AA肉种鸡内源性类ALV-J gp85基因及其抗原表位的分析

Analysis of avian endogenous ALV-J gp85-like gene and its epitope in AA meat-type broiler breeder

利用ALV-J gp85基因两侧的序列片段为引物,从山东潍坊某肉种鸡场送检的7日龄肉种鸡基因组中完整地扩增了内源性类ALV-J gp85基因。利用ALV-J env基因特异性引物不能扩增出长度为2.2kb的目的片段,用ALV-J特异性单抗JE-9做间接免疫荧光检测,也呈现阴性反应。这种内源性类ALV-J gp85基因与已报道的禽内源性反录病毒EAV-HP序列的同源性为85.6%～93.8%,其中与ADOL 0系来航鸡EAV-HP的相似性最高(93.8%)。所得到的内源性类ALV-J gp85基因与外源性ALV-J毒株HPRS-103、SD07LK1、NX0101的同源性分别为93.8%、91.8%和91.7%。并且与外源性ALV-J gp85基因具有相似的Jameson-Worlf抗原表位优势。这种内源性类gp85基因很可能与肉雏鸡早期感染ALV-J后所呈现的免疫耐受现象有关。

primers corresponding to the nucleotide sequences flanking the ALV-J gp85 gene were used to amplify the intact endogenous gp85-like gene from 7-day-old AA meat-type broiler breeder collected in Weifang region,Shandong province.The isolate strain was negative reaction in polymerase chain reaction with specific primers of ALV-J env gene and gave no reaction in indirect fluorescence antibody assay（IFA）with ALV-J specific monoclonal antibody JE-9.The endogenous ALV-J gp85-like gene had 85.6% to 93.8% homology with the endogenous avian retrovirus haemangiopericytoma（EAV-HP） sequences reported,the similarity with env gene in chicken embryo fibroblasts Line 0 EAV-HP was the highest（93.8%）.The endogenous ALV-J gp85-like elements demonstrated 93.8%,91.8% and 91.7% identical to strains HPRS-103、SD07LK1、 NX0101 ALV-J.Antigenic index analysis indicated that ALV-J gp85-like of meat-type broiler breeder was highly similar to that of exogenous ALV-J.The endogenous ALV-J gp85-like gene may play an important role in immunological tolerance of chick after infected with ALV-J.