Granulocyte-Macrophage Colony-Stimulating Factor