Figure 1.
Athymic nude mice had smaller lesions after cutaneous infection with S. aureus.
(A) Athymic nude mice from the Balb/c background had smaller lesions, compared wild type Balb/c mice, after infection with S. aureus. (B) Athymic nude mice from the C57Bl/6 background had smaller lesions, compared with wild type C57Bl/6 mice, after infection with S. aureus. (C) Photographs of representative lesions from wild type and athymic nude mice from the Balb/c background. Bars represent 10 mm. Data are presented as mean ± SEM. * indicates p<0.01. N=8 mice/group.
Figure 2.
Athymic nude mice had less inflammation but no difference in bacterial recovery from skin lesions.
Wild type and athymic nude mice from the Balb/c background (n=10 mice/group) were sacrificed 3 days after inoculation with S. aureus. Athymic nude mice had smaller skin lesions (A) but no difference in bacterial burden in the lesions (B), compared with wild type mice. (C) The lesion size was not correlated with bacterial burden in wild type or athymic nude mice. The skin lesions of athymic nude mice had lower levels of IL-17A (D), CXCL1 (E), and myeloperoxidase (F), compared with wild type mice. Data are presented as mean ± SEM.
Figure 3.
Local factors, rather than systemic immunodeficiency, mediated the smaller skin lesions in athymic nude mice.
(A) There was no difference in lesion size between C57Bl/6j (wild type) and TCR βδ (-/-) mice after infection with S. aureus (n=5-10 mice/group). Data are presented as mean ± SEM. (B) T cell deficiency did not explain the smaller lesions observed in athymic nude mice, as adoptive transfer of T cells into naïve Balb/c athymic nude mice prior to infection with S. aureus did not result in altered lesion size (n=8 mice/group). Data are presented as mean ± SEM. * indicates p<0.01 compared with wild type mice. (C) Photographs of representative lesions from wild type mice and from nude mice that received PBS or adoptive transfer of T cells prior to infection with S. aureus. The black bars indicate 10 mm. (D) There was no difference in the mortality rate of athymic nude or wild type Balb/c mice in a mouse model of S. aureus necrotizing pneumonia (n=8 mice/group).