Recombinant antibodies derived from laser captured single plasma cells of multiple sclerosis brain identified phage peptides which may be used as tools for characterizing intrathecal IgG response.Kennedy PGE, Graner MW, Walker D, Pointon T, Fringuello A, Yu X.J Neuroimmunol.2020 Jul 14;347:577319. doi: 10.1016/j.jneuroim.2020.577319. Online ahead of print.
Oligoclonal bands and increased IgG antibody levels can be detected in the cerebrospinal fluid in vast majority of patients with Multiple Sclerosis (MS). However, the antigenic specificity of oligoclonal IgG has yet to be determined. Using laser capture microdissection, we isolated single CD38+ plasma cells from lesion areas in two autopsy MS brains, and generated three recombinant antibodies (rAbs) from clonally expanded plasma cells. Panning phage-displayed random peptide libraries was carried out to determine peptide antigen specificities of these MS brain rAbs. We identified 25 high affinity phage peptides from which 5 peptides are unique. Database searches revealed that they shared sequence homologies with Epstein-Barr nuclear antigens 4 and 6, as well as with other viral proteins. Significantly, these peptides were recognized by intrathecal IgG and oligoclonal IgG bands in other MS patients. Our results demonstrate that functional recombinant antibodies can be generated from clonally expanded plasma cells in MS brain lesions by laser capture microdissection, and that these MS brain rAbs have the potential for determining the targets of intrathecal IgG and oligoclonal bands.
ProfG will be pleased that this study finds anti-EBV specific antibodis in the CNS.
However, I take issue that the specficity of oligoclonal bandshas yet to be determined. It has been done numerous times and nothing consistent has been found. On the whole they are not myelin reactive. Sometimes they find antibodies reactive with proteins from insidee cells.
However, these cells in this study were taken from sections. The technology is there to get the sequnces of individual B and T cell receptors from individual cells to address these questions