Page 51 - The autoimmune hypothesis of narcolepsy and its unexplored clinical features M.S. Schinkelshoek

Figure 3.1. HLA-DQ6 presenting H1N1-HA275-287, Hcrt56-68 and Hcrt87-99 peptides show structural homology. A. H1N1-HA275-287 peptide. B. Hcrt56-68 peptide. C. Hcrt87-99 peptide. D. Overlay A., B. and C.
HA = hemagglutinin; Hcrt = hypocretin.
HLA-DQ6-H1N1-HA275-287-specific CD4+ T cells are readily detectable in NT1 patients and healthy controls, but do not cross-react with HLA-DQ6-Hcrt56-68 or -Hcrt87-99
T cell lines were generated from PBMCs of NT1 patients and healthy controls by co-culture with a pool of the H1N1-HA275-287, Hcrt56-68 and Hcrt87-99 peptides for 5 days followed by expansion in culture medium containing IL-2 and IL-15. Subsequently, the specificity of these T cell lines against the H1N1-HA275-287 peptide was determined by co-culture of the T cell lines with irradiated HLA- DQ6 positive allogeneic PBMCs in the presence or absence of the H1N1- HA275-287 peptide. Specific proliferation was measured by determining the incorporation of 3H-thymidine after three days of culture. Proliferation was defined as a stimulation index equal or higher to 3. All T cell lines proliferated in the positive control condition which reinforced our earlier conclusion based on visual assessing T cell lines that they were in good condition. In 28.4% (23/81) of NT1 patients and 15.8% (3/19) of healthy controls, an H1N1-HA275-
H1N1 reactivity in CD4+ T cells
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