title: Segment-2 sequencing and cross-neutralization studies confirm existence of a neutralization resistant VP2 phenotypic variant of bluetongue virus serotype 1 in India.
abstract: Segment-2 (seg-2) of a bluetongue virus seropype-1 (BTV-1) isolate WGV104/08/Ind of Indian origin was sequenced and its neutralization behavior was studied to understand the antigenic similarity and relationship with other BTV-1 isolates. Multiple alignments of the coding region of seg-2 of WGV104/08/Ind revealed 97.6-99.0% and 97.2-98.4% similarity with other Indian BTV-1 isolates at nucleotide and deduced amino acid sequence level respectively. Several conservative and non-conservative substitutions were observed on the deduced VP2 amino acid sequence of WGV104/08/Ind. Non-conservative substitution of Lys119Glu on the B-cell epitope and Arg330Gly on the neutralizing epitope of VP2 of this isolate was observed. Using isolate-specific heterologous hyperimmune serum (HIS) the phenotypic antigenic relationship (r) was determined between WGV104/08/Ind and other Indian BTV-1 isolates which ranged from 0.092 to 0.208. The relationship score ranged from 0.203 to 0.295 when neutralization behavior of other Indian BTV-1 isolates was studied with the HIS of WGV104/08/Ind. Antigenic similarity (R) between WGV104/08/Ind and other Indian BTV-1 isolates was estimated from a reciprocal cross-neutralization study and ranged from 14.70% to 24.80% indicating existence of major subtype antigenic divergence and neutralization resistant behavior of WGV104/08/Ind.
authors.affiliation: Division of Virology, Indian Veterinary Research Institute, Mukteswar Campus, District Nainital-263 138, Uttarakhand, India.
authors.forename: Sanchay K
authors.initials: SK
authors.lastname: Biswas
authors.affiliation: Division of Virology, Indian Veterinary Research Institute, Mukteswar Campus, District Nainital-263 138, Uttarakhand, India.
authors.forename: Karam
authors.initials: K
authors.lastname: Chand
authors.affiliation: Division of Virology, Indian Veterinary Research Institute, Mukteswar Campus, District Nainital-263 138, Uttarakhand, India.
authors.forename: Waseem
authors.initials: W
authors.lastname: Rehman
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Science, Sri Venkateswara Veterinary University, Rajendranagar, Hyderabad 500030, India.
authors.forename: Yella Narasimha
authors.initials: YN
authors.lastname: Reddy
authors.affiliation: Division of Virology, Indian Veterinary Research Institute, Mukteswar Campus, District Nainital-263 138, Uttarakhand, India. Electronic address: bimalendu.m@gmail.com.
authors.forename: Bimalendu
authors.initials: B
authors.lastname: Mondal
mesh_terms: D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000235:genetics; D001483:Base Sequence; D001820:Bluetongue virus / Q000235:genetics* / Q000276:immunology*; D036022:Capsid Proteins / Q000235:genetics* / Q000276:immunology*; D003429:Cross Reactions; D018985:Epitopes, B-Lymphocyte / Q000235:genetics; D007194:India; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D065288:Serogroup
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D018985:Epitopes, B-Lymphocyte; C442520:VP2 protein, Bluetongue virus
keywords: Antigenic similarity; Bluetongue virus serotype 1; Neutralization resistance; Segment-2; VP2 phenotypic variant