scholarly journals Optimal Probe Size and Fixation Time for the Detection of Porcine Circovirus–2 DNA by in Situ Hybridization in Formalin-Fixed, Paraffin-Embedded Tissue

2009 ◽  
Vol 21 (5) ◽  
pp. 649-654 ◽  
Author(s):  
Yooncheol Ha ◽  
Chanhee Chae

Probe size and fixation time for detecting Porcine circovirus–2 (PCV–2) by in situ hybridization in formalin-fixed, paraffin-embedded lymph nodes from experimentally infected pigs were optimized. In situ hybridization using a 169–base pair (bp) probe detected significantly fewer PCV–2–positive cells than when using 8 other larger probes ( P < 0.05). The difference in hybridization intensity between smaller probes (169 and 225 bp) and larger probes (416, 473, 571, 631, 693, and 753 bp) was statistically significant ( P < 0.05). The PCV–2–positive cells were consistently detected in lymph nodes fixed up to 3 days; thereafter, the number of positive cells declined. The PCV–2–positive cells were detected in lymph nodes fixed for up to 730 days. The difference in hybridization intensity between samples fixed for a short term (1 or 3 days) and a longer term (4–730 days) was statistically significant ( P < 0.05). The data demonstrates that the optimal probe size and fixation time for detecting PCV–2 in formalin-fixed, paraffin-embedded lymph nodes is 473 bp and 1–3 days, respectively.

1991 ◽  
Vol 39 (1) ◽  
pp. 145-150 ◽  
Author(s):  
E R Unger ◽  
M L Hammer ◽  
M L Chenggis

Colorimetric in situ hybridization is a method of potential importance in diagnosis and research. The largest criticism of the method has been a perceived loss of sensitivity compared with autoradiographic techniques. Our more positive experience with automation of colorimetric in situ hybridization led us to undertake a direct comparison of the sensitivity of 35S- and biotin-labeled probes. Serial sections of formalin-fixed, paraffin-embedded cell pellets from four human cervical carcinoma cell lines with known copies of HPV (CaSki, 400-600 copies HPV 16; HeLa, 10-50 copies HPV 18; SiHa, 1-2 copies HPV 16; HTB31, no known copies HPV) were hybridized with protocols optimized for autoradiographic or colorimetric detection. Both methods gave comparable results, with differences in each technique seen at the limits of sensitivity. The 1-2 copies of HPV 16 per SiHa cell can be detected with both methods; however, grain counting is required for interpretation of the autoradiographic result. This degree of sensitivity for colorimetric in situ hybridization in formalin-fixed, paraffin-embedded material is achieved through careful optimization of probe size and labeling, adequate tissue digestion, and removal of background. Autoradiography may be preferred in situations where quantitation is required, but colorimetric detection retains the advantages of speed, potential for automation, and improved localization of signal with comparable sensitivity.


2018 ◽  
Vol 54 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Joon Im ◽  
Derek P. Burney ◽  
Sean P. McDonough ◽  
Brigid Nicholson ◽  
Adam Eatroff ◽  
...  

ABSTRACT This case report describes the detection of intrahepatic bacteria in formalin-fixed paraffin-embedded histopathological sections from three dogs with neutrophilic, pyogranulomatous, or lymphoplasmacytic hepatitis and cholangiohepatitis. In each of these cases, eubacterial fluorescence in situ hybridization enabled colocalization of intrahepatic bacteria with neutrophilic and granulomatous inflammation in samples that were negative for bacteria when evaluated by routine hematoxylin and eosin histopathology augmented with histochemical stains. Positive responses to antimicrobial therapy were observed in of 2 out of 2 patients that were treated with antimicrobials. These findings suggest that eubacterial fluorescence in situ hybridization analysis of formalin-fixed paraffin-embedded histopathological sections is more sensitive than conventional histochemical stains for the diagnosis of bacteria-associated canine hepatitis.


1995 ◽  
Vol 52 (3) ◽  
pp. 309-316 ◽  
Author(s):  
Yoshito Eizuru ◽  
Yoichi Minamishima ◽  
Tadashi Matsumoto ◽  
Toshinari Hamakado ◽  
Mikio Mizukoshi ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document