Remarkable up-regulation of 1-antichymotrypsin in brains of scrapie agent 139A infected mice

Objective To understand the potential alterations of 1-antichymotrypsin (ACT) levels in the brains of scrapie agent 139A infected mice. Methods By using Western blot, immunohistochemistry assay, indirect immunofluorescent assay and confocal microscope assays, we analyzed the characteristics of the expressions and distributions of 1-ACT in the brains of scrapie agent 139A-infected mice. Results Compared with the normal controls, 1-ACT-specific Western blot showed that the levels of 1-ACT were remarkably up-regulated in the brains of scrapie-infected mice in a time-dependent manner during the incubation period after prion infection. Immunohistochemistry assay showed that the brain 1-ACT were mainly distributed in the regions of cortex, thalamus and cerebellum. Indirect immunofluorescent assay showed large amounts of complement C3 positive signals in the brain slices of 139A-infected mice, and confocal microscope assays further found brain 1-ACT to be colocalized well with complement C3. Conclusion Remarkable up-regulation of 1-ACT in the brains of scrapie agent 139A infected mice was observed at end stage of the infection.