SELPLG and infection: We have also demonstrated that some EV71 strains (PSGL-1–binding strain; EV71-PB) use PSGL-1 as the primary and functional receptor for infection of Jurkat T cells, but other EV71 strains (PSGL-1–non-binding strain; EV71-non-PB) do not, suggesting phenotypic differences in PSGL-1 usage among EV71 strains.