title: Structural analysis and immunogenicity of recombinant major envelope protein (rA27L) of buffalopox virus, a zoonotic Indian vaccinia-like virus.
abstract: Buffalopox virus (BPXV), an Indian variant of vaccinia virus (VACV), is a zoonotic agent and affects buffaloes, cattle and humans. A27L is one of the conserved major immuno-dominant envelope proteins of orthopox viruses (OPVs) involved in viral entry/maturation and elicits neutralizing antibodies. In this study, the A27L gene of BPXV-Vij/96 strain encoding recombinant mature A27L (21S to E110) and C-terminal truncated A27L-LZD (21S to N84aa) proteins were cloned and over-expressed in Escherichia coli as fusion proteins. Structurally, A27L of BPXV was similar to that of VACV and found to contain four regions including a potential coiled-coil motif (CCM) in the centre (43 to 84aa). Oligomerization of recombinant A27L fusion protein (∼30 kDa) leads to the formation of dimer/trimers/tetramers under non-reducing conditions. Further, the purified rA27L protein was used for active immunization of rabbit (250 μg/rabbit) and adult mice (10 μg and 50 μg/mice) with or without adjuvants (FCA, alum and CpG). Immune response measured by using indirect-ELISA and SNT revealed a gradual increase in antigen specific serum IgG as well as neutralization antibody titers. Upon challenge with virulent BPXV strain, a protection of 60% was observed in suckling mice passively administered with anti-rA27L sera. No cross-reactivity of rA27L protein with hyperimmune sera against ORFV, GTPV, SPPV, PPRV, FMDV and BTV was noticed in indirect-ELISA. The study indicated that the rA27L protein is a safe and potential prophylactic as well as diagnostic antigen for buffalopox.
authors: Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Regional Campus, Mukteswar 263 138, Nainital, Uttarakhand (UK), India.
authors: Amit
authors: A
authors: Kumar
authors: Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Regional Campus, Mukteswar 263 138, Nainital, Uttarakhand (UK), India.
authors: Revanaiah
authors: R
authors: Yogisharadhya
authors: Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Regional Campus, Mukteswar 263 138, Nainital, Uttarakhand (UK), India. Electronic address: bhanu6467@gmail.com.
authors: Veerakyathappa
authors: V
authors: Bhanuprakash
authors: Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Regional Campus, Mukteswar 263 138, Nainital, Uttarakhand (UK), India.
authors: Gnanavel
authors: G
authors: Venkatesan
authors: Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Regional Campus, Mukteswar 263 138, Nainital, Uttarakhand (UK), India.
authors: Sathish Bhadravati
authors: SB
authors: Shivachandra
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D017124:Conserved Sequence; D007106:Immune Sera / Q000276:immunology; D007114:Immunization; D051379:Mice; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D011817:Rabbits; D011994:Recombinant Proteins; D012680:Sensitivity and Specificity; D014615:Vaccinia / Q000175:diagnosis / Q000276:immunology / Q000473:pathology; D014616:Vaccinia virus / Q000235:genetics / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification
chemical_list: D007106:Immune Sera; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins
keywords: Buffalopox virus; Immunogenicity; Indirect-ELISA; Mouse model; Oligomers; Recombinant A27L protein; Structural analysis