Monoclonal antibody against non-dominant epitopes of HBV e Ag was raised by antigen-antibody co-immunization.

Detection of hepatitis B e antigen (HBeAg) in the sera of individuals infected with hepatitis B virus (HBV) can indicate both a high infectivity of the disease and a poor prognosis of disease treatment. Most of monoclonal antibodies raised against HBV e proteins interact with immuno-dominant epitopes, such as HBeAg-beta. In order to raise antibodies against non-dominant epitopes of HBV e protein, in this study, mice were immunized with both recombinant HBeAg (rHBeAg) and an anti-HBeAg antibody (EWB) recognizing a dominant antigenic epitope of HBeAg (HBeAg-beta epitope).

[Study of the expression membrane protein LASS2].

A human membrane protein LASS2 (Homo sapiens longevity assurance homologue 2 of yeast LAG1), which has important physiologic functions, was expressed in three different expression systems. Only the LASS2 protein carboxyl terminal hydrophilic fragment could be expressed in the prokaryote expression system and its polyclonal antibody was produced. The full length of LASS2 protein could be expressed successfully in both eukaryotic in vitro translation system and Bacuvirus expression system: Bac-to-Bac system.

[HRCA and application in detection of genetically modified plant].

In this article primary studies of the application of hyperbranched rolling cycle amplification (HRCA) in exogenous genes detection of transgenic plants were done. Four padlock probes were designed according to the sequences of four genes/DNA fragments that are used widely in transgenic plants; part of the sequence of pKK233 was chosen as the linking part of padlock probes and a pair of HRCA primers was designed according to the sequence of linking part. Study of the specificity of ligation in HRCA with isotope labeled padlock probes indicated padlock probes could be ringed effectively only when corresponding target DNA exited in the same reaction system and could not be ringed when there was no corresponding target DNA exited.

Molecular cloning, characterisation and tissue-specific expression of human LAG3, a member of the novel Lag1 protein family.

We identified and characterised the cDNA coding for human Lag3, a member of the novel eukaryotic Lag1 protein family which was related to the Saccharomyces cerevisiae longevity-assurance gene LAG1. The composite nucleotide sequence revealed a coding region of 1140 bp, a 5'-UTR of 210 bp and a 3'-UTR of 900 bp. The deduced sequence of 380 amino acids had six transmembrane regions and the conserved Lag1 motif.