Table 2.

Histological Severities of EAC Induced by Immunization with the Peptide Mixtures, Synthetic Peptides, and Recombinant CC2*

Group	Antigen	Sampling	Incidence	Inflammation	Fibrosis
A	Mix 1 (P1 to P3)	3 weeks	1/3	0.7 ± 0.7	0
B	Mix 2 (P4 to P6)	3 weeks	1/3	0.3 ± 0.3	0
C	Mix 3 (P7 to P9)	3 weeks	1/3	0.2 ± 0.2	0
D	Mix 4 (P10 to P12)	3 weeks	3/3	2.5 ± 1.2	0
E	P10	Day 17	0/3	0†	0
F	P11	Day 17	1/3	0.2 ± 0.2†	0
G	P12	Day 17	4/4	2.0 ± 0.4†	0
		6 weeks	6/6	1.8 ± 0.4†	1.8 ± 0.6‡
H	P12-KLH	4 weeks	2/3	0.7 ± 0.3	0.7 ± 0.3
		6 weeks	3/3	1.3 ± 0.3†	0.8 ± 0.4‡
I	CC2	Day 17	5/5	4.1 ± 0.4†	1.5 ± 0.4
		6 weeks	6/6	3.8 ± 0.2†	4.1 ± 0.2‡

^*Lewis rats were immunized once with mixtures 1, 2, 3, and 4 that had consisted of peptides 1 to 3, 4 to 6, 7 to 9, and 10 to 12, respectively (100 μg of each peptide), in CFA in the foot pads along with intraperitoneal injection of pertussis toxin (2 μg). Because mix 4 showed carditogenicity, each peptide in the mixture (P10, P11, and P12) was tested in a similar manner. For comparison, the results obtained with recombinant C-protein fragment 2 are also shown. The denominators in the incidence column represent the number of rats used for each experiment. 

^†Analysis of variance and multiple comparison (Scheffe’s F-test) were performed, and significant differences were noted in the following combinations: P10 versus CC2, P = 0.002; P11 versus CC2, P = 0.0001; P12 versus CC2, P = 0.008 on day 17; P12 versus CC2, P = 0.003; P12-KLH versus CC2, P = 0.003 at 6 weeks. 

^‡Significant differences were noted in the following combinations: P12 versus CC2, P = 0.011; P12-KLH versus CC2, P = 0.004 at 6 weeks.