Effect of Staphylococcus aureus serine proteinase on human lymphocyte impairment

Assessment of lymphocyte surface membrane integrity by means of trypan exclusion test and longer term survival studies based on 3HTdR uptake and Con A stimulation test were used to estimate effect of Staphylococcus aureus serine proteinase on human lymphocytes in vitro. At concentration of proteinase as high as 10 micrograms/ml, the percentage of trypan-stained lymphocytes increase with enzyme level. In contrast, decrease of 3HTdR level and Con A stimulation is already apparent at concentrations of proteinase ten times lower. Autologous serum exerts strong protective effect. Observed impairment is discussed as significant for local response in inflammation.     

Rooperol, an inhibitor of cytokine synthesis, decreases the respiratory burst in human and rat leukocytes and macrophages

Luminol-enhanced chemiluminescence was measured in fresh whole human blood, or human neutrophils isolated from heparinized blood, human alveolar macrophages and rat alveolar macrophages stimulated with bacterial endotoxin (LPS). Tetraacetate esters of rooperol, a dicatechol showing anticytokine activity, added to cells simultaneously with LPS inhibited the respiratory burst. The effective concentrations of rooperol were in the range of 1-10 muM depending on cell type and corresponded well with inhibition of nitric oxide production by rat alveolar macrophages. Thus rooperol may reduce some effects of excessive phagocytic activity and inflammatory reaction but by quenching free radicals production may also diminish the resistance to bacterial infections.     

Sodium orthovanadate exerts influence on liver Golgi complexes from control and streptozotocin-diabetic rats

The paper presents the effect of one-week 3mM sodium orthovanadate (Na3VO4) oral treatment of control and streptozotocin[STZ]-diabetic rats. The body weight decreased as compared with untreated control (C group) in both vanadate treated groups (C + V and D + V) and in diabetic untreated rats (D group)--in all cases p < 0.01. A similar tendency was demonstrated by the weight of the livers, which was statistically significant lower than in the controls (p < 0.01). The fluid and food intake were lower in comparison with control vanadium treated groups, in D + V as compared with D it was limited, however, not achieved control level. A high mortality rate, approx. 67%, after the administration of streptozotocin and vanadate (D + V group) was noted; such result had never been previously found within all study groups of rats. But the surviving rats show very good decreased (60%) free blood sugar levels, however euglycaemia was not achieved. The activity of galactosyltransferase, the Golgi complex marker enzyme in group D, was statistically lower than the controls (p < 0.001). Treatment of STZ-diabetic rats with orthovanadate did not increase the enzyme activity toward control level, in both diabetic groups (treated and untreated with Na3VO4) similar dispersion of individual results was found. Morphological study demonstrated, for the first time, no larger cellular lesion in C + V group. The Golgi complex was well developed; showed several cisterns at the trans side, which were grossly distended and contained electron-lucid floccular material. In D + V group typical, cylindrical forms of Golgi complexes predominated. These structures consisted of 3-4 almost practically non-distended cisterns. Also in this case, large, electron-dense vesicles were noted in the vicinity. In this group, small in size, myelin-like structures were also found. These structures might indicate a relatively small, but nevertheless clear damage of the internal membrane system. The external cistern of the cylindrical forms of Golgi complexes, which corresponded the trans side, was often markedly distended and formed a vacuole-like structure filled with electron lucent material; the structure itself sometimes looked empty. Multi-vesicular structures were observed also in this case, but they were seen much more rarely.     

Evaluation of biocompatibility of apatite-wollastonite ceramics in fibroblast cultures

The aim of this work has been to test the biocompatibility of four bioactive, gel derived glass-ceramic materials of CaO-PO2-SiO2 system, modified by addition of boron, aluminum and magnesium compounds. We have examined the growth, collagen synthesis, adhesion and morphology of NRK rat fibroblasts cultured in direct and indirect contact with biomaterials. The growth of cells cultures has been quantified by two methods: [3H]thymidine incorporation and direct counting of cells. The level of collagen synthesis has been used as a parameter describing metabolic activity of cells. Cellular morphology has been assessed following 24 h and 4 days of culturing cells on biomaterials by using SEM and confocal microscopy, respectively. Additionally, in order to obtain information about the attachment of cells to substratum the presence of focal contacts has been examined. The results of all the experiments have demonstrated that none of the materials under study significantly altered cellular functions that were tested. This indicates that additions of MgO, Al2O3 and B2O3 have not induced cytotoxicity of the materials under study. This qualifies them for further in vivo experiments.     

EPR studies of iso-1-cytochrome c: effect of temperature on two-component spectra of spin label attached to cysteine at positions 102 and 47

Wild-type iso-1-cytochrome c from Saccharomyces cerevisiae containing naturally occurring cysteine at position 102 and mutated protein S47C (derived from the protein in which C102 had been replaced by threonine) were labeled with cysteine-specific methanethiosulfonate spin label. Continuous wave (CW) electron paramagnetic resonance (EPR) was used to examine the effect of temperature on the behavior of the spin label in the oxidized and reduced forms of wild-type cytochrome c and in the oxidized form of the mutated protein. The computer simulations revealed that the CW EPR spectrum for each form of cytochrome c consists of at least two components [a fast (F) and a slow (S) component], which differ in the values of the rotational correlation times tauRparallel (longitudinal rotational correlation time) and tauRperpendicular (transverse rotational correlation time) and that the relative contributions of the F and S components of the spectra change with temperature. In addition, the values of the rotational correlation times (tauRparallel and tauRperpendicular) for the F component appear to change much more dramatically with the temperature than the respective values for the S component. A large difference between the behavior of the oxidized and reduced wild-type spin-labeled cytochromes c indicates that the temperature-induced unfolding of the protein in the region around C102 progresses more rapidly when cytochrome c is in the oxidized form.     

Peritonitis-induced antitumor activity of peritoneal macrophages from uremic patients

The macrophages belong to the effector cells of both nonspecific and specific immune response. These cells generally express little cytotoxicity unless activated. The present work was intended to determine if peritoneal macrophages collected from patients on Continuous Ambulatory Peritoneal Dialysis (CAPD) during episodes of peritonitis were active against human tumor cell lines without further in vitro stimulation. We also compared macrophage antitumor potential with effectiveness of drugs used in cancer therapy (taxol and suramin). Conditioned medium (CM) of macrophages collected during inflammation-free periods did not exhibit cytostatic and cytotoxic activity against both tumor (A549 and HTB44) and non-transformed (BEAS-2B and CRL2190) cells. Exposure of tumor cells to CM of macrophages harvested during peritonitis resulted in significant suppression of proliferation, impairment of viability and induction of apoptosis, in contrast to non-transformed cells, which remained unaffected. The efficacy of CM of inflammatory macrophages as an antitumor agent appeared to be comparable to cytostatic and cytotoxic potency of taxol and suramin or, in the case of HTB44 cells, even higher. The results obtained suggest that activated human macrophages might represent a useful tool for cancer immunotherapy.     

Surface interaction of human granulocytes and lymphocytes with staphylococcal extracellular serine proteinase

Enzymatic activity of purified staphylococcal extracellular serine proteinase decreases as a result of incubation with granulocytes as well as with lymphocytes taken from peripheral blood of healthy donors. However, specific proteinase binding was observed only in the case of granulocytes but not in peripheral lymphocytes.     

The comparison of lysosomal enzymes activities in alveolar and peritoneal macrophages of rat

Studies were carried out on macrophages isolated from control and thioglycollate injected rats. Intraperitoneal injection of thioglycollate had no effect on the number of harvested alveolar macrophages but caused a marked increase in the number of peritoneal macrophages. The specific activities of all the investigated enzymes were significantly lower in peritoneal macrophages from control rats in comparison to alveolar macrophages. Thioglycollate stimulation of peritoneal macrophages caused increase in activities of all lysosomal hydrolases studied. Cathepsin B, N-acetylglucosaminidase and esterase showed the highest level of stimulation.