We report the electron microscopic structure of an alpha-dystroglycan (alpha-DG) fragment (DGEKFc4) that contains binding sites for lymphocytic choriomeningitis virus (LCMV) and the extracellular matrix (ECM) molecule laminin. In electron microscopic images, DGEKFc4 appears as dumbbell-shaped rods with a length of 7.5 +/- 0.5 nM and width of 3 +/- 0.3 nM. The C-terminal human Fc allows binding of anti-human Fc antibody resulting in formation of immune complexes that preserve alpha-DG binding to virus. Electron microscopy shows the antibody binding to near one end of the dumbbell-shaped rods. Because arenaviruses like LCMV or Lassa fever virus (LFV) generate poor neutralizing antibodies during natural infection or vaccination, we assayed whether the alpha-DG receptoid bodies generated could be used as an efficient antibody mimic. However, the receptor body formed by either alpha-DG fragment alone or complexed to antibody to human Fc failed to efficiently neutralize virus.