TYRP1 and Alzheimer disease: In contrast to free plasma CatB, plasma-EV-CatB levels were significantly increased in A+T−N− compared with A−T−N− (A−T−N−, 143.3 ± 40.4 pg/ml; A+T−N−, 177.7 ± 52.6 pg/ml; P = 0.042) but not in the other AD continuum groups (Fig. 4A).