Serum IFN-α Levels Research Articles

Controlled release recombinant human interferon‐α2b for treating patients with chronic hepatitis C genotype 1: a phase 2a clinical trial

Better convenience and tolerability and sustained therapeutic concentrations might improve interferon (IFN) treatment for chronic hepatitis C virus (HCV) infection. In an open-label, randomized study, controlled release free (chemically unmodified) recombinant human IFN-α(2b) in poly(ether-ester) microspheres (CR-rhIFN-α(2b)), was injected at doses of 160, 320, 480 or 640 μg every 2 weeks for 12 weeks with concomitant weight-based oral ribavirin in 32 treatment-naïve patients with chronic HCV genotype 1. Treatment was well tolerated, with 31 patients (97%) successfully completing the study. Full doses of CR-rhIFN-α(2b) were administered on 96% of scheduled occasions. Flu-like symptoms were generally mild and brief. Injection site reactions developed in 13 patients (41%), and neutropenia occurred in six of eight patients receiving 640 μg. In the 320, 480 and 640 μg groups, 62-75% of patients achieved a ≥2 log(10) HCV RNA reduction by 4 weeks and 88-100% by 12 weeks. For those groups, the pooled median time to ≥2 log(10) reduction was 11 days (95% confidence interval, 7-35 days). In those groups, viral reduction below the limit of detection was accomplished in 25% of patients by 4 weeks and in 62% by 12 weeks. The 160-μg dose was less potent. After CR-rhIFN-α(2b) injection, stable plateau levels of serum IFN-α(2b) were generally reached within 72 h. Treatment-emergent neutralizing antibodies to IFN-α(2b) were observed in one patient. No antibodies to host plant proteins were detected. CR-rhIFN-α(2b) with ribavirin cotherapy was well tolerated and displayed potent early antiviral activity in patients with chronic HCV genotype 1.

Serum levels of IFN-α do not correlate with disease activity in patients with dermatomyositis/polymyositis

IntroductionRecent studies show an important role of type I interferon (IFN) in the proinflammatory process leading to disease manifestations in muscle tissue in patients with polymyositis (PM) and dermatomyositis (DM).AimTo...

Clinical Utility of Serum Interleukin-8 and Interferon-Alpha in Thyroid Diseases

Serum interleukin-8 (IL-8) and interferon-alpha (IFN-α) levels have been estimated from a total of 88 individuals of which 19 were disease-free healthy individuals, and 69 were patients with thyroid diseases: goitre (N = 21), autoimmune diseases (N = 16), and carcinomas (N = 32). Both IL-8 and IFN-α were significantly higher in all the patients as compared to healthy individuals. Serum IL-8 levels showed significant positive correlation with disease stage in thyroid cancer patients. Higher serum IL-8 levels were associated with advanced disease stage while no significant correlation was observed between serum IFN-α levels and any of the clinicopathological parameters. IL-8 and IFN-α significantly correlated with each other in anaplastic carcinoma patients. Finally concluding, monitoring the serum IL-8 and IFN-α levels can help differentiate patients with thyroid diseases from healthy individuals, and IL-8 seems to have a role in the pathogenesis of thyroid diseases and may represent a target for innovative diagnostic and therapeutic strategies.

Innate immune responses to human rotavirus in the neonatal gnotobiotic piglet disease model

Intestinal and systemic dendritic cell (DC) frequencies, serum and small intestinal content cytokines and uptake/binding of human rotavirus (HRV) virus-like particles (VLP) were studied in HRV acutely infected or mock-inoculated neonatal gnotobiotic piglets. Intestinal, mesenteric lymph node (MLN) and splenic plasmacytoid DCs (pDCs), conventional DCs (cDCs) and macrophages/monocytes were assessed by flow cytometry. In infected pigs, serum and small intestinal content interferon-α (IFN-α) were highest, interleukin-12 (IL-12) was lower and IL-10, tumour necrosis factor-α and IL-6 were minimal. Compared with mock-inoculated piglets, frequencies of total intestinal DCs were higher; splenic and MLN DC frequencies were lower. Most intestinal pDCs, but few cDCs, were IFN-α(+) and intestinal macrophages/monocytes were negative for IFN-α. Serum IFN-α levels and IFN-α(+) intestinal pDCs were highly correlated, suggesting IFN-α production in vivo by intestinal pDCs (r=0·8; P<0·01). The intestinal pDCs and cDCs, but not intestinal macrophages/monocytes, of HRV-infected piglets showed significantly lower VLP uptake/binding compared with mock-inoculated piglets, suggesting higher activation of pDCs and cDCs in infected piglets. Both intestinal pDCs and cDCs were activated (IFN-α(+) and lower VLP binding) after HRV infection, suggesting their role in induction of HRV-specific immunity. Dose-effects of HRV on serum IFN-α and IFN-α(+) DCs were studied by infecting piglets with 100-fold higher HRV dose. A high dose increased parameters associated with inflammation (diarrhoea, intestinal pathology) but serum IFN-α and IFN-α(+) DCs were similar between both groups. The pDCs have both anti- and pro-inflammatory functions. Stimulation of the anti-inflammatory effects of pDCs after the high dose, without increasing their pro-inflammatory impacts, may be critical to reduce further immunopathology during HRV infection.

Type I interferon system activation and association with disease manifestations in systemic sclerosis

ObjectivesTo study the presence of interferogenic autoantibodies in systemic sclerosis (SSc) and their correlation with clinical manifestations, serum levels of interferon α (IFNα) and chemokines of importance in the disease...

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

IntroductionPlasmacytoid 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.MethodsWe 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.ResultsHere 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.ConclusionsThese 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.

Effect of Interferon-alpha in systemic lupus erthematosus (SLE) serum on the differentiation and maturation of dendritic cells derived from CD34 + hematopoietic precursor cells

Objective To study the effect of interferon-alpha IFN-α in the serum of SLE patients on the differentiation and maturation of dendritic cells (DCs) derived from CD34 + hematopoietic precursor cells (HPCs). Methods Serum samples from SLE patients and normal controls were collected and the concentration of IFN-α detected by ELISA. CD34 +HPCs were purified from cord blood by a magnetic cell sorting system (MACS), and cultured to differentiate to DCs. Normal serum, normal serum with exogenous IFN-α, SLE serum with raised levels of IFN-α, or SLE serum with anti-IFN-α neutralizing antibody was added to the culture medium. The phenotype of DCs was analyzed by flow cytometry (FCM) and the capacity of DCs to stimulate allogenic T lymphocyte proliferation was evaluated in a mixed lymphocyte reaction by the Cell Counting Kit-8. Cytokine production was assessed by ELISA. Results Serum levels of IFN-α were significantly higher in SLE patients than in normal controls and this correlated positively with disease activity. Cultured in SLE serum with raised levels of IFN-α, CD34 + HPCs could differentiate into DCs that expressed higher levels of HLA-DR, CD80 and CD86, and showed an enhanced allogenic T-cell stimulatory capacity, while producing lower levels of IL-12 and higher amounts of IL-10 compared with those DCs cultured in normal serum. Conclusion Increased levels of IFN-α in SLE serum promotes the differentiation and maturation of DCs derived from CD34 + HPCs and could contribute to the pathogenesis of SLE.

Adenovirus-Mediated Expression of Interferon-α Delays Viral Replication and Reduces Disease Signs in Swine Challenged with Porcine Reproductive and Respiratory Syndrome Virus

In this study, pigs were injected with a nonreplicating human adenovirus type 5 vector expressing porcine interferon-alpha (Ad5-pIFN-alpha) and then challenged with porcine reproductive and respiratory syndrome virus (PRRSV) to determine whether the presence of increased levels of IFN-alpha would decrease viral replication and/or disease. Groups of 10 pigs each were inoculated with Ad5-pIFN-alpha and not challenged, Ad5-pIFN-alpha and challenged with PRRSV 1 d later, or inoculated with a control adenovirus that does not express IFN-alpha (Ad5-null) and challenged 1 d later with PRRSV. IFN-alpha levels in all pigs inoculated with the Ad5-pIFN-alpha were elevated the day of challenge (1 d after inoculation), but were undetectable by 3 d after inoculation in the pigs that were not challenged with PRRSV. Pigs inoculated with Ad5-pIFN-alpha and challenged with PRRSV had lower febrile responses, a decreased percentage of lung involvement at 10 d post-infection, delayed viremia and antibody response, and higher serum IFN-alpha levels as a result of PRRSV infection, compared to pigs inoculated with Ad5-null and challenged with PRRSV. These results indicate that IFN-alpha can have protective effects if present during the time of infection with PRRSV.

Establishment of Sjögren's syndrome models by immunization with alpha-Fodrin: experiment with mice

To explore the possibility to establish Sjögren's syndrome models by immunizing mice with alpha-fodrin. Twenty-four 4-week-old BALB/C mice were randomly divided into 4 equal groups to undergo subcutaneous injection of alpha-Fodrin, submaxillary gland homogenate and glutathione S-transferase (GST) or phosphate-buffered saline (PBS) (negative control groups) on days 0, 14, 35, and 56 respectively. The drinking amount of water was measured. Blood samples were collected every 2 - 3 weeks. Munofluorescence assays and ELISA were used to examine the presence of anti-Fodrin, anti-type 3 muscarinic acetylcholine receptor polypeptide (M3RP), anti-SSA, anti-SSB, rheumatoid factor (RF), and antinuclear antibody (ANA). Immunochemistry was used to detect the levels of interferon (IFN)-gamma, interleukin (IL)-2, and IL-10. One mouse was killed from each group every 2 - 3 weeks. The salivary glands were examined. (1) No auto-immune antibody was found in the serum samples of the mice before immunization. Antibodies against alpha-Fodrin and M2RP, and ANA were positive in the serum samples of the alpha-Fodrin and submaxillary gland homogenate groups since the 35th day after immunization, and were all negative in the 2 control groups. However, no antibodies against SSA, SSB and RF were found in all 4 groups. (2) Lymphocytic infiltration could be seen in the salivary glands of the immunized animals since 50th days after the first immunization of alpha-Fodrin and submaxillary gland homogenate. Immunohistochemistry showed alpha-Fodrin expression in the submaxillary glands of the alpha-Fodrin and submaxillary gland homogenate groups, but not in the PBS and GST controls. (3) The serum IFN-alpha levels of the alpha-Fodrin and submaxillary gland homogenate groups were (81.6 +/- 7.1) and (90.5 +/- 4.9) pg/ml respectively, both significantly higher than those of the GST and PBS groups [(30.1 +/- 5.9) and (19.3 +/- 6.4) pg/ml respectively, both P < 0.05]. The serum IL-2 levels of the alpha-Fodrin and submaxillary gland homogenate groups were (18.7 +/- 2.3) and (19.8 +/- 0.9) pg/ml respectively, both significantly higher than those of the GST and PBS groups [(4.9 +/- 1.1) and (3.5 +/- 1.6) pg/ml respectively, both P < 0.05]. No difference was found in the level of serum IL-10 among the 4 groups. (4) There was no significant difference in the volume of water volume drunk among the 4 groups. (1) It is possible to establish mouse mice SS models by immunization with alpha-Fodrin or submaxillary gland homogenate that are reminiscent of human SS. (2) The appearance of multiple antibodies may be related to the antigen epitope spreading. (3) The pathogenesis of SS may be related to Th1 type response.

Increased Interferon Alpha Expression in Circulating Plasmacytoid Dendritic Cells of HIV-1-Infected Patients

The role of plasmacytoid dendritic cells (pDC) and interferon alpha (IFN alpha) in HIV-1 infection is still unclear. On one hand, HIV-1 disease is associated with a progressive decline of pDC, which displays reduced ability to produce IFN alpha after in vitro challenge. On the other hand, high IFN alpha serum levels in HIV-1-infected individuals have been proposed to promote immune hyper-activation and disease progression. We sought to determine whether disappearance of pDC in HIV-1 disease is due to homing in lymphoid tissues. We also studied IFN alpha and myxovirus resistance protein A (MxA) expression in unstimulated pDC and correlated these results with selected clinical and laboratory parameters. We found that pDC decline markedly in peripheral blood of patients progressing to disease but at the same time express much higher levels of IFN alpha and MxA compared to control individuals. On the other hand, we observed steady pDC counts in lymph nodes of HIV-1 patients. The frequency of circulating pDC correlated directly with CD4 cell counts and inversely with viral load. However, we found no correlation between IFN alpha and MxA expression levels, CD4 counts, and viral load. Circulating pDC decline sharply in the course of HIV-1 disease, but express high levels of IFN alpha, which may represent a hallmark of systemic immune dysfunction.

Does serum alpha interferon measurement aid in the etiological diagnosis of febrile adult patients?

In febrile patients, distinguishing bacterial from viral infections is crucial for early treatment initiation and rational use of antibiotics. Raised interferon-alpha (IFN-alpha) levels in serum has been associated with a wide range of viral infections. We evaluated the effectiveness of IFN-alpha serum measurements for the etiological diagnosis of febrile patients. Adult patients who were attending the emergency department with body temperature above or equal to 38.5 degrees C were studied prospectively, followed-up until day 30, and classified by two independent experts (blind for IFN-alpha results) as having a bacterial/parasitic infection, viral infection, or other diagnosis. The results of IFN-alpha measurements in blood samples taken in the emergency room, were compared with expert diagnosis. Among 243 patients included, 167 had bacterial/parasitic infections (including 19 with viral co-infection), 59 had viral infections, and 36 other diagnoses. IFN-alpha assay had a sensitivity of 0.44 and a specificity of 0.92 for the diagnosis of viral infection. Among the 20 patients with acute viral infection according to the emergency physician diagnosis, 7 (35%) were given antibiotics, including four patients with raised IFN-alpha concentrations. It is concluded that in febrile patients, raised serum IFN-alpha level is highly specific of the viral etiology of fever but poorly sensitive. Reliable viral and bacterial biological markers are needed in order to improve rational use of antibiotics.

Antagonizing HMGB1 inhibits proteinuria in a murine model of lupus-like disease (131.24)

Abstract High mobility group box 1 (HMGB1) is an abundant chromatin protein that acts like an inflammatory cytokine when it is released by dying or stimulated cells. Elevated levels are detected at sites of inflammation in a number of autoimmune disorders including SLE. In addition, HMGB1 has been shown to contribute to the activation of plasmacytoid dendritic cells as well as B cells, cell types that are implicated in the pathogenesis of SLE. To address the role of HMGB1 in experimental lupus, we investigated the protective efficacy of a fully humanized mAb (IA-4, which recognizes both mouse and human HMGB1) in an IFNα-accelerated lupus model. In this model, adenovirus IFNα-treated NZB/W F1 mice exhibit 90–100% proteinuria incidence at 4–6 weeks post-treatment. The functionality of IA-4 has been demonstrated in vitro by its ability to inhibit rHMGB1-induced IL-6 secretion in human PBMC (IC50 = 0.9 nM). Prophylactic administration of the anti-HMGB1 mAb IA-4 at 10 mg/kg significantly inhibited the proteinuria severity score at seven weeks (65% inhibition; p&amp;lt;0.05 compared to an isotype control). Consistent with the proteinuria data, histopathological assessment of the kidney also revealed protection with IA-4 treatment. Despite its protection in nephritis, IA-4 treatment showed no detectable effect on serum levels of IFN-α and autoantibodies against dsDNA or SSA/Ro. Taken together, these data suggest that HMGB1 is a critical effector molecule in lupus nephritis and that anti-HMGB1 treatment may provide a potential therapeutic benefit for the treatment of SLE.

The genetics and biology of Irf5-mediated signaling in lupus

Recently much attention was attracted to the importance of the type I interferon pathway in the initiation and development of the autoimmune disease systemic lupus erythematosus (SLE). Many SLE patients have increased serum levels of IFN-α and display an IFN gene expression “signature” characterized by strong overexpression of IFN-responsive genes in leukocytes and target tissues. Moreover, about 20% of cancer patients treated with IFN-α therapy manifest symptoms resembling SLE and some later develop the disease. One of the key genes of the IFN-α pathway, IRF5, was found to be strongly associated with SLE. Two functional SNPs lead to alternative splicing and altered steady-state level of IRF5 gene expression. Besides, the gene has a polymorphic inserion/deletion in exon 6, which contributes to the diversity in the isoform pattern of IRF5. Interestingly, recent studies have not found association of IRF5 with the other autoimmune diseases, such as rheumatoid arthritis or psoriasis, suggesting the unique role for IRF5 in the development of lupus. Here, we present the current knowledge on IRF5 genetics and its biological function and discuss the possible ways in which IRF5 contributes to susceptibility to SLE.

Distinct expression pattern of IFN- and TNF- in juvenile idiopathic arthritis synovial tissue

Recent laboratory and clinical data suggest that two prototype autoimmune diseases, systemic lupus erythematosus and rheumatoid arthritis are mainly driven by distinct cytokines, interferon (IFN)-alpha and tumour necrosis factor (TNF)-alpha, respectively. We here investigated the presence and characteristics of natural type I IFN-producing cells (IPCs), as well as IFN-alpha and TNF-alpha expression at sites of inflammation in juvenile idiopathic arthritis (JIA). Peripheral blood (PB) and synovial fluid (SF) mononuclear cells (MNCs) (n = 25 each) from JIA patients with active disease were studied. IPCs were identified as BCDA-2(+)CD123(+)HLA-DR(+)CD45RA(+) cells, and dendritic cells (DCs) as CD11c(+)CD14(-/low)lin(-) cells by flow cytometry. IPCs and DCs were analysed for Toll-like receptor-7 and -9 mRNA expression by real-time polymerase chain reaction. IFN-alpha was measured by enzyme-linked immunosorbent assay in serum, SF and in supernatants of influenza virus-infected, cultured IPCs. Synovial tissues of n = 6 additional JIA patients were analysed by immunohistochemistry using mAbs against CD123, IFN-alpha, TNF-alpha, CD3, CD19 and CD138. IPCs were enriched in SF MNCs compared with PB MNCs in all JIA patients. Influenza-induced, but no spontaneous IFN-alpha release was detected from SF IPCs, and serum and SF IFN-alpha levels were not elevated. Nonetheless, in synovial tissue IFN-alpha producing cells accumulated at inflammatory lymph-follicular-like structures, while TNF-alpha producing cells were mostly found at the lining and sublining layers. These data suggest that besides TNF-alpha-expressing cells, IFN-alpha-producing IPCs are involved in initiation, maintenance or regulation of the inflammatory response in JIA.

Characterization of conventional and plasmacytoid dendritic cells in swine secondary lymphoid organs and blood

Dendritic cells (DCs) act as antigen presenting cells that bridge innate and adaptive immune systems with the unique capacity to initiate primary T-cell responses and efficiently stimulate memory responses. In pig, little information is available about these cells in secondary lymphoid organs, the place where T cell activation usually occurs. As increased knowledge on DC is a necessary prerequisite to further understand their role in response to microbial infection or in protection after vaccination, we investigated the DC types that would be present in tonsil, spleen and non-subcutaneous lymph nodes in the steady state. One population was composed of CD172a +CD11R1 +CD1 +/−CD80/86 +/− cells and would correspond to conventional DCs (cDC), while the other one was composed of CD172a +CD4 +CD1 +/−CD80/86 +/− cells and would correspond to plasmacytoid DCs (pDC). These subsets were also detected in blood but spleen was the tissue with the higher frequency of such DCs. In lymphoid organs, most of cDC and pDC were in an immature status, as revealed by the low percentage of cells expressing the co-stimulatory molecule CD80/86. However, expression of that marker by 5% of DCs in organs and up to 15% in blood, together with lower expression of CD1a and expression of CD208, would indicate a partial activation and/or semi-maturation. Interestingly, 8% of tonsil pDC and 15% of blood pDC were shown to secrete IFN-α, while 18–20% of cDC expressed TNF-α in these tissues. Both cell types also expressed IL-12 and IL-10 in the steady state. Measurements of IFN-α, TNF-α, IL-12 and IL-10 levels in serum confirmed their production within immune homeostasis, whereas IL-6, IL-18 and IFN-γ could not be detected. Altogether, these data complete knowledge on porcine immune system cells and will be a useful tool for further in vivo studies on porcine DC role in peripheral tolerance induction and in immune responses to pathogens.

Cytokine and C-Reactive Protein Profiles Induced by Porcine Circovirus Type 2 Experimental Infection in 3-Week-Old Piglets

The purpose of this study was to determine serum profiles of cytokines at a protein level and Creactive protein (CRP) during the development of postweaning multisystemic wasting syndrome (PMWS) in experimentally inoculated pigs. Levels of serum IFN-alpha, IL-6, IL-10, and CRP were examined for a 35-day period in 10 piglets experimentally infected with PCV2 at 3 weeks of age. Four of the infected piglets developed severe PMWS at 14 to 21 days post-infection (d.p.i.) and died prior to termination of the experiment. The remaining six PCV2-infected piglets experienced transient fever, but did not display overt clinical signs of PMWS and were considered as subclinically infected. A bioassay was used to detect IL-6 and ELISAs were used to detect IFN-alpha, IL-10, and CRP. There were no significant differences in cytokine or CRP expression from 0 to 7 d.p.i. between the PMWS-affected and the subclinically infected piglets. Levels of IL-10 and CRP were elevated from 10 and 14 d.p.i. respectively in the PMWS-affected piglets compared to the subclinically infected piglets. There were no significant differences in IFN-alpha and IL-6 expression between the PMWS-affected piglets and the subclinically infected piglets. The present study shows that elevated levels of serum CRP and IL-10 were associated with PCV2-infected piglets that subsequently developed severe PMWS. This may help to provide further insight into the immunoaetiogenesis of this syndrome.

IκB kinase-α is critical for interferon-α production induced by Toll-like receptors 7 and 9

The Toll-like receptor (TLR) family has important roles in microbial recognition and dendritic cell activation1,2. TLRs 7 and 9 can recognize nucleic acids3,4,5,6 and trigger signalling cascades that activate plasmacytoid dendritic cells to produce interferon-α (IFN-α) (refs 7, 8). TLR7/9-mediated dendritic cell activation is critical for antiviral immunity but also contributes to the pathogenesis of systemic lupus erythematosus, a disease in which serum IFN-α levels are elevated owing to plasmacytoid dendritic cell activation8,9. TLR7/9-induced IFN-α induction depends on a molecular complex that contains a TLR adaptor, MyD88, and IFN regulatory factor 7 (IRF-7) (refs 10–14), but the underlying molecular mechanisms are as yet unknown. Here we show that IκB kinase-α (IKK-α) is critically involved in TLR7/9-induced IFN-α production. TLR7/9-induced IFN-α production was severely impaired in IKK-α-deficient plasmacytoid dendritic cells, whereas inflammatory cytokine induction was decreased but still occurred. Kinase-deficient IKK-α inhibited the ability of MyD88 to activate the Ifna promoter in synergy with IRF-7. Furthermore, IKK-α associated with and phosphorylated IRF-7. Our results identify a role for IKK-α in TLR7/9 signalling, and highlight IKK-α as a potential target for manipulating TLR-induced IFN-α production.

Efficient delivery of small interfering RNA to bone-metastatic tumors by using atelocollagen in vivo

Silencing of gene expression by small interfering RNAs (siRNAs) is rapidly becoming a powerful tool for genetic analysis and represents a potential strategy for therapeutic product development. However, there are no reports of systemic delivery for siRNAs toward treatment of bone-metastatic cancer. Accordingly, we report here that i.v. injection of GL3 luciferase siRNA complexed with atelocollagen showed effective reduction of luciferase expression from bone-metastatic prostate tumor cells developed in mouse thorax, jaws, and/or legs. We also show that the siRNA/atelocollagen complex can be efficiently delivered to tumors 24 h after injection and can exist intact at least for 3 days. Furthermore, atelocollagen-mediated systemic administration of siRNAs such as enhancer of zeste homolog 2 and phosphoinositide 3'-hydroxykinase p110-alpha-subunit, which were selected as candidate targets for inhibition of bone metastasis, resulted in an efficient inhibition of metastatic tumor growth in bone tissues. In addition, upregulation of serum IL-12 and IFN-alpha levels was not associated with the in vivo administration of the siRNA/atelocollagen complex. Thus, for treatment of bone metastasis of prostate cancer, an atelocollagen-mediated systemic delivery method could be a reliable and safe approach to the achievement of maximal function of siRNA.

Absorption of interferon alpha from patches in rats

Interferon alpha (IFN-α), patch preparations composed of three layers, water-insoluble backing layer, drug containing layer with absorption enhancer and surface layer containing pH-dependent polymer were prepared. As absorption enhancer, three surfactants, Gelucire44/14 (Lauroyl macrogol-32 glycerides), Labrasol (Caprylocaproyl macrogol-8 glycerides) and HCO-60 (polyoxyethylated hydrogenerated castor oil) were used in preparing IFN-α patch preparations. The intestinal absorption of IFN-α was studied after the administration of test patch preparations into the rat jejunum, 50,000 IU/kg. The serum IFN-α levels were measured by an ELISA method and both Cmax and AUC were determined as the index of absorption of IFN-α. Gelucire44/14 preparation including Pharmasol for the stable solidification showed the higher Cmax, 7.66 ± 0.82 IU/ml, and AUC, 12.85 ± 1.49 IU h/ml, than Labrasol (6.51 ± 0.89 and 8.30 ± 1.34 IU h/ml) and HCO-60 (6.02 ± 1.14, 7.53 ± 1.84 IU h/ml) preparations, respectively. By comparing to the AUC obtained after s.c. injection of the same dose of IFN-α to rats, bioavailability (BA) was estimated to be 7.8% in Gelucire44/14 preparation. In vitro release study showed that the T50%s, the time when half of the formulated IFN-α is released from the patches, were 3.4 ± 0.1 min for HCO-60, 7.8 ± 0.1 min for Gelucire44/14 and 11.4 ± 0.1 min for Labrasol preparations. To study the effect of absorption site, Gelucire44/14 preparation was administered into the rat duodenum and ileum. However, there were not significant differences on AUC among the three absorption sites. By reducing the IFN-α dose from 50,000 to 25,000 IU/kg, the serum IFN-α levels vs time profile showed a tendency of dose-dependency. When the histological examination of small intestinal mucosa was carried out in this study, the small intestinal mucosa after the Gelucire44/14 patches administered and before it was administered, could not recognize impaired. From these results, the usefulness of oral patch system for the oral delivery of IFN-α has been proved in rats.

Heterophile antibodies masquerade as interferon-alpha in subjects with new-onset type 1 diabetes.

One of the potential environmental triggers in type 1 diabetes may be viruses. The mechanism of viral infections leading to β-cell destruction of the pancreas is becoming clearer, and the potential role of viruses inducing the cytokine interferon-α (IFN-α) has been implicated. It is well established that IFN-α therapy induces islet cell autoimmunity and other endocrine autoantibodies as well (1). Recent studies have indicated that IFN-α levels in serum of new-onset type 1 diabetic subjects are elevated and perhaps related to recent enteroviral infections (2,3). These studies suggest that IFN-α may be a useful surrogate marker for disease onset, perhaps due to a recent viral infection or vaccination. At the Barbara Davis Center for Childhood Diabetes in Denver, Colorado, we screened 32 new-onset type 1 diabetic subjects and 31 …