Cloning,expression, and antiviral activity of interferon β from the Chinese microbat,Myotis davidii

Bats are natural reservoir hosts for many viruses that produce no clinical symptoms in bats.Therefore, bats may have evolved effective mechanisms to control viral replication. However, little information is available on bat immune responses to viral infection. Type I interferon(IFN) plays a key role in controlling viral infections. In this study, we report the cloning, expression, and biological activity of interferon β(IFNβ) from the Chinese microbat species, Myotis davidii. We demonstrated the upregulation of IFNB and IFN-stimulated genes in a kidney cell line derived from M. davidii after treatment with poly I:C or infection with Sendai virus. Furthermore, the recombinant IFNβ inhibited vesicular stomatitis virus and bat adenovirus replication in cell lines from two bat species, M. davidii and Rhinolophus sinicus. We provide the first in vitro evidence of IFNβ antiviral activity in microbats, which has important implications for virus interactions with these hosts.     

Neutralizing interferon β antibodies in melanoma patients treated with recombinant and natural interferon β

The incidence and clinical significance of therapy-induced neutralizing interferon (IFNß) antibodies was studied in a group of 21 melanoma patients treated with natural IFNß and 7 patients treated with recombinant IFNß. They were treated subcutaneously with 3×10⁶ IU three times per week in an adjuvant open trial for 24 weeks after surgical removal of all detectable metastases. Of the 21 patients treated with natural IFNß, 95% developed significant levels of neutralizing antibodies after 24 weeks. In comparison, 28% of the 7 patients treated with recombinant IFNß developed neutralizing IFNß antibodies. Cross-reactivity of the antibodies could be demonstrated. Persistence of antibody titers was seen in 80% of the patients 24 weeks after cessation of treatment with natural IFNß. No correlation between the maximum antibody titers and the antibody persistence after cessation of therapy could be established. We detected a clear correlation between the formation of neutralizing antibodies and the decrease in 2-microglobulin and 2,5-oligoadenylate synthease and therefore the drop in biological activity. In this adjuvant trial there was no difference in relapse rate and time until relapse between antibody-positive and antibody-negative patients. No difference in clinical outcome could be established between the patients treated with natural IFNß and recombinant IFNß.     

Antitumor effect of combination of murine recombinant interferon β, murine recombinant interferon γ and human recombinant interleukin-2 in MethA-bearing mice

Summary We have previously reported that the combination of murine recombinant interferon (Mu-rIFN) with murine recombinant interferon (Mu-rIFN) provided greater inhibition of tumor growth than did each one alone in MethA-bearing mice. In the present study the effect of addition of human recombinant interleukin-2 (Hu-rIL-2) to the combination of Mu-rIFN with Mu-rIFN on tumor growth in BALB/c mice bearing syngeneic MethA fibrosarcoma was examined. Low doses of Hu-rIL-2 (5 × 10³ U or 5 × 10⁴ U at 3-day intervals) showed no antitumor activity, while a high dose of Hu-rIL-2 (5 × 10⁵ U) showed profound growth inhibition. The administration of IL-2 (ranging between 5 × 10³ U and 5 × 10⁵ U) in addition to the combination of IFN and IFN showed more augmented antitumor effects in a dose-dependent manner. Furthermore, the simultaneous administration of IL-2, IFN and IFN had more effective therapeutic activity, compared with the sequential administration of interferons and IL-2. These findings indicated that IL-2 in combination with IFN and was effective for cancer treatment.     

Syntenic mapping and chromosomal localization of bovine α and β interferon genes

The previous assignment of bovine -(IFNA) and -(IFNB) interferon gene families to syntenic group U18 was confirmed with additional cDNA probes and a bovine-rodent hybrid somatic cell panel representing all 29 bovine autosomal syntenic groups. Fluorescent in situ hybridization (FISH) localized these genes to bovine Chromosome (Chr) 8 band 15 and demonstrates that with biotinylated plasmids, as few as five tandemly arrayed sequences can be detected by conventional fluorescent microscopy. This technique can be applied to physical mapping of other multicopy genes in domestic animals.     

Sensitivity of ortho- and paramyxovirus replication to human interferon α

Replication of the influenza virus strains Influenza Ao/WSN (H0N1), fowl plague (Hav1N1) and B-Lee/40 (ATCC) and the paramyxovirus, New Castle disease virus (Victoria) are highly sensitive to human interfereon type in Madin Darby bovine kidney cells. Pretreatment of cells with human interferon type resulted in protection of the cells against viral cytopathic effect. The inhibition of the orthomyxovirus strains used in this study and New Castle disease virus replication is mediated by an inhibition of viral protein synthesis. Residual WSN virus particles released from interferon treated cells showed the same structural protein pattern as virus particles isolated from control cells. Glycosylation of the viral structural components appeared to be unaffected by interferon.     

Inhibitor of IκB kinase activity,BAY 11-7082, interferes with interferon regulatory factor 7 nuclear translocation and type I interferon production by plasmacytoid dendritic cells

Introduction

Plasmacytoid dendritic cells (pDCs) play not only a central role in the antiviral immune response in innate host defense, but also a pathogenic role in the development of the autoimmune process by their ability to produce robust amounts of type I interferons (IFNs), through sensing nucleic acids by toll-like receptor (TLR) 7 and 9. Thus, control of dysregulated pDC activation and type I IFN production provide an alternative treatment strategy for autoimmune diseases in which type I IFNs are elevated, such as systemic lupus erythematosus (SLE). Here we focused on IκB kinase inhibitor BAY 11-7082 (BAY11) and investigated its immunomodulatory effects in targeting the IFN response on pDCs.

Methods

We isolated human blood pDCs by flow cytometry and examined the function of BAY11 on pDCs in response to TLR ligands, with regards to pDC activation, such as IFN-α production and nuclear translocation of interferon regulatory factor 7 (IRF7) in vitro. Additionally, we cultured healthy peripheral blood mononuclear cells (PBMCs) with serum from SLE patients in the presence or absence of BAY11, and then examined the inhibitory function of BAY11 on SLE serum-induced IFN-α production. We also examined its inhibitory effect in vivo using mice pretreated with BAY11 intraperitonealy, followed by intravenous injection of TLR7 ligand poly U.

Results

Here we identified that BAY11 has the ability to inhibit nuclear translocation of IRF7 and IFN-α production in human pDCs. BAY11, although showing the ability to also interfere with tumor necrosis factor (TNF)-α production, more strongly inhibited IFN-α production than TNF-α production by pDCs, in response to TLR ligands. We also found that BAY11 inhibited both in vitro IFN-α production by human PBMCs induced by the SLE serum and the in vivo serum IFN-α level induced by injecting mice with poly U.

Conclusions

These findings suggest that BAY11 has the therapeutic potential to attenuate the IFN environment by regulating pDC function and provide a novel foundation for the development of an effective immunotherapeutic strategy against autoimmune disorders such as SLE.     

Humoral and cellular responses of colorectal cancer patients treated with monoclonal antibodies and interferon γ

Summary Fifteen patients with metastatic gastrointestinal adenocarcinomas were treated with low doses of recombinant human interferon (rh-IFN) and a mixture of monoclonal antibodies (mAb) that bind to tumor cells. All antibodies were of the IgG2a isotype and interact with human effector cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC). Natural killer lysis against K562 cells by peripheral blood mononuclear cells purified from patients' blood was enhanced in all patients at day 3 during IFN treatment. Monocytes from two patients had increased ADCC levels. Increase in the percentage of monocytes able to bind mouse IgG2a was detected by Fc receptor flow cytometry analysis 24 h after the first IFN infusion. However, 3 days later, the percentage of fluorescent cells had fallen below baseline levels. The analysis of patients' sera showed that at day 2 after mAb infusion, only 50% of the circulating mouse IgG was immunoreactive, and after 1 week, only traces of immunoreactive mouse IgG were detected. All patients developed a human anti-(mouse Ig) response of IgG, IgM and IgA isotypes, although only low levels of anti-idiotypic antibodies were detected at the time of testing (up to 9 weeks) after mAb infusion. No difference in the IgG subclasses of anti-(mouse Ig) antibody was observed between patients treated with mAb and IFN and patients treated with mAb alone.This work was supported by a fellowship from the Minister of Foreign Affairs, France, and National Institutes of Health Grants CA10815, CA25874 and CA21124.     

Comparison of retroviral p15E-related factors and interferon α in head and neck cancer

Head and neck squamous cell carcinomas (HNscc) produce low-molecular-mass factors (low-M _r factors,M _r25,000), which are antigenically related to the immunosuppressive retroviral transmembrane envelope protein p15E. These P15E-related tumour factors are thought to be responsible for some immunological impairments found in these patients (particularly the defective monocyte chemotaxis). A sequential and functional homology has been reported to exist between a bioactive fragment of interferon (IFN) and the putative immunosuppressive region of retroviral p15E (CKS-17). In this study we investigated (a) a possible functional and structural relationship between p15E and IFN, and (b) the presence of and the relationship between p15E-related low-M _r factors and IFN in HNscc patients. We report the following results. (a) Recombinant human (rhu) IFN was able to inhibit monocyte chemotaxis. (b) The anti-p15E antibodies crossreacted with rhuIFN in a dot-blot technique, however, the anti-IFN antibodies did not crossreact with disrupted murine leukaemia virus (p15E source). (c) Low-M _r factors (n=8–11) prepared from the sera of HNscc patients, which inhibit the monocyte chemotactic responsiveness, could be adsorbed by the anti-p15E antibodies as well as by the anti-IFN antibodies. However, the abilities of the factors to adsorb to the two categories of antibodies (namely, anti-p15E and anti-IFN) did not correlate. (d) Immunohistochemically we found IFN-related epitopes, in almost all HNscc specimens studied (17/18), in locations distinctive from those of p15E-related factors. The anti-IFN antibodies used in this study mainly reacted with basal epithelial cells close to the basal membrane, the prickle and granular cells of the squamous cell carcinomas. The anti-p15E antibodies mainly reacted with corneal layers, the granular and prickle cells, and did not react with basal epithelial cells. Our findings suggest that the immunosuppressive factors produced by HNscc cells are heterogeneous and p15E- and/or IFN-related.     

Biochemical and immunological responses of hairy cell leukemia patients to interferonβ

Summary Ten hairy-cell leukemia patients were treated with interferon (IFN-) at a dose rate of 2 × 10⁶ IU/m² × 5 days for 4 weeks (induction therapy) and, thereafter, at the same dose three times a week for 11 months (maintenance therapy). The effect of this treatment on serum neopterin, 2-microglobulin, (2–5)oligoadenylate [(2–5)A _n ] levels, intracellular (2–5)A _n values and human Mx protein synthesis was analysed. There were significant rises in serum neopterin and (2–5)A _n levels during both induction and maintenance, whereas 2-microglobulin levels rose only during induction. Rises in intracellular (2–5)A _n were documented mainly during induction, but they were not significantly higher than pretherapy values. IFN provoked an increase in human Mx protein synthesis over the entire induction — maintenance period, but was only significantly higher than baseline during induction. All markers proved useful for monitoring the effects of IFN dose schedules, but were not predictive of clinical outcome. Natural killer activity and IFN production, which were initially defective, followed a different trend from that of the other factors studied, in that increases were documented only late in the course of therapy when the disease was already in remission.     

Comparative injection-site pain and tolerability of subcutaneous serum-free formulation of interferonβ-1a versus subcutaneous interferonβ-1b: results of the randomized,multicenter, Phase IIIb REFORMS study

Background

In patients with relapsing–remitting multiple sclerosis (RRMS), subcutaneous (sc) interferon (IFN)β-1a and IFNβ-1b have been shown to reduce relapse rates. A formulation of IFNβ-1a has been produced without fetal bovine serum and without human serum albumin as an excipient (not currently approved for use in the US). The objectives of this study were to evaluate tolerability, injection-site redness, subject-reported satisfaction with therapy, and clinical safety and efficacy of the serum-free formulation of IFNβ-1a versus IFNβ-1b in IFNβ-treatment-naïve patients with RRMS. The objectives of the extension phase were to evaluate long-term safety and tolerability of IFNβ-1a.

Methods

This randomized, parallel-group, open-label study was conducted at 27 clinical sites in the US. Eligible patients aged 18–60 years were randomized to receive either IFNβ-1a, titrated to 44 μg sc three times weekly (tiw) (n = 65), or IFNβ-1b, titrated to 250 μg sc every other day (n = 64) over 12 weeks. Following this, all patients received IFNβ-1a 44 μg tiw for 82–112 weeks. Primary endpoint was mean change in patient-reported pain, as assessed by visual analog scale (VAS) diary pain score (from 0 mm [no pain] to 100 mm [worst possible pain]) at the injection site, from pre-injection to 30 min post-injection over the first 21 full-dose injections. Secondary assessments included proportion of patients pain-free as recorded by VAS diary and the Short-Form McGill Pain questionnaire VAS.

Results

A total of 129 patients were included in the intent-to-treat analysis. Mean (standard deviation) change in VAS diary pain score was not significantly different between groups, although numerically lower with IFNβ-1a versus IFNβ-1b from pre-injection to immediately post-injection (1.46 [2.93] vs. 4.63 [10.57] mm), 10 min post-injection (0.70 [1.89] vs. 1.89 [5.75] mm), and 30 min post-injection (0.67 [2.32] vs. 1.14 [4.94] mm). Proportion of patients pain-free at all time periods post-injection was also not significantly different between groups. Adverse events were consistent with the known safety profiles of these treatments.

Conclusions

In IFNβ-treatment-naïve patients with RRMS, both the serum-free formulation of IFNβ-1a and IFNβ-1b treatments were generally accompanied by low-level injection-site pain and were well tolerated.

Trial registration

ClinicalTrials.gov NCT00428584

     

The role of possible risk factors for acute and late renal dysfunction after high-dose interleukin-2, interferon α and lymphokine-activated killer cells

Renal dysfunction is a frequently encountered adverse event following treatment with high-dose interleukin-2 (IL-2). Information about parameters predicting the severity of IL-2-associated renal function abnormalities is limited. In this study the role of possible risk factors in the development of high-dose IL-2-associated acute and long-term renal dysfunction was investigated. A total of 72 patients, who were treated with a regimen consisting of IL-2 (18 MIU m⁻² day⁻¹ by continuous infusion), interferon α (IFNα; 5 MIU m⁻² day⁻¹, intramuscularly) and lymphokine-activated killer (LAK) lymphocytes, were analysed. Serum creatinine measurements were performed daily during treatment, weekly between courses and monthly during follow-up. Pre-and posttreatment 24-h urine samples were collected for calculation of creatinine clearances. Renal dysfunction was observed in 97% of patients. Grade 1 dysfunction (according to WHO criteria) was observed in 20 patients (28%), grade 2 in 37 (51%), grade 3 in 13 (14%) and grade 4 in 0 (0%). Renal dysfunction was reversible in more than 90% of patients. Only 6 patients (8%) suffered a certain amount of permanent function loss. More severe acute renal dysfunction occurred in patients who were experiencing hypertension prior to treatment, those who suffered sepsis during treatment and in men than in women. Sepsis was also associated with irreversible function loss. Other variables such as age, performance status, diabetes mellitus, interval between nephrectomy and start of IL-2 therapy and hypotension during treatment were not important. In conclusion, with high-dose IL-2, renal dysfunction develops in almost every patient and such abnormalities are mostly reversible. Predictors for severe acute renal dysfunction are pre-existing hypertension, sepsis and sex. A septic episode also carries a risk of permanent damage. Received: 10 December 1998 / Accepted: 20 May 1999     

Purification and properties of a novel recombinant human hybrid interferon, σ-4 α2/α1

The human interferon (huIFN) σ-4 α2_5–62/α1_64–166 is a genetically engineered hybrid that consists of residues 5–62 of huIFN α2 and residues 64–166 of huIFN α1. This variant contains four cysteine residues at positions 29, 86, 99 and 139, but does not contain the cysteine at position 1 that is characteristic of naturally occurring huIFN α subtypes. This novel recombinant hybrid was purified fromEscherichia coli to greater than 95% homogeneity. The purification was based on ethanol extraction of a trichloroacetic acid precipitate and Matrex Gel Blue A chromatography followed by either a selective precipitation or DEAE-Sepharose chromatography. The purified protein that was treated with 2-mercaptoethanol exhibited two closely migrating bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with apparent molecular weight values of 17 800 and 17 100, both of which exhibited antiviral activity. Electrophoresis performed without prior reduction with 2-mercaptoethanol indicated only a minor extent of intermolecular disulfide bonding. The purified protein exhibited a high specific antiviral activity of 7·10⁷ units/mg when assayed on human fibroblast cells and, in distinction to the parental huIFN α2, it also demonstrated antiviral activity on murine L929 cells. The level of antiproliferative activity of huIFN δ-4 α2_5–62/α1_64–166 on various cell lines of different histological origin appeared to be more comparable to that of huIFN α1 than huIFN α2. The data suggest that huIFN δ-4 α2_5–62/α1_64–166 hybrid may be a useful tool for understanding huIFN structure-function relations.     

Interactions among type I and type II interferon, tumor necrosis factor, and β-estradiol in the regulation of immune response-related gene expressions in systemic lupus erythematosus

Introduction  

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by various clinical manifestations. Several cytokines interact and play pathological roles in SLE, although the etiopathology is still obscure. In the present study we investigated the network of immune response-related molecules expressed in the peripheral blood of SLE patients, and the effects of cytokine interactions on the regulation of these molecules.     

Recombinant human interferon γ exerts an anti-proliferative effect and modulates the expression of human leukocyte antigens A,B,C and DR in human urothelial cell lines

Summary In this study we have treated three malignant (TGrIII) and two pre-malignant (TGrII) urothelial cell lines with recombinant human interferon (rHu-INF). The malignant cells (HCV29-T112C1, Hu1703He and T24) were inhibited in growth by more than 50% after treatment with 100–1000 units of rHu-INF/ml for 4 days as compared to untreated controls. The growth of the pre-malignant cell lines (HCV29 and Hu609) was not influenced to the same extent in the presence of rHu-INF in the culture medium. Treatment with rHu-INF increased the expression of monomorphic human leukocyte antigens (HLA) A,B,C as well as ₂-microglobulin in all the cell lines tested, as demonstrated using a quantitative immunofluorescence assay. The tumourigenic cell lines increased their expression of HLA in a dose-dependent way, whereas treatment of the non-tumourigenic cells with higher concentrations of rHu-INF than 10 units/ml, did not increase the HLA-A,B,C expression further. None of the cell lines expressed HLA-DR unless treated with rHu-INF. No correlation between tumourigenicity and the dose of rHu-INF required for de novo induction of HLA-DR could be demonstrated. After removal of rHu-INF from the medium, the expression of HLA-DR gradually decreased in less than 14 days, indicating that the expression of HLA-DR is not constitutive but dependent upon the presence of rHu-INF. We conclude that human urothelial cells grown in vitro are sensitive to the anti-proliferative and major-histocompatibility-complex-modulating effects of rHu-INF, and that malignant urothelial cells are more sensitive than pre-malignant cells. Finally, our data indicate a possible role for rHu-INF in the management of human bladder cancer.     

Neutrophils and interferon-α-producing cells: who produces interferon in lupus?

Interferon-α plays a crucial role in the pathogenesis of systemic lupus erythematosus. Nevertheless, the different human cell types producing this cytokine as well as the stimuli inducing its production have not been completely characterized. So far, a subpopulation of dendritic cells activated by immune complexes has been identified as major producers of interferon-α in patients with lupus. However, those cells represent a minor population and some studies have reported the secretion of interferon-α by other cells. On the other hand, more than 50% of blood leukocytes are neutrophils and their functions are still not fully understood. Recent data suggest that neutrophils, though usually not considered interferon-α-producing cells, may represent an unexpected source of this cytokine in response to some lupus stimuli.     

Synergistic effects of TGIF and interferonγ (IFN-γ) on tumor cell growthTGIF and IFN-γ

Interferon- (IFN-) and tumor growth inhibitory factor (TGIF) were inducedin vitro in the supernatant from mixed culture of human peripheral blood mononuclear cells (PBMC) and OK-432. TGIF activity was determined by growth inhibition of a human gastric adenocarcinoma cell line, MK-1 cells, and IFN- activity was measured by radioimmunoassay. The production of TGIF and IFN- was time-dependent, reaching its maximum around 48 hrs. Although there was no significant correlation between TGIF production and IFN- production, combination of a subthreshold concentration of recombinant IFN- (rIFN-) and TGIF induced significant growth inhibition of MK-1 cells. This fact indicates that the effects of rIFN- and TGIF are synergistic. The antiproliferative effect of these cytokines are highly species-specific, and their synergistic effects were also species-specific. rIFN--sensitive and -resistant clones were successfully established from the original MK-1 cell line; those clones are both sensitive to TGIF. Synergistic antiproliferative effects were found when the rIFN--sensitive clone, but not the resistant clone, was used as a target, suggesting that the synergistic effects require the target cells' sensitivity to IFN-. These results indicate that the synergistic effects of TGIF and IFN- may produce a clinical antitumor action in cancer patients receiving OK-432 administration.