Yu et al. Intrathecally synthesized IgG in multiple sclerosis cerebrospinal fluid recognizes identical epitopes over time. J Neuroimmunol. 2011 Nov [Epub]
CSF =cerebrospinal fluid Plasma =blood fluid
Background: Intrathecal antibody production manifest as oligoclonal bands (OCBs) is a hallmark of multiple sclerosis (MS). Once present, OCBs can be detected in the cerebrospinal fluid that bathes the CNS throughout the lifetime of MS patients.
Aim:To determine the specificity of the OCBs, we applied CSF-derived immunoglobulins/antibodie (IgG) obtained from 2 consecutive lumbar punctures of 5 MS patients to screen random peptide libraries (a series of peptides that are the building blocks of proteins) and selected identical and related peptides that reacted with the paired CSF IgGs from each patient.
Results: Antiboies with the OCB reacted with pepetides and immunoblots also showed that these peptides were recognized by OCBs in MS CSF. We further demonstrated that the peptides represented linear epitopes, indicating that they represent natural epitopes of corresponding protein antigens. A database search combined with alanine scan mutagenesis of peptides that bound to CSF IgG from 3 MS patients revealed that they are derived from proteins including serine/threonine-protein kinase, protein ZIP2 and MHC class II (transplantation antigen)
Conclusions: Identification of targets that are recognized by IgG in MS CSF over time provides a critical tool to investigate the specificity of OCBs, which may determine the cause of disease, leading to strategies for diagnostic and therapeutic intervention.
The abilitity to identify what the OCB react to may give clues to the causative agent in MS if we can find they react with viruses, bacteria etc.