RT Journal Article SR Electronic(1) A1 Sugawara, Kanetsu A1 Kitame, Fumio A1 Nishimura, Hidekazu A1 Nakamura, KiyotoYR 1988 T1 Operational and Topological Analyses of Antigenic Sites on Influenza C Virus Glycoprotein and Their Dependence on Glycosylation JF Journal of General Virology, VO 69 IS 3 SP 537 OP 547 DO https://doi.org/10.1099/0022-1317-69-3-537 PB Microbiology Society, SN 1465-2099, AB Summary In our previous study, seven monoclonal antibodies specific for influenza C virus glycoprotein (gp88) were prepared and tentatively classified into two groups: group A (J14, J9, Q5, K16) has neutralization activity whereas group B (S16, J6, J15) does not. These antibodies were used to analyse the antigenic structure of gp88 and to examine the effect of glycosylation on the antigenicity of the glycoprotein. Operational analysis with a panel of antigenic variants selected with each of the group A antibodies identified two non-overlapping antigenic sites on the gp88 molecules, site A-1 recognized by J14, J9 and Q5 and site A-2 by K16. Sites A-1 and A-2 were shown, however, to be topographically overlapping by competitive binding assays. Competitive binding analysis with group B antibodies identified two additional non-overlapping antigenic sites, site B-1 recognized by S16 and site B-2 by J6 and J15. It was found in radioimmunoprecipitation experiments that antibodies to sites B-1 and B-2 were reactive not only with gp88 but with its non-glycosylated form (T76) synthesized in the presence of tunicamycin. Antibodies to sites A-1 and A-2, in contrast, immunoprecipitated the T76 polypeptide in only trace amounts or not at all. Additionally, Western blot analysis showed that denatured gp88 blotted on nitrocellulose was reactive with antibodies to sites B-1 and B-2 but not with those to sites A-1 and A-2. These observations suggest that glycosylation of gp88 selectively influences the integrity of antigenic sites A-1 and A-2 which are composed of conformation-dependent epitopes., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-69-3-537