Immunosuppressive drugs affect interferon (IFN)-γ and programmed cell death 1 (PD-1) kinetics in patients with newly diagnosed autoimmune hepatitis.

Autoimmune hepatitis (AIH) is characterized by overwhelming effector immune responses associated with defective regulatory T cells (Tregs ). Several lines of evidence indicate CD4 as the main effectors involved in autoimmune liver damage. Herein we investigate the in-vitro effects of prednisolone, 6-mercaptopurine, cyclosporin, tacrolimus, mycophenolic acid (MPA) and rapamycin, immunosuppressive drugs (ISDs) used in AIH treatment, on the expression of proinflammatory cytokines, co-inhibitory molecules and ability to proliferate of CD4+ CD25- cells, isolated from the peripheral blood of treatment-naive patients with AIH. We note that in healthy subjects (HS) following polyclonal stimulation and in the absence of ISDs, the expression of interferon (IFN)-γ, interleukin (IL)-17 and tumour necrosis factor (TNF)-α by CD4 effectors peaks at 48 h and decreases at 96 h to reach baseline levels. In contrast, in AIH the expression of all these proinflammatory cytokines continue rising between 48 and 96 h. Levels of programmed cell death-1 (PD-1), T cell immunoglobulin and mucin domain-containing molecule-3 (TIM-3) and cytotoxic T lymphocyte antigen-4 (CTLA-4) increase over 96-h culture both in HS and AIH, although with faster kinetics in the latter. Exposure to ISDs contains IFN-γ and PD-1 expression in AIH, where control over CD4+ CD25- cell proliferation is also noted upon exposure to MPA. Treatment with tacrolimus and cyclosporin render CD4+ CD25- cells more susceptible to Treg control. Collectively, our data indicate that in treatment-naive patients with AIH, all ISDs restrain T helper type 1 (Th1) cells and modulate PD-1 expression. Furthermore, they suggest that tacrolimus and cyclosporin may ameliorate effector cell responsiveness to Tregs .

Review article: the modern management of autoimmune hepatitis.

BACKGROUND: The management of autoimmune hepatitis (AIH) continues to be refined. However, several issues remain unresolved, primarily as a consequence of the low incidence of the disease. This factor has contributed both to a lack of understanding of and a paucity of large scale clinical trials involving therapeutic agents. AIM: To summarize the latest evidence regarding the pathogenesis, diagnosis, therapy and long-term management of AIH with a focus on clinical aspects of the disease. METHOD: We searched PUBMED for articles pertaining to AIH, its pathogenesis, treatment and clinical outcomes, combined with the authors' own knowledge of the literature. RESULTS: Standard therapy (corticosteroids and azathioprine) is effective in more than 80% of patients which renders study of novel agents difficult. Budesonide appears to show equivalence to prednisolone. Available, but limited, data suggest that mycophenolate mofetil, tacrolimus and ciclosporin are all variably effective second line agents. Patients with AIH and cirrhosis are at risk of hepatocellular carcinoma (HCC) and require screening. Patients with end stage liver disease represent excellent candidates for liver transplantation. CONCLUSIONS: Despite ongoing limitations in the understanding of pathogenesis and difficulties in evaluating novel therapies, the management of AIH continues to evolve slowly. Multi-centre collaboration is necessary to obtain sufficient patient numbers to undertake good quality therapeutic studies.