Vegetable Signatures Derived from Human Urinary Metabolomic Data in Controlled Feeding Studies.

Examination of changes in urinary metabolomic profiles after vegetable ingestion may lead to new methods of assessing plant food intake. To this regard, we developed a proof-of-principle methodology to identify urinary metabolomic signatures for spinach, celery, and onion. Three feeding studies were conducted. In the first study, healthy individuals were fed with spinach, celery, onion, and no vegetables in four separate experiments with pooled urinary samples for metabolite discovery. The same protocol was used to validate the finding at the individual level in the second study and when feeding all three vegetables simultaneously in the third study. An LC-MS-based metabolomics approach was adopted to search for indicative metabolites from urine samples collected during multiple time periods before and after the meal. Consequently, a total of 1, 9, and 3 nonoverlapping urinary metabolites were associated with the intake of spinach, celery, and onion, respectively. The PCA signature of these metabolites followed a similar "time cycle" pattern, which maximized at approximately 2-4 h after intake. In addition, the metabolite profiles for the same vegetable were consistent across samples, regardless of whether it was consumed individually or in combination. The developed methodology along with the identified urinary metabolomic signatures were potential tools for assessing plant food intake.

The immune response induced by hepatitis B virus principal antigens.

Hepatitis B virus (HBV) infection occurs primarily in hepatocytes in the liver with release of infectious virions and non-infectious empty surface antigen particles into the bloodstream. HBV replication is non-cytopathic. Transient infections run a course of several months, and chronic infections are often life-long. Chronic infections can lead to liver failure with cirrhosis and hepatocellular carcinoma. It is generally accepted that neutralizing anti-HBs antibodies plays a key role in recovery from HBV infection by containing the spread of infection in the infected host and facilitating the removal and destruction of viral particles. However, the immune response initiated by the T-cell response to viral antigens is also important for viral clearance and disease pathogenesis in HBV infection. The three structural forms of the viral proteins, the HBsAg, the particulate HBcAg, and the nonparticulate HBeAg, may preferentially elicit different Th cell subsets. The different IgG subclass profiles of anti-HBs, anti-HBc, and anti-HBe in different HBV infection status were revealed. Moreover, the different IgG subclass profiles in chronic carriers did not change with different ALT and AST levels and may reflect the difference between stimulating antigens, immune response, and the stages of viral disease and provide the basis for the use of vaccines and prophylactic treatments for individuals at high risk of human HBV infection. This review elucidates the detailed understanding of the immune responses induced during transient and persistent infection, and the development of immunotherapy and immunodiagnosis in patients with HBV infection, and possible means of reducing the liver damage.