title: Diagnosis of porcine circovirus type 2 infection with a combination of immunomagnetic beads, single-domain antibody, and fluorescent quantum dot probes.
abstract: The use of a specific antibody conjugated with nanobeads, forming immunomagnetic nanobeads (IMNBs), has been demonstrated to be useful for the capture and detection of viruses. In this study, IMNBs functionalized with a single-domain antibody against the capsid protein (Cap) of porcine circovirus type 2 (PCV2), hereafter denoted as psdAb, were evaluated and used to capture PCV2. Quantum dots (QDs) conjugated with psdAb were used as a fluorescence probe to visualize PCV2 captured by IMNBs. The specificity and sensitivity of this method were further evaluated using common pathogens of pig viral disease and PCV2. To assess its practicality, clinical samples were tested in this study. The results showed that 2.57 ± 0.13 mg Cap or 0.97 ± 0.064 × 10(6) copies of PCV2 particles could be captured by 1 mg of IMNBs in 30 min. This suggests that the IMNBs have the ability to efficiently capture PCV2 with good specificity, as there was no cross-reaction with other pathogens, and with strong sensitivity, with a detection limit as low as 10(3) copies/ml of PCV2 particles. Moreover, PCV2 in inguinal lymph node, lung, spleen, serum, and fecal samples was successfully detected by IMNBs. The results demonstrate that this method is promising for the rapid and effective detection of PCV2 in complex clinical samples.
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Yanchangbu, Lanzhou, 730046, Gansu, China, yangshunli@caas.cn.
authors.forename: Shunli
authors.initials: S
authors.lastname: Yang
authors.forename: Youjun
authors.initials: Y
authors.lastname: Shang
authors.forename: Di
authors.initials: D
authors.lastname: Wang
authors.forename: Shuanghui
authors.initials: S
authors.lastname: Yin
authors.forename: Jianping
authors.initials: J
authors.lastname: Cai
authors.forename: Xiangtao
authors.initials: X
authors.lastname: Liu
mesh_terms: D000825:Animal Structures / Q000821:virology; D000818:Animals; D000914:Antibodies, Viral; D001826:Body Fluids / Q000821:virology; D018173:Circoviridae Infections / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D017925:Circovirus / Q000302:isolation & purification*; D019411:Clinical Laboratory Techniques / Q000379:methods; D018189:Immunomagnetic Separation / Q000379:methods*; D045663:Quantum Dots; D012680:Sensitivity and Specificity; D061905:Single-Domain Antibodies; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis* / Q000821:virology; D014730:Veterinary Medicine / Q000379:methods
chemical_list: D000914:Antibodies, Viral; D061905:Single-Domain Antibodies