Figure 2.

CS and DTH were inhibited by local depletion of C in ears by CVF injection. (A) CBA/J mice (4/group) were actively contact sensitized with PCl applied topically to the shaved chest and abdomen. 4 d later mice were skin challenged to elicit CS responses by painting both ears with PCl (groups C and D). Subsequent CS ear swelling responses were measured with a dial caliper by comparing thickness before vs. 2 and 24 h after challenge. Net ear swelling was calculated by subtracting ear thickness before challenge from that at 2 and 24 h. PBS or CVF (5 μg/20 μl) was injected directly into the ears s.c. with a 30 gauge, 1/2′′ needle, 48 h before challenge (groups B and D). (B) TNP-SRBC (10⁵ cells) were injected i.v. to immunize BDF₁ mice (4/group) which were challenged s.c. 5 d later in both hind footpads with 10⁸ TNP-SRBC. Footpad swelling was measured with a dial caliper before and 24 h after challenge. PBS or CVF (1 μg/40 μl) was injected locally s.c. 48 h before footpad challenge. *P <0.05, **P <0.01, compared to 2- and 24-h positive immune and Ag-challenged controls which were injected with PBS (group C).