Analysis of the Proportion of C-terminal K Deletion in Antibodies
Terminal variations of antibody drugs are divided into N-terminal and C-terminal variations. Common N-terminal variations are usually due to incomplete processing of N-terminal signal sequences, resulting in the retention of N-terminal methionine residues or the partial or complete formation of pyroglutamate from N-terminal Glu and Gln residues. Common C-terminal variations include sequence truncation, such as the deletion of the C-terminal Lys residue in monoclonal antibodies, also known as K deletion. These changes in protein termini may occur due to varying fermentation conditions and protein purification buffers. For instance, it has been reported that monoclonal antibodies produced in B-cell hybridomas and those obtained from CHO cell transfections exhibit significant variations in the proportion of C-terminal lysine deletions. Another example is that even minor adjustments to a different monoclonal antibody can also result in significant changes in C-terminal lysine proportions. These are just two common examples. Nevertheless, N- and C-terminal sequencing is a crucial quality control analysis, and C-terminal K deletion determination is mandatory according to the ICH Q6B guidelines for testing biotechnological products. Methods such as IEF, cIEF, ion-exchange chromatography, and LC-MS are commonly used to analyze C-terminal lysine variations. Currently, digesting samples with trypsin followed by LC-MS analysis is a mature and common method for detecting the proportion of C-terminal K deletions in antibodies.
Four types of antibody C-terminal processing
Project report in Chinese/English
In the technical report, Biotyech will provide you with a detailed bilingual technical report in both Chinese and English, which includes:
1. Experimental steps (Chinese and English)
2. Relevant mass spectrometry parameters (Chinese and English)
3. Mass spectrometry images
4. Raw data
5. Information on the proportion of C-terminal K deletion in antibodies
One-stop service for determining the proportion of C-terminal K deletion in antibodies
You just need to place an order and send your samples
Biotyech provides a one-stop service: sample processing, machine analysis, data analysis, and project report
