Month: December 2023

To evaluate glycan epitopes of therapeutic IgG1 mAbs, FDA has developed a new lectin microarray with 9 kinds of lectins, and has demonstrated its effectiveness for high-throughput glycan profiling analysis using GlycoStation Reader 2300 (GSR2300) .
https://www.fda.gov/media/169026/download
2023 FDA Science Forum

The new lectin microarray (IgG1-mAb-LecChip) developed by FDA immobilizes 9 kinds of lectins: rPhosL, rOTH3, RCA120, rMan2, MAL_I, rPSL1a, PHAE, rMOA, and PHEL, and uses a standard 14 wells LecChip format.
Glycan analysis of IgG1 mAbs can be performed using lectin microarrays without creaving glycans, making it possible to perform high-throughput glycan profiling analysis from intact IgG1.
FDA has recommended pharmaceutical companies to use IgG1-mAb-LecChip and GlycoStation to facilitate high-throughput glycan profiling analysis when developing IgG1 mAbs to assess batch-to-batch or biosimilar-to-innovator glycan epitopes.

The figure below shows how IgG1-mAb-LecChip, which was optimized for IgG1 glycan analysis, was developed using GlycoStation and LecChip (n=74 library).

As an example of showing the effectiveness of this technology, the figure below shows the result of evaluating the differences in glycosylation between Infliximab and its biosimilar using IgG1-mAB-LecChip and GSR2300. It can be clearly seen that there are significant differences in the abundance of High Mannose structure, sialic acid modification, and triantennary N-glycans.

A group from School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, UK, etc. has reported about a new DDS using glycan-lectin interactions and photodynamic therapy.
https://pubs.rsc.org/en/content/articlelanding/2023/NA/D3NA00544E

Lectin expression can be altered in diseased-state cells.
For example, in cancer the glycan–protein interactions play key roles in avoiding immunosurveillance and reattachment to new tissue during metastasis.
Cancer cells are also associated with increased metabolism due to their unregulated, increased growth, reflected in an increase of glycan transporters.
For breast cancer cells, there are key lectins and glycan-binding receptors that are upregulated, which include galectins, glucose transporters, and the mannose receptor.

PAA-glycans and an amine derivate of the photosensitiser chlorin e6 were chemically attached onto Au nanoparticles as a new DDS.
PAA-glycans act as targeting molecules onto the target cancer cells, and the photosensitiser releases cytotoxic reactive oxygen species upon activation with light of a specific wavelength to kill cancer cells.