Rotavirus-like particles (VLPs) expressing VP2 and VP6 (2/6 VLPs), or VP2, VP6 and VP7 (2/6/7 VLPs), were generated by coinfecting Spodoptera frugiperda 9 cells with two or three recombinant baculoviruses, respectively, at a moi $5 plaque forming units per cell, as previously described [84] . Briefly, the baculoviruses expressed RF (bovine rotavirus) VP6, RRV VP7, or a fusion protein consisting of GFP fused to the N terminus of RF VP2 deleted in the first 92 amino acids. Infected cultures were collected 5-7 days post infection and purified by cesium chloride density gradient centrifugation. VLPs composed of RF VP2, SA11 Cl3 VP6, SA11 Cl3 VP7 and SA11 4F VP4 (2/4/6/7 VLPs) were similarly prepared, as previously described [85, 86, 87] . The protein concentration of the purified VLP preparations was estimated by the Bradford method.