2A). CTLs only recognized DCs loaded with cognate-peptides (lysis: W248 (n = 3): 15.4 ± 2.9%; T368 (n = 2, #4 + 6): 47.9 ± 10.0%; K1234 (n = 2, #4 + 6): 28.5 ± 14.7%; P < 0.024 to P < 0.026, Wilcoxon-test), whereas they did not lyse naïve DCs (W248: 2.3 ± 1.2%; T368: 9.1 ± 12.8%; K1234: 1.7 ± 2.4%) and autologous-monocytes (W248: 1.0 ± 2.1%; T368: 0%; K1234: 7.3 ± 3.6%). Parallel, canine-IFN-γ-ELISPOT assays (E:T = 40:1; Fig. 2B) were performed using the same target cells. There, UTY-specific CTLs generated from healthy female dogs recognized hUTY-peptide-loaded-DCs
with 281–3106 specific-spots/100,000 T cells (median: 900/100,000; P < 0.042, Wilcoxon-test). Control cells, i.e. unpulsed-autologous DCs and monocytes, were not recognized (0–55/100,000 T cells, median: 19/100,000; P < 0.024 to P < 0.026, Wilcoxon-test). W248-specific-CTLs
reacted with UTY-loaded-autologous BMN 673 mw DCs within a range of 280–540/100,000 T cells (median: 392), T368-specific-CTLs with 2807–3106/100,000 T cells (median: 2957) and K1234-specific T cells with 900–965/100,000 IFN-γ-secreting T cells (median: 932). Unloaded autologous-DCs and monocytes were not recognized or only at background-levels (W248: 2–55/100,000, median: 19; T368: monocytes: 12–55/100,000, median: 34; K1234: 0–12/100,000, median: 6). We wanted to generate cUTY-specific T cells, characterize their functional-repertoire and their Y-restriction to possibly increase GvL-specificity by investigating Erismodegib datasheet DLA-identical male-cells: T cells from six female dogs
(#1, #4, #6, #9, #11, #14) were expanded using autologous-female DCs pulsed with the hUTY-derived peptides W248, T368 and K1234. We evaluated the ability of the in vitro induced female CTLs to recognize male-DLA-identical cells via hUTY-peptides (UTY-specific-reactivity) in IFN-γ-ELISPOT assays: female T cells were investigated in the presence of T2-cells (Table 2) and different target cells from the autologous-female-dogs, Monoiodotyrosine DLA-identical females and DLA-identical male-dogs (BM, DCs, monocytes, B cells, PBMCs and peptide-loaded-DCs, Fig. 3). UTY-specific-CTL reactivity was only detected in 50% of dogs tested (3/6: #1, #4, #6). Accordingly, T cell/target cell combinations of autologous-female-dogs, DLA-identical-females and DLA-identical-male-dogs were tested (#1/#2/#3; #4/#6/#5; #6/#4/#7; Table 1). To demonstrate, whether the hUTY-peptides are presented via MHC-I and whether these antigens could be specifically recognized by CTLs, peptides were loaded on hT2-cells, and CTL-reactivity was monitored with and without a canine-cross-reactive MHC-I-blocking antibody. CTLs could specifically, i.e. in an MHC-I-restricted-fashion, recognize peptide-loaded hT2-cells as shown in Table 2 (E:T = 40:1; W248-CTLs: 65–23/100,000 T cells,