Hepatitis B and C in liver transplantation: new strategies to combat the enemies

Fatty acid metabolism constrains Th9 cell differentiation and antitumor immunity via the modulation of retinoic acid receptor signaling

T helper 9 (Th9) cells are interleukin 9 (IL-9)-producing cells that have diverse functions ranging from antitumor immune responses to allergic inflammation. Th9 cells differentiate from naïve CD4+ T cells in the presence of IL-4 and transforming growth factor-beta (TGF-β); however, our understanding of the molecular basis of their differentiation remains incomplete. Previously, we reported that the differentiation of another subset of TGF-β-driven T helper cells, Th17 cells, is highly dependent on de novo lipid biosynthesis. On the basis of these findings, we hypothesized that lipid metabolism may also be important for Th9 cell differentiation. We therefore investigated the differentiation and function of mouse and human Th9 cells in vitro under conditions of pharmacologically or genetically induced deficiency of the intracellular fatty acid content and in vivo in mice genetically deficient in acetyl-CoA carboxylase 1 (ACC1), an important enzyme for fatty acid biosynthesis. Both the inhibition of de novo fatty acid biosynthesis and the deprivation of environmental lipids augmented differentiation and IL-9 production in mouse and human Th9 cells. Mechanistic studies revealed that the increase in Th9 cell differentiation was mediated by the retinoic acid receptor and the TGF-β-SMAD signaling pathways. Upon adoptive transfer, ACC1-inhibited Th9 cells suppressed tumor growth in murine models of melanoma and adenocarcinoma. Together, our findings highlight a novel role of fatty acid metabolism in controlling the differentiation and in vivo functions of Th9 cells.

Switch from intravenous or intramuscular to subcutaneous hepatitis B immunoglobulin: effect on quality of life after liver transplantation

BACKGROUND

Hepatitis B immunoglobulin (HBIG) therapy is available in intravenous (IV) or intra-muscular (IM) formulations. Recently, a subcutaneous (SC) formulation was introduced. This study evaluated changes in quality of life when liver transplant (LT) recipients were switched from IV or IM HBIG to the SC formulation.

METHODS

This multicentre, observational study involved adults who had undergone LT at least 1 year prior to study entry. Quality of life was evaluated using the ITaLi-Q questionnaire, assessing the impact of HBIG therapy on daily activities and patient satisfaction, and the SF-36 Health Survey. Patients completed the questionnaires prior to switching from IV or IM HBIG to SC HBIG and 6 months later.

RESULTS

Eighty-six patients were enrolled; before the switch, 68.6% were receiving IM HBIG and 31.4% IV HBIG. After 6 months, significant improvements in 7 of the 8 ITaLi-Q domains were found, particularly side effects, need for support to adhere to the therapy and satisfaction with the HBIG therapy. Significant improvements in several SF-36 domains were documented, including physical functioning, physical and emotional role limitations, pain, social functioning, physical and mental summary scores.

CONCLUSIONS

The SC route of administration reduces side effects and their interference with daily life, ameliorates negative feelings, and increases patient autonomy.

TH9 cell differentiation, transcriptional control and function in inflammation, autoimmune diseases and cancer

Naïve CD4⁺T cells differentiate into various T cell subsets depending on the specific cytokine environment. T_H9 cells are less well-characterized than other T cell subsets, and factors that control their development and function have only recently been identified. It is now clear that T_H9 cells play critical roles in immune-mediated diseases, including allergic airway, autoimmune and inflammatory bowel diseases, and cancer. Thus, the promotion or suppression of T_H9 cell differentiation, transcriptional control and function may provide novel treatments for clinical inflammation, autoimmune diseases and tumors.

Prophylaxis against Recurrence in Liver Transplantation Patients with Hepatitis B Virus: What is New?

Hepatitis B virus (HBV) causes an endemic infection that affects nearly 2 billion patients worldwide. It is one of the leading causes of liver cirrhosis, hepatocellular carcinoma (HCC), and liver transplantation (LT). Recurrence of HBV infection after LT is due to specific HBV-host genome interactions. Although hepatitis B immunoglobulin treatment constituted the backbone of HBV recurrence, use of the nucleoside and nucleotide analogs (especially the ones with a higher genetic barrier to resistance), either alone or in combination, offer us new and powerful options in overcoming this serious issue.