Abstract
A hybridoma secreting a human monoclonal autoantibody to the islet cell autoantigen IA-2 was prepared from peripheral lymphocytes of a patient with type 1 diabetes and Graves' disease using EBV infection followed by fusion with a mouse/human hybrid cell line. The monoclonal antibody (M13) is an IgG1/kappa and in an immunofluorescence test M13 at 1 μg/mL showed islet cell antibody reactivity equivalent to 40 JDF units. M13 IgG bound 35S-labelled IA-2 (26% at 100 μg/mL) and 125I-labelled IA-2 (34% at 100 μg/mL) in an immunoprecipitation assay and reacted well with IA-2 in western blotting analysis. Amino acids 777–808 in the PTP domain of IA-2 were found to be important for M13 binding in an analysis using modified 35S-labelled IA-2 proteins. M13 V region genes were from VH1-3, D3-22, JH4b, VKI DPK8/Vd+ and JK3 genes and showed a high replacement/silent mutation ratio for both the heavy (11.0) and the light (6.0) chain genes. Mouse monoclonal antibodies (mMAbs) reactive with at least three different epitopes within IA-2 aa 604–686 corresponding to the juxtamembrane domain were also obtained. F(ab′) 2 or Fab from the mMAbs inhibited serum IA-2 autoantibody binding to IA-2 in 20/22 diabetic sera whereas M13 F(ab′) 2 caused inhibition in only 6/22 sera. M13 is representative of some patient serum IA-2 autoantibodies and as such provides a useful tool to study autoimmune responses to IA-2.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
