Evaluation of a simultaneous adsorption device for cytokines and platelet-neutrophil complexes in vitro and in a rabbit acute lung injury model.

BACKGROUND: Platelet-neutrophil complexes (PNCs) readily migrate into tissues and induce tissue damage via cytokine or other pathogenic factors release. These actions are involved in onset and progression of acute respiratory distress syndrome (ARDS). Thus, simultaneous removal of cytokines and activated neutrophils, including PNCs by blood purification may prevent development of ARDS and enhance drug effects. The goal of this study was to examine the effect of a newly developed adsorption column (NOA-001) that eliminates cytokines and activated neutrophils in a lung injury model. RESULTS: Adsorption of cytokines, such as IL-8, IL-6 and HMGB-1, and PNCs was first measured in vitro. Lung injury was induced by HCl and lipopolysaccharide intratracheal infusion in rabbits ventilated at a low tidal volume (7-8 mL/kg) and PEEP (2.5 cmH2O) for lung protection. Arterial blood gas, hematologic values, plasma IL-8, blood pressure and heart rate were measured, and lung damage was evaluated histopathologically in animals treated with 8-h direct hemoperfusion with or without use of NOA-001. The in vitro adsorption rates for IL-8, IL-6, HMGB-1, activated granulocytes and PNCs were 99.5 (99.4-99.5)%, 63.9 (63.4-63.9)%, 57.6 (57.4-62.1)%, 9.9 (-4.4-21.3)% and 60.9 (49.0-67.6)%, respectively. Absorption of PNCs onto fibers was confirmed microscopically. These adsorption effects were associated with several improvements in the rabbit model. In respiratory function, the PaO2/FIO2 ratios at 8 h were 314 ± 55 mmHg in the NOA-001 group and 134 ± 41 mmHg in the sham group. The oxygenation index and PaCO2 at 8 h were 9.6 ± 3.1 and 57.0 ± 9.6 mmHg in the sham group and 3.0 ± 0.8 and 40.4 ± 4.5 mmHg in the NOA-001 group, respectively (p < 0.05). Blood pH at 8 h reached 7.18 ± 0.06 in the sham group, but was maintained at 7.36 ± 0.03 (within the normal range) in the NOA-001 group (p < 0.05). In lung histopathology, fewer hyaline membrane and inflammatory cells were observed in the NOA-001 group. CONCLUSION: A column for simultaneous removal of cytokines and PNCs showed efficacy for improvement of pulmonary function in an animal model. This column may be effective in support of treatment of ARDS.

Transcriptional repression of p27 is essential for murine embryonic development.

The Nczf gene has been identified as one of Ncx target genes and encodes a novel KRAB zinc-finger protein, which functions as a sequence specific transcriptional repressor. In order to elucidate Nczf functions, we generated Nczf knockout (Nczf-/-) mice. Nczf-/- mice died around embryonic day 8.5 (E8.5) with small body size and impairment of axial rotation. Histopathological analysis revealed that the cell number decreased and pyknotic cells were occasionally observed. We examined the expression of cell cycle related genes in Nczf-/- mice. p27 expression was increased in E8.0 Nczf-/- mice compared to that of wild type mice. Nczf knockdown by siRNA resulted in increased expression of p27 in mouse embryonic fibroblasts (MEFs). Furthermore, p27 promoter luciferase reporter gene analysis confirmed the regulation of p27 mRNA expression by Nczf. Nczf-/-; p27-/- double knockout mice survived until E11.5 and the defect of axial rotation was restored. These data suggest that p27 repression by Nczf is essential in the developing embryo.

Anti-interferon-α neutralizing antibody induced telaprevir resistance under the interferon-α plus telaprevir treatment in vitro.

Although the development of anti-interferon (IFN)-α neutralizing antibodies (NAbs) is likely to be a common clinical problem for patients with various diseases treated with IFN, anti-IFN-α NAb has been exceptionally considered to have no clinical significance in the treatment of chronic hepatitis C with pegylated IFN-α (Peg-IFN-α). However, we recently clarified that the presence of NAb was associated with a non-response to the Peg-IFN plus ribavirin (RBV) therapy. In this study, we used the HCV-replicon system with genotype 1b, and investigated the role of anti-IFN-α NAb in the response to telaprevir (TVR)-containing new antiviral therapy for hepatitis C virus (HCV). Anti-IFN-α NAb-positive sera specifically inhibited the anti-HCV effects of IFN-α, without any effect on the activity of IFN-ß in vitro. The NAb-positive sera also inhibited the IFN-α-dependent induction of interferon-stimulated genes, MxA and OAS-1, in a dose-dependent manner. Although TVR monotherapy decreased the HCV-RNA in vitro, the HCV-RNA was increased again with the development of TVR-resistant mutations. When IFN-α was administrated with TVR, the replication of HCV was continuously suppressed for more than a month. However, in the presence of anti-IFN-α NAb-positive sera, even when IFN-α was combined with TVR, the levels of HCV-RNA exhibited a time-course similar to that with TVR monotherapy, and HCV with TVR-resistant mutations emerged. In conclusion, our findings suggest that the presence of IFN-α NAb decreases the antiviral effects of IFN-α and may be related to the development of TVR-resistant mutated viruses.