Distinct Repopulation Activity in Hu-Mice Between CB- and LPB-CD34 Cells by Enrichment of Transcription Factors.

BACKGROUND AND OBJECTIVES

Human CD34 hematopoietic stem cells can reconstitute the human hematopoietic system when transplanted into immunocompromised mice after irradiation. Human leukapheresis peripheral blood (LPB)- and cord blood (CB)-derived CD34 cells have a similar capacity to reconstitute myeloid lineage cells in a humanized mice (hu-mice) model. However, potent stem cells, such as CB-CD34 cells, efficiently reconstitute the lymphoid system in vivo compared to LPB-CD34 cells. Modeling the human hematolymphoid system is vital for studying immune cell crosstalk in human xenografted mice, with CB-CD34 cells used as an optimized cell source because they are essential in reconstituting lymphoid lineage cells.

METHODS AND RESULTS

In this study, we established hu-mice that combined human characteristics with long-term survival and investigated the efficiency of the engraftment of lymphoid lineage cells derived from LPB- and CB-CD34 cells in the bone marrow, spleen, and LPB. We found an overall increase in the transcriptional activity of lymphoid lineage genes in CB-CD34 cells. Our results revealed that potent CB-CD34 cells displaying a general upregulation of the expression of genes involved in lymphopoiesis could contribute to the hematolymphoid system in the humanized mice model with longevity.

CONCLUSIONS

Our data suggest that humanized mouse model by usage of CB-CD34 cells displaying high expression of TFs for lymphoid lineage cells can contribute to study the immune response against lymphocytes.