A Novel Antibody Detection Technique Using the Agglutination of Surface Displaying Yeasts

Blood screening for disease in the developing world remains an enormous challenge despite significant advances in modern biotechnology. Simple, affordable, and easily deployed tools for antibody detection in blood and other fluids are still desperately needed. A simple yeast-based agglutination assay that requires no electricity, no sophisticated equipment, and minimal training is described here, using established methods for displaying stable fusion proteins on the surface of S cerevisiae. Strains displaying peptides with known binding regions for generic human immunoglobulin G antibodies, and for specific human antibodies against T. cruzi (the causative agent for Chagas’ disease) and dengue virus were created and grown. The cells displaying disease epitopes were mixed with the samples positive for the disease antibodies, and have been shown to capture the specific antibodies to their surfaces. After washing, the coated cells were mixed with cells displaying the Z domain derived from S. aureus, which binds to the Fc region of the captured antibodies, linking the cell types together. The links formed between the cell types cause the cells to agglutinate, resulting in positive and negative signals that are easily distinguishable to the naked eye. Factors affecting the agglutination, including ionic strength, cell mass, the geometry of the well, and proper growth conditions were studied to produce a working protocol for the assay. The key strengths of the assay: simplicity, stability, modularity, low cost, low technical requirement, and broad familiarity with similar tests, give it promising potential to be a new alternative to current industry methods.

Department dc:contributor.department

Chemistry

Year dc:date.issued

2018

Author dc:creator

• Kil, Richard

Advisor dc:contributor.advisor

• McMillen, David R

• agglutination
• antibody
• Chagas
• dengue
• diagnostic
• yeast

Handle dc:identifier.uri

http://hdl.handle.net/1807/94909

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/94909