Isolation Of ALV-A Strains And The Receptor Protein Of ALV-J In Layer Chicken

Since1868avian leukosis was first reported by Roloff, it has been found all of the world. The lymphoid leukosis which was caused by avian leukosis virus (ALV) subgroup A was the most common cancer with low morbidity (i.e.1%-2%), occasionally exceeding20%loss. Avian virus leukosis virus subgroup J (ALV-J) was firstly isolated in1989, which was the recombinant of exogenous ALV and EAV-HP of host endogenous sequence. Recent years, the disease is epidemic in poultry in China, although amount of eliminating ALV plan has been practiced, especially prevalence in layer chicken. In this study, several strains of ALV-A have been isolated and identified the virus complete genome was analyzed. Besides, the receptor of ALV-J in layer chicken was separated by SUJ-IgGFc-Beads.1. Isolation and identification ALV-A strains from layer chickensMonolayer DF1cells were infected with clinic samples for virus isolation at37℃and5%CO2for7days. p27antigen in the supernatant of the DF1cells was detected with P27antigen detection kits. The results showed the supernatant was positive to P27antigen.It is suggested that the ALV was obtained. The gp85gene of ALV was amplified with the primes designed according to the sequences of ALV published in GenBank. The results showed the sequence of the isolated strain was96%homologous with other five ALV-A strains, but82.7%to86.2%homologous with subgroup B. C, D and E strains while only27.5%to31.4%with subgroup J. The complete sequence of the isolate was amplified by PCR. The results indicated the virus is subgroup A.It was found that there were few mutant among the isolated strain and the strains of the subgroup compared with RSA, SDAU09C1, SDAU09C3. The p19was higher mutation rate than p10and p15of gag gene. Besides, gp85was relatively variable.2. Preliminary isolation the receptor protein of ALV-J in layer chickenIn this study, the membrane protein were extracted from the livers and kidneys of SPF chickens with membrane extraction kit. The293cells was used as negative control and DF1cells as positive control. The protein which specially binded with ALV-J SU protein was captured by immunoprecipitation.by the fusion protein SUJ-IgGFc-Beads. The results of SDS-PAGE analysis showed that there were suspected protein in the cell membrane of livers and kidneys of SPF chicken. The molecular weigh of protein is about90KD, which is coincident with I type Na+/H+change proteins(chNHE1) for receptor of HPRS103in DF1cells...