Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The debate over the potential risk of tumorigenicity attributable to the use of CCL substrates for biologicals production has continued for over 30 years and may continue for some time to come. Manufacturers and regulatory agencies are developing scientifically based guidelines for such products. It is currently possible to follow these guidelines to prepare recombinant biologicals and monoclonal antibodies in CCLs which do not pose unreasonable risks. This chapter has attempted to describe the scientific tools available to evaluate the putative risk of tumorigenicity due to potential virus DNA and protein contaminants. No theoretical or experimental basis exists to hypothesize that residual cellular protein might present a significant risk of tumorigenicity. The tools are certainly adequate for characterization of putative risks due to viruses and DNA but are not sufficiently powerful by themselves to assure product safety. The subsequent chapter on process validation describes how adequate assurances of safety ultimately can be obtained for products of CCLs against theoretical risks of tumorigenicity due to putative viruses and DNA. In addition to these safeguards, no evidence of tumorigenicity has been found in human or livestock animal recipients of the products prepared in CCL substrates. Many patients have received inoculations of tissue plasminogen activator, erythropoeitin, factor VIII, soluble CD4, GM-CSF, hepatitis B surface antigen vaccine, and various monoclonal antibodies and other recombinant products of continuous cell lines in clinical trials. For tissue plasminogen activator, large doses of 100 mg per patient or more have been used. At the time of writing over 10 kg of CHO-derived tissue plasminogen activator has been sold since late 1987 for administration to over 100,000 human patients. For recombinant factor VIII, erythropoeitin, and soluble CD4 proteins, chronic administration has been employed. Millions have received polio and rabies vaccines prepared in continuous Vero cells. In addition to this human experience, livestock animals have received annual inoculations of foot-and-mouth virus vaccine prepared in BHK-21 (a highly tumorigenic CCL) for up to 14 years without effect (69). No effects have been reported which might be attributed to oncogenic factors. Thus, scientific tools of characterization and principles of process validation are available to protect patients from putative risks of tumorigenicity associated with products prepared in CCLs. Increasing clinical experience also supports this conclusion.
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PMID:Continuous cell substrate considerations. 137 28

The mRNAs of transiently expressed cytokine genes contain AUUUA-rich sequences in the 3' untranslated regions. In order to examine whether the AU-specific endoribonuclease V (EC 3.1.27.8) described previously by us transinactivates those mRNA species, we introduced a 51-nucleotide ATTTA sequence from tumor necrosis factor into the 3' untranslated region of beta-globin gene. Transcripts of that construct, synthesized in vitro, were prone to endoribonuclease V digestion at those AU-rich sequences. Stimulation of human macrophages with lipopolysaccharide resulted in a shift of the association state of the enzyme from the nuclear matrix-associated to the free form. This shift was strongly prevented by the hepatitis B surface antigen (HBsAg) and more weakly by hepatitis B nucleocapsid antigen and hepatitis B antigen of the X region. HBsAg and, to a lesser extent, hepatitis B nucleocapsid antigen and hepatitis B antigen of the X region inhibited the release of alpha interferon, tumor necrosis factor alpha, and granulocyte-macrophage colony stimulating factor, while it had no effect on interleukin-1 production from stimulated macrophages. Using the human hepatoma cell line PLC/PRF/5, we provide further experimental evidence that endoribonuclease V acts in trans as a posttranscriptional inactivator for nuclear matrix-associated cytokine transcripts. These results suggest that those cytokine transcripts which contain reiterated (overlapping) AUUUA sequences are degraded by nuclear matrix-associated endoribonuclease V. This degradation was comparably high in cells incubated with HBsAg or cells which produced this antigen.
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PMID:Immunosuppressive function of hepatitis B antigens in vitro: role of endoribonuclease V as one potential trans inactivator for cytokines in macrophages and human hepatoma cells. 215 63

The uses of GM-CSF as an immunomodulator and vaccine adjuvant are reviewed. GM-CSF has a variety of effects on immune responses: it induces class II major histocompatibility complex antigen expression on the surface of macrophages; it enhances dendritic cell maturation and migration; it results in a localized inflammation at the injection site; and it has marked effects on maturation of haematopoietic progenitor cells in the bone marrow. Animal and human studies suggest that administration of GM-CSF can increase antibody titres to foreign antigens. Monkeys injected with human interleukin (IL)-3 plus GM-CSF, at a different injection site, developed peak antibody titres which were 8- to 30-fold higher than those in monkeys injected with IL-3 alone. In a study of ovarian cancer patients receiving GM-CSF to prevent chemotherapy-induced neutropenia, two patients who had demonstrated a low titre of antithyroid antibodies prior to the study showed an increase in antibody titre and transient thyroiditis after administration of GM-CSF. Recently a GM-CSF/antigen fusion protein has been tested. An antibody corresponding to a specific idiotype expressed on B-cell lymphomas was fused to GM-CSF and injected into mice with B-cell lymphoma xenografts. The mice developed antibodies to the lymphoma and there was a protective effect against disease progression. Preliminary results of clinical trials using GM-CSF in humans suggest that it enhances antibody responses to hepatitis B vaccine. On the basis of these preliminary results, several clinical trials are being planned and it would appear that GM-CSF has potential as a vaccine adjuvant.
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PMID:Potential role of granulocyte-macrophage colony-stimulating factor as vaccine adjuvant. 787 53

Gene/biotechnology products can be either physiological peptides for the purpose of substitution of deficiencies or for therapeutic purposes in superphysiological concentrations, or nonphysiological peptides, or newer biotechnology products like monoclonal antibodies. The rules for clinical trials developed so far are also valid for clinical trials with gene/biotechnology products. Nevertheless, a major challenge for the clinical pharmacologist is the species specificity of many reactions induced by gene/biotechnology products in man. In general, animal experiments may be less predictive, so there is a greater demand for human pharmacology studies. Gene/biotechnology products offer more chances for treatment of many diseases, but during the clinical trials the clinician has to always be aware of unexpected side effects. Several newer gene technology products offer superior safety as compared to older biological products like Factor VIII preparations and human growth hormone. More than 19 therapeutics produced by gene/biotechnology have already been approved by health authorities all over the world. Major clinical benefit could be shown with hepatitis B vaccine, insulin, human growth hormone, TPA, erythropoietin, GM-CSF, G-CSF, and monoclonal antibodies for immune suppression. There is also good evidence of efficacy of interferon alpha in chronic hepatitis. So far, our knowledge about cytokines is still limited. In several cancer diseases, interferons show efficacy as well as in several autoimmune diseases. Well designed clinical pharmacology studies will be important to elaborate the therapeutic potential of drugs arising from gene/biotechnology.
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PMID:Clinical trials of gene/biotechnology products. 788 81

Ten patients with chronic hepatitis B received increasing doses of nIL-2 (30,000 U, 100,000 U, 300,000 U, 1.0 million U) subcutaneously in a phase I trial. Each dose was applied once per week over 3 weeks. Serum samples were taken before and 2, 12, 24, 48 and 72 h after the first application of each dose level. Serum concentrations of interleukin-1 (IL-1), IL-2, IL-6, interferon-alfa (IFN-alpha), IFN-gamma, tumor necrosis factor-alpha (TNF-alpha) and GM-CSF as well as the cytokine-dependent serum components neopterin, beta-2-microglobulin (B2M), C-reactive protein (CPR), soluble IL-2-receptor (sIL-2R) and 2'-5'-oligoadenylate synthetase (2-5 OA) were assayed using ELISAs and RIAs. None of the samples tested contained measurable cytokine levels other than IL-2. A low and non-toxic dose of 300,000 U nIL-2 was already biologically active with induction of neopterin, B2M and sIL-2R. Dose-dependent changes peaked 24-48 h after application. The same patients were then enrolled in a phase II trial. Treatment in five of the patients was continued twice per week for 3 months with a biologically active dose of 300,000 U nIL-2 subcutaneously. Two of these patients as well as another five patients from the original group were treated with 1.0 million U nIL-2 subcutaneously, twice weekly for 3 months. Neither a biologically active but non-toxic dose of 300,000 U nIL-2, nor a toxic dose of 1.0 million U resulted in permanent clearance of hepatitis B early antigen (HBeAg).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pilot study of natural human interleukin-2 in patients with chronic hepatitis B. Immunomodulatory and antiviral effects. 830 Oct 59

Recombinant human granulocyte-macrophage colony-stimulating factor is being used to improve the immunological function of patients with various diseases and to ameliorate hematological disorders. We investigated the tolerance and possible antiviral effect of the administration of daily doses of recombinant human granulocyte-macrophage colony-stimulating factor (3, 1 or 0.5 micrograms/kg body wt) to nine patients with chronic hepatitis B, alone or in combination with 5 MU interferon-alpha 2b. Recombinant human GM-CSF reduced significantly (p < 0.02) hepatitis B virus DNA levels. The three doses used were equally effective. Of the eight patients who completed the study, four became negative for HBV DNA and HBeAg; two of them seroconverted to HBe antibody. These four patients showed improvement in the histological activity of their liver disease. Ultimately, two patients regained normal ALT values. 2',5'-Oligoadenylate synthetase activity increased significantly (p < 0.01) in cell lysates of mononuclear cells cultured in vitro, coinciding with the reductions in hepatitis B virus DNA levels. Recombinant human granulocyte-macrophage colony-stimulating factor was well tolerated but produced a dose-dependent increase in white blood cell counts. It became intolerable at doses of 3 micrograms (and was reduced to 1.5 microgram); this effect was reversible after cessation of recombinant human granulocyte-macrophage colony-stimulating factor treatment. No remarkable variations occurred in other parameters. In conclusion, recombinant human granulocyte-macrophage colony-stimulating factor administration is safe and tolerable at doses of 0.5 to 1 microgram/kg body wt and may exert an antiviral effect in chronic hepatitis B.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pilot study of recombinant human granulocyte-macrophage colony-stimulating factor in the treatment of chronic hepatitis B. 840 50

Recent advances in basic science and clinical trials have demonstrated that IFNs and myeloid hematopoietins play crucial roles in host defense against pathogens and immune surveillance. Here we have reviewed the biologic functions of GM-CSF, G-CSF, IFN-alpha and IFN-gamma. For patients with neutropenia resulting from cytotoxic chemotherapy, bone marrow transplantation, congenital agranulocytosis and cyclic neutropenia, therapeutic uses of GM-CSF and G-CSF were reviewed. Application of these growth factors to patient management represents a major contribution of biotechnology to a difficult area of therapeutics in febrile, neutropenic patients. Because IFN-alpha plays crucial roles in antiviral responses, its clinical applications in hepatitis B and C, human papilloma virus, HIV infection and malignancy were discussed. The use of IFN-gamma in bacterial prophylaxis in patients with chronic granulomatous disease was also presented. Advances in clinical applications of IFNs and hematopoietic growth factors serve as a paradigm for further development to investigate the use of other important cytokines in modern therapeutics.
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PMID:Biology and therapeutic uses of myeloid hematopoietic growth factors and interferons. 904 17

Recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) has been shown to augment antigen presentation by macrophages and dendritic cells in vitro, and to increase antibody responses to injected antigens in experimental animals. To evaluate the usefulness of rhGM-CSF as a vaccine adjuvant, 108 healthy volunteers were randomly assigned to receive an injection of rhGM-CSF (n = 81) or placebo (control group; n = 27), followed by an injection with recombinant hepatitis B vaccine into the same site. During the study period of 28 days, protective antibody titers to hepatitis surface antigen (anti-HBs10 mIU ml-1) were observed in 11 of 81 subjects receiving rhGM-CSF, but in none of the controls (P = 0.035). Injections were well tolerated. A single i.m. or s.c. injection of 20-40 micrograms of rhGM-CSF significantly enhances antibody responses when given at the same site as recombinant hepatitis B vaccination.
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PMID:Evaluation of tolerability and antibody response after recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) and a single dose of recombinant hepatitis B vaccine. 896 5

An open label trial of GM-CSF plus high-dose interferon (IFN) alpha 2b was performed in eight patients with chronic hepatitis B infection and 16 patients with chronic hepatitis C, who either failed to clear virus with 6 months of daily high-dose IFN (5 MU daily) therapy (n = 22) or were considered untreatable because of advanced disease and leukopenia (n = 2). The dose of GM-CSF used was 500 micrograms subcutaneously twice weekly. The dose of IFN used was 5 MU daily. Both agents were administered for 4 months. Five of the eight hepatitis B patients and five of the 16 hepatitis C virus patients responded to combined therapy having previously failed IFN therapy alone. The hepatitis B virus responders had low entry ALT, AST, and gamma GPT levels as compared to the non-responders. No such differences for responders and non-responders were seen with the hepatitis C virus patients. These data suggest that the combination of GM-CSF and IFN may be more effective at achieving viral clearance than IFN alone.
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PMID:A preliminary experience with GM-CSF plus interferon in patients with HBV and HCV resistant to interferon therapy. 909 87

Genetic immunization is a potentially useful strategy to prevent or treat hepatitis B virus (HBV) infection. We have previously shown that HBV envelope proteins are highly immunogenic using this technique. The large envelope protein (LHBs), however, induced significantly weaker humoral and cellular immune responses when compared with the middle envelope protein (MHBs). We studied the effect of co-immunizations with cytokine DNA expression constructs encoding for interleukin (IL)-2 and (GM-CSF) on the immunogenicity of LHBs at the B-and T-cell level. Co-immunizations of mice with plasmids encoding for MHBs and IL-2 or GM-CSF increased anti-HBs responses, helper T-cell proliferative activity, and cytotoxic T lymphocyte (CTL) killing. In contrast, co-immunizations of plasmids encoding for LHBs and IL-2 or GM-CSF had no effect on humoral and cellular immune responses. LHBs did not inhibit the production or secretion of IL-2 and GM-CSF. In addition, IL-2, tumor necrosis factor alfa (TNF-alpha), and interferon gamma (IFN-gamma) had no suppressive effect on HBV envelope protein expression in vitro. Based on these data, MHBs, but not LHBs, genetic immunization can be augmented by IL-2 or GM-CSF cytokines.
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PMID:Cytokine and hepatitis B virus DNA co-immunizations enhance cellular and humoral immune responses to the middle but not to the large hepatitis B virus surface antigen in mice. 965 13


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