Direct Screening of Glycan Patterns from Human Sera: A Selective Glycoprotein Microarray Strategy

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biotechnology

Background:

• Protein glycosylation is a crucial post-translational modification impacting cellular biology.
• Altered glycan patterns are linked to cancer progression and metastasis.
• Direct monitoring of glycoproteins requires efficient immobilization techniques.

Purpose of the Study:

• To develop a boronic acid-tosyl-directed strategy for selective glycoprotein immobilization.
• To optimize strain-promoted alkyne azide cycloaddition (SPAAC) and surface blocking for enhanced microarray performance.
• To establish a glycoprotein microarray platform for analyzing glycan patterns in human serum for cancer diagnostics.

Main Methods:

• Developed a boronic acid (BA)-tosyl-directed immobilization strategy for glycoproteins.
• Optimized SPAAC conjugation chemistry and surface blocking conditions.
• Utilized the optimized platform to analyze glycoprotein lectin-recognition patterns in E. coli lysate, FBS, and human serum samples.

Main Results:

• Successfully immobilized glycoproteins selectively, even with abundant non-glycosylated proteins.
• Achieved enhanced immobilization efficiency and reduced nonspecific absorption through optimized SPAAC and blocking.
• Demonstrated distinguishable glycan patterns differentiating healthy controls from lung and pancreatic cancer patients in serum samples.

Conclusions:

• The developed glycoprotein microarray platform enables direct monitoring of glycan patterns from human sera.
• The technique shows potential as a powerful tool for cancer screening and prediagnosis.
• The optimized immobilization and conjugation chemistry are key to reliable glycan analysis.