Figure 1.

CVB1–6 vaccine does not increase pancreatic islet inflammation (insulitis) in prediabetic NOD mice. Female NOD mice (mean age, 5.5 weeks; range, 5.1–6.3 weeks) were mock-vaccinated with buffer (n = 13) or vaccinated with CVB1–6 vaccine (n = 8) by interscapular injection on three occasions (on days 0, 14, and 28 [n = 3] or on days 0, 21, and 35 [n = 5]). Mice were monitored until 12 weeks of age (6–8 weeks after the first vaccination). A: Average virus-neutralizing antibody titers in the serum of CVB1–6 vaccinated mice against the six CVB serotypes on day 41/42 after the first vaccination dose. Sera from mock-vaccinated mice had no virus-neutralizing capacity (data not shown). Shown are the mean ± SD neutralizing antibody titers, with individual mice represented by a single symbol. The blue symbols represent neutralizing antibody titer data that were also published previously (13). B–D: Sections of formalin-fixed paraffin-embedded pancreas were scored in a blinded manner for islet immune cell infiltration as described in research design and methods. B: Representative images of islets with different scores as described in research design and methods and esm methods. Scale bar = 100 μm. C: The total score per pancreas was divided by the total number of islets scored. Shown are the mean ± SD scores, with each score from an individual animal represented by a single symbol; buffer (n = 13) or CVB1–6 vaccine (n = 8). No statistically significant difference was found between the groups using an unpaired t test. D: Data show the percentage of islets from each mouse that fall into each insulitis category assessed as illustrated in B. Islets were scored as intact (0), peri-insulitis (1), insulitis (2), or destroyed (3). No statistically significant differences were found between the groups using two-way ANOVA with the Šidák multiple comparison test.