Anti-CF3CO antibodies, monospecific toward trifluoroacetylated proteins (CF3CO-proteins), which are elicited in experimental animals and humans exposed to the anesthetic agent halothane, cross-react with an unknown protein of approximately 52 kDa, constitutively expressed in tissues of experimental animals and humans not previously exposed to the agent. Using anti-CF3CO antibody, the protein(s) of 52 kDa could be immunoprecipitated from solubilized rat heart homogenate. Two-dimensional gel electrophoretic analysis revealed the presence of distinct major (P1, P2) and minor (P3, P4, P5) protein components with apparent molecular masses of 52 kDa. From each of the components P1 and P2, the amino acid sequences of three peptides were determined and found to exhibit 100% identity with the corresponding amino acid sequences of the E2 subunit of the rat 2-oxoglutarate dehydrogenase complex (OGDC). Additionally to the E2 subunit of OGDC, anti-CF3CO antibody also recognized on immunoblots the purified E2 subunit of the branched chain 2-oxoacid dehydrogenase complex (BCOADC) and protein X, a constituent of the pyruvate dehydrogenase complex (PDC), in a manner sensitive to competition by N6-(trifluoroacetyl)-L-lysine (CF3CO-Lys), 6(RS)-lipoic acid, and N6-(6(RS)-lipoyl)-L-lysine (lipoyl-Lys). Furthermore, a discrete population of autoantibodies was identified in sera of patients with halothane hepatitis which could not discriminate between the lipoylated target epitope present on the E2 subunit of OGDC and epitopes on CF3CO-RSA, used as model for CF3CO-proteins. These data suggest that the autoantigenicity of these proteins in halothane hepatitis is based on the molecular mimicry of CF3CO-Lys by lipoic acid, the prosthetic group common to protein X and the E2 subunits of OGDC and BCOADC.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗

PubMedDate not supplied

The nuclear dry weight of liver cells from patients with virus hepatitis and from controls.

Interferometric investigations were performed at liver cell nuclei isolated in 70 per cent glycerol. In 11 patients with virus hepatitis and seven patients without liver disease the nuclear dry weight of liver cells obtained by liver biopsy was determined by interferometry. The average nuclear dry weight of diploid liver cells from controls was 39.9 pg while an average value of 45.4 pg was found for patients with hepatitis. The corresponding nuclear volumes were 241 and 274mu3 respectively. The dry mass and volume of tetraploid nuclei was twice as big as that of diploid nuclei in both materials. The nuclear water content was neither significantly different between diploid and tetraploid nuclei nor significantly different between nuclei from controls and patients with hepatitis.

Cell Nucleus↗

PubMedDate not supplied

Cytophotometric studies of the DNA, nucleic acid and protein content of human liver cell nuclei.

Cytophotometry was performed on human liver cell nuclei obtained from liver biopsies in 18 patients with normal or practically normal liver histology as judged by light microscopy. Imprints of liver cells and liver cells or liver cell nuclei obtained by different isolation procedures were studied. The nuclear DNA, total nucleic acid and protein content was evaluated after Feulgen, gallocyanin and naphtol-yellow staining and by UV-spectrophotometry. The nuclear area was obtained during the cytophotometric scanning procedure (Zeiss UMSP I). A total of 2,330 nuclei were investigated and approximately 80 per cent of these were diploid. The diploid value was confirmed by UV-spectrophotometry where a total nucleic acid content of approximately 7 pg was found. The nuclei could be grouped in classes corresponding to di-, tetra- and octaploid nuclei, according to their contents of DNA, total nucleic acid and protein and according to their size. The variation in nuclear contents was lowest for DNA with a coefficient of variation of approximately five percent, and highest for the protein content (15 per cent). Within diploid nuclei, insignificant as well as significant correlations between DNA content and size were found, but taken all together a weak positive correlation is likely. Higher correlations were found between nuclear nucleic acid content and size and between nuclear protein content and nuclear size.

Adolescent↗

PubMedDate not supplied

Cytophotometry of feulgen-naphtol yellow S stained liver cells--a computerized method for the calculation of nuclear protein.

A computerized method was developed to calculate the nuclear protein content of Feulgen-Naphtol Yellow S stained liver cells from cytophotometric data. After two consecutive scannings at 570 nm (DNA) and 435 nm (protein), the nuclear localization and shape are defined and nuclear protein is calculated by a method which corrects for the nuclear-cytoplasmic overlap at the nuclear periphery. The results obtained by the procedure are highly reproducible and are in accordance with the results of biochemical determinations of nuclear and total cell protein reported by others.

Animals↗