Figure 8.
Heritability of IFN-γ promoter methylation patterns and IFN-γ mRNA expression levels in families of CD8+ T cells. CD8+ LN T cells from normal mice were separated by FACS® into CD44low and CD44high subpopulations, and seeded by automated deposition as single cells into stimulation cultures for 4 d as described in Materials and Methods. Parental CD8+ T cell clones were then subcloned by micromanipulation, with harvesting of progeny subclones after 2–3 d of further growth. Families of clones derived from CD44low cells are shown in A, whereas those derived from CD44high cells are shown in B. Each family has a separate letter code with the parent clone (0) and sibling subclones (1–6) numbered. The parent clone for family C did not survive micromanipulation. Methylation patterns and mRNA levels for the families of clones are shown as described in the legends to Figs. 4 and 5.