Table 1.

Induction of Myocarditis or Protection by Cardiac Myosin Peptide S2-16

Pretreat-ment	Immunization	Positive/total	Mean histological score (1+–4+)* ± SD
S2-16:IFA	S2-16:CFA	0/6	0†
PBS:IFA	S2-16:CFA	5/6	2.6 ± 1.6
S2-1:IFA	S2-16:CFA	2/3	2.5 ± 2
S2-16:CFA	S2-16:CFA	1/3	0.3 ± 0.3
PBS:IFA	PBS:CFA	0/3	0‡

Lewis rats were pretreated with S2-16 peptide emulsified in IFA. Control groups of rats were pretreated with PBS or S2-1 peptide in IFA, or S2-16 in CFA. Fourteen days later, rats were challenged by immunization with S2-16 peptide or PBS in CFA as described in Materials and Methods. Animals were killed 21 days after challenge. Myocarditis was identified in fixed heart tissue sections by histopathological examination. In vitro analysis of proliferation and cytokine production of splenocytes are shown in Figure 1. 

^*Lesions were scored histologically based on the following scale: 0, normal; 1, mild (less than 5% of cross section involved); 2, moderate (5 to 10% of cross section involved); 3, marked (10 to 25% of cross section involved); 4, severe (greater than 25% of cross section involved). 

^†P < 0.005 for S2-16:IFA/S2-16:CFA-treated group versus PBS:IFA/S2-16:CFA-treated control group (Mann-Whitney test was used for in vivo results). 

^‡P < 0.05 for PBS:IFA/PBS:CFA-treated group versus PBS:IFA/S2-16:CFA-treated group.