Can Optical Surface Imaging Replace Non-coplanar Cone-beam Computed Tomography for Non-coplanar Set-up Verification in Single-isocentre Non-coplanar Stereotactic Radiosurgery and Hypofractionated Stereotactic Radiotherapy for Single and Multiple Brain Metastases?

AIMS

To conduct a direct comparison regarding the non-coplanar positioning accuracy between the optical surface imaging system Catalyst HDTM and non-coplanar cone-beam computed tomography (NC-CBCT) in intracranial single-isocentre non-coplanar stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (HSRT).

MATERIALS AND METHODS

Twenty patients with between one and five brain metastases who underwent single-isocentre non-coplanar volumetric modulated arc therapy (NC-VMAT) SRS or HSRT were enrolled in this study. For each non-zero couch angle, both Catalyst HDTM and NC-CBCT were used for set-up verification prior to beam delivery. The set-up error reported by Catalyst HDTM was compared with the set-up error derived from NC-CBCT, which was defined as the gold standard. Additionally, the dose delivery accuracy of each non-coplanar field after using Catalyst HDTM and NC-CBCT for set-up correction was measured with SRS MapCHECKTM.

RESULTS

The median set-up error differences (absolute values) between the two positioning methods were 0.30 mm, 0.40 mm, 0.50 mm, 0.15°, 0.10° and 0.10° in the vertical, longitudinal, lateral, yaw, pitch and roll directions, respectively. The largest absolute set-up error differences regarding translation and rotation were 1.5 mm and 1.1°, which occurred in the longitudinal and yaw directions, respectively. Only 35.71% of the pairs of measurements were within the tolerance of 0.5 mm and 0.5° simultaneously. In addition, the non-coplanar field with NC-CBCT correction yielded a higher gamma passing rate than that with Catalyst HDTM correction (P < 0.05), especially for evaluation criteria of 1%/1 mm with a median increase of 12.8%.

CONCLUSIONS

Catalyst HDTM may not replace NC-CBCT for non-coplanar set-up corrections in single-isocentre NC-VMAT SRS and HSRT for single and multiple brain metastases. The potential role of Catalyst HDTM in intracranial SRS/HSRT needs to be further studied in the future.

[Update points for the 2022 edition of the European Association for the Study of Liver Diseases Clinical Practice Guidelines for the Management of Hepatic Encephalopathy and comparison with China's 2018 edition guidelines]

The European Association for the Study of Liver Diseases issued the "Clinical Practice Guidelines for the Management of Hepatic Encephalopathy" in 2022, which included recommendations for clinical diagnosis, assessment, treatment, management, and prevention. The Society's "Hepatic Encephalopathy Clinical Practice Guidelines in Chronic Liver Disease," which was last published in 2014, and the "Guidelines for the Diagnosis and Treatment of Hepatic Encephalopathy in Cirrhosis," which the Chinese Society of Hepatology, Chinese Medical Association, released in 2018, have certain differences and updates in terms of comparison to terminology, grading and classification, diagnosis, clinical evaluation and treatment, management, and prevention. Herein, the updated points of this guideline and the differences between it and our nation's guidelines are summarized in order to refine and understand the guiding role of the new version of the guideline for the clinical treatment of hepatic encephalopathy and provide aid for standardizing clinical diagnosis and treatment.

[Establishment of "Chinese way" for trauma and burn management based on the engineered growth factors research and application]

Innovation and translation application are important topics that have been discussed repeatedly in national community of science and technology in recent years. We do a systemic review about the research and development history of growth factors, their application in trauma and burn management in China, and the conception and experience about the establishment of "Chinese way" for trauma and burn management in the process of constructing a disciplinary system for wound treatment with Chinese characteristics. It is our hope that these precious experiences will provide references and inspiration to our peers, especially the young generation in their research.

[Seizing the day and living it to the full: thirty years' independent innovation of growth factors and wound repair]

Since the discovery of fibroblast growth factor (FGF) in the early 20th century, the multiple regulatory function of FGF has been found in development, metabolic regulation and tissue regeneration. Although FGF has the potential in wound healing of clinical practice, several technical bottlenecks occurred in the development of FGF drugs. Since 1992, our team has had many technical breakthroughs and developed some class Ⅰ new drugs of FGF and medical device. At the same time, we further investigated the network of metabolic regulation and signal transduction of FGF. All the efforts were for the purpose of the development of FGF new drugs and bringing benefit to patients.

Serum hepatitis B surface antigen correlates with fibrosis and necroinflammation: A multicentre perspective in China

The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large-sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)-positive chronic HBV infection (n = 588), HBeAg-positive chronic hepatitis B (n = 596), and HBeAg-negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%-90% confidence interval: 3.52 log10 IU/mL-4.99 log10 IU/mL]) in patients with HBeAg-positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg-positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg-negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg-positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg-negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.

Higher Efficiency of Retrovirus Transduction in the Late Stage of Primary Culture of Hepatocytes from Nontreated than from Partially Hepatectomized Rat

The aim of this investigation was to optimize the conditions for gene transduction by a retroviral vector into primary cultured hepatocytes. Because a retrovirus infection is dependent upon the proliferative activity of the target cells, we examined the thymidine incorporation of the primary culture, using cells from nontreated and partially hepatectomized donor rats. Partial hepatectomy 1 day before cell isolation greatly enhanced the thymidine incorporation, and similarly, the transduction of LacZ, the gene for E. coli β-galactosidase, although the percentage of transduced cells remained low. With cells from the normal rat, the thymidine incorporation increased gradually after the beginning of the culture and reached 16 times the initial activity on day 2, while hepatocytes from the partially hepatectomized donor showed no increase at that stage of the culture. Correspondingly, the number of gene-transduced hepatocytes was increased when the vector was added to the cells 1 or 2 days after isolation. Therefore, hepatocytes cultured for 1 or 2 days after isolation are suitable for retroviral transduction.

Garlic for hypertension: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

In the past decade, garlic has become one of the most popular complementary therapies for blood pressure (BP) control used by hypertensive patients. Numerous clinical studies have focused on the BP-lowering effect of garlic, but results have been inconsistent. Overall, there is a dearth of information available to guide the clinical community on the efficacy of garlic in hypertensive patients.

AIM

To systematically review the medical literature to investigate the current evidence of garlic for the treatment of hypertension.

METHODS

PubMed, the Cochrane Library and EMBASE were searched for appropriate articles from their respective inceptions until August 2014. Randomized, placebo-controlled trials comparing garlic vs. a placebo in patients with hypertension were considered. Papers were independently reviewed by two reviewers and were analyzed using Cochrane software Revman 5.2.

RESULTS

A total of seven randomized, placebo-controlled trials were identified. Compared with the placebo, this meta-analysis revealed a significant lowering effect of garlic on both systolic BP (WMD: -6.71 mmHg; 95% CI: -12.44 to -0.99; P = 0.02) and diastolic BP (WMD: -4.79 mmHg; 95% CI: -6.60 to -2.99; P < 0.00001). No serious adverse events were reported in any of the trials.

CONCLUSION

The present review suggests that garlic is an effective and safe approach for hypertension. However, more rigorously designed randomized controlled trials focusing on primary endpoints with long-term follow-up are still warranted before garlic can be recommended to treat hypertensive patients.

5-aminolevulinic acid combined with sodium ferrous citrate ameliorates H2O2-induced cardiomyocyte hypertrophy via activation of the MAPK/Nrf2/HO-1 pathway

Hydrogen peroxide (H2O2) causes cell damage via oxidative stress. Heme oxygenase-1 (HO-1) is an antioxidant enzyme that can protect cardiomyocytes against oxidative stress. In this study, we investigated whether the heme precursor 5-aminolevulinic acid (5-ALA) with sodium ferrous citrate (SFC) could protect cardiomyocytes from H2O2-induced hypertrophy via modulation of HO-1 expression. HL-1 cells pretreated with/without 5-ALA and SFC were exposed to H2O2 to induce a cardiomyocyte hypertrophy model. Hypertrophy was evaluated by planar morphometry, (3)H-leucine incorporation, and RT-PCR analysis of hypertrophy-related gene expressions. Reactive oxygen species (ROS) production was assessed by 5/6-chloromethyl-2',7'-ichlorodihydrofluorescein diacetate acetylester. HO-1 and nuclear factor erythroid 2-related factor 2 (Nrf2) protein expressions were analyzed by Western blot. In our experiments, HL-1 cells were transfected with Nrf2 siRNA or treated with a signal pathway inhibitor. We found several results. 1) ROS production, cell surface area, protein synthesis, and expressions of hypertrophic marker genes, including atrial natriuretic peptide, brain natriuretic peptide, atrial natriuretic factor, and β-myosin heavy chain, were decreased in HL-1 cells pretreated with 5-ALA and SFC. 2) 5-ALA and SFC increased HO-1 expression in a dose- and time-dependent manner, associated with upregulation of Nrf2. Notably, Nrf2 siRNA dramatically reduced HO-1 expression in HL-1 cells. 3) ERK1/2, p38, and SAPK/JNK signaling pathways were activated and modulate 5-ALA- and SFC-enhanced HO-1 expression. SB203580 (p38 kinase), PD98059 (ERK), or SP600125 (JNK) inhibitors significantly reduced this effect. In conclusion, our data suggest that 5-ALA and SFC protect HL-1 cells from H2O2-induced cardiac hypertrophy via activation of the MAPK/Nrf2/HO-1 signaling pathway.

Ginkgo biloba extract for essential hypertension: a systemic review

BACKGROUND

Ginkgo biloba extract (GBE), a traditional natural herbal product, is often used in the treatment of essential hypertension (EH) as complementary therapy in China and European countries.

AIM

To critically assess the current clinical evidence of efficacy and safety of GBE for EH.

METHODS

7 electronic databases (Cochrane Library, PubMed, EMBASE, VIP, CBM, Wanfang data, and CNKI) were searched to identify randomized controlled trials (RCTs) of GBE for EH. Methodological quality was assessed independently using the Cochrane Handbook for Systematic Reviews of Interventions.

RESULTS

A total of 9 RCTs with 1012 hypertensive patients were identified and reviewed. Most RCTs were of high risk of bias with flawed study design and poor methodological quality. 6 trials demonstrated potential positive effect of GBE as complementary therapy on BP reduction when compared with antihypertensive drug therapy; however, it was not associated with a statistically significant effect on both SBP and DBP reduction in 3 other trials. Despite the positive findings, there were so many methodological limitations and significant clinical heterogeneity. Most of the trials did not report adverse effects, and the safety of GBE is still uncertain.

CONCLUSION

No confirmative conclusions on the efficacy and safety of GBE for EH could be drawn. More rigorous trials are warranted to support their clinical use.

The PI3K/Akt signal hyperactivates Eya1 via the SUMOylation pathway

Eya1 is a conserved critical regulator of organ-specific stem cells. Ectopic Eya1 activities, however, promote transformation of mammary epithelial cells. Signals that instigate Eya1 oncogenic activities remain to be determined. Here, we show that Akt1 kinase physically interacts with Eya1 and phosphorylates a conserved consensus site of the Akt kinase. PI3K/Akt signaling enhances Eya1 transcription activity, which largely attributes to the phosphorylation-induced reduction of Eya1 SUMOylation. Indeed, SUMOylation inhibits Eya1 transcription activity; and pharmacologic and genetic activation of PI3K/Akt robustly reduces Eya1 SUMOylation. Wild type but not Akt phosphorylation site mutant Eya1 variant rescues the cell migratory phenotype of EYA1-silenced breast cancer cells, highlighting the importance of Eya1 phosphorylation. Furthermore, knockdown EYA1 sensitizes breast cancer cells to the PI3K/Akt1 inhibitor and irradiation treatments. Thus, the PI3K/Akt signal pathway activates Eya1. These findings further suggest that regulation of SUMOylation by PI3K/Akt signaling is likely an important aspect of tumorigenesis.

Regenerated host axons form synapses with neurons derived from neural stem cells transplanted into peripheral nerves

It is reported that neural stem cells (NSC) can arrest denervated muscle atrophy and promote nerve regeneration when transplanted into injured peripheral nerves, and that regenerated host axons can form synapses with transplanted and differentiated NSC. In this study, F344 rat nerve segments and F344 rat NSC were transplanted into host green fluorescence protein (GFP) transgenic F344 rats. This allowed transplanted F344 rat tissue to be used as a nonluminous background for the clear visualization of regenerated host GFP axons. Regenerated host axons grew into the transplanted F344 nerve segment 2 weeks after nerve anastomosis. Immunohistochemical staining and confocal microscope analysis revealed that regenerated host axons formed synapses with NSC-derived neurons. The findings confirmed that regenerated peripheral axons form synapses with neurons in peripheral nerves, possibly forming the basis for clinical application in peripheral nerve injury.

Efficiencies of residual organic pollutants removal from secondary effluent by switching of coagulation- air flotation -filtration processes

It is an essential task to remove the residual organic pollutants (ROP) from secondary effluent of a Wastewater Treatment Plant (WWTP) in wastewater reclamation and reuse processes. Four different compared flow schemes would be achieved for further purification of the secondary effluent by switching of different valves. In order to mainly remove non-biodegradable residual organic pollutants under various operating conditions, the optimum technology and economic process was obtained in the advanced purification flow scheme at a flow of 3200 m(3)/d in Harbin Wenchang WWTP. Conclusions under a lot of experiments show that: choosing the coagulation-settler plus biofilm filter for advanced purification process is reasonable; during the stable operation phase, this process showed good performance in removing the COD, BOD5, TP, NH3-N and SS; the removal rates are 50%, 39%, 67%, 50%, 80% respectively. The effluent is able to excel the requirements for wastewater reuse standards. The unit cost of the water is 0.542 yuan/m(3), which is far below the fee paid for supply water, long-distance transfer water or seawater desalination through economic analysis.

Selective repopulation of mice liver after Fas-resistant hepatocyte transplantation

Hepatocyte transplantation has been proposed as a potential therapeutic method to treat irreversible liver failure and inherited hepatic disorders, although transplanted cells do not easily reconstruct the liver tissue under intact conditions. This study was aimed at modulating the recipient liver conditions to promote repopulation of the liver after hepatocyte transplantation. Hepatocytes isolated from male MRL-lpr/lpr (lpr) mice with a mutation of Fas antigen were transplanted in a number of 1 x 10(6) cells in female MRL-+/+ (wild-type mice) by intrasplenic injection. An agonistic anti-Fas antibody (0.15 mg/kg) was administered intravenously 24 h after cell transplantation. We also administrated the antibody at 0.3 mg/kg 1 week after grafting and at 0.6 mg/kg 2 weeks after transplantation. The liver specimens were taken at different time intervals for histological examination. The reconstructed male lpr hepatocytes in the female wild-type mice were determined by a real-time quantitative PCR assay using the primers and probe for the sry gene. The pathologic findings of the recipient livers after treatment with anti-Fas antibody revealed a large number of apoptotic hepatocytes. The grafted lpr hepatocytes were observed to reconstruct as much as 6.9% of the recipient liver in the anti-Fas antibody-treated group 3 months after transplantation. In contrast, we observed the transplanted cells at lower than 0.1% in the nontreated livers. These findings demonstrated that repeated induction of apoptosis in recipient hepatocytes shifts the environment of the liver to a regenerative condition. This method may be useful to promote the reconstruction of transplanted hepatocytes in a recipient liver.

Cytological examination of rat amniotic epithelial cells and cell transplantation to the liver

It is hoped that amniotic epithelial cells can be useful in cell-mediated gene therapy. We report here an experimental cell transplantation model of amniotic cells in rats. There is an anatomical difference between human and rodent embryos. We established a method to isolate amniotic cells that are equivalent to human amniotic epithelial cells. An amniotic membrane distinct from the yolk sac was carefully collected and teased in saline containing deoxyribonuclease and hyaluronidase, followed by collagenase digestion. The cell yield was approximately 10(6) cells per pregnant female (10(5) cells per fetus), roughly in proportion to the age of fetus used, and 60% of the isolated cells were attached to the dish under culture conditions. Telomerase activity was higher in the cells isolated from fetuses in the middle stage (day 13.5 to 15.5) than in the late stage (day 17.5 to 21.5). Adherent cells exhibited two to three times more cell division, resulting in a ninefold increase in the number of cells. Immunohistochemical analysis revealed that approximately half of the adherent cells were albumin positive and formed clusters. The senescent cells survived for 2 months without apparent morphological changes. The adherent cells were able to be stored in liquid nitrogen and had a viability of 70% when thawed. Gene transduction with adenovirus vector was highly effective for rat amniotic cells. Transplantation of lacZ transfected amniotic cells into syngeneic rat liver resulted in the integration of the transplanted cells in the liver structure and the cells survived for at least 30 days.

Widespread distribution of adenovirus-transduced monkey amniotic epithelial cells after local intracerebral injection: implication for cell-mediated therapy for lysosome storage disorders

Cell-mediated therapy for mucopolysaccharidosis type VII (MPSVII) was studied using monkey amniotic epithelial cells (mAEC). The cells were transduced with a recombinant adenovirus expressing human beta-glucuronidase (GUSB), and cells overexpressing GUSB were generated. The cells expressed 2000-fold higher activities than the endogenous GUSB activities of nontransduced mAEC, demonstrating that mAEC were successfully transduced with adenoviral vectors. These cells also secreted high levels of GUSB. To clarify the cross-correction of GUSB secreted from mAEC, the conditioned medium containing high levels of GUSB was added into the medium for culturing human or murine fibroblasts established from an MPSVII patient or a mouse model of the disease. Dramatic increases in GUSB activities were observed in both fibroblasts. We then transplanted the cells transduced with an adenovirus expressing LacZ into the caudate-putamen of monkey brain. Survival and distribution of the transplanted cells 1 month after the treatment were evaluated. Histochemical analysis showed that LacZ-positive cells were widely distributed in the brain, suggesting that the transplanted cells had migrated and were distributed even at regions far from the implantation site. These findings suggest that local intracerebral engraftment of genetically engineered amniotic epithelial cells is favorable for the treatment of lysosome storage disorders, whose pathological abnormalities are not restricted to specific regions of the brain.

Activation of caspases and mitochondria in FTY720-mediated apoptosis in human T cell line Jurkat

FTY720, a novel immunosuppressive drug originally derived from a metabolite from Isaria sinclairii, is known to induce apoptosis in lymphocytes. In this study, we investigated the involvement of caspases and mitochondria in FTY720-mediated apoptosis using Jurkat cells, a human T cell line. Our results indicated that FTY720-induced activation of caspases 2, 3, 6, 8, 9 and 10, whereas caspases 1 and 5 were not activated. We also observed in the FTY720-treated cells a loss of mitochondrial membrane potential, a release of cytochrome c into cytosol and an exposed phosphatidylserine (PS) at the outer surface of the cell membrane. Pretreatment with a peptide inhibitor, benzyloxycarbonyl-Asp-CH2COC-2, 6-dichlorobenzene (Z-Asp-CH2-DCB), prevented apoptosis and externalization of phosphatidylserine, whereas the inhibitor did not prevent the mitochondrial events. This suggests that caspases may play a role downstream of the mitochondrial pathway. Therefore, caspase cascade in FTY720-treated cells may be initiated by activation of mitochondria.

Expression of Bcl-2 family reduces apoptotic hepatocytes after excessive hepatectomy

Excessive hepatectomy often causes fatal hepatic failure, but the mechanism is unknown. We used a novel protocol of partial 90 and 95% hepatectomy (PHx) to investigate this mechanism in 2 groups of rats. The 90% PHx rats survived, but the 95% PHx animals died of hepatic failure. In the latter, cytokine (interleukin-6, tumor necrosis factor-alpha) levels and the apoptotic hepatocyte count increased, and there were few mitotic cells. By contrast, in the 90% PHx rats, the mitotic cell count increased, and more anti-apoptotic Bcl-xL protein was expressed. These results demonstrate that expression of Bcl-xL protein as an anti-apoptotic factor or regeneration factor contributes to survival after 90% PHx. Using an adenovirus vector, the human bcl-2 gene (hbcl-2) was therefore transfected to DA rat livers where it was efficiently expressed, and then 95% PHx was performed. Liver damage was decreased and the apoptotic cell count decreased too, but the rats died. We concluded that transfection of the hbcl-2 gene partly prevents cytotoxicity (apoptosis), but cannot ensure survival. Thus, some other factor is required (e.g., a regeneration stimulator) to maintain life in these models.

Microchimeric cells from the peripheral blood associated with cardiac grafts are bone marrow derived, long-lived and maintain acquired tolerance to minor histocompatibility antigen H-Y

BACKGROUND

Although it has been well established that the microchimerism occurs in the peripheral blood of the recipients after various settings in both clinical and experimental organ transplantation, nevertheless, their roles in inducing and maintaining acquired transplantation tolerance are controversial. Furthermore, regarding the cell lineages, kinetics, and functions of the cells that constitute the microchimerism after organ transplantation, solid information is not available.

METHODS

Using rat heterotopic heart isografts from bone marrow chimeras between cross-sex and applying polymerase chain reaction with specific primers to rat sex determining region of Y chromosome, a relationship between a state of microchimerism and induction as well as maintenance of acquired tolerance to H-Y antigen were examined.

RESULTS

Microchimeric cells of the peripheral blood (MCPB) after cardiac grafting contain bone marrow-derived and radiation-sensitive cells. Furthermore, removal of the primary cardiac grafts revealed that microchimeric cells in the peripheral blood are long-lived cells, i.e., more than 6 months. When the female rats that had contained long-lasting MCPB, were innoculated with syngeneic male dendritic cells, failure to sensitize female toward male specific antigen H-Y was found to occur.

CONCLUSIONS

Thus it was suggested that radiation-sensitive, bone marrow derived, long-lived MCPB play a significant role in maintaining acquired transplantation tolerance to minor histocompatibility antigen H-Y.

In vitro prevention of cell-mediated xeno-graft rejection via the Fas/FasL-pathway in CrmA-transducted porcine kidney cells

Cell-mediated cytotoxicity may be involved in delayed and/or chronic xenograft rejection in which apoptosis is induced in the grafted cells via the Fas/Fas-ligand (FasL) and perforin/granzyme pathways. One barrier to the potential use of xeonogenic grafts for humans may be Fas/FasL-mediated apoptosis, which would be blocked by the gene expression of cytokine response modifier A (CrmA), a cowpox virus gene product. The purpose of this study is to explore whether crmA is an effective candidate gene for inhibiting apoptosis in an in vitro model of xenograft rejection, using Fas-expressing non-primate cells cultured with a soluble recombinant human FasL (sFasL). A recombinant adenovirus vector expressing CrmA (AxCALNLCrmA) was successfully generated with a Cre-mediated switching system. PK15 cells, derived from a porcine kidney and infected with AxCALNLCrmA and/or AxCANCre at a multiplicity of infection (MOI) ranging from 0.1 to 100, were cultured with human sFasL derived from KFL74.18, a human FasL-overexpressed cell line. The gene-expression level of the PK15 cells was confirmed by CrmA-immune staining. Approximately 70% of the control PK15 cells showed induced apoptosis when cultured with sFasL. In contrast, the apoptosis was dramatically reduced in crmA-gene-transduced PK15 cells. The inhibitory effect of apoptosis increased with an increase in the infection dose of AxCANCre. In addition, the activity of caspases 3 and 8 was significantly inhibited in the crmA-transduced cells. These results indicate that CrmA is an effective gene product for inhibiting Fas/FasL-mediated apoptosis, which suggests the potential therapeutic use of its gene transduction to protect against graft damage due to delayed and/or chronic xenograft rejection.

Long-term graft acceptance in rat heart transplantation by CTLA4Ig gene transfection combined with FTY720 treatment

CTLA4Ig strongly adheres to B7 molecules on antigen-presenting cells to block intracellular signal transduction via CD28 on helper T cells, which eventually inhibits immune responses. We have demonstrated that the administration to recipient animals of adenoviral vectors containing CTLA4Ig gene (adCTLA4Ig) prolonged graft survival, although the gene expression diminished in a time-dependent manner and the grafts were finally rejected. In addition, recipient animals treated with FTY720, a new immunosuppressant, exhibited a decrease in the number of peripheral lymphocytes due to apoptosis. In this study, we performed adCTLA4Ig transfection combined with FTY720 treatment in heart-grafted rats to determine if the combination could induce a mutual effect on graft survival. The recipient animals were given injections of 1 x 10(9) plaque-forming units of adCTLA4Ig via the tail vein immediately after grafting. On the day before transplantation we administered FTY720 orally to some of these animals at a dosage of 5 mg/kg and again on the day of transplantation. The median graft survival period in the adCTLA4Ig-only group was 27 days, whereas that in the combination group was markedly prolonged to 56 days. Of 15 grafts, 5 survived indefinitely. In these groups we observed detectable levels of CTLA4Ig in the sera 49 days after grafting; the levels were always higher in the combination group than in the adCTLA4Ig-only group. As a result, this study revealed that FTY720 and adCTLA4Ig have a potent mutual effect on graft survival during rat heart transplantation. Furthermore, it is highly possible that FTY720 enhances gene expression of adCTLA4Ig, which may be related to the long-term acceptance of grafts.

Fulminant hepatitis by Fas-ligand expression in MRL-lpr/lpr mice grafted with Fas-positive livers and wild-type mice with Fas-mutant livers

BACKGROUND

Fulminant hepatitis in mice could be induced by gene-transfection of Fas ligand (FasL). However, the mechanisms of this event still remain controversial as to whether it is mediated by direct Fas/FasL interaction and/or neutrophil migration. To investigate the role of exogenous FasL-expression, we established a simple but clear mouse model on which we performed liver transplantation between Fas-mutant mice (MRL-lpr/lpr) and wild-type mice (MRL+/+).

METHODS

The controls were nontransplanted wild-type (group 1) and MRL-lpr/lpr (group 2) mice. We obtained recipients with a Fas defect only in the liver (group 3; MRL-lpr/lpr liver graft in wild-type mice) and Fas-defected recipients with Fas-positive livers (group 4; wild-type graft in MRL-lpr/lpr). We successfully expressed FasL in the liver by cotransfection of two types of adenoviral vectors, AxCALNFasL and AxCANCre, with a Cre-loxP switching system.

RESULTS

FasL-expression in the livers in groups 3 and 4 resulted in animal death due to fulminant hepatitis within 48 hr after administration of the vectors. We obtained similar findings in group 1, whereas the mice in group 2 survived without any evidence of hepatitis. Immune staining revealed a marked infiltration of CD11b-positive cells in group 1 and group 3. Despite the number of apoptotic cells, a few infiltration of CD11b-positive cells were seen in group 4. We observed no remarkable findings in the FasL-expressed livers in group 2.

CONCLUSION

The results indicated that exogenous FasL-expression induces hepatocyte apoptosis both by direct interaction with Fas and by recruiting Fas-positive inflammatory cells. These findings are important for generating a new strategy to prevent hepatitis as well as for understanding the role of the Fas/FasL interaction in the pathophysiology of hepatitis.

Induction of lymphocyte apoptosis in rat liver allograft with ongoing rejection by FTY720

The action mechanism of FTY720, a novel immunosuppressant, is completely different from conventional immunosuppressants. The drug, which triggers apoptosis in murine and human lymphocytes, has a potent immunosuppressive activity to prevent allograft rejection without any severe side-effect. The present study was designed to determine whether FTY720 induces apoptotic cell death in activated lymphocytes infiltrated into liver grafts with ongoing rejection. FTY720 was orally administered at 5 mg/kg to the recipients on day 3 and day 4 after grafting, when the graft rejection was histologically confirmed. The intragraft patterns of IL-2, interferon-gamma (IFN-gamma), perforin, and granzyme B gene expression were detected by reverse transcriptase-polymerase chain reaction. The treatment reversed ongoing rejection and significantly prolonged recipient survival time compared with the control group. Light microscopic observation of the graft sections stained with the DNA nick-end labelling method showed that the apoptosis in the control allografts was mainly induced in hepatocytes, while that in the FTY720-treated allografts was in infiltrated lymphocytes. The rejection therapy with FTY720 did not alter the expression of IL-2, IFN-gamma, and perforin mRNAs, but slightly decreased granzyme B expression. Our results suggest that FTY720 does not alter the intrinsic lymphocyte function to produce the rejection-related cytokines, but strongly induces apoptotic cell death in the activated lymphocytes. Thus, FTY720 affords new insight into the mechanisms underlying improvements in immunosuppressive treatments.

Engraftment of genetically engineered amniotic epithelial cells corrects lysosomal storage in multiple areas of the brain in mucopolysaccharidosis type VII mice

Cell-mediated gene therapy for visceral lesions of lysosomal storage diseases is promising; however, the treatment of central nervous system (CNS) lesions remains a challenge. In this study, we generated rat amniotic epithelial cells (AEC) that overexpress and secrete human beta-glucuronidase (GUSB) following transduction with an adenoviral vector encoding human GUSB. The AEC were used as donor cells for cell-mediated gene therapy of CNS lesions in mice with mucopolysaccharidosis type VII (MPSVII), a lysosomal storage disorder caused by an inherited deficiency of GUSB activity. After confirmation that the secreted GUSB was taken up mainly via mannose 6-phosphate receptors in primary cultured neurons, the AEC were transplanted into the brains of adult MPSVII mice. Histochemical analysis showed extensive GUSB activity throughout the ipsilateral hemisphere of the recipient brains, and pathological improvement of the lysosomal storage was observed even in regions far from the site of injection. These results suggest that intracerebral transplantation of genetically engineered AEC has therapeutic potential for the treatment of CNS lesions in lysosomal storage disorders.

Huanglian, A chinese herbal extract, inhibits cell growth by suppressing the expression of cyclin B1 and inhibiting CDC2 kinase activity in human cancer cells

Huanglian is an herb that is widely used in China for the treatment of gastroenteritis. We elected to determine whether huanglian could inhibit tumor cell growth by modulating molecular events directly associated with the cell cycle. Huanglian inhibited tumor growth and colony formation of gastric, colon, and breast cancer cell lines in a time- and dose-dependent manner. Cell growth was completely inhibited after 3 days of continuous drug exposure to 10 microg/ml of herb. This degree of growth inhibition was significantly greater than that observed with berberine, the major constituent of the herb. The inhibition of cell growth by huanglian was associated with up to 8-fold suppression of cyclin B1 protein. This resulted in complete inhibition of cdc2 kinase activity and accumulation of cells in G(2). The mRNA expression of cyclin B1 was not changed after huanglian treatment. There was no change in the protein expression of cyclins A or E. Therefore, the effect of huanglian on inhibiting tumor growth seems to be mediated by the selective suppression of cyclin B1, which results in the inhibition of cdc2 kinase activity. Inhibition of cyclin dependent kinase (cdk) activity is emerging as an attractive target for cancer chemotherapy. Huanglian represents a class of agents that can inhibit tumor cell growth by directly suppressing the expression of a cyclin subunit that is critical for cell cycle progression. These results indicate that traditional Chinese herbs may represent a new source of agents designed for selective inhibition of cyclin dependent kinases in cancer therapy.

Direct computation of multiple 3D flow convergence isovelocity surfaces from digital 3D reconstruction of colour Doppler data of the flow convergence region: an in vitro study with differently shaped orifices

AIMS

Evaluation of the accuracy of direct computation of multiple three-dimensional (3D) flow convergence (FC) isovelocities by using digital reconstruction of colour Doppler data of the flow convergence region.

METHODS AND RESULTS

We used a conventional ultrasound system (ATL HDI 3000) connected to a computer workstation via Ethernet link. The digital 3D datasets were directly transferred to a Silicon Graphic Imaging Octane workstation for later measurement. We generated nine pulsatile flows (20-60 ml/beat), with peak flow rates (67-180 ml/s), through three orifices (circular, rectangular and triangular, S=0.24 cm(2)). The 3D reconstructions of FC surface areas from multi-threshold velocities, including aliasing velocities were analysed to quantify the peak flow rate. For all orifices, linear regression demonstrated excellent correlation between the 3D calculated and electromagnetic flow meter recorded data. While there was a high correlation for 3D computation of flow rate from the single best Nyquist of 24 cm/s (r=0.97-0.98, SEE=7 .75-12.58 ml/s), the ability to average three threshold velocities (15, 18 and 24 cm/s) yielded an improved correlation (r=0.98-0.99, SEE=5.70-7.73 ml/s).

CONCLUSIONS

Direct computation of multiple 3D FC isovelocities from digital reconstruction of colour Doppler data of the FC region provides the potential to accurately quantify the complex asymmetric spatial flow events at any selected velocity.

Long-term culture of glutamine synthetase-transfected HepG2 cells in circulatory flow bioreactor for development of a bioartificial liver

Glutamine synthetase (GS) is involved in an accessory pathway of ammonia removal in mammals. To develop a bioartificial liver with a human cell line, GS gene was transfected into HepG2 cells, which had no ammonia removal activity. After culturing in the presence of methionine sulfoximine (MSX), a GS inhibitor, we obtained a MSX-resistant HepG2 subline (GS-HepG2), which had amplified GS gene; ammonia removal activity was estimated to be 1/7 of that of rat primary culture hepatocytes. The cells were cultured in a circulatory flow bioreactor for 109 days, while they multiplied from 5 x 10(7) to 4 x 10(9) cells. Three days after inoculation, the ammonia level of the culture medium was lowered to a level maintained thereafter, suggesting that using recombinant cell lines for bioartificial livers enables long-term repeated treatment for hepatic failure patient. Judging from the rate of decrease in the amount of the added ammonia, the ammonia removal capability of 4 x 10(9) GS-HepG2 cells was almost equivalent to 5 x 10(8) porcine hepatocytes inoculated into the circulatory flow bioreactor. Apart from their ammonia removal activity, GS-HepG2 cells eliminated human tumor necrosis factor-alpha (TNF-alpha). Cytokine removal therefore promises to be another useful property of bioreactor cells.

Phenotype correction in murine mucopolysaccharidosis type VII by transplantation of human amniotic epithelial cells after adenovirus-mediated gene transfer

Cell therapy with human amniotic epithelial (HAE) cells was developed as an alternative method for enzyme replacement therapy in congenital lysosomal storage disorders, but only limited therapeutic efficacy has been reported. A major drawback is insufficient production and secretion of lysosomal enzymes from HAE cells. In this study, we infected HAE cells with an E1-deleted adenoviral vector expressing human beta-glucuronidase (GUSB), and generated cells overexpressing GUSB by a hundred times as much as endogenous GUSB in untreated HAE cells. GUSB secreted from the gene-transferred HAE cells were efficiently transported to murine fibroblasts with endocytosis mediated by mannose-6-phosphate receptors. The cells were administered into the spleen of the mice with the lysosomal storage disease mucopolysaccharidosis type VII (B6/MPSVII). Approximately 10-15% of the normal GUSB activity was detected in both liver and spleen 7 days after the cell administration. Histopathological examination showed that lysosomal enlargement in tissue macrophages in the liver and the spleen had disappeared by day 14. These results suggest that transplantation of the HAE cells transduced with adenoviral vectors can be employed for the treatment of congenital lysosomal storage disorders.

Strong, long-term transgene expression in rat liver using chicken beta-actin promoter associated with cytomegalovirus immediate-early enhancer (CAG promoter)

For successful gene therapy in hepatic enzyme deficiencies, it is essential to use promoters that can maintain strong transcriptional activity for the long term in the liver. Using Gunn rats, a model animal for Crigler-Najjar syndrome type I, the long-term transcriptional function of the CAG promoter (a combination of chicken beta-actin promoter and cytomegalovirus immediate-early enhancer) was evaluated in the rat liver. We constructed a plasmid pCAGGHUGT, containing expression cassettes of human bilirubin UDP-glucuronosyltransferase (BUGT) and hygromycin phosphotransferase, under the control of the CAG promoter and murine phosphoglycerate kinase promoter, respectively. Conditionally immortalized Gunn rat hepatocytes (IGRH), which had been established using mutant SV40 large T antigen ((TS)T), were transfected with pCAG-GHUGT. A stably transfected clone IGRHUGT, expressing a high level of BUGT, was obtained after selection with hygromycin. At 33 degrees C, the cells doubled in number in approximately 72 h; however, at 37 degrees C, cell proliferation stopped, indicating that the characteristic of temperature-dependent proliferation was retained in this clone. Ten million cells were injected into the spleen of syngeneic Gunn rats five times at 10-day intervals. Serum bilirubin levels were reduced by 45-50% at 70 days after the first transplantation and remained so throughout the duration of the study (120 days). These results suggested that the CAG promoter was able to maintain strong transcriptional activity in rat liver for at least 120 days.

Inhibition of Fas-mediated fulminant hepatitis in CrmA gene-transfected mice

Hyperimmune response via Fas/Fas-ligand and perforin/granzyme pathways may be essential in pathogenesis of virus-induced fulminant hepatitis. CrmA inhibits activation of caspases and granzyme B, suggesting it may block these pathways. We investigated whether CrmA expression would inhibit Fas-associated lethal hepatitis in mice. We successfully generated AxCALNLCrmA, a recombinant adenovirus expressing CrmA gene with a Cre-mediated switching cassette. We increased CrmA expression level in the liver transfected with AxCALNLCrmA (10(9) pfu) by increasing administration dose (10(7)-10(9) pfu) of AxCANCre, a recombinant, adenovirus-expressing Cre gene. Injection of anti-Fas antibody into the control mice rapidly led to animal death due to massive liver apoptosis, while the apoptosis was dramatically reduced in the CrmA-expressed mice. The animal survival increased with an increase of CrmA expression. The formation of active caspase-3 was markedly inhibited in the crmA-transfected hepatocytes in vitro. These results suggest that crmA is an effective gene that can inhibit immune-related liver apoptosis.

Adenovirus-mediated gene therapy for mucopolysaccharidosis VII: involvement of cross-correction in wide-spread distribution of the gene products and long-term effects of CTLA-4Ig coexpression

Recombinant adenoviruses expressing human beta-glucuronidase (AxCAhGUS) and CTLA-4Ig (AxCACTLA-4Ig) were generated and therapeutic efficacy was investigated using a murine model of mucopolysaccharidosis type VII (MPSVII). Seven days after the intravenous administration of AxCAhGUS, high levels of beta-glucuronidase (GUSB) activity were observed in the liver, spleen, heart, lung, kidney, and serum, while viral DNA was predominantly detected in the liver. To investigate the contribution of in vivo cross-correction of GUSB between the liver and other organs, we injected the serum obtained from the transduced mice into untreated MPSVII mice. Similar distributions of GUSB activity were observed in the serum-injected mice, suggesting that GUSB activities detected in the extrahepatic organs were due to the cross-correction rather than the direct gene transduction. This result also suggested that maintaining high levels of GUSB in the systemic circulation was essential for the effective treatment of MPSVII. To achieve this, we injected AxCAhGUS and AxCACTLA-4Ig into MPSVII mice. Serum GUSB activity was sustained at high levels for more than 200 days and morphological normalization of the liver and spleen was observed for a year. This suggests that long-term therapeutic efficacy in visceral organs of MPSVII is achievable by coexpression of CTLA-4Ig through an in vivo cross-correction pathway.

An improved method for the purification of stellate cells from rat liver with dichloromethylene diphosphate (CL2MDP)

Hepatic perisinusoidal cell population consists of hepatic stellate cells, Kupffer cells, endothelial cells, and Pit cells. These cells are isolated by enzymic digestion and purified by density gradient centrifugation. With isolation of stellate cells, conventional method is unable to eliminate the contamination of Kupffer cells because the densities of these two cells are similar. We report here an improved method for isolation of highly purified hepatic stellate cells, using dichloromethylene diphosphate (CL2MDP), which has selective cytotoxicity of Kupffer cells. Three days after the single intravenous administration of liposome-encapsulated CL2MDP, the Kupffer cells disappeared almost completely from the liver. Following Percoll density gradient centrifugation, the purity of the hepatic stellate cells exceeded 98% without any contamination of the Kupffer cells. Kupffer cells are reported to affect the physiological functions of stellate cells. The availability of highly purified stellate cells will facilitate the investigation of their functions in primary culture.

The in vivo effect of bryostatin-1 on paclitaxel-induced tumor growth, mitotic entry, and blood flow

Pretreatment of tumor cells with the protein kinase C (PKC) inhibitor bryostatin-1 enhances the cytotoxicity of most chemotherapeutic agents. However, in the case of paclitaxel, this effect has been shown in vitro to be best achieved when bryostatin-1 follows (rather than precedes) paclitaxel treatment. With combination trials of bryostatin-1 and paclitaxel planned for clinical trials and with only in vitro data available regarding drug sequence, we elected to undertake an in vivo study evaluating the effect of sequential bryostatin-1 and paclitaxel in a tumor-bearing mouse model and to correlate this effect to cell cycle events, tumor metabolism, and tumor blood flow. At the maximum tolerated i.p. dose, bryostatin-1 at 80 microg/kg resulted in a small but significant increase in tumor doubling time (4.2 +/- 0.3 days) compared with control tumors (3.0 +/- 0.3 days; P < 0.01). Mice treated with i.v. paclitaxel, administered at a dose of 12 mg/kg every 12 h for three doses, weekly for 3 weeks, had a tumor doubling time of 23.4 +/- 1.7 days. Mice pretreated with i.p. bryostatin-1 (80 microg/kg) followed 12 h later by i.v. paclitaxel (12 mg/kg every 12h for three doses) weekly for 3 weeks had a tumor doubling time of 9.7 +/- 1.1 days. This was significantly less (P < .001) than paclitaxel alone, which indicated an inhibitory effect by bryostatin-1 on paclitaxel therapy. In comparison, tumor-bearing mice that were treated with the same dose but with the sequence of paclitaxel followed by bryostatin-1 had a tumor doubling time of 29.6 +/- 0.6 days. This was significantly greater than the tumor doubling times for any condition tested (P < 0.01), demonstrating the sequence dependence of this combination. The efficacy of paclitaxel is dependent on mitotic entry, a step that requires activation of p34cdc2 kinase activity. Treatment with paclitaxel in vivo increased p34 cdc2 kinase activity in the mouse mammary tumors, whereas administration of bryostatin-1 before paclitaxel prevented the p34cdc2 kinase activation by paclitaxel. This was further evaluated in vitro by flow cytometry in MKN-74 human gastric cancer cells. As determined by MPM-2 labeling, which identifies cells in mitosis, pretreatment with bryostatin-1 prevented paclitaxel-treated cells from entering mitosis. Bryostatin-1 has been reported to induce changes in muscle metabolism and to decrease muscle blood flow. These events could impact on the interaction of bryostatin-1 with paclitaxel. Using proton-decoupled phosphorus nuclear magnetic resonance (31P-NMR) spectroscopy in vivo, bryostatin-1 at 80 micro1g/kg induced a decrease in both intratumoral pH and high-energy phosphates. In vivo perfusion studies, using dynamic enhanced NMR imaging with gadolinium diethylenetriamine pentaacetic acid, also demonstrated decreased tumor blood flow. These studies suggest that the inhibition of tumor response to paclitaxel by bryostatin-1 is multifactorial and includes such diverse factors as inhibition of cell entry into mitosis, a decrease in pH and energy metabolism, and a decrease in tumor blood flow. These results indicate that, as this combination enters Phase I clinical trials, the sequence of paclitaxel followed by bryostatin-1 will be critical in the clinical trial design.

Immunosuppressive therapy using FTY720 combined with tacrolimus in rat liver transplantation

BACKGROUND

FTY720 (FTY) exerts its effects through a reduction of peripheral lymphocytes. This unique mechanism allows for a possible combination effect with other immunosuppressants. We investigated therapy with FTY combined with tacrolimus (FK) in rat liver transplantation.

METHODS

Different doses of FK, FTY, or both were orally administered to the recipients for 15 days. Expression of cytokine mRNAs using RT-PCR and appearance of lymphocyte apoptosis by immunohistologic staining were studied in the allografts.

RESULTS

Recipients treated with a low dose of FK (0.3 mg/kg) or FTY (0.03 mg/kg) showed a slightly prolonged survival time, although combination therapy with these drugs prolonged survival time similar to the duration obtained by an optimal dose of each drug alone. A marked suppression of lymphocyte infiltration and decreased levels of mRNAs for IL-2, IFN-gamma, and granzyme B were seen in the grafts with combination therapy. Grafts with combination therapy showed an increased number of cells double-stained with TUNEL and CD2 in infiltrated lymphocytes.

CONCLUSIONS

Allografts that underwent combination therapy demonstrated markedly reduced lymphocyte infiltration; a number of cells had induced apoptosis and an inhibition of IL-2, IFN-gamma, and granzyme B mRNA transcription, but not IL-4 and IL-10 transcripts, accounting for powerful mutual effect of FTY and FK.

Nitrosyl hemoglobin detected by near-infrared spectroscopy in rat liver allografts

Near-infrared spectroscopy (NIRS) is a noninvasive biomeasurement system with rays in the near-infrared region that possess high permeability to biological tissues. NIRS was applied to liver allografts undergoing rejection in rats treated with deoxyspergualin (DSG) or tacrolimus (FK506). The nitrosyl hemoglobin (Hb) levels detected in the liver grafts increased 3 days and 5 days after grafting in both allogeneic and syngeneic transplantation. The levels on day 8 remained high in the allogeneic graft, but markedly decreased in the syngeneic graft. Although the serum levels of nitrite and nitrate were extremely low 8 days after grafting in allografted recipients treated with DSG or FK506, the nitrosyl-Hb level in DSG-treated graft was much higher than that in FK506-treated graft. There was no significant difference in survival time between DSG-treated and FK506-treated recipients. In conclusion, DSG and FK506 have a different effect on NO production in allografted liver with ongoing rejection, and circulating nitrite and /nitrate levels do not reflect the local levels of NO in the graft.