Human mesenchymal and murine stromal cells support human lympho-myeloid progenitor expansion but not maintenance of multipotent haematopoietic stem and progenitor cells

Abstract

A major goal in haematopoietic stem cell (HSC) research is to define conditions for the expansion of HSCs or multipotent progenitor cells (MPPs). Since human HSCs/MPPs cannot be isolated, NOD/SCID repopulating cell (SRC) assays emerged as the standard for the quantification of very primitive haematopoietic cell. However, in addition to HSCs/MPPs, lympho-myeloid primed progenitors (LMPPs) were recently found to contain SRC activities, challenging this assay as clear HSC/MPP readout. Because our revised model of human haematopoiesis predicts that HSCs/MPPs can be identified as CD133 C CD34 C cells containing erythroid potentials, we investigated the potential of human mesenchymal and conventional murine stromal cells to support expansion of HSCs/MPPs. Even though all stromal cells supported expansion of CD133 C CD34 C progenitors with long-term myeloid and long-term lymphoid potentials, erythroid potentials were exclusively found within erythro-myeloid CD133 low CD34 C cell fractions. Thus, our data demonstrate that against the prevailing assumption co-cultures on human mesenchymal and murine stromal cells neither promote expansion nor maintenance of HSCs and MPPs.

Optimisation of imaging flow cytometry for the analysis of single extracellular vesicles by using fluorescence‐tagged vesicles as biological reference material

“…HEK293T cells were cultured in DMEM (containing Glutamax‐I and sodium pyruvate; 4.5 g/L Glucose; Invitrogen) supplemented with 10% FBS (Biochrom) and 1× Penicillin/Streptomycin (ThermoFisher Scientific). Primary human bone marrow–derived mesenchymal stromal cells (MSCs) raised from bone marrow (BM) samples were cultured in DMEM (containing Glutamax‐I and sodium pyruvate; 1 g/L Glucose; Invitrogen) supplemented with 10% pooled human platelet lysate (hPL), 1× Penicillin/Streptomycin (ThermoFisher Scientific) and 0.1% Heparin, and were confirmed as bona fide MSCs as described previously [47,48]. All culture media were filtered through 0.22 µm filters before usage.…”

Potential therapeutic application of mesenchymal stem cell-derived exosomes in SARS-CoV-2 pneumonia

“…These comprise the source of MSC-Exo. MSCs, the heterogeneous cells, can be obtained from various tissues, even though MSCs isolated from the same sources may vary in entity and functionality [ 89 , 90 ]. For example, several donor-derived bone marrow MSCs release exosomes with distinct cytokine profile content [ 91 ].…”

Human multipotent hematopoietic progenitor cell expansion is neither supported in endothelial and endothelial/mesenchymal co-cultures nor in NSG mice

“…Using this definition as read-out to identify multipotent human HSPCs following in vitro expansion, we recently re-evaluated the reported potential of murine stromal cell lines (AFT024, OP9, MS5) as well as human mesenchymal stromal cell (MSCs) from various tissues to support the ex vivo expansion of UCB-derived HSCs/MPPs 15 . In these experiments, none of the tested culture conditions supported the expansion or maintenance of primitive CD133 + HSPCs with erythroid differentiation potentials.…”