A summary of the Petriz lab research interests
In the last thirty years I’ve been involved in two main research projects on human stem cells. A number of data point to the existence of different classes of human stem cells with variable self-renewal potential and short- or long-term repopulating capacity. These observations led us to investigate the telomere length in highly purified human hematopoietic CD34+ cells, obtained from the mobilized peripheral blood of healthy donors, and from patients with multiple sclerosis (MS) undergoing autologous stem cell transplantation. We used flow cytometry-based fluorescent in situ hybridization (Flow-FISH) for the measurement of relative telomere length. We showed that a very small fraction of cells with very large telomeres was systematically identified in all samples of purified CD34+ cells, lending support to previous observations on the heterogeneity of the stem cell compartment
(FACS-based isolation of HSCs using Flow-FISH, in association with the mRNA expression analysis of gene expression in highly purified preparations of stem cell subsets on the basis of telomere length).
More
recently, I started my research on the Side Population (SP) stem
cells. ABCG2, a half-transporter that belongs to the ABC
transporter superfamily, is expressed in primitive stem cells, and
is responsible for the formation of a SP with a Hoechst 33342
fluorescent profile blocked in the presence of multidrug reversal
agents. SP cells are present in a wide variety of tissues and ABCG2
expression is believed to represent a common molecular mechanism
for stem cells possessing multi-organ plasticity. FACS-based
isolation of SP cells, in association with the mRNA expression
analysis of gene expression in highly purified preparations of stem
cell subsets -on the basis of ABCG2 expression- is providing us
important insights in SP biology. I am studying the single-cell
gene expression profile of SP cells to relate the expression of
specific genes to a particular cellular phenotype
(Flow cytometry based sorting for the isolation of normal and
cancer stem cells originated from the Side Population and its
association with the gene expression in highly purified
preparations of stem cell subsets).