Ducatez Mariette F, Martin Ana Moreno, Owoade Ademola A, Olatoye Isaac O, Alkali Bello R, Maikano Issoufou, Snoeck Chantal J, Sausy Aurelie, Cordioli Paolo, Muller Claude P
Institute of Immunology, National Public Health Laboratory, CRP-Santé, 20A rue Auguste Lumière, L-1950 Luxembourg.
Istituto Zooprofilattico sperimentale della Lombardia e dell'Emilia Romagna, Reparto di virologia e sierologia specializzata, Via Bianchi 9, 25124 Brescia, Italy.
J Gen Virol. 2009 Nov;90(Pt 11):2679-2685. doi: 10.1099/vir.0.012476-0. Epub 2009 Jul 22.
Between 2002 and 2007, more than 1000 chickens from commercial farms, live bird markets and backyard farms in Nigeria and Niger were tested for the presence of the infectious bronchitis virus (IBV) genome. Phylogenetic analysis of full-length sequences of the spike 1 (S1) gene revealed a new genotype of IBV that we refer to as 'IBADAN'. The minimum genetic distance to the closest 'non-IBADAN' strains (UK/7/93 at the nucleotide level; H120 and M41 at the amino acid level) reached 24 and 32 % at the nucleotide and amino acid levels, respectively. The full genome of the IBADAN reference strain (NGA/A116E7/2006) had a genetic distance of 9.7-16.4 % at the nucleotide level with all available fully sequenced strains. As IBV S1 plays a major role in antigenicity, the antigenic relatedness of NGA/A116E7/2006 was compared with strains of other serotypes. NGA/A116E7/2006 did not cross-react with antisera against IT02, M41, D274, Connecticut or 793/B strains in virus neutralization assays. NGA/A116E7/2006 cross-reacted with the QX-like strain ITA/90254/2005 but only to a low level (antigenic relatedness of 33 %), suggesting that IBADAN also represents a new serotype. A comparison of S1 sequences identified several amino acids that may play a role in IBV antigenicity. Despite the absence of obvious clinical signs in poultry infected by IBADAN strains, it is important to test the cross-protection of current vaccine strains.
2002年至2007年期间，对尼日利亚和尼日尔商业农场、活禽市场及后院农场的1000多只鸡进行了检测，以确定是否存在传染性支气管炎病毒（IBV）基因组。对刺突1（S1）基因全长序列进行系统发育分析，发现了一种新的IBV基因型，我们将其称为“伊巴丹型”。与最接近的“非伊巴丹型”毒株（核苷酸水平上的英国/7/93；氨基酸水平上的H120和M41）的最小遗传距离在核苷酸和氨基酸水平上分别达到24%和32%。伊巴丹参考毒株（NGA/A116E7/2006）的全基因组与所有已完全测序的可用毒株在核苷酸水平上的遗传距离为9.7%至16.4%。由于IBV S1在抗原性方面起主要作用，因此将NGA/A116E7/2006的抗原相关性与其他血清型毒株进行了比较。在病毒中和试验中，NGA/A116E7/2006与抗IT02、M41、D274、康涅狄格或793/B毒株的抗血清没有交叉反应。NGA/A116E7/2006与QX样毒株ITA/90254/2005有交叉反应，但程度较低（抗原相关性为33%），这表明伊巴丹型也代表一种新的血清型。对S1序列的比较确定了几个可能在IBV抗原性中起作用的氨基酸。尽管感染伊巴丹型毒株的家禽没有明显的临床症状，但检测当前疫苗毒株的交叉保护作用很重要。
