Profiles and predictive value of cytokines in children with human metapneumovirus pneumonia.

BACKGROUND: Human metapneumovirus (HMPV) is an important cause of respiratory tract infections in young children. Early innate immune response to HMPV is focused on induction of antiviral interferons (IFNs) and other pro-inflammatory cytokines that are critical for the formation of adaptive immune responses. To evaluate the predictive value of Th1/Th2 cytokines which include IL-2, IL-4, IL-6, IL-10, INF-γ and TNF-α in pneumonia caused by HMPV. METHODS: A retrospective study was performed among 59 pneumonia pediatric patients with HMPV infection and 33 healthy children as the control cohort, which was detected by the immunofluorescence assay, and the Th1/Th2 cytokines were measured by flow cytometry. 131 children infected with Influenza virus A (IVA) and 41 children infected with influenza virus B (IVB) were detected by RT-PCR assay in throat swabs. RESULTS: When compared with the healthy children, children who were infected with HMPV pneumonia had a significantly lower level of IL-2 (p < 0.001) and higher levels of IL-4 (p < 0.001), IL-6 (p = 0.001), IL-10 (p < 0.001), and IFN-γ (p < 0.001). Compared with patients diagnosed with IVA or IVB infection, HMPV-positive patients had significantly higher levels of IL-4 (p < 0.001 and < 0.001), IFN-γ (p < 0.001 and < 0.001), and TNF-α (p < 0.001 and 0.016). Moreover, compared with IVA patients, HMPV-positive patients had a significantly lower level of IL-6 (p = 0.033). Finally, when comparing cytokine levels among the patients with HMPV pneumonia, IL-6 and TNF-α levels were found to be significantly higher in the severe group than the mild group (p = 0.027 and 0.049). The IL-6 and TNF-α were used to differentiate between mild symptoms and severe symptoms in children diagnosed with HMPV pneumonia with an AUC of 0.678 (95% CI 0.526-0.829) and 0.658 (95% CI 0.506-0.809), respectively. CONCLUSION: Our study indicated that difference in cytokine trends depending on the virus species. The levels of IL-4, TNF-α and IFN-γ were significantly distinguished in children infected with HMPV versus IVA and IVB. IL-6 and TNF-α may be helpful in assessing the severity and prognosis of HMPV infection.

Cytokine Gene Polymorphisms in Chinese Children with Idiopathic Nephrotic Syndrome.

BACKGROUND: Cytokines play a role in the progression of idiopathic-nephrotic syndrome (INS). OBJECTIVES: To investigate the association of different cytokine genes polymorphisms with INS incidence and response to steroid therapy in Chinese children. METHODS: 182 children with INS and 100 healthy controls were enrolled in this study. Blood genomic DNAs were used to analyze20 single nucleotide polymorphisms (SNPs) in 8 cytokine genes includingIL-21, IL-18, IL-6, IFN-γ, IL-4, IL-10, IL-17F, IL-17A d by multi-PCR with next-generation sequencing. RESULTS: Among 182 children with INS, 89 (48.6%) were steroid-sensitive (SS), 73 (39.9%) were steroid-dependent (SD) and 21 (11.5%) were steroid-resistant (SR). In 20 SNPs, IL-4-rs2243283 exhibited a significantly different genotype distribution between INS and the healthy controls (CC is a risk genotype: 66.5% of INS VS 51% of the control; OR=1.91, p=0.012). Patients carrying AG genotype (rs2275913, IL-17A) had a significantly higher risk of steroid-dependent response (69.1% of SD VS 46.4% of SS; OR=2.58, p=0.014). Similarly, patients carrying A allele of IL-10-rs1800872 (39.0% of SD VS 26.7% of SS; OR=1.76, p=0.018) and C allele of IL-10-rs1800896 (12.3% of SD VS 3.9% of SS; OR=3.44, p=0.004) had a higher risk of steroid-dependent response. However, none of these 20 SNPs showed a significant difference between SS group and SR group. CONCLUSION: Among the 20 cytokine gene SNPs, IL-4-rs2243283 might increase the susceptibility to INS in Chinese children; rs2275913 of IL-17A, rs1180972, and rs1800896 of IL-10 show association with the steroid -response in Chinese INS children.

Hepatitis B virus X protein stimulates IL-6 expression in hepatocytes via a MyD88-dependent pathway.

BACKGROUND & AIMS: Hepatitis B virus (HBV) X protein (HBx) has been implicated in HBV-associated carcinogenesis by activating signal transduction pathways and influencing gene transcription in liver cells. We aimed to investigate the underlying mechanisms for HBx-induced production of interleukin-6 (IL-6), one of the major inflammatory mediators that stimulate hepatocellular carcinoma development. METHODS: HBx was overexpressed in hepatic and hepatoma cell lines and IL-6 expression levels were measured by quantitative RT-PCR and ELISA. The activation of IRAK-1, ERKs/p38, and NF-κB was determined by Western blotting using specific anti-phosphoprotein antibodies. The role of MyD88 in these processes was analyzed by MyD88 RNAi and expression of an inactive MyD88 mutant. RESULTS: Expression of HBx in hepatic and hepatoma cells led to a dramatic enhancement of IL-6 synthesis and secretion. Dysfunction of MyD88 in these cells prevented the HBx-triggered IL-6 production. HBx expression also activated downstream signaling proteins of MyD88 including IRAK-1, ERKs/p38, and NF-κB. Inactivation of these signaling molecules blocked IL-6 synthesis as well. HBx-stimulated the expression of MyD88. CONCLUSIONS: In hepatocytes and hepatoma cells, HBx stimulates the production of IL-6 in a MyD88-dependent manner, indicating that parenchymal liver cells are an additional source of high levels of IL-6 in the HBV-infected liver microenvironment. HBx could be involved in HBV-mediated liver carcinogenesis, through this mechanism of action.

[Role of HBx in hepatocellular carcinoma development].

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in China, which is mainly caused by hepatitis B virus (HBV) infection. The X gene product (HBx) of HBV has extensive trans-activating functions. HBx affects the signal transduction, apoptotic cell death and cell cycle through interaction with variety intracellular proteins in infected hepatocytes. In view of the importance of HBx in HBV replication and in hepatic cell functions, the role of HBx in HCC development has been attracting great attention.