Figure 4.
Identification of CD4+ T-cell frequencies directed against native and citGRP78 peptides in healthy control (HC) subjects and patients with type 1 diabetes (T1D) analyzed by ex vivo Tmr assays. A–H: In HC subjects and patients with T1D, respectively, representative FACS plots depict CD4+ T cells in the enriched fraction directed against the native GRP78 peptide 498–512R (A and B), against the citGRP78 peptide 498–512X (C and D), against the native GRP78 peptide 195–209R (E and F), and against the citGRP78 peptide 195–209X (G and H). I–L: Total CD4+ T-cell frequencies in the enriched fraction directed against 498–512R (I), 498–512X (J), 195–209R (K), and 195–209X (L) in HC subjects (n = 8; ■) and in patients with T1D (n = 15) subdivided by new-onset T1D (<1 year; n = 4; △) and long-standing T1D (≥1 year; n = 11; ●). CD4+ T-cell frequencies >5 Tmr+ cells/106 (dashed line) are considered positive (indicated in red). M–P: Total CD4+ T-cell frequencies in the enriched fraction comparing the native and citrullinated forms of peptide 498–512 in HC subjects (M) and patients in T1D (N) and of peptide 195–209 in HC subjects (O) and patients with T1D (P). Data in I–L are mean ± SD and were analyzed by Mann-Whitney U test. *P < 0.05. M–P data were analyzed using the Wilcoxon rank sum test. APC, allophycocyanin.