Insights into immune evasion of human metapneumovirus: novel 180- and 111-nucleotide duplications within viral G gene throughout 2014-2017 seasons in Barcelona, Spain

Abstract

Highlights HMPV has a prevalence of 3%, affecting equally children and adults. 180- and 111-nucleotide duplications emerged, increasing in prevalence over seasons. G proteins w/ duplications protruded more from the membrane than w/o duplication. Viruses w/ duplications were more associated to LRTI in adults than w/o duplication. These facts suggest these duplications might enhance an immune evasion mechanism

Respiratory syncytial virus B sequence analysis reveals a novel early genotype

“…These observations suggest the occurrence of independent duplication events that, ultimately, resulted in the establishment of a dominant variant leading to the emergence of the BA genotype. This is consistent with previous reports that indicate that more than one duplication event resulted in new variants of human metapneumovirus and RSV-A [34][35][36] .…”

Global Extension and Predominance of Human Metapneumovirus A2 Genotype with Partial G Gene Duplication

“…A study in Italy identified only one A1 genotype virus among 49 children with HMPV infection, while Kong et al identified one case among 145 HMPV infections that were genotyped in China [ 37 , 38 ]. Many recent studies have failed to detect HMPV A1 cases indicating that this genotype might have become extinct [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. The 180-nucleotide duplication in the G gene of HMPV was reported to be present in respiratory samples obtained in 2014 and onward in Japan and Spain [ 7 , 16 ].…”

“…Many recent studies have failed to detect HMPV A1 cases indicating that this genotype might have become extinct [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. The 180-nucleotide duplication in the G gene of HMPV was reported to be present in respiratory samples obtained in 2014 and onward in Japan and Spain [ 7 , 16 ]. Subsequently, the 111-nucleotide duplication in the G gene of HMPV was reported by Saikusa et al in viruses detected in 2017 in Japan [ 17 ].…”

“…Since then, A2b viruses have been shown to cluster in two main clades which have been referred to by different names: A2b1, the clade which includes older sequences and continues to be referred to as A2b by many authors and more recently as A2.2.1; and A2b2, the clade which encompasses most recently isolated viruses, including viruses with partial duplications of the G gene, which is referred to as A2c by many authors, but also referred to as Novel A2 sublineage/Unique A2 sublineage/Unique A2b sublineage and more recently A2.2.2 [ 3 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Of interest, in 2017 HMPV strains with partial duplication of the G gene were described [ 7 , 16 ]. These include two distinct groups of viruses: those with a 111 nt duplication and those with a 180 nt duplication [ 7 , 16 , 17 ].…”

“…Of interest, in 2017 HMPV strains with partial duplication of the G gene were described [ 7 , 16 ]. These include two distinct groups of viruses: those with a 111 nt duplication and those with a 180 nt duplication [ 7 , 16 , 17 ]. Since then, viruses carrying these partial duplications of the G gene have been identified in China, Croatia, and other countries [ 8 , 9 ].…”