Role and mechanism of platelet-derived growth factor BB in thrombocytosis in Kawasaki disease / 中国当代儿科杂志

OBJECTIVES@#To study the role and mechanism of platelet-derived growth factor BB (PDGF-BB) on platelet production in Kawasaki disease (KD) mice and human megakaryocytic Dami cells through in vitro and invivo experiments.@*METHODS@#ELISA was used to measure the expression of PDGF in the serum of 40 children with KD and 40 healthy children. C57BL/6 mice were used to establish a model of KD and were then randomly divided into a normal group, a KD group, and an imatinib group (30 mice in each group). Routine blood test was performed for each group, and the expression of PDGF-BB, megakaryocyte colony forming unit (CFU-MK), and the megakaryocyte marker CD41 were measured. CCK-8, flow cytometry, quantitative real-time PCR, and Western blot were used to analyze the role and mechanism of PDGF-BB in platelet production in Dami cells.@*RESULTS@#PDGF-BB was highly expressed in the serum of KD children (P<0.001). The KD group had a higher expression level of PDGF-BB in serum (P<0.05) and significant increases in the expression of CFU-MK and CD41 (P<0.001), and the imatinib group had significant reductions in the expression of CFU-MK and CD41 (P<0.001). In vitro experiments showed that PDGF-BB promoted Dami cell proliferation, platelet production, mRNA expression of PDGFR-β, and protein expression of p-Akt (P<0.05). Compared with the PDGF-BB group, the combination group (PDGF-BB 25 ng/mL + imatinib 20 μmol/L) had significantly lower levels of platelet production, mRNA expression of PDGFR-β, and protein expression of p-Akt (P<0.05).@*CONCLUSIONS@#PDGF-BB may promote megakaryocyte proliferation, differentiation, and platelet production by binding to PDGFR-β and activating the PI3K/Akt pathway, and the PDGFR-β inhibitor imatinib can reduce platelet production, which provides a new strategy for the treatment of thrombocytosis in KD.

Upregulation of proto-oncogene c-mpl by interleukin-13 in Dami cells / 中国病理生理杂志

AIM: To investigate the effects of recombinant human interleukin-13 (rhIL-13) on the expression of proto-oncogene c-mpl in Dami cells, a human megakaryobiastic leukemia cell line. METHODS: The expression of c-mpl mRNA in Dami cells was investigated with RT-PCR. The expression of membrane-bound protein c-mpl on Dami cells was investigated with ligand combination experiment. RESULTS: In RT-PCR experiment, we found the quantitis of expression of c-mpl mRNA in 25 ?g/L rhIL-13 group increased by 24.8%. In ligand combination experiment, we found quantitis of expression of membrane-bound protein c-mpl in 100 ?g/L rhIL-13 group increased by 28.5% ( P