Search PubMed⌕ Search

Biomedical subjects

H Rollag

Publications and source records attributed to H Rollag.

At least 73 records · Page 4Linked to original sources
PubMed1988

Interferons affect oxygen metabolism in human neutrophil granulocytes.

Human polymorphonuclear neutrophil granulocytes (PMN) were incubated with recombinant interferons (IFNs) and tested for O2 consumption, hydrogen peroxide formation, and chemiluminescence. N-formyl-methionyl-leucyl-phenylalanine (f-MLP, a bacterial peptide analogue) and phorbol myristate acetate (PMA, a protein kinase C activator) were used as PMN stimuli. An increase in O2 consumption after f-MLP-stimulation was seen when PMN had been incubated 2-4 h with either 1000 IU/ml IFN-alpha or 100 IU/ml IFN-gamma, but this increase in O2 consumption was not observed with 1000 IU/ml IFN-beta. Likewise, 100 U/ml IFN-gamma enhanced f-MLP stimulated chemiluminescence, whereas IFN-alpha or IFN-beta (1000 U/ml) had no detectable effects. None of the interferons affected baseline or PMA-stimulated O2 consumption and chemiluminescence, nor did they influence the H2O2-dependent oxidation of intracellular dichlorofluorescein (DCFH) (baseline, f-MLP-stimulated or PMA-stimulated). Our data indicate that some--but not all--aspects of oxygen metabolism in PMN can be affected by IFN, and that there are differences between various subtypes of IFNs regarding their neutrophil priming potential.

Granulocytes↗
PubMed1988

The effect of recombinant interferons on cathepsin B activity in human monocytes.

Blood monocytes isolated from healthy human donors were cultivated for 3 days in the presence of recombinant human interferons (rHuIFN) alpha, beta, gamma. Intracellular activity of cathepsin B was recorded. All rHuIFNs suppressed the cathepsin B activity in the monocytes, rHuIFNs alpha and beta suppressed in a dose-dependent manner, whereas rHuIFN-gamma was suppressive only at low concentrations (1-10 U/ml). In parallel experiments, monocytes were stimulated with carrageenan, which caused increased cathepsin B activity in the cells. This increase was reduced to the level of activity in nonstimulated cells by all rHuIFNs. We have previously reported that cathepsin B may be involved in the pathogenesis of rheumatoid arthritis, and the present results may have a bearing on the effects of HuIFNs on the immune system.

Carrageenan↗
PubMed1988

Rapid diagnosis of genital herpes simplex infection by an indirect ELISA method.

Herpes simplex virus (HSV) detection was performed by a rapid ELISA antigen detection method in a small field trial, and the results were compared to the results of ordinary cell culture isolation. Swabs from 54 patients, suffering from clinically suspected genital HSV infection, were examined by both methods. In 49 samples the results were identical. Three samples were negative by ELISA, but HSV was isolated by culture, while two samples were positive by ELISA, but negative by culture. Compared to the culture results, the ELISA method had 87.5% sensitivity and 93.3% specificity. Most culture positive samples were identified within two (54%) or three (75%) days, and all within six days after inoculation. The ELISA method turned out as a good and easy method for rapid detection of genital HSV infections.

Enzyme-Linked Immunosorbent Assay↗
PubMed1987

HIV infection in Norwegian haemophiliacs: the prevalence of antibodies against HIV in haemophiliacs treated with lyophilized cryoprecipitate from volunteer donors.

334 of 389 (86%) registered Norwegians with coagulation factor defects were screened for antibodies to the human immunodeficiency virus (HIV) in 1985/1986. 21 persons were confirmed anti-HIV positive. They were all persons with clinically severe haemophilia A and represent 18.4% of 114 tested persons with severe haemophilia A. 3 patients have developed AIDS, 3 have persistent generalized lymphadenopathy. At least 8 of the 21 seropositive persons (38%) have been infected through lyophilized cryoprecipitates prepared from volunteer plasma donated in national blood banks. None of 10 heterosexual partners have antibodies to HIV. We conclude that the policy of using small-pooled lyophilized cryoprecipitates instead of commercial concentrates has reduced HIV-infection among Norwegian haemophiliacs. Today, the prevalence of HIV antibodies in the haemophilia population in Norway is among the lowest in Western Europe.

Acquired Immunodeficiency Syndrome↗
PubMed1987

The significance of HIV antigen and HIV antibodies specific against envelope and core proteins in serum of HIV-infected hemophiliacs.

Serial serum samples from the 21 HIV-infected Norwegian hemophiliacs have been assayed for the presence of HIV antigen and antibodies to HIV specific for the core protein p24 and the envelope protein gp41. HIV antigen was detected in 4 patients, of whom 3 have developed AIDS to date. HIV antigen appeared in serum 10 to 24 months before the diagnosis in these patients. Antibodies to gp41 was a constant finding. Antibodies to p24 disappeared from the serum in 1 patient who developed AIDS and from 3 persons free of symptoms related to the HIV infection. The detection of HIV antigen in HIV antibody-positive hemophiliacs appears to be of considerable prognostic significance.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Effect of fibroblast interferon and recombinant gamma interferon on zymosan-induced nitroblue tetrazolium reduction in mouse peritoneal macrophages.

Mouse peritoneal macrophages (MPM) were cultivated with a fibroblast interferon (IFN) preparation or recombinant gamma-IFN (rIFN-alpha) for 1, 24 or 48 h. The zymosan-induced reduction of nitroblue tetrazolium (NBT) in these MPM was then measured. Fibroblast IFN enhanced the NBT reducing capacity of MPM when the incubation period was 1 h. When the incubation period was extended to 48 h, a suppressed NBT reduction by fibroblast IFN treated MPM was recorded. The influence of rIFN-alpha on MPM with regard to NBT reduction was minor. Only when the MPM were treated with a moderate dose of rIFN-alpha (10 U/ml) for 48 h was an enhanced NBT reduction recorded.

Animals↗
PubMed1985

Antibody to hepatitis B surface antigen among employees in the National Hospital, Oslo, Norway: a prevalence study.

During the last decade, several studies of serologic markers of hepatitis B virus infections in hospital personnel have demonstrated an increased prevalence of antibodies to hepatitis B virus (anti-HB) compared with the general population. Norway has a very low incidence rate of hepatitis B as seen on a global scale, and this study was performed to evaluate the infection risk by hospital workers in such environments. The employees, 2,546 (94.7% of the population), in the 800-bed National Hospital in Oslo were tested for antibody to hepatitis B surface antigen (anti-HBs) in serum. Five per cent (128 persons) were anti-HBs-positive; this was only slightly higher than that in the general Norwegian population. Male employees were more often positive than females (7.0% vs. 4.4%). Staff more than 50 years of age or with 16 or more years of employment in the health services had a rate twice as high as the rest of the employees. Staff in the porter services (mostly men) had a higher rate than others, whereas the rates in the different professional groups showed no statistical differences. Contrary to many other studies, significant differences in prevalence according to frequency of patient contact or blood handling were not found.

Adolescent↗
PubMed1985

Effect of gamma interferon on spreading of mouse peritoneal macrophages on solid surfaces.

The influence of a homologous gamma interferon preparation (MuIFN-gamma) on in vitro spreading of freshly-seeded unelicited mouse peritoneal macrophages (MPM) was tested. Light microscopy and scanning electron microscopy observations gave comparable results. Addition of MuIFN-gamma enhanced the spreading on solid surfaces, especially 3-5 hours after seeding. Maximal effect was achieved with 10 units of IFN. Addition of specific anti-MuIFN-gamma or treatment of the preparation at pH 2 eliminated both antiviral activity and effect on spreading of MPM.

Animals↗
PubMed1984

Effects of interferon-alpha/beta and interferon-gamma preparations on phagocytosis by mouse peritoneal macrophages.

The influence of murine alpha/beta-interferon (Mu IFN-alpha/beta) and murine gamma-interferon (Mu IFN-gamma) preparations on the attachment and ingestion phase of phagocytosis by mouse peritoneal macrophages (MPM) was studied. A non-opsonized strain of Escherichia coli, IgG-opsonized E. coli, and sheep erythrocytes opsonized with IgG (E-IgG) and IgM plus complement factor C3b (E-IgMC) were used as test particles. Pretreatment of MPM with 10(2)-10(3) U/ml of Mu IFN-alpha/beta for 24 h enhanced both attachment and ingestion of bacteria or erythrocytes mediated by the non-specific receptor, the Fc receptor, or the C3b receptor. Higher concentrations had no such effects. In contrast, treatment of MPM with 10(1)-10(2)U/ml of Mu IFN-gamma suppressed attachment and ingestion of non-opsonized and IgG-opsonized E. coli and of E-IgG by 10-40%. Mu IFN-gamma did not influence attachment and ingestion of E-IgMC. The effects were neutralized by specific anti-IFN antiserum. The data indicate that the IFN effect on phagocytic activity is, at least to a large extent, due to modifications of the surface receptors.

Animals↗
PubMed1984

Phagocytosis of non-opsonized Escherichia coli by mouse peritoneal macrophages. An electron microscopic study.

Phagocytosis of non-opsonized Escherichia coli by mouse peritoneal macrophages (MPM) was studied by means of light microscopy, scanning electron microscopy and transmission electron microscopy. During a phagocytosis period of 90 min the surface morphology changed. Early in the phagocytosis period the MPM were polar with many ridges and villi, and little ruffling. At the end of the period the cells appeared well spread with a smooth surface and extensive ruffling. Two modes for ingestion of bacteria seemed to exist. The bacteria were ingested either by membrane folds rising from the macrophage surface, fitting tightly to the bacteria or by bacteria sinking into the cytoplasm of the MPM. Early in the period of phagocytosis most bacteria were attached to the surface. Ten per cent of the bacteria attached were never ingested. Bacteria ingested were located in phagolysosomes that were either of a tight or a loose type. After a phagocytosis period of 90 min the phagolysosomes contained bacteria at different stages of degradation. During the degradation the bacteria showed several morphological changes including a decrease in the density of the endoplasm, detachment of the bacterial membrane from the cell wall and deformities in the bacterial cell wall.

Animals↗
PubMed1983

Influence of the genotype of mice on the effect of interferon on phagocytic activity of macrophages.

The influence of genotype on interferon effect on phagocytic activity of unstimulated mouse peritoneal macrophages (MPM) was studied in in vitro experiments. Treatment of MPM from BALB/c and ICR mice with mouse fibroblast interferon (MuIFN-beta) enhanced the ingestion of non-opsonized Escherichia coli. This effect was dose-dependent and neutralized by anti-interferon globulin. MPM from C57B1/6 mice were not stimulated by the same treatment. Treatment of MPM with pH 2-sensitive immune interferon (MuIFN-gamma) depressed the ingestion independently on the genotype of mice.

Animals↗
PubMed1982

Effect of murine beta-interferon preparation on phagocytosis and cyclic AMP levels in mouse peritoneal macrophages.

Mouse peritoneal macrophages (MPM) cultivated with a mouse beta-interferon preparation (MuIFN-beta) or "mock" IFN were tested for phagocytic ability and intracellular levels of adenosine 3',5'-cyclic monophosphate (cAMP). Suspensions of nonopsonized Escherichia coli (E. coli) were used for phagocytosis experiments. Treatment of MPM with 10(1)-10(3) U per ml of MuIFN-beta stimulated the phagocytic activity and raised the levels of cAMP in MPM. The effect of MuIFN-beta on cAMP levels were dose and time dependent. Maximal cAMP levels were seen when MPM were incubated with 10(3)-10(4) U per ml of MuIFN-beta for five hours. Simultaneous addition of MuIFN-beta and the adenylcyclase inhibitor N-ethylmaleimide to the MPM cultures prevented the rise in cAMP levels but not the increased phagocytic capacity. MuIFN-beta induced enhancement of phagocytosis and elevation of cAMP levels in MPM seem to be two parallel but not interlinked processes.

Animals↗
PubMed1982

Effect of a homologous beta-interferon preparation on degradation of Escherichia coli and on lysosomal enzyme activities in mouse peritoneal macrophages.

The degradation of 32P-labelled E. coli and the activity of three lysosomal enzymes, acid phosphatase, cathepsin D and beta-glucuronidase, in mouse peritoneal macrophages (MPM) were tested after cultivation of the cells for 24 or 48 hours with 10(1) - 10(4.7) U per ml of a homologous beta-interferon preparation (IFN-beta). Low to moderate concentrations of IFN-beta did not influence bacterial degradation in MPM. However, a reduction in bacterial degradation by 20 per cent or more was seen when the MPM were pre-treated with 10(4.7) U per ml for 24 hours or 10(3) U per ml of IFN-beta for 48 hours. Cultivation of the MPM with 10(2) U per ml of IFN-beta suppressed the activities of the lysosomal enzymes, provided that the cells were treated for 48 hours. The beta--glucuronidase activity was significantly reduced also after 24 hours. Increased release of beta-glucuronidase from MPM to the medium during cultivation with 10(2) U per ml of IFN-beta was also observed. Specific anti-IFN-beta globulin abolished the suppression by IFN-beta on the lysosomal enzyme activities. A human IFN-alpha preparation did not influence bacterial degradation or lysosomal enzyme activities in MPM.

Acid Phosphatase↗
PubMed1982

Effect of beta-interferon on in vitro spreading of mouse peritoneal macrophages.

The influence of a homologous beta-interferon preparation (MuIFN-beta) on in vitro adherence and the early and late phase of spreading of mouse peritoneal macrophages (MPM) was tested. MPM from mice pre-treated with 2 x 10(4) U of MuIFN-beta did not differ in ability to adhere to a glass surface, compared to controls. However, when the early phase of MPM spreading was tested, the percentage of spreading cells from mice injected with MuIFN-beta or Newcastle disease virus was almost doubled as compared to MPM from control mice. To assay the late phase of MPM spreading, MPM from unstimulated mice were seeded on glass surfaces and cultivated with or without MuIFN-beta for 1-24 hours. MuIFN-beta enhanced the spreading of MPM with maximal difference 3-5 hours after seeding. The effect was dose-dependent up to 10(2)U per ml of MuIFN-beta. The effect was also species--specific and neutralized by addition of anti-MuIFN-beta globulin. Morphometric measurements of the spreading of MPM indicated that after 24 hours of MuIFN-beta treatment the mean area occupied was 50 per cent larger than that of controls.

Animals↗
PubMed1981

Effect of gamma interferon preparations on in vitro phagocytosis and degradation of Escherichia coli by mouse peritoneal macrophages.

Treatment of mouse peritoneal macrophages by gamma (type II, immune) interferon depressed the ingestion of non-opsonized Escherichia coli mediated by the non specific receptor, and also the intracellular degradation of the ingested bacteria. These effects were time and dose-dependent, and sensitive for trypsin and pH 2 treatment. The intracellular concentration of three lysozomal enzymes, beta-glucuronidase, acid phosphatase and cathepsin D, was elevated in gamma interferon-treated macrophages.

Acid Phosphatase↗