Synthetic Peptides: The Future of Patient Management in Systemic Rheumatic Diseases?

Abstract

Since the first description of self-reactive antibodies in systemic autoimmune rheumatic diseases, many autoantigens have been identified as useful diagnostic biomarkers in clinical immunology. Among the autoantigens, double-stranded desoxoribonucleic acid (dsDNA), the Smith antigen (Sm), topoisomerase-I (topo-I), proliferating cell nuclear antigen (PCNA), and others were described as hallmark targets of systemic autoimmune diseases. The detection of the corresponding autoantibodies can be performed with a variety of immunoassays based on native antigens, recombinant proteins or synthetic peptides. As discussed in this review, synthetic peptides often represent highly accurate antigenic ligands for autoantibody assays that can be easily produced in high quality and quantity and with remarkable reproducibility. Furthermore, the use of peptides that focus on abrogation or neutralization of pathogenic autoantibodies provides a possible new therapeutic approach to the management of autoimmune disorders. There is an increasing number of interesting examples for the application of synthetic peptides in diagnostic approaches. Today's sophisticated epitope mapping methods will potentate the identification of further peptides that can be possibly used as specific targets in diagnostic and therapeutic approaches to improve the patients treatment. This may lead to a new scientific research area with high impact on the development of diagnostic and therapeutic products, to the area of peptide engineering and "theranostics".

Clinical and serological evaluation of a novel CENP-A peptide based ELISA

“…Further, it is well known that it is important to follow patients longitudinally for many years because one autoimmune condition can evolve to another [40] and several studies have reported overlap syndromes of SSc and other diseases such as SLE and RA [41]. Perhaps of more clinical importance, ACA have been reported to precede the diagnosis of SSc and have therefore been proposed as a biomarker to predict the onset of SSc [42,43]. Last but not least, the possibility of physician-based diagnostic error is also a potential complicating factor.…”

Epitope specificity and significance in systemic autoimmune diseases

“…By comparison in SLE, a prototype SARD, more than 150 aAb specificities have been described 13 . Further, some aAbs have been shown to predict the onset of autoimmune conditions for up to decades before full clinical expression, such as anti‐Ro or anti‐double‐stranded DNA (dsDNA) aAbs; 14 others, such as anti‐chromatin, anti‐dsDNA, and anti‐acetylcholine receptor aAbs, are believed to be pathogenic, while there is evidence that some aAbs may be protective against pathogenic processes 15–18 …”

An Anti-Phospholipase A2 Receptor Quantitative Immunoassay and Epitope Analysis in Membranous Nephropathy Reveals Different Antigenic Domains of the Receptor

“…We anticipated that such a new quantitative diagnostic assay might be more representative of the immunological state of the disease, a feature which in turn might benefit patients. To this end, we tested recombinant over-expressed PLA 2 R as a potential target on an addressable laser bead immunoassay (ALBIA) diagnostic platforms and examined overlapping PLA 2 R 15mer peptides representing the full length protein as an approach to identifying a specific epitope which could then be adapted to an improved immunoassay by using smaller peptides [23].…”