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

Figure 3

Effects of eosinophil and mesenchymal stem cells on the differentiation of switched memory B lymphocytes. Switched memory B lymphocytes were cultured as described in Figure 2(a) for the expansion and transition phases. Then, cells were exposed to L4.5 cells (L) alone or in combination with EOL-1 cells (E) or EOL-1 cells plus bone marrow MSC (M) during the differentiation phase. During that phase, all cultures were done in 21% and 8% O₂ condition. (a) Plasma cell content was determined on day 20 by excluding debris and dead cells. Analysis relative to CD38⁺CD138⁺ cells is gated within the upper right (UR) quadrant, and results are shown in (b) and (d). Results for CD38^hiCD138^hi population, gated within R1 (red square), were analysed in (c) and (e). (g) Analysis for CD138^hi cells gated within R2 (green square). (b) Frequencies of CD38⁺CD138⁺, (c) CD38^hiCD138^hi, (d-e) CD31⁺, (f) CD138⁺, and (g) CD138^hi populations are shown for 7 independent experiments for cells cultured in the presence of L4.5 cells alone and for 5 independent experiments for LE and LEM assays. Statistical analyses were done using a Dunn multiple comparison -test with values as indicated: , , and . Data are presented as means ± SEM.

(a)

(b)

(c)

(d)

(e)

(f)

(g)