SPEA-induced histopathology for HLA-DQ8 mice. C57BL/6 or HLA-DQ8 transgenic mice were challenged intranasally with PBS or SPEA, and lung tissue was collected in buffered formaldehyde, embedded in paraffin, sectioned, and stained with hematoxylin and eosin. (A and B) SPEA-challenged C57BL/6 mice (1 μg/application); (C and D) SPEA-challenged HLA-DQ8 mice (1 μg/application); (E and F) SPEA-challenged HLA-DQ8 mice (2 ng/application). (A, C, and E) Lower magnification; (B, D, and F) higher magnification.