Biochemical Subtyping of Amyloid in Formalin-Fixed Tissue Samples Confirms and Supplements Immunohistologic Data

Fluorescent in situ hybridization targeting 16S ribosomal RNA was used for specific detection of the obligate intracellular bacterium Lawsonia intracellularis in enterocytes from pigs affected by proliferative enteropathy. A specific oligonucleotide probe was designed and the specificity of the probe was determined by simultaneous comparison with indirect immunofluorescence assay for detection of L. intracellularis in formalin-fixed tissue samples from 15 pigs affected by porcine proliferative enteropathy. We used 10 tissue samples from pigs without proliferative mucosal changes as negative controls. The results showed that the oligonucleotide probe is specific for L. intracellularis and that fluorescent in situ hybridization targeting ribosomal RNA is a suitable and fast method for specific detection and histological recognition of L. intracellularis in formalin-fixed tissue.

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A simple and effective method for inactivating virus infectivity in formalin-fixed tissue samples from patients with Creutzfeldt-Jakob disease

Neurology ◽

10.1212/wnl.40.6.887 ◽

1990 ◽

Vol 40 (6) ◽

pp. 887-887 ◽

Cited By ~ 92

Author(s):

P. Brown ◽

A. Wolff ◽

D. C. Gajdusek

Keyword(s):

Virus Infectivity ◽

Fixed Tissue ◽

Tissue Samples ◽

Formalin Fixed Tissue ◽

Jakob Disease ◽

Formalin Fixed

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Effect of formalin fixation on thermal conductivity of the biological tissue

Journal of Biomechanical Engineering ◽

10.1115/1.4026559 ◽

2014 ◽

Cited By ~ 1

Author(s):

Steven C. Bauserman ◽

Jonathan W. Valvano

Keyword(s):

Thermal Conductivity ◽

Biological Tissues ◽

Formalin Fixation ◽

Fatty Tissue ◽

Fresh Tissue ◽

Fixed Tissue ◽

Tissue Samples ◽

Formalin Fixed Tissue ◽

Formalin Fixed

Effect of formalin fixation on thermal conductivity of the biological tissues is presented. A self-heated thermistor probe was used to measure the tissue thermal conductivity. The thermal conductivity of muscle and fatty tissue samples was measured before the formalin fixation and then 27 hours after formalin fixation. The results indicate that the formalin fixation does not cause a significant change in the tissue thermal conductivity of muscle and fatty tissues. In the clinical setting, tissues removed surgically are often fixed in formalin for subsequent pathological analysis. These results suggest that, in terms of thermal properties, it is equally appropriate to perform in vitro studies in either fresh tissue or formalin-fixed tissue.

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Resin Tissue Microarrays: a Universal Format for Immunohistochemistry

Journal of Histochemistry & Cytochemistry ◽

10.1369/jhc.5c6659.2005 ◽

2005 ◽

Vol 53 (10) ◽

pp. 1189-1197 ◽

Cited By ~ 15

Author(s):

William J. Howat ◽

Anthony Warford ◽

Joanne N. Mitchell ◽

Kay F. Clarke ◽

Jen S. Conquer ◽

...

Keyword(s):

Polyclonal Antibodies ◽

Tissue Microarrays ◽

Single Chain ◽

Fixed Tissue ◽

Tissue Samples ◽

Glycol Methacrylate ◽

Formalin Fixed Tissue ◽

Single Chain Fv ◽

Nuclear Antigens ◽

Formalin Fixed

Tissue microarray (TMA) technology allows the miniaturization and characterization of multiple tissue samples on a single slide and commonly uses formalin-fixed paraffin-embedded (FFPE) tissue or acetone-fixed frozen tissue. The former provides good morphology but can compromise antigenicity, whereas the latter provides compromised morphology with good antigenicity. Here, we report the development of TMAs in glycol methacrylate resin, which combine the advantages of both methods in one embedding format. Freshly collected tissue fixed in -20C acetone or 10% neutral buffered formaldehyde were cored and arrayed into an intermediary medium of 2% agarose before infiltration of the agarose array with glycol methacrylate resin. Acetone-fixed resin TMA demonstrated improved morphology over acetone-fixed frozen TMA, with no loss of antigenicity. Staining for extracellular, cell surface, and nuclear antigens could be realized with monoclonal and polyclonal antibodies as well as with monomeric single-chain Fv preparations. In addition, when compared with FFPE TMA, formalin-fixed tissue in a resin TMA gave enhanced morphology and subcellular detail. Therefore, resin provides a universal format for the construction of TMAs, providing improved tissue morphology while retaining antigenicity, allows thin-section preparation, and could be used to replace preparation of frozen and FFPE TMAs for freshly collected tissue.

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Application of anti-BCG antibody for rapid immunohistochemical detection of bacteria, fungi and protozoa in formalin-fixed paraffin-embedded tissue samples

Acta Veterinaria Hungarica ◽

10.1556/avet.56.2008.1.9 ◽

2008 ◽

Vol 56 (1) ◽

pp. 89-99 ◽

Cited By ~ 8

Author(s):

Levente Szeredi ◽

Róbert Glávits ◽

Miklós Tenk ◽

Szilárd Jánosi

Keyword(s):

Bacterial Species ◽

Histochemical Staining ◽

Fixed Tissue ◽

Tissue Samples ◽

Bacteriological Culture ◽

Formalin Fixed Tissue ◽

Formalin Fixed Paraffin Embedded ◽

Almost All ◽

Formalin Fixed

The applicability of an anti- Mycobacterium bovis (BCG) antibody-based immunohistochemistry (IHC) procedure was investigated using everyday veterinary pathological samples collected from 13 different animal species. Fifty-one formalin-fixed and paraffin-embedded tissue samples were selected for this study. Forty, 4 and 7 tissue samples contained different species of bacteria, fungi and protozoa, respectively. Three serial sections were prepared in each case. Two sections were pre-treated with enzyme and heat, respectively, while the last section was not pre-treated. In seven cases the sensitivity of histochemical staining (HSM), IHC and bacteriological culture were compared. Heating of the sections in a microwave oven was the most effective method in the case of almost all pathogens used. Strong or moderate positive reactions were observed for 26 bacterial species, all fungal and 2 protozoal species, while weak reactions occurred for 2 bacterial and 1 protozoal species. Only 4 protozoal and 12 bacterial species, including Leptospira and all the five Mycoplasma species examined, showed no reaction in this test. IHC had almost the same sensitivity as bacteriological culture and was more sensitive than HSM. The IHC method presented here should be preferred to HSM as a general screening tool in cases where pathological lesions suspicious for infections are evident and no microorganism can be cultured in vitro or only formalin-fixed tissue samples are available for the laboratory examination.

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