Figure 4.

Increased antigen-presenting cell (APC) function in asthma-susceptible DCs. Splenic CD11c⁺ DCs were purified from neonatal donor groups, as well as from adult control animals. Adult asthmatic females that received two injections of OVA and repeated OVA aerosol challenges (AsAd) and normal control females (NAd) were used as positive and negative controls, respectively. DCs from 14-day-old allergen-naive offspring (AsBa14 and NoBa14) constitute the main study groups, and were incubated with OVA and responding DO11.10 T cells. The resulting proliferation of responder DO11.10 T cells was measured using [³H]thymidine incorporation as counts per minute (CPM) and normalized to a range of 0–1 via minimum–maximum normalization to assure cross-experiment comparability. Normalized CPM counts indicate that DCs from adult asthmatics (AsAd) had increased antigen-presentation activity to T cells compared with those from normal adult controls (Norm; P < 0.01). Remarkably, DCs from 14-day-old allergen-naive neonates born to asthmatic mothers (AsBa14) showed increased APC activity compared with 14-day-old neonates of normal mothers (NoBa14). At least three animals per group were used; data are representative of four separate experiments. *P < 0.05. ***P < 0.005.