Background Cryptococcus is the most common cause of adult meningitis in Africa. We evaluated the activity of adjunctive sertraline, previously demonstrated to have in vitro and in vivo activity against Cryptococcus. Methods We enrolled 172 HIV-infected Ugandans with cryptococcal meningitis from August 2013 through August 2014 into an open-label dose-finding study to assess safety and microbiologic efficacy. Sertraline 100–400mg/day was added to standard therapy of amphotericin + fluconazole 800mg/day. We evaluated early fungicidal activity via Cryptococcus cerebrospinal fluid (CSF) clearance rate, sertraline pharmacokinetics, and in vitro susceptibility. Findings Participants receiving any sertraline dose averaged a CSF clearance rate of −0·37 (95%CI: −0·41, −0·33) colony forming units (CFU)/mL/day. Incidence of paradoxical immune reconstitution inflammatory syndrome (IRIS) was 5% (2/43) and relapse was 0% through 12-weeks. Sertraline reached steady state concentrations in plasma by day 7, with median steady-state concentrations of 201 ng/mL (IQR, 90–300; n=49) with 200mg/day and 399 ng/mL (IQR, 279–560; n=30) with 400mg/day. Plasma concentrations reached 83% of steady state levels by day 3. The median projected steady state brain tissue concentration at 200mg/day was 3·7 (IQR, 2·0–5·7) mcg/mL and 6·8 (IQR, 4·6–9·7) mcg/mL at 400mg/day. Minimum inhibitory concentrations were ≤2 mcg/mL for 27% (35/128), ≤4 mcg/mL for 84% (108/128), ≤6 mcg/mL for 91% (117/128), and ≤8 mcg/mL for 100% of 128 Cryptococcus isolates. Interpretation Sertraline had faster cryptococcal CSF clearance, decreased IRIS, and decreased relapse compared with historical experiences. Sertraline reaches therapeutic levels in a clinical setting. This inexpensive and off-patent oral medication is a promising adjunctive antifungal therapy. Funding National Institutes of Health, Grand Challenges Canada.

No abstract

Cell therapies, which include bioartificial liver support and hepatocyte transplantation, have emerged as potential treatments for a variety of liver diseases. Acute liver failure (ALF), acute-on-chronic liver failure, and inherited metabolic liver diseases are examples of liver diseases that have been successfully treated with cell therapies at centers around the world. Cell therapies also have the potential for wide application in other liver diseases, including non-inherited liver diseases and liver cancer, and in improving the success of liver transplantation. Here we briefly summarize current concepts of cell therapy for liver diseases.

Hereditary tyrosinemia type I (HT1) is caused by deficiency in fumarylacetoacetate hydrolase (FAH), an enzyme that catalyzes the last step of tyrosine metabolism. The most severe form of the disease presents acutely during infancy, and is characterized by severe liver involvement, most commonly resulting in death if untreated. Generation of FAH+/− pigs was previously accomplished by adeno-associated virus-mediated gene knockout in fibroblasts and somatic cell nuclear transfer. Subsequently, these animals were outbred and crossed to produce the first FAH−/− pigs. FAH-deficiency produced a lethal defect in utero that was corrected by administration of 2-(2-nitro-4-trifluoromethylbenzyol)-1,3 cyclohexanedione (NTBC) throughout pregnancy. Animals on NTBC were phenotypically normal at birth; however, animals were euthanized approximately four weeks after withdrawal of NTBC due to clinical decline and physical examination findings of severe liver injury and encephalopthy consistent with acute liver failure. Biochemical and histological analyses, characterized by diffuse and severe hepatocellular damage, confirmed the diagnosis of severe liver injury. FAH−/− pigs provide the first genetically engineered large animal model of a metabolic liver disorder. Future applications of FAH−/− pigs include discovery research as a large animal model of HT1 and spontaneous acute liver failure, and preclinical testing of efficacy of liver cell therapies, including transplantation of hepatocytes, liver stem cells, and pluripotent stem cell-derived hepatocytes.

Hereditary tyrosinemia type I (HT1) results in hepatic failure, cirrhosis, and hepatocellular carcinoma (HCC) early in childhood and is caused by deficiency in the enzyme fumarylacetoacetate hydrolase (FAH). In a novel approach we used the chimeric adeno-associated virus DJ serotype (AAV-DJ) and homologous recombination to target and disrupt the porcine Fah gene. AAV-DJ is an artificial chimeric AAV vector containing hybrid capsid sequences from three naturally occurring serotypes (AAV2, 8 and 9). The AAV-DJ vector was used to deliver the knockout construct to fetal pig fibroblasts with an average knockout targeting frequencies of 5.4%. Targeted Fah-null heterozygote fibroblasts were used as nuclear donors for somatic cell nuclear transfer (SCNT) to porcine oocytes, and multiple viable Fah-null heterozygote pigs were generated. Fah-null heterozygotes were phenotypically normal, but had decreased Fah transcriptional and enzymatic activity compared to wild-type animals. Conclusion This study is the first to use a recombinant chimeric AAV vector to knockout a gene in porcine fibroblasts for the purpose of SCNT. In using the AAV-DJ vector we observed targeting frequencies that were higher than previously reported with other naturally occurring serotypes. We expect that the subsequent generation of FAH-null homozygote pigs will serve as a significant advancement for translational research in the areas of metabolic liver disease, cirrhosis and HCC.