DNA aptamers against the receptor binding region of hemagglutinin prevent avian influenza viral infection.

Abstract

The entrance of influenza virus into host cells is facilitated by the attachment of the globular region of viral hemagglutinin to the sialic acid receptors on host cell surfaces. In this study, we have cloned the cDNA fragment encoding the entire globular region (residues 101-257) of hemagglutinin of the H9N2 type avian influenza virus (A/ck/Korea/ms96/96). The protein segment (denoted as the H9 peptide), which was expressed and purified in E. coli, was used for the immunization of BALB/c mice to obtain the anti-H9 antiserum. To identify specific DNA aptamers with high affinity to H9 peptide, we conducted the SELEX method; 19 aptamers were newly isolated. A random mixture of these aptamers showed an increased level of binding affinity to the H9 peptide. The sequence alignment analysis of these aptamers revealed that 6 aptamers have highly conserved consensus sequences. Among these, aptamer C7 showed the highest similarity to the consensus sequences. Therefore, based on the C7 aptamer, we synthesized a new modified aptamer designated as C7-35M. This new aptamer showed strong binding capability to the viral particles. Furthermore, it could prevent MDCK cells from viral infection by strong binding to the viral particles. These results suggest that our aptamers can recognize the hemagglutinin protein of avian influenza virus and inhibit the binding of the virus to target receptors required for the penetration of host cells.

• Authors: Seung Kwan Choi, Changjin Lee, Kwang Soo Lee, Soo-Young Choe, In Pil Mo, Rho Hyun Seong, Seokmann Hong, Sung Ho Jeon
• Journal: Molecules and cells (Mol Cells) Vol. 32 Issue 6 Pg. 527-33 (Dec 2011) ISSN: 0219-1032 [Electronic] Korea (South)
• PMID: 22058017 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antiviral Agents
• Aptamers, Nucleotide
• Hemagglutinins
• Immune Sera
• Peptide Fragments

Topics

• Amino Acid Sequence
• Animals
• Antiviral Agents (chemistry, pharmacology)
• Aptamers, Nucleotide (chemistry, pharmacology)
• Base Sequence
• Cell Line
• Cell Survival
• Cloning, Molecular
• Consensus Sequence
• Dogs
• Hemagglutinins (chemistry, immunology)
• Immune Sera (chemistry)
• Influenza A Virus, H9N2 Subtype
• Mice
• Molecular Sequence Data
• Orthomyxoviridae Infections (prevention & control)
• Peptide Fragments (chemistry, immunology)
• Protein Binding
• Protein Interaction Domains and Motifs
• SELEX Aptamer Technique
• Sequence Analysis, DNA