Related Experiment Videos
Studies on selectin-carbohydrate interactions
G S Jacob1, J K Welply, P R Scudder
1Department of Immunology, Searle Discovery Research, Monsanto Company, St. Louis, Missouri 63167, USA.
Advances in Experimental Medicine and Biology
|January 1, 1995
Summary
Multivalent sialyl Lewisx (sLex) conjugated to BSA significantly enhances binding affinity to E-selectin, offering a potent strategy for inhibiting neutrophil recruitment in inflammation.
Area of Science:
- Biochemistry
- Immunology
- Glycoscience
Background:
- Neutrophil recruitment to inflamed endothelium is crucial for immune response.
- This process involves selectin-mediated rolling interactions between neutrophils and endothelial cells.
- Selectins recognize specific carbohydrate structures, with multivalent binding enhancing interaction strength.
Purpose of the Study:
- To investigate the potential of multivalent molecular antagonists to mimic and inhibit selectin-mediated cell-cell interactions.
- To synthesize and test BSA-conjugated forms of sialyl Lewisx (sLex) for enhanced binding affinity to E-selectin.
Main Methods:
- Synthesis of monovalent sLex and its BSA-conjugated forms.
- Testing the inhibitory effects of these compounds on HL-60 cell binding to immobilized E-selectin.
- Measurement of thermodynamic dissociation constants for monovalent sLex:E-selectin interactions.
Main Results:
- BSA-conjugated sLex (sLex-BSA) demonstrated potent, dose-dependent inhibition of HL-60 cell binding to E-selectin.
- sLex16-BSA exhibited a three-order of magnitude enhancement in inhibitory activity compared to free sLex, with an IC50 of 1 microM.
- The thermodynamic dissociation constant for monovalent sLex:E-selectin interaction was determined to be 120 ± 31 microM.
Conclusions:
- Multivalent sLex-BSA exhibits significantly higher affinity for E-selectin than monovalent sLex.
- This enhanced affinity suggests that multivalent glycan structures are effective in inhibiting selectin-mediated cell adhesion.
- These findings support the development of multivalent antagonists for therapeutic intervention in inflammatory diseases.