0000000000416613
AUTHOR
Juris Steinbergs
cDNA Synthesis and Cloning
The isolation of intact messenger RNA and its conversion into cDNA copies by avian or Moloney murine reverse transcriptase, as well as subsequent amplification of gene transcripts by the PCR technique, are becoming increasingly important tools in molecular biology. At present, these techniques have been often necessary and widely used for the analysis of individual mRNA levels in cells and tissues by Northern blot analysis, nuclease protection analysis and in situ hybridization. Another important application of RNA templates is the construction of representative cDNA libraries in order to clone genes, to investigate their molecular structure and to express them in prokaryotic and/or eukary…
Molecular Basis for the Interaction of the Hepatitis B Virus Core Antigen with the Surface Immunoglobulin Receptor on Naive B Cells
ABSTRACTThe nucleocapsid of the hepatitis B virus (HBV) is composed of 180 to 240 copies of the HBV core (HBc) protein. HBc antigen (HBcAg) capsids are extremely immunogenic and can activate naive B cells by cross-linking their surface receptors. The molecular basis for the interaction between HBcAg and naive B cells is not known. The functionality of this activation was evidenced in that low concentrations of HBcAg, but not the nonparticulate homologue HBV envelope antigen (HBeAg), could prime naive B cells to produce anti-HBc in vitro with splenocytes from HBcAg- and HBeAg-specific T-cell receptor transgenic mice. The frequency of these HBcAg-binding B cells was estimated by both hybridom…
Short synthetic CDR-peptides forming the antibody combining site of the monoclonal antibody against RNA bacteriophage fr neutralize the phage activity.
The construction of a mouse hybridoma FRS2 secreting neutralizing monoclonal antibody specific for RNA bacteriophages fr, MS2 and GA is reported. The genes encoding the variable domains of the monoclonal antibody FRS2 heavy and light chains were cloned and sequenced and the corresponding complementarity determining region (CDR) peptides were chemically synthesized. The CDR-peptides were tested for their ability to neutralize the activity of RNA phage fr and related RNA phages MS2 and GA. The CDR-derived peptides H2, L2 and L3 interacted with the fr phage particles and neutralized fr phage activity. Two of these peptides-H2 and L3 also had the ability to neutralize partly the activity of rel…