Overexpression of IL-1ra gene up-regulates interleukin-1beta converting enzyme (ICE) gene expression: possible mechanism underlying IL-1beta-resistance of cancer cells

A bioartificial liver device secreting interleukin-1 receptor antagonist for the treatment of hepatic failure in rats

BACKGROUND

Liver transplantation is the treatment of choice for many patients with fulminant hepatic failure (FHF). A major limitation of this treatment is the lack of available donors. An optimally functioning bio-artificial liver (BAL) device has the potential to provide critical hepatic support to patients with FHF. In this study, we examined the efficacy of combining interleukin-1 (IL-1) receptor blockade with the synthetic function of hepatocytes in a BAL device for the treatment of FHF.

MATERIALS AND METHODS

We injected an adenoviral vector encoding human IL-1 receptor antagonist (AdIL-1Ra) into the liver of D-galactosamine (GalN) intoxicated rats via the portal vein. We also transfected primary rat hepatocytes and reversibly immortalized human hepatocytes (TTNT cells) with AdIL-1Ra, and incorporated these transfected hepatocytes into our flat-plate BAL device and evaluated their efficacy in our GalN-induced FHF rat model after 10 h of extracorporeal perfusion.

RESULTS

Rats injected with AdIL-1Ra showed significant reductions in the plasma levels of hepatic enzymes. Primary rat hepatocytes transfected with AdIL-1Ra secreted IL-1Ra without losing their original synthetic function. Incorporating these cells into the BAL device and testing in a GalN-induced FHF rat model resulted in significant reductions in plasma IL-6 levels and significantly improved animal survival. Incorporating the AdIL-1Ra transfected TTNT cells in the BAL device and testing in the GalN-induced FHF rat model resulted in significantly reduced plasma IL-6 levels, and a trend toward improved survival was seen.

CONCLUSION

Hepatocytes producing IL-1Ra are a promising cell source for BAL devices in the treatment of GalN-induced FHF.

Treatment of fulminant hepatic failure in rats using a bioartificial liver device containing porcine hepatocytes producing interleukin-1 receptor antagonist

Fulminant hepatic failure (FHF) is a serious clinical condition that is associated with high mortality. There is evidence that FHF is an inflammatory disease, which is supported clinically by elevated serum levels of cytokines. In an effort to develop hepatocytes with additional functions for use in our bioartificial liver (BAL) device, we focused on interleukin-1 (IL-1) blockade as a therapeutic modality. Primary porcine hepatocytes were isolated from the livers of miniature swine and then transfected with an adenoviral vector encoding human interleukin-1 receptor antagonist (AdIL-1Ra). The transfected hepatocytes secreted human IL-1Ra. These transfected hepatocytes were incorporated into a flat-plate BAL device to evaluate their efficacy in treating D-galactosamine (GalN)- induced FHF in a rat model. After extracorporeal perfusion with the BAL device containing the transfected hepatocytes, there were significant reductions in the plasma levels of hepatic enzymes (aspartate aminotransferase and alanine aminotransferase) and cytokines (IL-1 and IL-6), indicating a beneficial effect. Animal survival was significantly improved in the treated group compared to the control group. These experiments demonstrate that combining inflammatory cytokine blockade with a functional BAL device may be an effective therapeutic option in the treatment of FHF.

Staurosporine-induced apoptosis and hydrogen peroxide-induced necrosis in two human breast cell lines

The use of apoptosis-inducing agents in the treatment of malignant cancer is increasingly being considered as a therapeutic approach. In this study, the induction of apoptosis and necrosis was examined in terms of temporal dose responses, comparing a malignant and nonmalignant breast cell line. Staurosporine (SSP)-induced apoptosis and H(2)O(2)-induced necrosis were evaluated by two cytotoxicity assays, neutral red (NR) and methyl-thiazolyl tertrazolium (MTT), in comparison with a differential dye uptake assay, using Hoechst33342/propidium iodide (Hoechst/PI). Confirmatory morphological assessment was also performed by routine resin histology and transmission electron microscopy. Cell viability was assessed over a 0.5-48 h time course. In nonmalignant HBL-100 cells, 50 nM SSP induced 100% apoptosis after a 48 h exposure, while the same exposure to SSP caused only 4% apoptosis in metastatic T47D cells. Although complete apoptosis of both cell lines was induced by 50 microM SSP, this effect was delayed in T47D (24 h) compared with HBL-100 (4 h). Results also showed that neither MTT or NR can distinguish between the modes of cell death, nor detect the early onset of apoptosis revealed by Hoechst/PI.

Transfer of the interleukin-1 receptor antagonist gene into rat liver abrogates hepatic ischemia-reperfusion injury

BACKGROUND

The anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1Ra) is known to reduce hepatic ischemia-reperfusion injury. Therefore, we wished to examine the effect of IL-1Ra gene delivery into the rat liver on hepatic ischemia-reperfusion injury.

METHODS

IL-1Ra cDNA was delivered into the rat liver by a single injection of the transgene vector into the portal vein using either the plasmid-cationic liposome or the recombinant adenoviral vector. At 24 hours after the gene delivery, rats were subjected to partial liver ischemia for 90 minutes followed by reperfusion. Liver tissue and serum samples were taken at 180 minutes of reperfusion, and the degree of the liver injury as well as the expression level of pro-inflammatory cytokines in the serum and tissue were investigated. In addition, we assessed the effect of IL-1Ra gene delivery on the 7-day survival rate when the nonischemic liver lobe was partially excised immediately following reperfusion.

RESULTS

In both cases of delivery methods, gene transfer of IL-1Ra resulted in significant elevation of serum IL-1Ra concentration, which reached maximal levels at 24 hours following the delivery. However, the highest serum concentration with the adenoviral vector was 1,000-fold of that in the liposome-treated animals. In the IL-1Ra delivered rats, liver damage, as well as production of pro-inflammatory cytokines, at 180 minutes of reperfusion was significantly reduced in a concentration-dependent manner of the circulating IL-1Ra protein. Rats subjected to the adenoviral vector gene delivery had higher 7-day survival rates compared with control animals.

CONCLUSIONS

IL-1Ra gene delivery into the liver may be of therapeutic use for abrogating hepatic ischemia-reperfusion injury after transplantation.

Higher frequency of allele 2 of the interleukin-1 receptor antagonist gene in patients with juvenile idiopathic arthritis

OBJECTIVE

An increased incidence of allele 2 of the interleukin-1 receptor antagonist gene (IL1RN*2) in several inflammatory diseases has recently been reported. The aim of this study was to examine a variable number tandem repeat (VNTR) polymorphism of the IL1RN gene in patients with juvenile idiopathic arthritis (JIA).

METHODS

Findings in 185 Czech patients with JIA were compared with those in 168 Czech controls, 50 JIA patients and 52 controls of Turkish origin, and 79 controls from central England. VNTR polymorphism analysis of IL1RN was performed by polymerase chain reaction using 2 flanking primers to amplify an 86-bp tandem repeat region in intron 2.

RESULTS

The frequency and carriage rate of IL1RN*2 were significantly increased in Czech JIA patients compared with the Czech controls (frequency 27.6% versus 15.8%; carriage rate 44.3% versus 26.2%). Increased frequency and carriage rate of IL1RN*2 were found in 23.3% and 40.0% of Turkish JIA patients and in 17.3% and 34.6% of ethnically matched controls. The high representation of IL1RN*2 in 52.3% of the 22 patients with extended oligoarthritis, 31.3% of the 56 patients with enthesitis-related arthritis, and 42.9% of the 14 patients with other arthritis was particularly responsible for the increased frequency of IL1RN*2 in the Czech JIA patients. We found no association of IL1RN*2 with disease activity or severity parameters.

CONCLUSION

Inheritance of IL1RN*2 may contribute to genetic susceptibility in several forms of autoimmune diseases, including JIA. The IL1RN*2 allele may be useful as a prognostic indicator of the evolution of an extended oligoarticular course of JIA.