Characterization of mesenchymal stem or stromal cells: tissue sources, heterogeneity, and function

Urine-derived stem cells from patients alleviate lupus nephritis via regulating macrophage polarization in a CXCL14-dependent manner

AIM

Mesenchymal stem cells (MSC) exhibit hopeful therapeutic potential for the treatment of lupus nephritis (LN). Nevertheless, most MSC are harvested invasively and only transplantation of allogeneic MSC takes effect. Urine-derived stem cells (USC) can be obtained by noninvasive and safe access. Whether USC can be used for autologous stem cell transplantation to treat LN remains unknown.

MATERIALS AND METHODS

USC were harvested from healthy individuals, systemic lupus erythematosus (SLE) patients with no LN (NLN) and LN patients. The biological characteristics and immunomodulatory ability of three USC types were compared. Therapeutic value of USC for LN in MRL/lpr mice and influence of USC on macrophages were assessed. We further explored the mechanism of USC from LN patients (LN-USC) on macrophage polarization.

KEY FINDINGS

LN-USC exhibited faster proliferation and less apoptosis, significantly upregulated regulatory T cells (Treg) and downregulated antibody secreting cells (ASC). Importantly, LN-USC showed the best effect on LN in MRL/lpr mice among the three USC types. Additionally, LN-USC markedly downregulated M1 polarization of macrophages when injected into MRL/lpr mice or co-cultured with human acute monocytic leukemia cell (THP1)-derived M0 macrophages. Moreover, the regulative effect on macrophage polarization and therapeutic efficacy on LN were reversed after knocking down C-X-C motif chemokine ligand 14 (CXCL14) of LN-USC.

SIGNIFICANCE

These results suggested that transplantation of LN-USC alleviated LN in MRL/lpr mice via inhibiting M1 polarization of macrophages in a CXCL14-dependent manner, indicating that USC serve as a prospective candidate for autologous stem cell therapy of LN.

Advanced cell therapeutics are changing the clinical landscape: will mesenchymal stromal cells be a part of it?

During the past 15 years there have been dramatic changes in the medical landscape, particularly in oncology and regenerative medicine. Cell therapies have played a substantial part in this progress. Cellular immunotherapies can use immune cells, such as T cells or natural killer cells that, after functional modification ex vivo, exert powerful anti-cancer effects when given to the patient. Innovative technologies, such as re-programming terminally differentiated cells into pluripotent stem cells or into other cell types and applying specific enzymes to more precisely edit the human genome, are paving the way towards more potent cell and gene therapies.Mesenchymal stromal cells are promising cellular immunotherapeutics, which also have potential for use in tissue engineering strategies and other regenerative medicine applications. However, substantial gaps in our knowledge of their biology and therapeutic efficacy present major challenges to their sustainable implementation in the clinical routine.In this article, progress in the field of cell therapeutics during the past 15 years will be briefly discussed, with a focus on mesenchymal stromal cells, highlighting the impact of this field on patient care.