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

Figure 5

Two subsets of differentiated B lymphocytes can be distinguished according to their size and granularity. Switched memory B lymphocytes were cultured as described in Figure 2(a) during the expansion and transition phases. For the differentiation phase, cells were grown in the presence of L4.5 cells or MSC. All assays were done in parallel at 21% and 8% O₂ and analyses were done on day 20. (a) and (b) Profiles of populations A and B as revealed by size (FSC) and granularity (SSC) parameters. (c) and (d) Expression of CD38 and CD138 and (e) and (f) expression of CD31 and CD39 were determined and corroborated with populations A and B. Profiles shown in (c)–(f) are representative of five independent samples. (g) Relative frequencies (RF) of CD38^highCD138⁺ were determined for B populations using this formula: . (h) Viability in A and B populations is shown for all conditions tested. Results in (g) and (h) are presented as the mean ± SEM of five independents experiments. Statistical analyses were done using Dunn multiple comparison -test with .

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)