Clinical validation of the “in silico” prediction of immunogenicity of a human recombinant therapeutic protein

Abstract

Antibodies elicited by protein therapeutics can cause serious side effects in humans. We studied immunogenicity of a recombinant fusion protein (FPX) consisting of two identical, biologically active, peptides attached to human Fc fragment. EpiMatrix, an in silico epitope-mapping tool, predicted promiscuous T-cell epitope(s) within the 14-amino-acid carboxy-terminal region of the peptide portion of FPX. On administration of FPX in 76 healthy human subjects, 37% developed antibodies after a single injection. A memory T-cell response against the above carboxy-terminus of the peptide was observed in antibody-positive but not in antibody-negative subjects. Promiscuity of the predicted T-cell epitope(s) was confirmed by representation of all common HLA alleles in antibody-positive subjects. As predicted by EpiMatrix, HLA haplotype DRB1*0701/1501 was associated with the highest T-cell and antibody response. In conclusion, in silico prediction can be successfully used to identify Class II restricted T-cell epitopes within therapeutic proteins and predict immunogenicity thereof in humans.

Beyond CDR-grafting: Structure-guided humanization of framework and CDR regions of an anti-myostatin antibody

“…S1). 42,43 The RK35 antibody was selected for humanization to reduce this potential risk. The framework template selection was based upon sequence similarity to close human germline sequences, as well as homology to clinically validated germline sequences.…”

Peptibodies: A flexible alternative format to antibodies

“…In silico T-helper epitope prediction highlighted a 14 amino-acid stretch in the carboxy-terminus of the bioactive peptide as a potential promiscuous immunogenic epitope for a broad range of HLA alleles. 29 Confirming the prediction, a memory T-cell response against the peptide was detected in antibody-positive subjects, but not in antibody-negative subjects, thus providing clinical validation for the in silico epitope prediction tool and hope that in the future such immunogenicity issues can be eliminated at an early stage of lead selection.…”

Auditing Protein Therapeutics Management by Professional APCs: Toward Prevention of Immune Responses against Therapeutic Proteins

“…Clinical validation of an in silico-based prediction has been observed when a recombinant fusion protein was administered to human volunteers and an Ab-mediated immune response was studied (42). EpiMatrix software predicted promiscuous T cell epitope(s) on the protein and 37% of the subjects elicited Ab response.…”