At 48 h post-transfection, cell lysates were collected by centrifugation at 5000 rpm for 10 minutes, and HA expression was analyzed by Western blotting using anti-H5N1 HA antibodies (ab21297; Abcam). == HA glycosylation patterns and trypsin treatment == To characterize HA glycosylation patterns, 293 cells were harvested following transfection with DNA-HA vectors for 48 h. […]