Assessment of Short-Term Engraftment Potential of Ex Vivo Expanded Hematopoietic Stem Cells Using Normal Fetal Mouse in Utero Transplantation Model


Morteza Zarrabi, Ph.D., 1,2,#Elaheh Afzal, M.Sc., 2,#Mohammad Hassan Asghari, D.V.M., 3,#Marzieh Ebrahimi, Ph.D., 1,*
Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
Royan Stem Cell Technology Company, Cord Blood Bank, Tehran, Iran
Animal Core Facility, Reproductive Biomedicine Research Center, Royan Institute for Animal Biotechnology, ACECR, Tehran, Iran
Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
Royan Stem Cell Technology Company, Cord Blood Bank, Tehran, Iran
Animal Core Facility, Reproductive Biomedicine Research Center, Royan Institute for Animal Biotechnology, ACECR, Tehran, Iran
* Corresponding Address: P.O.Box: 16635-148 Department of Stem Cells and Developmental Biology Royan Institute for Stem Cell Biology and Technology ACECR TehranIran Email: mebrahimi@royaninstitute.org

The first three authors equally contributed to this work.

The Cell Journal (Yakhteh) is an open access journal which means the articles are freely available online for any individual author to download and use the providing address. The journal is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported License which allows the author(s) to hold the copyright without restrictions that is permitting unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Zarrabi Morteza, Afzal Elaheh, Asghari Mohammad Hassan, Ebrahimi Marzieh. Assessment of Short-Term Engraftment Potential of Ex Vivo Expanded Hematopoietic Stem Cells Using Normal Fetal Mouse in Utero Transplantation Model. Cell J. 2019; 21(3): 259-267.

Abstract

Objective:

Ex vivo expansion is a promising strategy to overcome the low number of human umbilical cord blood hematopoietic stem cells (hUCB-HSCs). Although based on the obtained results in unnatural physiological condition of irradiated genetically immune-deficient mouse models, there has always been concern that the expanded cells have less engraftment potential. The purpose of this study was to investigate effect of common ex vivo expansion method on engraftment potential of hUCB-mononuclear cells (MNCs), using normal fetal mouse, as a model with more similarity to human physiological conditions.

Materials and Methods:

In this experimental study, briefly, isolated hUCB-MNCs were cultured in common expansion medium containing stem cell factor, Flt3 ligand and thrombopoietin. The unexpanded and expanded cells were transplanted to the fetal mice on gestational days of 11.5-13.5. After administration of human hematopoiesis growth factors (hHGFs), presence of human CD45+ cells, in the peripheral blood of recipients, was assessed at various time points after transplantation.

Results:

The expanded MNCs showed 32-fold increase in the expression of CD34+38- phenotype and about 3-fold higher clonogenic potential as compared to the uncultured cells. Four weeks after transplantation, 73% (19/26) of expanded-cell recipients and 35% (7/20) of unexpanded-cell recipients were found to be successfully engrafted with human CD45+ cells. The engraftment level of expanded MNCs was significantly (1.8-fold) higher than unexpanded cells. After hHGFs administration, the level was increased to 3.2, 3.8 and 2.6-fold at respectively 8, 12, and 16 weeks of post transplantation. The increased expression of CXCR4 protein in expanded MNCs is a likely explanation for the present findings.

Conclusion:

The presented data showed that expanded MNCs compared to unexpended cells are capable of more rapid and higher short-term engraftment in normal fetal mouse. It could also be suggested that in utero transplantation (IUT) of normal fetal mice could be an appropriate substitute for NOD/SCID mice in xenotransplantation studies.