D, E, F, G, H Experimental validation of the PPIs predicted on the basis of the high confidence CN shown in C. CD4+T cells were left unstimulated (-) or stimulated (+) with anti-CD3 and anti-CD4 antibodies and subsequently lysed. Equal amounts of cell lysates were incubated with isotype control (Iso Ctrl) or the specified antibodies and the resulting immunoprecipitates (IP) analyzed by immunoblot with the antibodies specified in the left margin. The validated PPIs predicted in C correspond to CSK-CBLB and CSK-CD5 (D), CRKL-PI3Kp85β and CSK- PI3Kp85β (E). Molecular masses are shown (kDa). Data are representative of at least 2 experiments. 