Dynamic cell-cell interactions between cord blood haematopoietic progenitors and the cellular niche are essential for the expansion of CD34⁺, CD34⁺CD38⁻and early lymphoid CD7⁺cells

Abstract

Most clinical applications of haematopoietic stem/progenitor cells (HSCs) would benefit from their ex vivo expansion to obtain a therapeutically significant amount of cells from the available donor samples. We studied the impact of cellular interactions between umbilical cord blood (UCB) haematopoietic cells and bone marrow (BM)-derived mesenchymal stem cells (MSCs) on the ex vivo expansion and differentiative potential of UCB CD34(+)-enriched cells. UCB cells were cultured: (a) directly in contact with BM MSC-derived stromal layers (contact); (b) separated by a microporous membrane (non-contact); or (c) without stroma (no stroma). Highly dynamic culture events occurred in HSC-MSC co-cultures, involving cell-cell interactions, which preceded HSC expansion. Throughout the time in culture [18 days], total cell expansion was significantly higher in contact (fold increase of 280 + or - 37 at day 18) compared to non-contact (85 + or - 25). No significant cell expansion was observed in stroma-free cultures. CD34(+) cell expansion was also clearly favoured by direct contact with BM MSCs (35 + or - 5- and 7 + or - 3-fold increases at day 18 for contact and non-contact, respectively). Moreover, a higher percentage of CD34(+)CD38(-) cells was consistently maintained during the time in culture under contact (8.1 + or - 1.9% at day 18) compared to non-contact (5.7 + or - 1.6%). Importantly, direct cell interaction with BM MSCs significantly enhanced the expansion of early lymphoid CD7(+) cells, yielding considerably higher (x3-10) progenitor numbers compared to non-contact conditions. These results highlight the importance of dynamic cell-cell interactions between UCB HSCs and BM MSCs, towards the maximization of HSC expansion ex vivo to obtain clinically relevant cell numbers for multiple settings, such as BM transplantation or somatic cell gene therapy.

Evaluating Interaction of Cord Blood Hematopoietic Stem/Progenitor Cells with Functionally Integrated Three-Dimensional Microenvironments

“…1E). In addition, and in similarity to our previous findings 35, CB‐HSPC grown in culture media alone did not proliferate and had decreased viability with the time in culture (data not shown).…”

Galectin-9 ameliorates herpes simplex virus-induced inflammation through apoptosis

“…Gal-9 increased CD11c, a marker of dendritic cells (O'Keeffe et al 2003), in the lymph nodes of BD-like mice, although this increase was not statistically significant. CD34 is a marker of cell-cell adhesion and is found on hematopoietic cells (da Silva et al 2010). CD34 also interacts with L-selectin, an important factor in inflammation (Koenig et al 1999), and is localized by endothelial cells of microvessels in rheumatoid and osteoarthritic synovia and Crohn's disease colon (Middleton et al 2005).…”

Mesenchymal Stem Cells Secreting Angiopoietin-Like-5 Support Efficient Expansion of Human Hematopoietic Stem Cells Without Compromising Their Repopulating Potential

“…MSCs from bone marrow [6], Wharton's jelly of umbilical cord segments [7], cord blood [8], and other fetal tissues [9][10][11] have been shown to support expansion of human HSCs [6][7][8][11][12][13][14][15][16]. Depending on the coculture conditions, 80-800-fold increase in total cell number and 4-100-fold increase in CD34 þ cells were reported [17][18][19]. The highest expansion was achieved by culturing human HSCs with MSCs in a 3D configuration using a woven mesh where *100-fold expansion of CD34 þ cells was achieved in 10 days [5].…”