Presentation of endogenous acetylcholine receptor antigen to a specific CD4+ T-cell line by a transfected B-cell line.
Currently, the limited supply and stability of some human autoantigens pose formidable difficulties in characterizing patients' T cells specific for them; recombinant preparations may contain bacterial contaminants, and synthetic peptides have arbitrarily chosen start and stop points. In order to provide a stable antigen source with naturally processed epitopes, a full-length acetylcholine receptor (AChR) alpha subunit construct was transfected into B-lymphoblastoid cell lines (B-LCL). Expression was much easier to detect at the mRNA level than the protein level. Nevertheless, this transfectant also stimulated a T-cell line that recognized the alpha 149-156 region in the context of HLA-DR4 at high sensitivity. The responses were specific both for the antigen transfected and for the presenting HLA-DR allele. This study thus confirms the potential of autologous B-LCL expressing natural epitopes in the context of HLA class II molecules for characterizing established T-cell lines, and perhaps also for initiating new ones.
Mulcahy
A F
AF
Department of Medicine, University of Newcastle upon Tyne, UK.
Beeson
D M
DM
Willcox
N
N
Diamond
A G
AG
D001324:Autoantigens / Q000235:genetics*; D001402:B-Lymphocytes / Q000276:immunology; D015152:Blotting, Northern; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D006801:Humans; D007453:Iodide Peroxidase / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011950:Receptors, Cholinergic / Q000235:genetics / Q000276:immunology*; D014162:Transfection
D001324:Autoantigens; D012333:RNA, Messenger; D011950:Receptors, Cholinergic; D007453:Iodide Peroxidase