Histological demonstration of copper and copper-associated protein in chronic liver diseases.

Abstract

Liver copper concentrations in percutaneous biopsy specimens were measured by neutron activation analysis and compared with histological staining for copper by rubeanic acid and rhodanine, and with copper-associated protein stained by orcein. Liver copper concentrations were elevated in 31 of 35 biopsies from patients with primary biliary cirrhosis (PBC), and discrimination between normal and elevated liver copper was correct in 32 of the 35 biopsies by staining with rubeanic acid, and 31 of the 35 by staining with rhodanine. Orcein staining of copper-associated protein was positive in 33 of the 35 biopsies. All 17 biopsy specimens from patients with Wilson's disease had high liver copper concentrations, but only nine had positive staining for copper, and six were orcein positive. Similarly, histological stains gave little indication of the liver copper concentrations in tissue from 16 patients with chronic active hepatitis. Staining of liver sections can be useful in detecting elevation of liver copper in PBC, but not in Wilson's disease, where the absolute concentration must be measured. Excess copper appears to accumulate in the liver in different chemical forms in PBC and Wilson's disease.

Orcein staining of leukocytes

“…None of our cases was a hepatitis-B-antigen carrier and the staining results obtained with Rhodanine exclude the possibility that the material stained with Orcein in this way is a copper-associated protein. Previous experience with liver tissue has shown that when Orcein stains copper-associated protein, its distribution in cells is almost identical to that obtained with copper stains like Rhodanine (Jain et al, 1978). In granulocytes, positive staining with Rhodanine was obtained in only 3% of cells, while Orcein staining was positive in all cells.…”

Direct visualization of copper-metallothionein in LEC rat kidneys: application of autofluorescence signal of copper-thiolate cluster.

“…These histochemical techniques, however, show a broad specificity in selecting metals. Not only do these detector molecules recognize other divalent cations but they also sometimes fail to detect Cu ions despite the presence of high concentrations of Cu in the tissue (36)(37)(38). The histochemical methods for Cu staining do not always show a good correlation with analytical measurements of the Cu content by immunoreactive staining for MT (35), since only Cu+ bound to MT, not Cuz+ (21)(22)(23)(24)(25).…”

Regional Distribution of Copper, Zinc and Iron in Brain of Wistar Rat Model for Non-Wilsonian Brain Copper Toxicosis

“…However, unlike choroid plexus which stained positively with rhodanine stain, the other brain regions failed to show Cu deposition by rhodanine stain [23], despite increased Cu build up in cortex, hippocampus, striatum and cerebellum. This observation can be explained by the fact that rhodanine stain did not stain positively with tissue sections having Cu concentrations below 0.9 mmol/ kg (&57 lg/g dry weight) [32] and reported conversion factor for calculating wet weight to dry weight of tissues is 3.18 [33]. In addition, no amyloid deposition was seen in any brain region despite the fact that amyloid precursor protein (APP) is a Cu binding protein.…”