Page 67 - The autoimmune hypothesis of narcolepsy and its unexplored clinical features M.S. Schinkelshoek

appropriate using the Benjamini-Hochberg procedure. P-values below 0.05 were considered to be statistically significant. All analyses were conducted using the IBM SPSS Statistics 25 software package. Additional analyses were performed to replicate findings of previous studies focusing on the immune cell composition in the peripheral blood of NT1 patients (Hartmann et al., 2016, Lecendreux et al., 2017, Lind et al., 2020, Moresco et al., 2018).
Results
Participant characteristics
Table 4.1 describes participant characteristics. Mass cytometry experiments were performed with PBMCs of NT1 patients and healthy controls. The current cohort consisted of 16 samples of NT1 patients with recent onset of disease (< 2 years), 10 samples of NT1 patients with disease onset more than 2 years before blood sampling, 8 samples of healthy controls that are DQB1*06:02-positive and 5 samples of healthy controls that are HLA-DQB1*06:02 negative.
Table 4.1. Participant characteristics.
N
Males (n)
Time from disease onset (years ± standard deviation)
Hcrt-1 < 110 pg/mL
Hcrt-1 < 200 pg/mL HLA-DQB1*06:02 positive (n)
NT1 < 2 years after disease onset
16
7
0.9 ± 0.5
6/7
7/7
13/13 (100%)
NT1 > 2 years after disease onset
10
2
4.1 ± 1.8
4/5
5/5
8/9 (99%)
HLA- matched control
8
4 NA
NA
NA
8/8 (100%)
Non-HLA- matched control
5
1 NA
NA
NA
0/5 (100%)
Immune cell composition in peripheral blood
Hcrt-1 = hypocretin-1; HLA = human leukocyte antigen; NA = not applicable; NT1 = narcolepsy type 1.
Major immune cell lineages
39 immune cell markers were analyzed by mass cytometry in single immune cell suspensions of NT1 patients and healthy controls. The composition of the immune system deciphered using HSNE analysis in Cytosplore on all live, CD45+ cells (a total of 18.9 x 106 cells). Density features of the HSNE-embedded landmarks derived from unsupervised GMS clustering separated seven clusters that corresponded with seven major immune cell lineages: naïve (CD45RO- CD3+CD4+CD7+CCR7+) and memory (CD45RO+CD3+CD4+CD7+) CD4+
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