High-Volume Plasmaexchange: An Effective Tool in Acute Liver Failure Treatment

Pluripotent Stem Cell-derived Strategies to Treat Acute Liver Failure: Current Status and Future Directions

Liver disease has long been a heavy health and economic burden worldwide. Once the disease is out of control and progresses to end-stage or acute organ failure, orthotopic liver transplantation (OLT) is the only therapeutic alternative, and it requires appropriate donors and aggressive administration of immunosuppressive drugs. Therefore, hepatocyte transplantation (HT) and bioartificial livers (BALs) have been proposed as effective treatments for acute liver failure (ALF) in clinics. Although human primary hepatocytes (PHs) are an ideal cell source to support these methods, the large demand and superior viability of PH is needed, which restrains its wide usage. Thus, a finding alternative to meet the quantity and quality of hepatocytes is urgent. In this context, human pluripotent stem cells (PSC), which have unlimited proliferative and differential potential, derived hepatocytes are a promising renewable cell source. Recent studies of the differentiation of PSC into hepatocytes has provided evidence that supports their clinical application. In this review, we discuss the recent status and future directions of the potential use of PSC-derived hepatocytes in treating ALF. We also discuss opportunities and challenges of how to promote such strategies in the common applications in clinical treatments.

Therapeutic plasma exchange versus double plasma molecular absorption system in hepatitis B virus-infected acute-on-chronic liver failure treated by entercavir: A prospective study

BACKGROUND

Therapeutic plasma exchange (TPE) and double plasma molecular absorption system (DPMAS) were two extracorporeal liver support systems. Few studies compared their efficacy profile.

OBJECTIVE

This study was to compare the efficacy of TPE and DPMAS on acute-on-chronic liver failure (ACLF) caused by hepatitis B virus (HBV-ACLF).

METHODS

60 HBV-ACLF patients were enrolled and prospectively studied. All patients received entecavir therapy, and were assigned to TPE group (n = 33) and DPMAS group (n = 27). Primary end-points were the effects of TPE and DPMAS on liver function and serum inflammatory markers.

RESULTS

Serum procalcitonin, interleukin (IL)-6, and high sensitive C-reactive protein (hsCRP) were significantly elevated in patients with HBV-ACLF. TPE achieved significantly higher removal rates of total bilirubin (TBIL, P = .002), direct bilirubin (DBIL, P = .006), and hsCRP (P = .010) than DPMAS, but DPMAS displayed lower loss rate of albumin (P = .000). TPE and DPMAS resulted in similarly increased serum IL-6 levels and comparable 12-week survivals (P > .05). Multivariate analysis showed that hospital stay (Relative Risk [RR]: 1.062, 95% Confidence Interval [CI]: 1.011-1.115, P = .016), prothrombin time (RR: 1.346, 95% CI: 1.077-1.726, P = .010), and international normalized ratio (RR: 0.013, 95% CI: 0.006-0.788, P = .041) were independent predictors for 12-week survival. Both TPE and DPMAS treatments were well-tolerated.

CONCLUSION

Compared to DPMAS, TPE was more efficient in eliminating TBIL, DBIL, and hsCRP, but it was associated with higher loss rate of albumin. TPE and DPMAS were similar in improving 12-week survivals in HBV-ACLF.

Plasma exchange-centered artificial liver support system in hepatitis B virus-related acute-on-chronic liver failure: a nationwide prospective multicenter study in China

BACKGROUND

Plasma exchange (PE)-centered artificial liver support system reduced the high mortality rate of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). But the data were diverse in different medical centers. The present prospective nationwide study was to evaluate the effects of PE on patients with HBV-ACLF at different stages.

METHODS

From December 2009 to December 2011, we evaluated 250 patients at different stages of HBV-ACLF from 10 major medical centers in China. All the laboratory parameters were collected at admission, before and after PE.

RESULTS

Among the 250 patients who underwent 661 rounds of PE, one-month survival rate was 61.6%; 141 (56.4%) showed improvement after PE. Variables such as age (P=0.000), levels of total bilirubin (TB, P=0.000), direct bilirubin (P=0.000), total triglycerides (P=0.000), low-density lipoprotein (P=0.022), Na+ (P=0.014), Cl- (P=0.038), creatinine (Cr, P=0.007), fibrinogen (P=0.000), prothrombin time (PT, P=0.000), white blood cell (P=0.000), platelet (P=0.003) and MELD (P=0.000) were significantly related to prognosis. Multivariate logistic regression analysis showed that age, disease stage, TB, Cr and PT levels were independent risk factors of mortality among HBV-ACLF patients.

CONCLUSIONS

PE can improve the clinical outcome of patients with HBV-ACLF. Levels of TB, Cr and PT, age and disease stage help to predict prognosis.

Comparison of Plasma Exchange With Different Membrane Pore Sizes in the Treatment of Severe Viral Hepatitis

Plasma exchange has become an effective mode of blood purification in patients suffering from liver failure. To assist in patient recovery, we compared two plasma separators to identify a plasma separator with suitable pore sizes to remove toxic substances effectively, and retain important plasma components. The study focused on severe viral hepatitis patients. Of 206 rounds of plasma exchange, 137 were completed with the PS-06 plasma separator (membrane pore size=0.2 microm) and 69 with the EC-4A plasma separator (membrane pore size=0.03 microm). The efficacy of different plasma separators was compared using survival rate, changes in liver biochemistry, immunoglobulin, and complement parameters. The survival rate of patients treated with PS-06 was 43.3% (13 of 30 patients). For patients treated with EC-4A, two patients were bridged to liver transplantation successfully, and 57.9% (11 of 19 patients) survived. In both groups, the levels of total bilirubin, prothrombin time, and bile acid declined significantly. Compared to PS-06, EC-4A could retain significantly larger amounts of immunoglobulin and complements. Our study revealed that plasma exchange implementation with membrane pore size 0.03 microm could remove adequate bilirubin and bile acid, a class of toxins bound to plasma protein in severe viral hepatitis patients, and reduce the loss of essential plasma macromolecules.

Intrasplenic transplantation of encapsulated hepatocytes decreases mortality and improves liver functions in fulminant hepatic failure from 90% partial hepatectomy in rats

BACKGROUND

Encapsulated cell therapy might be a promising approach to enable cell transplantation without immunosuppression. This study investigates the viability and hepatic function of hepatocytes encapsulated with alginate/poly-L-lysine in vitro and the effect of the intrasplenic transplantation of cultured encapsulated hepatocytes on survival in 90% hepatectomized rats as a preliminary step toward allogeneic hepatocyte transplantation without immunosuppression.

MATERIALS AND METHODS

Rat hepatocytes were isolated and encapsulated using alginate/poly-L-lysine. Encapsulated hepatocytes were cultured for 28 days to measure cell viability, liver function, and morphology. Rats were treated with a 90% partial hepatectomy and then immediately underwent the intrasplenic transplantation of the cultured encapsulated hepatocytes, the capsule alone, or the allogeneic hepatocytes without the capsule. The survival rate, liver function, and cell morphology were assessed after transplantation.

RESULTS

The cultured encapsulated hepatocytes maintained their viability and showed better metabolic activity than day 0 cultured encapsulated hepatocytes. The encapsulated cells strongly expressed albumin and were positive for periodic acid-Schiff staining. Electron microscopy demonstrated that the microencapsulated hepatocytes retained the structural elements of hepatic cytoplasm and nuclei. Intrasplenic transplantation of the encapsulated hepatocytes increased the survival rate and improved the hepatic function. Encapsulated hepatocytes transplanted into rat spleen survived well and retained their hepatic function. Moreover, dramatic liver regeneration was observed 48 hr after transplantation in the group that received intrasplenic transplantations of encapsulated hepatocytes.

CONCLUSIONS

The intrasplenic transplantation of cultured encapsulated hepatocytes improved the survival rate of an acute liver failure rat model induced by a 90% partial hepatectomy.