Biomedical Engineering Reference
In-Depth Information
A number of possible mechanisms have been proposed: (a) transdifferentiation of
stem cells into cells of other lineages such as endothelial cells or cardiomyocytes
resulting in the formation of new tissue; (b) mobilization of tissue-specific stem/
progenitor cells from the BM that home to the damaged tissue and participate in
tissue/organ regeneration [
102
]; (c) fusion of the stem cells with cells of the target
tissue giving rise to new cells [
103,
104
], and/or (d) creation of a millue, perhaps by
secretion of growth factors, that enhances regeneration of endogenous cells [
105,
106
]. Though the exact mechanism still has to be defined the evidence is conclusive
that mobilized bone marrow-derived adult stem cells are responsible for the tissue
regeneration and protection in these disease models.
In summary, current challenges for cell-based therapy in cardiac repair include
identifying the origins of the novel cardiac progenitor and stem cells found within
the heart, pinpointing the biologically active cells from bone marrow and other
mixed populations, optimizing cell mobilization and homing, augmenting grafted
cells' survival, defining the cues for cardiac differentiation, promoting donor cell
proliferation ex vivo (or, if safe, in vivo), and exploiting cell therapy as a platform
for secretory signals. In conclusion: we need a lot of basic research and randomized
clinical trials to define the exact role of this probably revolutionary therapy for isch-
emic heart disease.
Referen ces
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Neovascularization of ischemic myocardium by human bone-marrow-derived angioblasts
prevents cardiomyocyte apoptosis, reduced remodelling and improves cardiac function. Nat
Med 7:430-436
2. Obradovic S, Balint B, Rusovic S, Ristic-Angelkov A, Romanovic R, Baskot B et al (2004)
The first experience with autologous bone marrow derived progenitor cell transfer for myo-
cardial regeneration after acute infarction. Anesth Reanim Transf 32(1-2):39-50
3. Dai W, Kloner RA (2006) Myocardial regeneration by embryonic SC transplantation: present
and future trends. Expert Rev Cardiovasc Ther 4(3):375-383
4. Rogers I, Casper RF (2004) Umbilical cord blood SCs. Best Pract Res Clin Obstet Gynaecol
18(6):893-908
5. Rangappa S, Fen C, Lee EH, Bongso A, Sim EK (2003) Transformation of adult mesenchy-
mal stem cells isolated from the fatty tissue into cardiomyocytes. Ann Thorac Surg
75:775-779
6. Lakshmipathy U, Pelacho B, Sudo K, Linehan JL, Coucouvanis E, Kaufman DS, Verfaillie CM
(2004) Efficient transfection of embryonic and adult stem cells. Stem Cells 22(4):531-543
7. Hierlihy AM, Seale P, Lobe CG, Rudnicki MA, Megeney LA (2002) The post-natal heart
contains a myocardial stem cell population. FEBS Lett 520:239-243
8. Yau TM, Tomita S, Weisel RD, Jia Z-Q, Tumiati LC, Mickle DAG et al (2003) Beneficial
effect of autologous cell transplantation on infarcted heart function: comparison between
bone marrow stromal cells and heart cells. Ann Thorac Surg 75:169-177
9. Dowell JD, Rubart M, Pasumarthi KBS, Soonpaa MH, Field LJ (2003) Myocyte and myo-
genic stem cell transplantation in the heart. Cardiovasc Res 58:333-347
10. Shintani S, Murohara T, Ikeda H, Uenoi T, Honma T, Katoh A et al (2001) Mobilization of
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