ABL Genomic Editing Sufficiently Abolishes Oncogenesis of Human Chronic Myeloid Leukemia Cells In Vitro and In Vivo.

Chronic myelogenous leukemia (CML) is the most common type of leukemia in adults, and more than 90% of CML patients harbor the abnormal Philadelphia chromosome (Ph) that encodes the BCR-ABL oncoprotein. Although the ABL kinase inhibitor (imatinib) has proven to be very effective in achieving high remission rates and improving prognosis, up to 33% of CML patients still cannot achieve an optimal response. Here, we used CRISPR/Cas9 to specifically target the BCR-ABL junction region in K562 cells, resulting in the inhibition of cancer cell growth and oncogenesis. Due to the variety of BCR-ABL junctions in CML patients, we utilized gene editing of the human ABL gene for clinical applications. Using the ABL gene-edited virus in K562 cells, we detected 41.2% indels in ABL sgRNA_2-infected cells. The ABL-edited cells reveled significant suppression of BCR-ABL protein expression and downstream signals, inhibiting cell growth and increasing cell apoptosis. Next, we introduced the ABL gene-edited virus into a systemic K562 leukemia xenograft mouse model, and bioluminescence imaging of the mice showed a significant reduction in the leukemia cell population in ABL-targeted mice, compared to the scramble sgRNA virus-injected mice. In CML cells from clinical samples, infection with the ABL gene-edited virus resulted in more than 30.9% indels and significant cancer cell death. Notably, no off-target effects or bone marrow cell suppression was found using the ABL gene-edited virus, ensuring both user safety and treatment efficacy. This study demonstrated the critical role of the ABL gene in maintaining CML cell survival and tumorigenicity in vitro and in vivo. ABL gene editing-based therapy might provide a potential strategy for imatinib-insensitive or resistant CML patients.

Inducible nitric oxide synthase inhibition influenced granuloma formation with suppressed collagen expression in myositis caused by Toxocara canis in mice.

The role of nitric oxide (NO) in granuloma pathology is largely unclear to date. We investigated the role of NO in fibrotic granuloma development in the musculature of mice infected with Toxocara canis from 1 day (dpi) to 8 weeks post-infection (wpi) using the NO synthase (NOS) inhibitors, L-NIL (l-N6-1-iminoethyl lysine). In infected mice, elevated serum NO concentrations were seen at 1 dpi (204.1 +/- 0.2 microM) and 1 wpi (145.1 +/- 0.2 microM); it declined drastically from 4 wpi onwards (57.0 +/- 0.1 microM). In L-NIL-treated mice, the NO concentration was drastically reduced from 15% during 1 wpi; thereafter, it was restored to almost half that in infected mice. Inducible NOS expression was enhanced in infected and L-NIL-treated mice at 4 wpi but declined at 8 wpi as assessed by immunohistochemistry. L-NIL treatment resulted in large, irregularly shaped granulomas with suppressed collagen contents at 4 wpi but not at 8 wpi. The suppressed collagen contents might have been related to decreased serum NO and Th2-type cytokine of interleukin-4 but not Th1-type cytokine of interferon-gamma expression.

Aberrant activation of the TNF-alpha system and production of Fas and scavenger receptors on monocytes in patients with end-stage renal disease.

Ten patients with nondialyzed chronic renal failure (CRF), 14 receiving continuous ambulatory peritoneal dialysis (CAPD), 16 receiving hemodialysis (HD), and 10 normal controls (NC), were evaluated. Levels of Fas antigen (CD95), scavenger receptors (CD36 and CD68), and tumor necrosis factor-receptor 2 (CD120b) on monocytes were measured using flow cytometry. All patients showed lymphocytopenia, and monocyte counts were decreased in those with CRF. Fas levels were higher in patients receiving HD than the others, and were higher in the CRF and CAPD groups than in controls. CD120b levels were similar to those of Fas. Monocyte CD36 levels in the dialysis groups were significantly higher than in the CRF and NC groups. CD68 was also significantly elevated in HD patients. Fas levels were positively correlated with those of CD120b and CD68. The patient groups showed higher levels of apoptotic markers and scavenger receptors, combined with activation of the TNF-alpha system, especially in patients receiving HD.

Prevalence of antibody to hepatitis E virus among haemodialysis patients in Taiwan: possible infection by blood transfusion.

BACKGROUND/AIMS: A higher prevalence of anti-hepatitis E virus (HEV) in non-endemic viral hepatitis such as in Germany has been reported in our previous study. The aim of this study was to assess the seroepidemiology of HEV among haemodialysis (HD) patients in Shin-Kong Hospital, Taiwan, and to evaluate whether there was an increased risk of infection and exposure to HEV even in an area of endemic viral hepatitis. METHODS: Serum samples obtained from 400 Taiwanese patients on chronic HD (group 1), 400 sex- and age-matched healthy subjects (group 2) and hospital patients (group 3) were tested for the IgG anti-HEV. RESULTS: The prevalence of anti-HEV among the HD patients and the healthy controls were 31 and 8.9%, respectively. The difference (22%) was statistically significant (p < 0.01). In comparison, the anti-HEV in hospital patients was 16%. CONCLUSION: The study indicated a significantly higher risk of HEV infection among patients on chronic HD in endemic regions of viral hepatitis such as Taiwan. Mostly because of anaemia, HD patients usually received packed transfusion (red blood cells) if their haemoglobin was low. It is possible that HEV infection may be transmitted through blood transfusions in an endemic area. In such areas, appropriate strategies should be adopted to prevent the risk of HEV among HD patients.

Clearance of fibrinogen and von Willebrand factor in serial double-filtration plasmapheresis.

Double filtration plasmapheresis (DFP) is a widely used and effective way to clear autoantibodies from plasma. It can, however, transiently alter the hemostatic system and cause a bleeding tendency in some patients. There is limited data on the consecutive effect of serial DFP on the hemostatic system, especially on fibrinogen and von Willebrand factor (vWF) levels. This study measured fibrinogen and vWF serially before and after each session of DFP in 8 patients who received one course of DFP treatment for 3 to 5 consecutive sessions on an alternate-day basis. In each session of DFP, the clearance rate of fibrinogen and vWF exceeded 63 and 45%, respectively. The final levels of fibrinogen and vWF after a full course of DFP were reduced to 14.3 and 51.2% of baseline level, respectively. No bleeding tendency was observed in any of the 34 DFP sessions. In conclusion, although an obvious decrease in fibrinogen level and the modest decrease in vWF were observed after an intensive course of DFP treatment, the low incidence of clinically important bleeding confirms the hemostasis-related safety of DFP.