Detection of Disease-associated Prion Protein in the Optic Nerve and the Adrenal Gland of Cattle with Bovine Spongiform Encephalopathy by Using Highly Sensitive Immunolabeling Procedures

Abstract

A sensitive immunohistochemical procedure, the tyramide signal amplification (TSA) system, was applied to detect the localization of immunolabeled disease-associated prion protein (PrPSc) in cattle affected with bovine spongiform encephalopathy (BSE). In this procedure, immunolabeling could be visualized in the optic nerve and the adrenal medulla. In the optic nerve, the dual immunofluorescent technique showed that the granular PrPSc was occasionally detected in the astrocytes, microglia, and myelin sheath adjacent to the axon. Clustered PrPSc was also scattered in association with microglial cells and astrocytes of the optic nerve. In the adrenal gland, PrPSc immunolabeling was confined within the sympathetic nerve fibers and endings. The results suggest that (1) PrPSc might centrifugally spread within and between glial cells and/or the non-axonal (also known as ad-axonal) region of nerve fibers, rather than the axonal and/or extracellular space pathway in the optic nerve, and (2) the sympathetic innervations might be important for the trafficking of BSE agent in the adrenal glands of cattle. This study also suggests that tyramide-based immunochemical analysis should be performed to detect immunolabeled PrPSc in the extracerebral tissues of BSE-affected cattle.

Identification of the first case of atypical scrapie in Japan

“…In addition, granular PrP Sc was observed by dual immunofluorescence and found to be located at the periphery of axons, suggestive of an ad-axonal location in the white matter of the spinocerebellar tract and the olivocerebellar tract (Fig. 2E) [22]. Association of PrP Sc with either astrocytes or microglia [23] was not detected in the brainstem (data not shown), agreeing with other reports of atypical scrapie cases [3, 25].…”

“…The blotted membranes were probed with the monoclonal antibody (mAb) P4 (R-Biopharm, Darmstadt, Germany) according to a previously described method [23]. IHC for PrP Sc was performed using the mAb T1 [27] or F99/97.6.1 (VMRD, Pullman, WA, U.S.A.) as previously described [22,23,24]. Additionally, formalin-fixed and paraffin-embedded tissue sections were stained with an anti- Listeria monocytogenes (Lm) polyclonal antibody [1] and a secondary Alexa Fluor 546-conjugated antibody for dual immunofluorescence.…”

When Tissue Antigens and Antibodies Get Along

“…Modifications using fluoresceinated tyramide result in marked reduction or ablation of background from endogenous biotin. 139,140,259,389 Immuno-Rolling Circle Amplification. Rolling circle amplification (RCA) increases the signal of the immunologic reaction without increasing the noise (background) that can occur with the tyramide amplification method.…”

Membrane Toxicity of Abnormal Prion Protein in Adrenal Chromaffin Cells of Scrapie Infected Sheep

“…Recent studies have demonstrated that ganglion cells from within the adrenal medulla are also likely to project ascending axons and may relay information from the adrenal medulla to the CNS [26], [27]. The nature of the immunolabelling pattern of the adrenal medulla of BSE infected cattle [28] and scrapie infected sheep [29] indicate that fine preganglionic sympathetic nerve processes may accumulate PrP d . There remain two possible routes by which the adrenal medulla may become infected following natural infection.…”