A Kinetic Study of Anti-VEGF-A Polyclonal Antibodies and Anti-VEGF-A ssDNA Aptamers

<p>A new detection reagent that could possibly augment or replace antibodies research and diagnosis methods are aptamers. Aptamers are ssDNA, RNA or polypeptide constructs that function like active antibodies. Antibodies and aptamers both specifically bind to selected target molecules, and as such they enable the detection or targeting of the presence or absence of a specific antigen.</p> <p>In order to ensure that ssDNA aptamers perform similarly to antibodies, anti-VEGF-A polyclonal antibody and anti-VEGF-A ssDNA aptamer were evaluated against vascular endothelial growth factor A (VEGF-A) using Surface Plasmon Resonance (SPR). It was hypothesized that the anti-VEGF-A aptamer had the same, if not better, binding kinetics than the anti-VEGF-A polyclonal antibody, and as such offers an ideal replacement for use in in field, real-time testing assays.</p> <p>SPR revealed that both the polyclonal antibody and ssDNA aptamer bound the target antigen, VEGF-A. Additionally, from the SPR kinetic analysis, the anti-VEGF-A aptamer had K_D values of 20-28 nM and the anti-VEGF-A antibody had K_D values of 16-127 uM. The binding efficacy of the aptamer was several orders of magnitude better than that of the antibody. The aptamer was also stable in solution for a longer amount of time than the antibody, which denatured in solution after two weeks.</p>

Name thesis:degree_name

MS in Engineering - Bioengineering

Discipline thesis:degree_discipline

Biomedical and General Engineering

Year dc:date.available

2012

Author dc:creator

• Hedeen, Heather A

Contributors dc:contributor

• David Clague

• VEGF-A
• Aptamer
• Antibodies
• Kinetic analysis
• Surface Plasmon Resonance
• Biomechanics and Biotransport
• Biomedical Devices and Instrumentation
• Other Biomedical Engineering and Bioengineering

Identifier

10.15368/theses.2012.75

OAI identifier oai:identifier

oai:digitalcommons.calpoly.edu:theses-1798