Biomedical subjects

Catherine Verfaillie

Publications and source records attributed to Catherine Verfaillie.

3 recordsLinked to original sources

PubMed2005

Stem cell plasticity.

The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack of a clear definition for plasticity has led to confusion with several reports failing to demonstrate that a single cell can indeed differentiate into multiple lineages at significant levels. Further, differences between results obtained in different labs has cast doubt on some results and several studies still await independent confirmation. In this review, we critically evaluate studies that report stem cell plasticity using three rigid criteria to define stem cell plasticity; differentiation of a single cell into multiple cell lineages, functionality of differentiated cells in vitro and in vivo, robust and persistent engraft of transplanted cells.

Adult↗

PubMed2004

Applications of magnetic resonance imaging for cardiac stem cell therapy.

BACKGROUND: The latest generation of interactive cardiac magnetic resonance (MR) scanners has made cardiac interventions with real-time MRI possible. To date, cardiac MRI has been mostly applied to measure myocardial perfusion, viability, and regional function, but now the application of cardiac MRI can be extended to cardiovascular interventions. The purpose of this article is to illustrate the potential of MRI in stem cell therapy for cardiac restoration. METHODS: We have applied MRI to (1) interactively target myocardial injections with a novel stem cell delivery catheter, and to compare gadolinium/blue dye injections to pathology; (2) assess myocardial perfusion with MR first pass imaging in an infarct model treated with stem cell therapy versus control animals; (3) measure regional functional changes using myocardial tissue tagging in the same animals. RESULTS: We were able to demonstrate the feasibility and safety of myocardial injections under MR fluoroscopy. The intramyocardial distribution of the blue dye at necropsy correlated well with the extent of gadolinium, as detected with a three-dimensional inversion recovery MR pulse sequence for late enhancement immediately after contrast injection. Preliminary results show that myocardial perfusion reserve and regional wall motion improved in the stem-cell-treated group, compared to a control group. CONCLUSIONS: These preliminary results suggest that (1) injections into the LV myocardium can be performed under real-time MRI guidance using a directed catheter approach, and (2) regional myocardial perfusion and function, measured with MRI, both improve after stem cell therapy. This ongoing study demonstrates the potential of MRI for image-guided interventions, combined with detailed evaluation of anatomy, function, perfusion, and viability.

Animals↗

PubMed2002

A role for extrarenal cells in the regeneration following acute renal failure.

BACKGROUND: Recovery of renal function following acute tubular necrosis (ATN) is dependent on the replacement of necrotic tubular cells with functional tubular epithelium. The source of these new tubular cells is thought to be resident renal tubular cells. The discovery of pluripotent bone marrow-derived stem cells has led to a reexamination of the cellular source and processes involved in the recovery from organ injury. METHODS: To test the hypothesis in humans that extrarenal cells participate in the recovery following ATN, we examined the origin of tubular cells in male patients with resolving ATN who had received a kidney transplant from a female donor. Immunohistochmistry of kidney biopsies was performed to identify renal tubular epithelial cells (cytokeratin positive) and leukocytes (CD45 positive). Fluorescent in-situ hybridization was used to detect Y chromosome containing cells with DAPI serving as a nuclear stain. All staining was performed on the same section. RESULTS: The Y chromosome was detected in approximately 40% of tubular cell nuclei in male kidneys (positive control) and in no nuclei of female kidneys (negative control). In male recipients of female kidneys who developed ATN, 1% of tubules contained Y chromosome cells defined by their morphology, positive staining for cytokeratin, and negative staining for CD45. When present, multiple cells in a positive tubule stained for the Y chromosome. No Y chromosome containing tubular cells were seen in similar sex mismatched transplants in male recipients who did not develop ATN, suggesting that recipient derived cells do not routinely repopulate the transplanted kidney. CONCLUSIONS: This proof-of-principle clinical observation demonstrates that extrarenal cells can participate in the regenerative response following ATN. These findings provide rationale for the cellular therapy of acute renal failure.

Acute Kidney Injury↗