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Z Wojtkowiak

Publications and source records attributed to Z Wojtkowiak.

11 recordsLinked to original sources
PubMed1990

Hamster liver chromatin immunospecific non-histone proteins.

Three antisera were prepared against non-histone protein classes named NHCP1, NHCP2 and dehistonized chromatin (with different affinity to DNA) from hamster liver. Two main antigenic bands of MW 17,000 and 36,000 were specific in the NHCP1 fraction and one antigen of MW 56,000 was specific for the NHCP2 fraction from nuclease-sensitive and especially nuclease-resistant chromatin. Other NHCP2 liver antigens of MW 22,000, 27,000, 30,000, 36,000, 37,000, 40,000, 45,000, 46,000, 51,000, 98,000 and 100,000 were present only in nuclease-resistant chromatin of hamster liver. Immunologically specific hamster liver non-histone proteins within the NHCP1 and NHCP2 fractions seem to be restricted to nuclease-resistant chromatin fraction of this tissue. The above mentioned liver specific antigens are absent or present only at trace amounts in analogous Kirkman-Robbins hepatoma fractions.

Animals↗
PubMed1990

Identification of a nuclear antigen with molecular weight of 48,000 differentially expressed in tumour and normal cells.

A non-histone protein with mol. wt of 48,000 differentially expressed in normal and tumour cells was identified using immunological criteria. Antibodies were raised against a component specific for Kirkman-Robbins hepatoma of mol. wt about 48,000 separated from hepatoma non-histone proteins by preparative electrophoresis in polyacrylamide gel. It was demonstrated by immunoblotting that Morris hepatoma 7777 and Ehrlich ascites cells share an antigenic non-histone protein with Kirman-Robbins hepatoma. Tumour cells when compared with normal cells, i.e. hamster and rat liver, are characterized by significant enrichment of this component. Intracellular distribution of the polypeptide with mol. wt 48,000 suggests that this component may be a structural protein the biosynthesis of which increases or the antigenic determinants of which change in tumour cells.

Animals↗
PubMed1990

Cellular distribution of the hamster liver specific nucleolar antigens.

The immunochemical localization of hamster liver nucleolar antigens in subcellular fractions (nuclei, 10,000 x g pellet, 100,000 x g pellet and supernatant), nuclear substructures (chromatin, nuclear matrix, nuclear envelope, nucleoli, RNP particles and nucleosomes), and three classes of nonhistone chromosomal proteins with different affinities to DNA (NHCP1, NHCP2 and NHCP3) from nuclease-sensitive and nuclease-resistant chromatin fractions of hamster liver were studied. Six main nucleolar antigens with mol. wts 27,000; 29,000; 30,000; 36,000; 45,000; and 46,000 were found in subcellular fractions, nuclear substructures and classes of non-histone proteins of hamster liver. The antigens with mol.wts of approx. 27,000; 29,000; and 36,000 which were absent in hamster pancreas, spleen and Kirkman--Robbins hepatoma nuclei, seem specific for liver tissue.

Animals↗
PubMed1988

The granulocyte factor abrogates the alloantigen-induced delayed type hypersensitivity suppression in mice.

Adherent granulocytes secrete granulocyte factor (GF) in the course of the first 60 min of adherence. GF abolishes suppressor cell generation in mice induced by intravenous injection of irradiated allogeneic lymphoid cells. The effect of such induced suppressors was measured in delayed type hypersensitivity reaction induced by subcutaneously injected irradiated allogeneic spleen cells and evaluated in the foodpad test. Suppressor cell induction or GF treatment had no effect on antigen- or phytohaemagglutinin-induced production of migration inhibitory factor.

Animals↗
PubMed1985

Crosslinking of chromosomal antigen common in human tumors to DNA by cis-diamminedichloroplatinum (II).

The antisera specific for dehistonized HeLa cell chromatin were obtained by injecting rabbits or goats. Treatment of chromatin with cis-DDP crosslinked the active proteins to DNA thus preventing dissociation of the proteins in a high salt environment. Immunochemical staining of electrophoretically separated chromosomal proteins transferred to nitrocellulose sheets revealed that cis-DDP among others crosslinked the protein with m.w. of about 81 000. This protein is the only major protein antigen presented in several human tumors and absent in normal human tissues.

Antigens, Neoplasm↗
PubMed1985

Chicken erythrocyte chromatin and nuclear envelope antigens.

Chromatin and inner layer nuclear envelope were isolated from chicken erythrocyte nuclei. Two antisera against dehistonized chromatin and nuclear envelope of chicken erythrocytes were obtained. Using the antiserum against dehistonized chromatin of erythrocytes we found: the presence of the antigens at approximate mol. wts of 56,000 and 77,000 tightly bound with DNA and characteristic of only erythrocyte chromatin; localized antigens at approximate mol. wts of 63,000, 68,000 and 92,000 tightly bound with DNA and common only for chromatin and nuclear envelope of chicken erythrocytes; heterogeneity of the antigens tightly bound with DNA. Using the antiserum against inner layer nuclear envelope we did not find antigens specific only for nuclear envelope and absent in erythrocyte chromatin. Some of the antigens were present in the control preparations of chicken liver chromatin and may be regarded as being species specific.

Animals↗
PubMed1983

Ca2+ Mg2+ -ATPase activity of synaptosome fraction and synaptosomal membranes from different areas of rat brain.

1. Crude synaptosomal fractions obtained from four areas of rat brain were studied; cerebral cortex, hippocampus, midbrain, thalamus with hypothalamus, using the Cotman & Matthews method (1971) Biochim, biophys. Acta 249, 350-394. 2. The purity of synaptosomal fractions was controlled by electron microscopy, and by determination of some marker enzymes such as: LDH, MAO, AChE and cytochrome-c oxidase. 3. Synaptosomes were disrupted by hypoosmotical shock. 4. Crude synaptosomal membrane preparations indicated on increased Ca2+ Mg2+ -ATPase activity in comparison to the activity of this enzyme in synaptosomal fractions. 5. The incubation of crude synaptosomal membranes with cAMP and theophylline caused the subsequent increase of Ca2+ Mg2+ -ATPase activity, but mainly, in hippocampal region.

Acetylcholinesterase↗
PubMed1983

Nuclear localization of lactoferrin in the human granulocyte: Artifact incurred during slide preparation.

Within the blood cells, lactoferrin is found only in the late stage neutrophilic granulocytes. Lactoferrin first appears in these cells during the myelocyte stage of development coincidentally with the specific or secondary granules. Most investigators report a cytoplasmic immunocytochemical localization reaction within the granulocyte. However, others have observed a prominent nuclear localization reaction. Treating the cells with certain fixatives was shown to prevent the relocation of lactoferrin from the cytoplasm to the nucleus when the localization was done on granulocytes prepared by smearing. The present study demonstrated that the relocation of lactoferrin is only a problem when cells were smeared or cytocentrifuged onto slides or fractionated for the purpose of isolating cellular organelles. Under these conditions the selection of fixative is an important consideration. Exposing isolated lactoferrin to a fixative effective in retaining lactoferrin in the cytoplasm of granulocytes smeared on slides did not alter a number of its physical properties. The results suggest that maintenance of the normal cytoarchitecture or effect of fixative on other cellular components prevents the relocation of lactoferrin within the cell during tissue processing and the direct action of fixation on lactoferrin is probably not responsible for this effect.

Acetone↗
PubMed1982

A nuclear matrix antigen HeLa and other human malignant cells.

Antisera were obtained in rabbits to preparations of dehistonized chromatin from HeLa cells. By complement fixation assays, the antisera reacted with HeLa cell chromatin but only marginally with human placenta chromatin. The complement-fixing reactivity of the antisera was inversely related to the amount of dehistonized chromatin used for immunization. Immunochemical staining of electrophoretically separated chromosomal proteins transferred to nitrocellulose sheets revealed numerous antigens in chromatin preparations from several human tumors, placenta, and normal kidney. While immunoabsorption of the antisera with placenta chromatin removed some of the immunochemical staining, many of the electrophoretically separated antigens resisted repeated immunoabsorptions. However, further comparisons revealed that only one major protein antigen (band at an approximate molecular weight of 81,000) was represented in all the assayed human tumors while being absent from human placenta or kidney. Fractionation of HeLa cells into three cytoplasmic and several nuclear fractions showed that almost all the antigens recognized by antisera to dehistonized chromatin were nuclear. The antigenic protein with an approximately molecular weight of 81,000 was found associated with the nuclear matrix fraction.

Antigens↗