A new era for innate immunity

Pigeon TBK1 is involved in antiviral innate immunity by mediating IFN activation

TANK-binding kinase 1 (TBK1), a noncanonical member of the inhibitor-kappaB kinases (IKKs) family, plays a vital role in regulating type-I interferon (IFN) production in mammals and birds. We cloned pigeon TBK1 (PiTBK1) and conducted bioinformatics analyses to compare the protein homology of TBK1 from different species. Overexpression of PiTBK1 in DF-1 cells induced the activation of IFN-β, and this activation positively correlated with the dosage of transfected PiTBK1 plasmids. In pigeon embryonic fibroblasts (PEFs) cells, it does the same. And the STK and Ubl domain are essential for IFN-β activation. Consistent with the previous results, when PiTBK1 expressed more, NDV replication was lower. Our results suggest that PiTBK1 is an important regulator of IFNs and plays a pivotal role in antiviral innate immunity in pigeon.

Ascites regression and survival increase in mice bearing advanced-stage human ovarian carcinomas and repeatedly treated intraperitoneally with CpG-ODN

Tumor cell growth, even in advanced stages of ovarian cancer, is nearly always restricted to the peritoneal cavity; therefore, repeated intraperitoneal injections of oligodeoxynucleotides containing dinucleotides with unmethylated CpG motifs (CpG-ODN) recruiting and activating innate effector cells throughout the abdominal cavity to the tumor site might control tumor cell growth and ascites formation. After a single CpG-ODN treatment, in IGROV-1 ovarian tumor ascites-bearing athymic mice, the number of tumor cells declined rapidly and markedly, and ascites volumes declined shortly after treatment (5 h), increasing thereafter at a slower rate than in controls. When administered every 7 days for 4 weeks, CpG-ODN had only a marginal effect on survival time, whereas administration 5 days/wk for 3 or 4 weeks led to a significantly increased survival time as compared with controls (P<0.005) and completely controlled ascites growth without apparent toxicity, although a disorganization of lymphoid organs was observed. Bio-plex assay of cytokine levels in peritoneal fluid of ascites-bearing mice after CpG-ODN treatment revealed an increase in interleukin (IL)-6, IL-10, IL-12, and interferon-gamma at 24 hours, which returned to control mice levels at 48 to 96 hours, whereas the high levels of angiogenic factors remained unchanged. Depletion of natural killer or monocytes/macrophages only slightly influenced the CpG-ODN-induced reduction of ascites tumor cells, indicating that the antitumor activity might not be related to a specific cell/cytokine but rather to the repertoire of cells and cytokines accumulated in the peritoneal cavity. Thus, our data suggest a relevant role for repeated activation of cells and cytokines of innate immunity in the therapy of ovarian cancer patients with malignant ascites.