Morbillivirus Receptors and Tropism: Multiple Pathways for Infection

Sato, Hiroki; Yoneda, Misako; Honda, Tomoyuki; Kai, Chieko

From these observations, it had been postulated that B-cell line-isolated strains do not use the ubiquitously expressed CD46 but utilize another molecule as a receptor (Lecouturier et al., 1996; Buckland and Wild, 1997; Bartz et al., 1998; Hsu et al., 1998; Tanaka et al., 1998; Tatsuo et al., 2000a) . Tatsuo et al. (2000b) performed a screening of a cDNA library of B95a cells, in which a non-susceptible human kidney cell line, 293T, was transfected with the cDNA library and then screened with a vesicular stomatitis virus pseudotype bearing the H protein of MeV isolated from B-cells and F protein from the Edmonston strain. As a result, a single cDNA clone capable of making transfected 293T cells susceptible to MeV-H protein bearing pseudotype was identified. The sequence of the clone was a homolog of signaling lymphocyte activation molecule (SLAM), and consequently, human SLAM was identified as a lymphoid cell receptor for wildtype MeV. Importantly, the Edmonston strain was found to utilize SLAM, in addition to CD46, as a receptor, indicating that SLAM acts as a receptor not only for B-cell line-isolated MeV strains but also for vaccine and laboratory-adapted strains (Tatsuo et al., 2000b) .