Bone Marrow Mesenchymal Stem Cells Enhance the Differentiation of Human Switched Memory B Lymphocytes into Plasma Cells in Serum-Free Medium

Figure 7

Cytokines and immunoglobulins secretions. All analyses were done at the end of the differentiation phase (day 20). (a and b) CXCL12 and TGF-β1 contents were determined in cell culture supernatants of differentiated cells. Control (Ctrl) corresponds to the supernatant of MSC cultured in α-MEM for 4 days in the absence of B lymphocytes. All other conditions correspond to B lymphocytes in coculture with MSC or L4.5 cells or B lymphocytes cultured in the presence of MSC which were seeded in the upper chamber of transwell (Trans). Cultures were done in parallel and at 21% or 8% O₂. (c–g) IgG1, IgG2, IgG3, and IgG4 secretion were determined in cell culture supernatants on day 20. Statistical analyses were performed using a Dunn multiple comparison -test (, , and ). No significant differences were observed between MSC in direct contact and transwell assays at 8% O₂ (; Kruskal-Wallis -test). Except for the results of MSC in direct contact, which were obtained from four independent experiments, all data are from five independent experiments and all are presented as means ± SEM.

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