In addition, we confirmed that SDF-1 could amplify the role of EX-4 in regulating various signaling pathways, such as type II diabetes mellitus, the insulin signaling pathway, and the allograft rejection pathway (Fig. 6D and Table S9), while EX-4 could aggravate the effect of SDF-1 on PDLSC biological roles by regulating signaling pathways, including primary immunodeficiency, tight junction, and basal transcription factors (Fig. 6E and Table S9). The gene discussed is CXCL12; the disease is type 2 diabetes mellitus.