Page 73 - The autoimmune hypothesis of narcolepsy and its unexplored clinical features M.S. Schinkelshoek

All NT1 patients vs HLA-matched controls
Since differences between patient groups were less pronounced than those between NT1 patients with recent disease onset and HLA-matched controls, we assessed differences between NT1 patients and HLA-matched controls once again, but this time for all NT1 patients, regardless of time from disease onset. Interestingly, all but one of the immune cell populations described in Figure 4.4 and Supplementary table 4.2 remained significant or differences became even more outspoken (Supplementary table 4.4).
Discussion
We describe an unbiased mass cytometry-based approach to identify immune cell clusters that are enriched in NT1 patients compared to HLA-matched healthy controls. While differences in major immune cell lineages were absent in our sample, we show that several populations of memory CD4+ T cells and one population of CD8+ T cells were more frequently found in NT1 patients than in healthy HLA-DQB1*06:02-matched controls. Additionally, we show that differences in immune cell composition between NT1 patients with recent disease onset and those longer after disease onset were limited. This finding is supported by the fact that most populations discovered in the comparison between NT1 patients with recent disease onset and HLA-matched controls remained significantly different when comparing all NT1 patients with HLA- matched controls.
These results build upon the findings of other studies that have compared the composition of the immune system in NT1 with that of healthy controls using flow cytometry in which a global T cell activation in peripheral blood of NT1 patients (Lecendreux et al., 2017, Moresco et al., 2018) and an even stronger T cell activation was seen in the cerebrospinal fluid compared with healthy controls (Moresco et al., 2018). Moresco et al. further describe more central memory (CD45RO+CCR7+), more naïve (CD45RA+CCR7+), less effector memory (CD45RO+CCR7-) CD4+ T cells and more CD3-CD56+ cells in NT1 patients. We only replicated a non-significant higher frequency of the latter in recent onset NT1 patients compared to healthy controls. Another study on the immune cell composition in the peripheral blood of NT1
Immune cell composition in peripheral blood
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