Fig. 3
From: A non-conserved amino acid variant regulates differential signalling between human and mouse CD28
P212 residue within the C-terminal proline-rich motif (YQPP212) of human CD28 is essential for CD28-mediated upregulation of pro-inflammatory cytokines. a Amino acid sequence of human (hCD28) and mouse CD28 WT (mCD28) and mutants. The substitution P212A in hCD28 is indicated in bold. b, c FACS analysis of CD28-negative CH7C17 Jurkat T cell line (b), or CH7C17 cells expressing hCD28WT or hCD28P212A mutant (c) stained with phycoerythrin (PE)-conjugated isotype control (Iso) or anti-CD28 (CD28-PE) Abs. d–g CH7C17 cells expressing CD28WT or hCD28P212A mutant were stimulated with 2 μg ml−1 crosslinked ANC28.1 (d–f) or CD28.2 Abs (g). TNF (d), IL-2 (e), and IL-8 (f, g) mRNA levels were measured by real-time PCR and values, normalised to GAPDH, were expressed as fold inductions (F.I.) over the basal level of cells stimulated with control Ig. Bars show the mean ± SD of one experiment representative of three. Statistical significance was calculated by Student’s t-test. *p < 0.05, **p < 0.01
