Todd D, Creelan J L, McNulty M S
Veterinary Research Laboratories, Stormont, Belfast, United Kingdom.
J Clin Microbiol. 1991 May;29(5):933-9. doi: 10.1128/jcm.29.5.933-939.1991.
A dot blot hybridization assay capable of detecting chicken anemia agent (CAA)-specific DNA in tissues from infected birds has been developed. The assay uses a 32P-labeled DNA probe prepared from cloned CAA-specific fragments representing the entire virus genome and has a sensitivity limit of between and 1 and 10 pg. DNAs from CAA isolates originating in the Federal Republic of Germany, Japan, the United States, the United Kingdom, and Australia were detected. Investigation of specimens from experimentally infected chicks indicated that virus-specific DNA was detected in the tissues of birds from 5 through 42 days after infection and that greater amounts were usually detected in the thymus than in the spleen, liver, feces, or blood. Tissues from specific-pathogen-free and broiler chicks which had become infected at an older age through contact with experimentally infected anemic chicks also contained CAA-specific DNA detectable by the assay. Thymuses from 1- to 2-week-old chicks from eight commercial broiler flocks which had been showing clinical signs characteristic of anemia-dermatitis syndrome were found positive by the hybridization technique, but thymuses from chicks obtained from broiler flocks which did not show such signs were found negative. Of the 35 positive samples (from 46 samples tested), 19 (54%) contained virus-specific DNA in sufficiently great amounts to permit 4-h autoradiography exposures and sample throughput times of 2 days. When compared with virus isolation, the CAA dot blot hybridization assay is time- and labor-saving.
已开发出一种斑点印迹杂交检测法，可检测感染禽类组织中鸡贫血因子（CAA）特异性DNA。该检测法使用由代表整个病毒基因组的克隆CAA特异性片段制备的32P标记DNA探针，灵敏度极限为1至10皮克。检测到了源自德意志联邦共和国、日本、美国、英国和澳大利亚的CAA分离株的DNA。对实验感染雏鸡的标本进行调查表明，在感染后5至42天的禽类组织中检测到病毒特异性DNA，并且通常在胸腺中检测到的量比在脾脏、肝脏、粪便或血液中更多。通过与实验感染的贫血雏鸡接触而在较大龄时感染的无特定病原体雏鸡和肉鸡雏鸡的组织中也含有可通过该检测法检测到的CAA特异性DNA。通过杂交技术发现，来自八个商业肉鸡群、表现出贫血性皮炎综合征临床特征 的1至2周龄雏鸡的胸腺呈阳性，但从未表现出此类症状的肉鸡群获得的雏鸡的胸腺呈阴性。在35个阳性样本（共检测46个样本）中，19个（54%）含有足够大量的病毒特异性DNA，可进行4小时放射自显影曝光，样本通量时间为2天。与病毒分离相比，CAA斑点印迹杂交检测法省时省力。
