Unmasking the anti-La/SSB response in sera from patients with Sjogren's syndrome by specific blocking of anti-idiotypic antibodies to La/SSB antigenic determinants
Φόρτωση...
Ημερομηνία
Συγγραφείς
Routsias, J. G.
Touloupi, E.
Dotsika, E.
Moulia, A.
Tsikaris, V.
Sakarellos, C.
Sakarellos-Daitsiotis, M.
Moutsopoulos, H. M.
Tzioufas, A. G.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Feinstein Inst Med Res
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Molecular Medicine
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Background: Autoantigen La/SSB is molecular target of humoral autoimmunity in patients with primary Sjogren's Syndrome (pSS) and systemic lupus erythematosus (SLE). in this study, we investigated the existence and possible influence of anti-idiotypic response to anti-La/SSB antibodies. Materials and Methods: Synthetic peptide analogs (pep) of the major antigenic determinants of La/SSB (289-308aa and 349-364aa) were prepared. Based on "molecular recognition" theory, complementary peptides (cpep), derived by anti-parallel readings of the noncoding strand of La/SSB DNA encoding for its antigenic determinants, were constructed. Sera from 150 patients with anti-La/SSB antibodies, 30 patients without anti-La/SSB antibodies, and 42 normal individuals were tested against all four peptides. F(ab')(2) fragments from anti-peptide IgG were prepared and F(ab')(2) - IgG interactions were evaluated using a specific anti-idiotypic ELISA. Results: All four peptides were recognized by anti-La positive sera (83% and 51% for pep and cpep 349-364 and 51% and 28% for pep and cpep289-308, respectively). Anti-cpep F(ab')(2) bound to a common idiotype (Id) located within or spatially close to the antigen combining site of anti La/SSB (anti-pep) antibodies. Homologous and cross-inhibition experiments further confirmed this relation. The anti-idiotypic antibodies inhibited the anti-La/SSB antibody binding to recombinant La/SSB by 91%. To overcome the anti-idiotypic interference in anti-La/SSB detection, a specific assay was developed. Sera were heated for dissociation of Id-anti-Id complexes, anti-Id antibodies blocked with cpep, and anti-La/SSB reactivity was recovered. Application of this method to anti-Ro positive-anti-La/SSB "negative" sera showed that all anti-Ro/SSA positive autoimmune sera also possess anti-La/SSB antibodies. This reaction was not observed in 14 anti-Ro negative- anti-Sm/RNP positive sera from patients with SLE. Conclusions: Autoimmune sera from patients with pSS and SLE contain anti-idiotypic antibodies targeting a common anti-La/SSB idiotype. These antibodies can be detected using complementary peptides of La/SSB epitopes. The antiidiotypic antibodies mask the anti-La/SSB response. Hidden anti-La/SSB antibodies can be released and detected using complementary epitope analogs.
Περιγραφή
Λέξεις-κλειδιά
t-cell determinants, linked-immunosorbent-assay, la ss-b, complementary peptide, f(ab')2 fragments, genetic-code, autoantibodies, autoantigen, recognition, protein
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000178088000001
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας