FIGURE 3.

Effect of Siglec-5 overexpression on TCR-induced transcription factor activities. (a) Sequence alignment of the ITIM and ITSM domains of PD-1 and Siglec-5, −7 and −9. Shared protein motifs are highlighted in red, and conserved amino acids are highlighted in blue. (b) and (c) Jurkat T cells were transiently transfected with NFAT or AP-1 luciferase reporter vectors, along with (a) full length Siglec-5 or (b) truncated Siglec-5 (lacking ITIM and ITSM domains). 4hrs post anti-CD3 stimulation, NFAT and AP-1 luciferase activity was measured. Relative luciferase activity was calculated based on Renilla luciferase activity. Representative figures of three independent experiments. Statistical analysis: 2wayANOVA, Tukey’s multiple comparison test, *** p < 0·001, **** p < 0·0001