TABLE 2.

Comparison of replicative efficiencies of clinical isolates of human influenza viruses in ST6Gal I-expressing cells versus MDCK cells

Virus typeVirusaYr of isolationAntigenic propertyVirus titer (PFU/ml)bRatio (ST6Gal I titer/MDCK titer)
MDCK cellsST6Gal I-expressing cells
H3N212004A/Fujian/411/2002-like3.9 × 1051.1 × 1062.8
22002A/Panama/2007/99-like6.5 × 1061.7 × 1072.6
32002A/Panama/2007/99-like1.5 × 1062.4 × 10716.0
42002A/Panama/2007/99-like3.4 × 1055.9 × 10617.4
52002A/Panama/2007/99-like1.9 × 1072.5 × 1071.3
62002A/Panama/2007/99-like3.5 × 1064.0 × 1061.1
71995A/Akita/1/94-like6.1 × 1064.9 × 1078.0
81995A/Akita/1/94-like1.2 × 1052.0 × 10616.7
H1N192002A/New Calledonia/20/99-like3.0 × 1051.7 × 1065.7
102002A/New Calledonia/20/99-like1.7 × 1074.8 × 1072.8
112002A/New Calledonia/20/99-like8.5 × 1061.3 × 1071.5
122002A/New Calledonia/20/99-like3.4 × 1067.8 × 10722.9
132002A/New Calledonia/20/99-like4.8 × 1061.8 × 1073.8
142002A/New Calledonia/20/99-like1.5 × 1074.6 × 1073.1
151995A/Yamagata/32/89-like5.7 × 1061.7 × 1073.0
161995A/Yamagata/32/89-like4.8 × 1042.0 × 1054.2
B172003B/Shandong/7/97-like (Victoria)1.3 × 1073.2 × 1072.5
182003B/Shandong/7/97-like (Victoria)1.2 × 1073.7 × 1073.1
192003B/Shandong/7/97-like (Victoria)1.9 × 1083.8 × 1082.0
202003B/Shandong/7/97-like (Victoria)5.3 × 1061.4 × 1072.6
212003B/Shandong/7/97-like (Victoria)1.0 × 1082.7 × 1082.7
221995B/Mie/1/93-like (Yamagata)1.3 × 1082.2 × 1081.7
231995B/Mie/1/93-like (Yamagata)6.4 × 1072.4 × 1083.8
  • a Viruses that had been isolated from clinical specimens using MDCK cells were used for titration in MDCK and ST6Gal I-expressing cells.

  • b The virus titer in each cell line was determined by the plaque assay.