Article

Human T-cells recognise N-terminally Fmoc-modified peptide

Autoimmunity and Transplantation Division, The Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, 1G Royal Parade, Parkville, Vic. 3050, Australia.
Vaccine (Impact Factor: 3.49). 09/2003; 21(25-26):3638-46. DOI: 10.1016/S0264-410X(03)00402-X
Source: PubMed

ABSTRACT We aimed to generate T-cell clones specific for human pre-proinsulin. An HLA DQ8, CD4+ T-cell clone that recognised a 10mer (C65-A9) peptide from pre-proinsulin was isolated. Further analysis revealed that the clone responded neither to recombinant proinsulin nor to re-synthesised C65-A9 peptide. Analysis of the original peptide revealed minor contamination (<0.5%) with an N-terminal Fmoc adduct. This peptide was synthesised and shown to stimulate the clone. Thus, Fmoc-modified peptides, which are common contaminants in synthetic peptides, can stimulate human CD4+ T-cells. This finding has important implications for the use of synthetic peptides in screening and epitope mapping studies and their use as vaccines in humans.

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