HISTOLOGICAL MARKERS IN NASAL-MUCOSA OF PATIENTS WITH ALZHEIMERS-DISEASE

Neuropathological changes such as dystrophic neurites and the presence of abnormal tau protein in the olfactory system, including primary se nsory cells and nerve fibres have previously been demonstrated in nasa l mucosa tissue of patients with Alzheimer's disease (AD). These chang es were detected in autopsy-derived material from histopathologically confirmed AD cases as well as in biopsy tissue from clinical severely ill AD patients. To investigate the potential usefulness for the early diagnosis of AD, we obtained biopsy tissue from olfactory mucosa from 5 clinically mild to moderate AD patients and stained for the presenc e of tau or beta-amyloid by immunocytochemistry using a panel of speci fic antibodies. No positive staining was found in any of the cases. Fo r comparison, post-mortem olfactory tissue from AD patients with sever e neuropathological changes (widespread neurofibrillary tangles and am yloid in the brain) was investigated, in these severe cases, tau immun oreactivity was found in fine nerve fibres in the lamina propria and i n a few olfactory epithelial cells. These results are consistent with other reports showing that cytoskeletal changes and tau pathology in t he olfactory epithelium are not primary (or specific) features of AD a nd may occur predominantly in late stages of the disease.