Development and evaluation of an indirect in situ polymerase chain reaction for the detection of porcine circovirus type 2 in formalin-fixed and paraffin-embedded tissue specimens.
Taking advantage of the high sensitivity of polymerase chain reaction (PCR) and the cell-localizing ability of in situ hybridization (ISH), an indirect in situ PCR (ISPCR) method was developed for detecting the distribution of porcine circovirus type 2 (PCV2) in formalin-fixed and paraffin-embedded inguinal lymph nodes obtained from clinically healthy PCV2-carrier pigs and postweaning multisystemic wasting syndrome (PMWS)-affected pigs. Comparisons of the relative sensitivity of indirect ISPCR with other routinely used diagnostic methods for PCV2 indicated that nested PCR was the most sensitive method followed by indirect ISPCR, conventional PCR, ISH, and immunohistochemical (IHC) staining. Although indirect ISPCR, ISH, and IHC staining all revealed a similar signal distribution pattern of PCV2, using indirect ISPCR allowed specific amplification and detection of previously uneasily detected PCV2 signal than by routine ISH or IHC staining, particularly in those cells within the germinal center in clinically healthy PCV2-carrier pigs. Furthermore, six different PCV2 signal expression patterns in conjunction with the correlated lymphoid lesion stages were classified to describe the tissue morphological changes and viral infection. The result indicates that indirect ISPCR is a more effective, cell-based diagnostic tool with good specificity to detect limited PCV2 infection in formalin-fixed and paraffin-embedded tissue specimens and it would be a useful tool for further exploring the pathogenesis of PCV2 infection.
Lin
Chun-Ming
CM
National Taiwan University, Taipei, Taiwan, ROC.
Jeng
Chian-Ren
CR
Hsiao
Shih-Hsuan
SH
Chang
Chih-Cheng
CC
Liu
Chen-Hsuan
CH
Tsai
Yi-Chieh
YC
Chia
Mi-Yuan
MY
Pang
Victor Fei
VF
D000818:Animals; D017925:Circovirus / Q000145:classification* / Q000302:isolation & purification*; D005557:Formaldehyde; D008198:Lymph Nodes / Q000821:virology; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction / Q000662:veterinary*; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000821:virology; D012680:Sensitivity and Specificity; D013552:Swine; D014021:Tissue Preservation / Q000662:veterinary*
D005557:Formaldehyde