Unique Pattern of Intrahepatic T-cell Clonality in Biliary Atresia Livers Versus Intestinal Controls: A Pilot Study.

Biliary atresia (BA) is a rare infantile cholangiopathy of unclear etiology proposed by some to be due to virus-induced autoreactive T-cell-mediated inflammation. The hallmark of T cell activity is clonal expansion of T lymphocytes expressing similar T-cell receptor (TCR) variable regions of the ß-chain. Objective: To test our hypothesis that BA liver tissues would show clonal expansion of 1 or several TCRs. Methods: The complementarity-determining region 3 region of the ß-chain of the TCR was characterized using next-generation sequencing of 7 BA liver samples (age 51 ± 14 days) and 9 intestinal control samples (age 38 ± 16 days). Following sequencing, clonality scores, various VDJ recombinations, total and productive templates, and complementarity-determining region 3 length were measured using the immunoSEQ Analyzer. Results: Next-generation sequencing revealed 1 common TCR rearrangement in 3 BA samples not found in controls. There was a highly diverse TCR population among BA liver and the control samples. The clonality scores ranged from 0.0004 to 0.0062 using a Shannon's entropy score, with numbers close to 0 being highly diverse and numbers close to 1 being highly clonal. The most common TCR VDJ recombinations comprised 1.47-12.9% of the total population of TCR for the BA tissues and 1.05-10.3% for the control samples. Conclusions: Our results show a highly diverse TCR repertoire among all of our samples. However, predominant TCR clonality was not found in any sample. Further studies are required for any possible antigenic triggers responsible for the unique T-cell rearrangements observed in the BA samples.

Hepatitis Vaccines.

Viral hepatitis is a serious health problem all over the world. However, the reduction of the morbidity and mortality due to vaccinations against hepatitis A and hepatitis B has been a major component in the overall reduction in vaccine preventable diseases. We will discuss the epidemiology, vaccine development, and post-vaccination effects of the hepatitis A and B virus. In addition, we discuss attempts to provide hepatitis D vaccine for the 350 million individuals infected with hepatitis B globally. Given the lack of a hepatitis C vaccine, the many challenges facing the production of a hepatitis C vaccine will be shown, along with current and former vaccination trials. As there is no current FDA-approved hepatitis E vaccine, we will present vaccination data that is available in the rest of the world. Finally, we will discuss the existing challenges and questions facing future endeavors for each of the hepatitis viruses, with efforts continuing to focus on dramatically reducing the morbidity and mortality associated with these serious infections of the liver.

In vivo silencing of alpha-synuclein using naked siRNA.

BACKGROUND: Overexpression of alpha-synuclein (SNCA) in families with multiplication mutations causes parkinsonism and subsequent dementia, characterized by diffuse Lewy Body disease post-mortem. Genetic variability in SNCA contributes to risk of idiopathic Parkinson's disease (PD), possibly as a result of overexpression. SNCA downregulation is therefore a valid therapeutic target for PD. RESULTS: We have identified human and murine-specific siRNA molecules which reduce SNCA in vitro. As a proof of concept, we demonstrate that direct infusion of chemically modified (naked), murine-specific siRNA into the hippocampus significantly reduces SNCA levels. Reduction of SNCA in the hippocampus and cortex persists for a minimum of 1 week post-infusion with recovery nearing control levels by 3 weeks post-infusion. CONCLUSION: We have developed naked gene-specific siRNAs that silence expression of SNCA in vivo. This approach may prove beneficial toward our understanding of the endogenous functional equilibrium of SNCA, its role in disease, and eventually as a therapeutic strategy for alpha-synucleinopathies resulting from SNCA overexpression.