How HLA binding, antigen processing, T-cell epitope analysis and comparative sequence assessment can support peptide-impurity qualification.
In silico immunogenicity assessment should reflect peptide biology rather than reuse small-molecule QSAR concepts. Sequence-based and antigen-presentation evidence can help identify differences that may change immune recognition.
Sequence representation
The API and impurity should be represented in a way that preserves amino-acid sequence and relevant structural changes.
HLA diversity
Different HLA alleles can recognize different peptide sequences, so population diversity matters.
Global and local comparison
Whole-sequence comparison can be complemented by focused analysis around the modified region.
Integrated endpoints
HLA/MHC binding, processing and T-cell-related endpoints can provide complementary lines of evidence.
Frequently asked questions
Is a small-molecule QSAR model suitable for peptide immunogenicity?
Generally no.
Why evaluate multiple HLA alleles?
Because allele frequencies and binding preferences differ across populations.
What is a T-cell epitope?
A peptide region capable of contributing to T-cell recognition when appropriately presented.
Can in silico assessment replace all experimental work?
No. It supports a weight-of-evidence approach.
