Heparin-like glycosaminoglycans prevent the infection of measles virus in SLAM-negative cell lines

The wide tissue tropism of the measles virus (MV) suggests that it involves ubiquitously expressed molecules. We have constructed a recombinant MV expressing the enhanced green fluorescent protein (EGFP) (rMV-EGFP) and demonstrated that the rMV-EGFP infected several cell types (HEK-293, HepG2, Hep3B, Huh7, and WRL68 cells) that do not express the human signalling lymphocyte activation molecule (SLAM), which is known as a cellular receptor for morbilliviruses. MV infection of HEK-293 and HepG2 cells was not inhibited in an infectivity–inhibition assay using an anti-SLAM monoclonal antibody, indicating that MV could infect cells without using SLAM. Soluble heparin (HP) inhibited the rMV-EGFP infectivity in SLAM-negative cell lines in a dose-dependent manner. Direct interaction between purified virions and HP was detected in a surface plasmon resonance assay. We also demonstrated that the hemagglutinin (H) protein, but not the fusion (F) protein is responsible for the interaction between the virions and HP. Taken together, our results suggest that HP-like glycosaminoglycans bind to the H protein of MV and play a key role in the infection of SLAM-negative cells.