Kallikrein-related peptidases 6 and 10 are elevated in cerebrospinal fluid of patients with Alzheimer’s disease and associated with CSF-TAU and FDG-PET

Table 1 Characteristics of participants

Variables	AD N = 32	NC N = 23	p values
global CDR frequency 0/0.5/1/2/3	0 / 24 / 7 / 1 / 0	23 / 0 / 0 / 0 / 0	< 0.001
CDR-SOB mean ± SD (range)	3.5 ± 1.84 (0.5–9)	0.0 ± 0.00 (0.0–0.0)	< 0.001
MMSE score mean ± SD (range)	23.6 ± 4.37 (9–29) n = 31	29.5 ± 0.79 (28–30)	< 0.001
Sex male / female	14 / 18	18 / 5	0.011
Age in years mean ± SD (range)	71.5 ± 4.70 (61–82)	64.7 ± 9.16 (50–85)	0.002
ApoE ε4 allele frequency 0/1/2/n.a.	9 / 15 / 4 / 4	15 / 8 / 0	0.010
CSF-Aβ₄₂ levels [ng/l] mean ± SD (range)	516 ± 145.6 (260–930)	1014 ± 199.0 (668–1354)	< 0.001*
Aβ₄₂/Aβ₄₀ ratios mean ± SD (range)	0.040 ± 0.0094 (0.020–0.061)	0.067 ± 0.0096 (0.051–0.0813)	< 0.001*
CSF t-tau levels [ng/l] mean ± SD (range)	588 ± 334 (166–1650)	182 ± 41.3 (108–266)	< 0.001*
CSF p-tau levels [ng/l] mean ± SD (range)	74.8 ± 32.5 (36–176)	35.5 ± 7.48 (23–53)	0.001*
CSF-KLK6 ng/ml mean ± SD (range)	321 ± 115.8 (132–663)	220 ± 62.4 (101–344)	< 0.001*
CSF-KLK8 ng/ml mean ± SD (range)	0.163 ± 0.026 (0.12–0.22)	0.157 ± 0.0580 (0.10–0.37)	0.637*
CSF-KLK10 ng/ml mean ± SD (range)	0.665 ± 0.2338 (0.22–1.11)	0.484 ± 0.0249 (0.08–0.95)	0.008*

p values: results of Mann-Whitney-U test or (*) t-test, respectively. In five patients, CDR was rated due to doctor’s letter, and one patient underwent the Montreal Cognitive Assessment test (MOCA test) instead of the MMSE
AD patients with Alzheimer’s disease, NC cognitively normal controls, SD standard deviation, CDR clinical dementia rating scale, SOB sum of boxes, GLO global, MMSE Mini-Mental State Examination, ApoE Apolipoprotein E, CSF cerebrospinal fluid, Aβ β-amyloid, KLK kallikrein related peptidase

ISSN: 2047-9158