Volume 44/1998 No.6
Guest Editorial
Fifty Years of Immunological Tolerance
P. J. BAKER1, T. HRABA2 ...........................189
1National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
2Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Corresponding author: Tomáš Hraba, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Flemingovo n. 2, CZ-166 37 Prague 6, Czech Republic.
Articles
Infection-Activated T Lymphocytes Resist Nitric Oxide Mediated Immunosuppression in the Course of Francisella tularensis 15L Experimental Infection
M. HAJDÚCH1, R. NEMÈEK2, P. VÍTEK3, A. MACELA3, H. KOVÁØOVÁ3
...............193
1Laboratory of Experimental Medicine, Department of Paediatrics, Faculty of Medicine, Palacký University, and Faculty Hospital in Olomouc, Olomouc, Czech Republic
2Department of Analytical and Organic Chemistry, Faculty of Sciences, Palacký University, Olomouc, Czech Republic
3Department of Immunology and Microbiology, Military Academy of J. E. Purkynì, branch in Tìchonín, Tìchonín, Czech Republic
Corresponding author: Marián Hajdúch, Laboratory of Experimental Medicine, Department of Paediatrics, Faculty of Medicine, Palacký University, and Faculty Hospital in Olomouc, Puškinova 6, 775 20 Olomouc, Czech Republic. Tel. 0042-068-585 4401; Fax. 0042-68-585 2505; e-mail marian@tunw.risc.upol.cz.
Abstract.
Transferrin Receptor Expression Is Controlled Differently by Transferrin-Bound and Non-transferrin Iron in Human Cells
K. KRIEGERBECKOVÁ1, V. RICHARDSON1, L. DÖPPER-BRUNNER2, P. CHIBA2, L. C. KÜHN3, H. GOLDENBERG2, J. KOVÁØ1.....201
1Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
2Department of Medical Chemistry, University of Vienna, Vienna, Austria
3Swiss Institute for Experimental Cancer Research, Epalinges s/Lausanne, Switzerland
Corresponding author: Jan Kováø, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Vídeòská 1083, 142 20 Prague 4, Czech Republic. Fax 420 2 4713443; Tel. 420 2 4752637; e-mail: kovar@biomed.cas.cz.
Abstract.
Effects of Ethinylestradiol--Norethisterone Acetate Combinations on the Ultrastructure of Liver, Kidney, Ovary and Endometrium Cells
P. CZEKAJ1, G. NOWACZYK-DURA1, V. CISZKOWA2......207
1Department of Histology and Embryology, Silesian Medical Academy, Katowice, Poland
2IV Department of Obstetrics and Gynaecology, Silesian Medical Academy, Tychy, Poland
Corresponding author: Piotr Czekaj, II Department of Histology and Embryology, Silesian Medical Academy, Medyków 20, 40-757 Katowice, Poland.
Abstract.
Influence of Dietary Supplementation with Olive Oil on Pyroglutamyl-ß-naphthylamide Hydrolysing Activity in Serum and Different Tissues of Mice
J. M. MARTÍNEZ, M. J. RAMÍREZ, I. PRIETO, F. ALBA, M. RAMÍREZ...213
Unit of Physiology, Faculty of Experimental Sciences, University of Jaén, Jaén, Spain .
Corresponding author: José Manuel Martínez Martos, Unit of Physiology, Faculty of Experimental Sciences, University of Jaén, Paraje 'Las Lagunillas' s/n, E-23071, Jaén, Spain. Tel. +34 953 21 23 02; Fax +34 953 21 21 41; e-mail: jmmartos@ujaen.es.
Abstract.
Short Communication
Prednisolone-induced Alteration in Hepatic and Muscular Protein and Glycogen Level: its Correlation with Blood Glucose Level in Mice
R. KARMAKAR1, S. GHATAK1, A. HAIDER1, S. BHATTACHARYA1, S. N. KUNDU2..........217
1Department of Pharmaceutical Technology, Division of Biochemistry, Jadavpur University, Calcutta, India
2Cell Biology and Immunology Laboratory, Department of Zoology, University of Kalyani, Kalyani, Nadia, West Bengal, India
Corresponding author: R. Karmakar, Department of Pharmaceutical Technology, Division of Biochemistry, Jadavpur University, P.O.Box 17028, Calcutta 700 032, India.
Abstract.
Meeting Review
Cells in the Spotlight of Cancer Research
MICHAEL A. SHEARD...............221
Masaryk Memorial Cancer Institute, Žlutý kopec, Brno, Czech Republic
Corresponding author: Michael A. Sheard, Masaryk Memorial Cancer Institute, Žlutý kopec 7, 656 53 Brno, Czech Republic. Fax (420) 5-4321-1169; e-mail: sheard@mou.cz.
Articles
Infection-Activated T Lymphocytes Resist Nitric Oxide Mediated Immunosuppression in the Course of Francisella tularensis 15L Experimental Infection
M. HAJDÚCH1, R. NEMÈEK2, P. VÍTEK3, A. MACELA3, H. KOVÁØOVÁ3
Study of the inhibition of splenocyte proliferation stimulated by concanavalin A (Con A), induced by Francisella tularensis 15L infection, showed that immunosuppression is mediated by nitric oxide (NO). A certain fraction of cells, however, resists the antiproliferative activities of NO and these were characterized as Thy-1.2 positive infection-activated T lymphocytes. The importance of this phenomenon for the development of specific anti-infectious immunity was studied further in naturally resistant and susceptible mouse strains. The naturally resistant mouse strain (C57BL/10) was characterized by early production of NO and depressed splenocyte responsiveness to the mitogen. Early production of NO prevented activation of certain fractions of T lymphocytes. Hence the antibodies of these animals were only directed against three main F. tularensis antigens. Late or reduced release of NO from activated macrophages of susceptible strains (C3H/He and BALB/c) on the other hand was accompanied by late or reduced immunosuppression. This resulted in polyclonal activation of the immune system because the antibodies of these mice reacted with 6--12 compounds of the tularaemic antigen. The difference in heterogeneity of specific antibodies was not caused by a defect in the clonal network as similarly responded both the susceptible and resistant strains to inactivated F. tularensis antigen.
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Transferrin Receptor Expression Is Controlled Differently by Transferrin-Bound and Non-transferrin Iron in Human Cells
K. KRIEGERBECKOVÁ1, V. RICHARDSON1, L. DÖPPER-BRUNNER2, P. CHIBA2, L. C. KÜHN3, H. GOLDENBERG2, J. KOVÁØ1
We studied the effects of iron supplied as transferrin-bound iron and iron supplied as non-transferrin iron on transferrin receptor expression by human cell lines. Defined iron supply conditions were represented by (i) 5 Þg/ml of iron-saturated transferrin (transferrin medium) and by (ii) 500 ÞM ferric citrate (ferric citrate medium). Transferrin receptor expression of studied cell lines (HeLa, K562, Jiyoye) grown as long-term cultures in transferrin medium was somewhat higher (up to 137% of the mean fluorescence intensity) than in ferric citrate medium. The receptor expression corresponded with cellular iron regulatory protein (IRP) activity (ratio activated/total), which was also higher in transferrin medium (0.69--0.84) than in ferric citrate medium (0.33--0.60). However, unexpectedly much higher (about 65--135-fold) cellular iron levels were found in ferric citrate medium (13.9--14.9 nmol/106 cells) than in transferrin medium (0.11--0.21 nmol/106 cells). In contrast to the iron levels, cellular ferritin levels of the cells in ferric citrate medium (38.3--130 ng/106 cells) were only about 2--7-fold higher than in transferrin medium (6.8--61.5 ng/106 cells). We suggest that iron supplied as non-transferrin iron (ferric citrate) is apparently less available for the control of transferrin receptor expression via IRP activity than iron supplied as transferrin.
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Effects of Ethinylestradiol--Norethisterone Acetate Combinations on the Ultrastructure of Liver, Kidney, Ovary and Endometrium Cells
P. CZEKAJ1, G. NOWACZYK-DURA1, V. CISZKOWA2
Sexually mature female Wistar rats were given 0.05 mg ethinylestradiol (EE) + 0.5 mg norethisterone acetate (NET), or 0.1 mg EE + 1.0 mg NET for 6 or 12 sexual cycles, i.e., for 30 or 60 days. Rat hepatocytes, renal proximal tubule cells, ovarian granulosa cells and endometrial gland cells showed ultrastructural changes that correlated with the dose and duration of EE/NET treatment. The most common ultrastructural features were as follows: reduced RER, mitochondrial damage, and an increased number of lysosomes. The study has shown that EE/NET combinations used in oral contraception produce ultrastructural lesions which may impair protein biosynthesis and energy production processes, and may simultaneously enhance cellular catabolism.
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Influence of Dietary Supplementation with Olive Oil on Pyroglutamyl-ß-naphthylamide Hydrolysing Activity in Serum and Different Tissues of Mice
J. M. MARTÍNEZ, M. J. RAMÍREZ, I. PRIETO, F. ALBA, M. RAMÍREZ
Pyroglutamyl aminopeptidase is an omega peptidase which removes pyroglutamyl N-terminal residues from peptides and arylamide derivatives. To date, three distint types of this enzyme have been described and called serum thyroliberinase, cytosolic pyroglutamyl aminopeptidase type I and membrane-bound pyroglutamyl aminopeptidase type II. The activity of all of them is thought to be involved in the regulation, more or less restricted in their substrate specificity, of various susceptible endogenous substrates such as TRH, GnRH, neurotensin, bombesin and anorexogenic peptide. It is well known that the type and amount of fat in the diet modify not only blood lipid concentrations, including cholesterol levels, but changes in cell membrane lipid composition induced by dietary fat supplementation have also been described. Modifications in the composition and physical properties of the membrane lead to alterations in the activities of membrane-bound enzymes and carriers. The aim of this work has been to compare the effect of a standard diet and a high fat diet (olive oil, 20% wt/wt) on pyroglutamyl-ß-naphthylamide hydrolysing activity, in serum and soluble and membrane bound fractions from different tissues of male mice. After ten weeks of feeding, pyroglutamyl-ß-naphthylamide hydrolysing activity was measured fluorometrically using pyroglutamyl-ß-naphthylamide as substrate. Mice fed the high fat diet had higher rates of body weight than controls from the second week of feeding. Serum total cholesterol concentrations were higher after feeding the high fat diet than after feeding the control diet. In serum, no changes were observed in the high fat group. In selected tissues, only pyroglutamyl-ß-naphthylamide hydrolysing activity was modified significantly in the soluble fraction, but not in the membrane bound one, decreasing in the adrenal gland of high fat fed animals. The results may reflect functional modifications in susceptible endogenous substrates.
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Short Communication
Prednisolone-induced Alteration in Hepatic and Muscular Protein and Glycogen Level: its Correlation with Blood Glucose Level in Mice
R. KARMAKAR1, S. GHATAK1, A. HAIDER1, S. BHATTACHARYA1, S. N. KUNDU2
Prednisolone, a potent glucocorticoid, is well known for its immunosuppressive effects on animals. A single dose of 100 Þg, 200 Þg and 300 Þg prednisolone/kg body weight was administered in Swiss albino male mice. Seven days after treatment, the animals were sacrificed to investigate the effect of prednisolone on hepatic and muscular protein contents and glycogen levels along with the level of blood glucose. A catabolic effect on the protein level was evidenced but at the same time the mice became hypoglycemic.
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