Fig. 6.

Heterotypic DENV-1-specific CD8⁺ T lymphocytes are sufficient to elicit signs of severe dengue disease in DENV-2 infected mice. (a–g) C57BL/6 mice were transferred i.v. with CD4⁺ or CD8⁺ T cells from DENV-1 or DENV-2 infected mice, and 1 day later were infected with DENV-2 i.p. (b–g) Hematological and biochemical parameters were measured at different days post-secondary infection with DENV-2 (0, 4, and 7 days). (h–m) CD8α −/− mice were transferred with CD8⁺ T cells from DENV-1 infected TNF-α −/− or C57BL/6 mice, and 1 day later were challenged with DENV-2 i.p. (i–m) Hematological and biochemical parameters were measured at 7 days post-secondary infection with DENV-2. ALT: alanine aminotransferase; AST: aspartate aminotransferase; CK: creatine kinase; LDH: lactate dehydrogenase. Values represent means ± SEM (n = 4–6/group). Two independent experiments were performed that showed similar results. *p < 0.05, **p < 0.01, ***p < 0.001, determined by (b–g) one-way ANOVA (dashed line) and Bonferroni's multiple comparison post-test (solid line) or (i–m) Student's un-paired t-test.