Figure 1.

DSCC stimulates reduced alloimmune responses and promotes beta cell survival in vitro. (a) Immune privilege related genes were expressed in DSCC. Hair follicle dermal sheath cup cells (DSCC), dermal papilla (DP), and dermal sheath (DS) cell gene expression were examined relative to nonfollicular fibroblasts (FB). Values were obtained using the 2^−ΔΔCT fold change method. For standard error (SE), the standard deviation of relevant samples was divided by the square root of the number of samples. The calculation for error bars was 2^{−ΔΔCT + SE} minus fold change or fold change minus 2^{−ΔΔCT − SE} to find the range of difference. The fold change was generated from duplicated values (n = 3). (b) DSCC significantly inhibited allogeneic leukocyte IFNγ secretion relative to FB. DSCC or FB from B6 (2 × 10⁴) were cocultured with splenic leukocytes (Balb/c, 2 × 10⁵) for 5 days. IFNγ detected in supernatant was significantly less in the presence of DSCC than FB. Data are shown as mean pg/mL IFNγ of three different experiments ± SEM, with Student t-test showing significance, ^∗ P < 0.05. Percentage of IFNγ expressing cells in CD4⁺ or CD8⁺ subsets after 5 days of coculture was presented by flow cytometric analysis. Representative dot plots and accumulated data from CD4⁺IFNγ ⁺ or CD8⁺IFNγ ⁺ cell populations are shown. (c) DSCC preserved beta cell function. DSCC or FB from B6 mice were cocultured with islets from Balb/c mice; the ability of insulin secretion was measured by static incubation at 3 and 7 days and relative gene expression was detected by qPCR at day 7. A similar insulin secretion upon glucose stimulation was detected at day 3. However, better insulin secretion was observed at day 7 with 20 mM glucose stimulation. Increased insulin mRNA and decreased Fas and Bax mRNA gene expression were detected at culture day 7. BMP6: bone morphogenetic protein 6; Fgf2: fibroblast growth factor 2; Il1ra: interleukin 1 receptor antagonist; Inhba: Inhibin beta A; Tap2: transporter associated with antigen processing. Data represent 3 independent experiments and are expressed as means ± SEM. Statistical significance was determined by Student t-test, ^∗ P < 0.05.