Binding of influenza type A viruses to group B Streptococcus and haemagglutination by virus-bound bacteria.
We studied the bindings of human influenza A type viruses to group B Streptococcus (GBS), types Ia, II, III and IV, of sialic acid (SA)alpha2-3 linkage, using A/PR/8/34(H1N1) and A/Memphis/1/71(H3N2). The viruses were found to bind to all types of GBS, with the exception of PR/8/34 for GBSII, and to elute from GBSIa, III and IV at 37 degrees C, except GBSII. Electron microscopy confirmed these behaviours of the influenza viruses. The virus-binding capability of GBS types seemed to depend on the side chain length of the terminal SA. Treatment of GBSIa, III and IV, except enzyme-resistant type II, with bacterial neuraminidase resulted in the loss of virus-binding capability of GBS. These findings confirmed that SAalpha2-3 linkage of GBS capsules functions as receptor for human influenza viruses. When singular bacteria were prepared from mainly chain-like GBS with sonication, viruses were found to bind to them more efficiently. Untreated and sonicated GBS were both aggregated with high doses of virus. Furthermore, using A/Memphis/1/71(H3N2) and GBSII, we found that virus-bound GBS, untreated or sonicated, caused haemagglutination (HA). The morphological evidence that chicken erythrocytes were bridged with virus-bound native GBSII, supporting occurrences of HA, was obtained. Statistical analysis suggested that HA by virus-bound sonicated (singular) GBS was mediated by bacteria bound by at least two or three virus particles.
Department of Virology and Immunology, Osaka University of Pharmaceutical Sciences, Takatsuki, Japan. nz6t-hsk@asahi-met.or.jp
Y
Y
Hosaka
A
A
Ikeura
Y
Y
Harada
K
K
Kuroda
H
H
Hamayasu
T
T
Suzuki
K
K
Yamada
Y
Y
Kawase
Y
Y
Suzuki
D000818:Animals; D002240:Carbohydrate Sequence; D004912:Erythrocytes / Q000378:metabolism; D006384:Hemagglutination; D006801:Humans; D009980:Influenza A virus / Q000378:metabolism* / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000737:chemistry / Q000378:metabolism; D009439:Neuraminidase / Q000378:metabolism; D011817:Rabbits; D013010:Sonication; D013292:Streptococcus agalactiae / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure*
D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid