Objective: To explore the changes of inflammation cytokines during acute renal transplantation rejection and decipher the functions of their protein-protein interaction network.

Methods: Serum samples were collected from renal transplantation patients with stable renal function or acute rejection (n = 6 each) to measure the expression level of 40 inflammatory factors by APIX protein array. The differentially expressed proteins were selected and their protein-protein interaction networks constructed. And biologic processes were analyzed by the online tools of String and Network Ontology Analysis.

Results: There were 8 differentially expressed cytokines in the AR group versus the stable group (M (Q(1)-Q(3)), CCL24: 700 (255 - 1157) vs 330 (100 - 610) ng/L, ICAM-1: 58 737 (8018 - 105 395) vs 22 660 (137 - 68 914) ng/L, IL-10: 120 (20 - 517) vs 298 (81 - 11 609) ng/L, IL-6sR: 11 328 (3357 - 21 251) vs 7665 (370 - 12 455) ng/L, CCL3: 1712(7002 - 32 634) vs 283 (54 - 1915) ng/L, CCL4: 554 (28 - 2355) vs 283(104 - 1915) ng/L, TIMP-1: 15 560 (13 343 - 42 481) vs 11 271 (1207 - 18 228) ng/L, CCL5: 44 547 (38 252 - 78 631) vs 27 765 (12 073 - 46 627) ng/L, all P < 0.05). The analyses of protein-protein association network showed that these proteins were correlated and involved in such biological processes as taxis, chemotaxis, inflammatory reactions, wound responses and leukocytic migration.

Conclusions: Comparing the inter-group differences of inflammatory cytokines and further developing and analyzing the protein-protein interaction network may help us to explore the mechanisms of acute renal transplantation rejection. And the differential cytokines can be used as candidate diagnostic biomarkers and intervention targets.