against Norovirus Genogroup I and II: Recognition of a 2

Abstract 2 Norovirus, which belongs to the family Caliciviridae , is one of the major causes of 3 nonbacterial acute gastroenteritis in the world. Main human noroviruses are of 4 genogroup (G) I and II, which were subdivided further into at least 15 and 18 genotypes 5 (GI/1-15 and GII/1-18), respectively. The development of immunological diagnosis for 6 norovirus had been hindered by the antigen-specificity of the polyclonal antibody. 7 Therefore, several laboratories have produced broad reactive monoclonal antibodies, 8 which recognize the linear GI and II-cross-reactive epitopes or the conformational GI-9 specific epitope. In this study, we characterized novel monoclonal antibody 14-1 10 (MAb14-1) for further development of the rapid immunochromatography test. Our 11 results demonstrated that MAb14-1 could recognize 15 recombinant virus-like particles 12 (GI/1, 4, 8, and 11 and, GII/1-7 and 12-15) and showed weak affinity to the virus-like 13 particle of GI/3. This recognition range is the broadest of the existing monoclonal 14 antibodies. The epitope for MAb14-1 was identified by fragment, sequence, structural, 15 and mutational analyses. Both terminal antigenic regions (amino acid positions 418-426 16 and 526-534) on the C-terminal P1 domain formed the conformational epitope and were 17 in the proximity of the insertion region (427-525). These regions contained 6 18 antigenicities responsible amino acids conserved among genogroup(s), genus, and 19