Standard immunosuppressive treatment reduces regulatory B cells in children with autoimmune liver disease.

Introduction: Autoimmune hepatitis (AIH) is a chronic liver disease caused by a perturbed immune system. The scarcity of short- and long-term immune monitoring of AIH hampered us to comprehend the interaction between immunosuppressive medication and immune homeostasis. Methods and patients: We recruited children with AIH at the time of diagnosis and at the 1st, 3rd, 6th, 12th, 18th, and 24th months of immunosuppression (IS). We also enrolled children with AIH being on IS for >2 years. Children with drug-induced liver injury (DILI), and those receiving tacrolimus after liver transplantation (LT), were enrolled as disease/IS control subjects. Healthy children (HC) were also recruited. Peripheral blood mononuclear cells (PBMCs) were isolated from all participants. Healthy liver tissue from adult donors and from livers without inflammation were obtained from children with hepatoblastoma. By using flow cytometry, we performed multi-parametric immune profiling of PBMCs and intrahepatic lymphocytes. Additionally, after IS with prednisolone, tacrolimus, rapamycin, or 6-mercaptopurine, we carried out an in vitro cytokine stimulation assay. Finally, a Lifecodes SSO typing kit was used to type HLA-DRB1 and Luminex was used to analyze the results. Results: Untreated AIH patients had lower total CD8 T-cell frequencies than HC, but these cells were more naïve. While the percentage of naïve regulatory T cells (Tregs) (CD4+FOXP3lowCD45RA+) and regulatory B cells (Bregs, CD20+CD24+CD38+) was similar, AIH patients had fewer activated Tregs (CD4+FOXP3highCD45RA - ) compared to HC. Mucosal-associated-invariant-T-cells (MAIT) were also lower in these patients. Following the initiation of IS, the immune profiles demonstrated fluctuations. Bregs frequency decreased substantially at 1 month and did not recover anymore. Additionally, the frequency of intrahepatic Bregs in treated AIH patients was lower, compared to control livers, DILI, and LT patients. Following in vitro IS drugs incubation, only the frequency of IL-10-producing total B-cells increased with tacrolimus and 6MP. Lastly, 70% of AIH patients possessed HLA-DR11, whereas HLA-DR03/DR07/DR13 was present in only some patients. Conclusion: HLA-DR11 was prominent in our AIH cohort. Activated Tregs and MAIT cell frequencies were lower before IS. Importantly, we discovered a previously unrecognized and long-lasting Bregs scarcity in AIH patients after IS. Tacrolimus and 6MP increased IL-10+ B-cells in vitro.

Liver involvement in neuroblastoma amplified sequence gene deficiency is not limited to acute injury: Fibrosis silently continues.

Biallelic mutations in neuroblastoma amplified sequence gene (NBAS) is a rare disease which is characterized by recurrent liver failure (RALF). We reported the novel mutations, clinical characteristics and long-term outcomes of 5 patients with novel biallelic NBAS variants. Four patients (80%) had acute, episodic liver crises (LC) triggered by fever, with a median age of onset of 8.5 months. The median age in the last episode was 34 months. Median number of liver episodes was 4. The course of ALF was complicated by hepatic encephalopathy and hypoglycaemia in all patients with ALF. Two patients recovered with conservative treatment, 2 required liver transplantation (LT) and 1 died during the fourth episode. Long-term post-transplant follow-up showed normal liver function and histology. There is no hepatic or extrahepatic recurrence after LT. Non-transplanted patients exhibited fibrosis in either biopsy or elastography. Despite a reduction in the frequency of clinically significant episodes, patients may exhibit ongoing liver injury and fibrosis. An acute on chronic liver failure with predominant cholestasis can be an alternative presentation.

A novel insight into the pathophysiology of autoimmune hepatitis: An immune activator mutation in the FLT3 receptor.

Autoimmune hepatitis (AIH) is a chronic progressive autoimmune liver disease characterized by hypergammaglobulinemia, interface hepatitis, a female preponderance, and the presence of autoantibodies in most patients. The presence of HLA-DR3/DR4 and functional impairment in regulatory T cells are associated with AIH. However, AIH is a multifactorial complex disease. This report is a description of a case of seronegative AIH in a girl with chronic hepatitis, a high immunoglobulin E (IgE) level, perforating nodular dermatitis, and sheer eosinophilia. To re-evaluate the diagnosis, whole exon sequencing was performed. It was determined that the patient had ancestral haplotype A1-B8-DR3, which is associated with autoimmunity. Importantly, it was also noted that an undocumented point mutation (Ala627Thr) of the FMS-like tyrosine 3 kinase (FLT3) receptor was present. This FLT3 receptor gain-of-function mutation is associated with the activation of the mechanistic target of rapamycin (mTOR), and dendritic cell activation. In addition, a loss-of-function mutation in the melanocortin-3 receptor gene, which inhibits interleukin 4, was detected. The constellation of these immune deregulatory factors may have propagated auto-aggression of the liver, causing chronic hepatitis with AIH features. The findings of seronegativity with eosinophilia and a high IgE level led us to hypothesize that the pathognomonic mechanism in this case was unlike that of classic AIH pathophysiology. Since mTOR is constitutively activated, mTOR inhibitors may be a useful option to treat AIH and dermatitis.

Quantification of Plasma Cell-Free Circulating DNA at Different Stages of Colorectal Cancer.

Cell-free circulating DNAs (cfcDNAs) have been recognized as promising biomarkers for a number of cancers. This study aimed to quantify the cfcDNA in colorectal cancer to assess its potential value as biomarker. Quantification of baseline cfcDNA was determined as the amount of free glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in plasma, using quantitative real-time polymerase chain reaction (PCR). The calculated area under the curve (AUC) of receiver operating characteristic (ROC) for cfcDNA was 0.875 (95% CI, 0.811-0.94), which was indicative of a high discriminatory power (p < 0.001) and significant accuracy in distinguishing cancer patients from healthy individuals. The quantification of cfcDNA could be useful for clinical settings of CRC.

Nucleostemin silencing induces differentiation and potentiates all-trans-retinoic acid effects in human acute promyelocytic leukemia NB4 cells via autophagy.

Here, we report that targeting Nucleostemin (NS), a recently discovered stem cells-enriched gene, by a specific small interference RNA (siNS), decreases the rate of proliferation of acute promyelocytic leukemia (APL) NB4 cells and induces differentiation and autophagy. In addition, NS silencing promotes the effects of all-trans-retinoic acid (ATRA)-based differentiation therapy in NB4 cells. Autophagy inhibitors 3-methyladenine and bafilomycin block the effect of NS targeting on differentiation, indicating a new functional link between NS and autophagy as an important regulator of differentiation in NB4 cells. The capability of NS in modulating autophagy and differentiation, alone or in combination with ATRA, may help to broaden the range of treatment options available to treat leukemia.

Modeling and structural analysis of human Guanine nucleotide-binding protein-like 3,nucleostemin.

Human GNL3 (nucleostemin) is a recently discovered nucleolar protein with pivotal functions in maintaining genomic integrity and determining cell fates of various normal and cancerous stem cells. Recent reports suggest that targeting this GTP-binding protein may have therapeutic value in cancer. Although, sequence analyzing revealed that nucleostemin (NS) comprises 5 permuted GTP-binding motifs, a crystal structure for this protein is missing at Protein Data Bank (PDB). Obviously, any attempt for predicting of NS structure can further our knowledge on its functional sites and subsequently designing molecular inhibitors. Herein, we used bioinformatics tools and could model 262 amino acids of NS (132-393 aa). Initial models were built by MODELLER, refined with Scwrl4 program, and validated with ProsA and Jcsc databases as well as PSVS software. Then, the best quality model was chosen for motif and domain analyzing by Pfam, PROSITE and PRINTS. The final model was visualized by vmd program. This predicted model may pave the way for next studies regarding ligand binding states and interaction sites as well as screening of databases for potential inhibitors.