In Vivo Studies
BALB/c mice were injected intravenously (i.v.) with a red blood cell-depleted single-cell spleen suspension (2.5 x 107 cells) (Castro etal., 2000) from DO11.10 WT or STAT-deficient mice. After 48 hr, they were injected subcutaneously with PBS or with OVA protein (5 mg) plus LPS (5 mug). The inguinal lymph nodes were removed 48 hr later. A single-cell suspension (1 x 106 cells) was restimulated for 24 or 48 hr with 1 muM or 3 muM of OVA and with BrefeldinA for the last 6 hr. Half of the supernatant was removed before the addition of BrefeldinA for use in an ELISA assay. The cells were fixed and stained as before. Those positive for KJ1-26-Bio and for CD4-PerCP were gated, and IFN-gamma and IL-10 staining was examined for this population and analyzed as before. 
