Interleukin (IL)-<em>3</em>2 is a recently described proinflammatory cytokine characterized by the induction of nuclear factor (NF)-kappaB activation. We studied IL-<em>3</em>2 expression in human pancreatic tissue and pancreatic cancer cell lines. Tissue samples were obtained surgically. IL-<em>3</em>2 expression was evaluated by standard immunohistochemical procedures. IL-<em>3</em>2 mRNA expression was analyzed by Northern blotting and real time PCR analyses. IL-<em>3</em>2 was weakly immunoexpressed by pancreatic duct cells. In the inflamed lesions of chronic pancreas, the ductal expression of IL-<em>3</em>2 was markedly increased. A strong expression of IL-<em>3</em>2<em>alpha</em> was detected in the pancreatic cancer cells. In pancreatic cancer cell lines (PANC-1, MIA PaCa-2, and BxPC-<em>3</em> cells), the expression of IL-<em>3</em>2 mRNA and protein was enhanced by IL-1beta, <em>interferon</em> (IFN)-gamma, and tumor necrosis factor (TNF)-<em>alpha</em>. An inhibitor of phosphatidylinositol <em>3</em>-kinase (LY294002) significantly suppressed the IL-1beta-, IFN-gamma- and TNF-<em>alpha</em>-induced IL-<em>3</em>2 mRNA expression. The blockade of NF-kappaB and activated protein-1 activation markedly suppressed the IL-1beta-, IFN-gamma-, and/or TNF-<em>alpha</em>-induced IL-<em>3</em>2 mRNA expression. Furthermore, IL-<em>3</em>2-specific small interfering RNA significantly decreased the uptake of [<em>3</em>H]thymidine and increased the annexin V-positive population (apoptotic cells) in PANC-1 cells. IL-<em>3</em>2 knockdown also suppressed the mRNA expression of antiapoptotic proteins (Bcl-2, Bcl-xL, and Mcl-1). Pancreatic duct cells are the local source of IL-<em>3</em>2, and IL-<em>3</em>2 may play an important role in inflammatory responses and pancreatic cancer growth.

The signal transduction pathways that lead activated natural killer (NK) cells to produce cytokines, releases cytotoxic granules, or do both, are not clearly dissected. For example, phosphoinositide <em>3</em>-kinases (PI<em>3</em>Ks) are key players in the execution of both functions, but the relative contribution of each isoform is unknown. We show here that the catalytic isoform p110delta, not p110gamma, was required for <em>interferon</em>-gamma (IFN-gamma), tumor necrosis factor-<em>alpha</em> (TNF-<em>alpha</em>), and granulocyte macrophage colony-stimulating factor (GM-CSF) secretion, whereas neither was necessary for cytotoxicity. Yet, when both p110delta and p110gamma isoforms were inactivated by a combination of genetic and biochemical approaches, cytotoxicity was decreased. NK-cell numbers were also affected by the lack of p110delta but not p110gamma and more severely so in mice lacking both subunits. These results provide genetic evidence that p110delta is the dominant PI<em>3</em>K isoform for cytokine secretion by NK cells and suggest that PI<em>3</em>Ks cooperate during NK-cell development and cytotoxicity.

Footpad swelling developing in mice after local injection of LPS (S. marcescens) was found to consist of two phases with peaks occurring on days 2 to <em>3</em> and 6 to 8, respectively. Histopathologically, the reaction was characterized by edema and mononuclear cell infiltration; the second peak was associated with intravascular thrombosis as is typically described for the Shwartzman reaction to LPS. Recombinant DNA-derived IFN-gamma, administered by i.p. injection, had a suppressive effect on the development of the reaction. The same effect was seen with recombinant DNA-derived IFN-<em>alpha</em> 1 and with the natural mixture of IFN-<em>alpha</em> and -beta. In mice pretreated with neutralizing monoclonal antibodies to IFN-gamma, the footpad response to LPS was modified in that a delayed monophasic rather than a biphasic response occurred. These data indicate that LPS induces local production of IFN-gamma, which acts as a trigger or positive regulator of the reaction. The effect of a single pretreatment with neutralizing anti-IFN-gamma antibody was found to last for as long as 6 wk. Experiments in which antibody administration was delayed till after LPS challenge indicated that endogenous IFN-gamma was also involved in the late phases of the inflammation. The results show that regulation of inflammation by <em>interferons</em> is complex in that local IFN-gamma acts as a positive factor, whereas systemic IFN-<em>alpha</em> 1 and -gamma, probably through indirect mechanisms, downregulate inflammation.

Cytokines play a significant role in the regulation of Toxoplasma gondii in the central nervous system. Cytokine-activated microglia are important host defense cells in central nervous system infections. Recent evidence indicates that astrocytes can also be activated by cytokines to inhibit intracellular pathogens. In this study, we examined the effect of gamma <em>interferon</em> (IFN-gamma), tumor necrosis factor <em>alpha</em> (TNF-<em>alpha</em>), interleukin-6 (IL-6), and IL-1 on the growth of T. gondii in a primary murine astrocyte culture. Pretreatment of astrocytes with IFN-gamma resulted in 65% inhibition of T. gondii growth. Neither TNF-<em>alpha</em>, IL-1, nor IL-6 alone had any effect on T. gondii growth. IFN-gamma in combination with either TNF-<em>alpha</em>, IL-1, or IL-6 caused a 75 to 80% inhibition of growth. While nitric oxide was produced by astrocytes treated with these cytokines, inhibition of T. gondii growth was not reversed by the addition of the nitric oxide synthase inhibitor NG-monomethyl-L-arginine. Furthermore, IFN-gamma in combination with IL-1, IL-6, or TNF-<em>alpha</em> also induced inhibition in astrocytes derived from syngeneic mice deficient in the enzyme inducible nitric oxide synthase. This finding suggests that the mechanism of cytokine inhibition is not nitric oxide mediated. Similarly, the addition of tryptophan had no effect on inhibition, indicating that the mechanism was not mediated via induction of the enzyme indoleamine 2, <em>3</em>-dioxygenase. The mechanism of inhibition remains to be elucidated. Results from this study demonstrate that cytokine-activated astrocytes are capable of significantly inhibiting the growth of T. gondii. These data indicate that astrocytes may be important host defense cells in controlling toxoplasmosis in the brain.

<em>Interferon</em> consensus sequence-binding protein (ICSBP) is a transcription factor belonging to the <em>interferon</em> regulatory factor (IRF) family, recently shown to play a critical role in dendritic cell (DC) differentiation. Here, we analyzed the role of ICSBP in the development and trafficking of epidermal Langerhans cells (LCs) and dermal DCs and the implications for initiation of a competent immune response. ICSBP-/- mice exhibited a reduced frequency of LCs and a delayed mobility of DCs from skin that reflected a slower turnover rate in lymph nodes during steady-state conditions. Even under inflammatory changes, ICSBP-/- DCs displayed reduced mobility from skin to lymph nodes and, as a consequence, failed to induce a contact hypersensitivity (CHS) response, suggesting that these DCs were unable to initiate a competent antigen (Ag)-specific T-cell-mediated immunity. Moreover, bone marrow (BM)-derived DCs from ICSBP-/- mice exhibited an immature phenotype and a severe reduction of interleukin 12 (IL-12) expression. These BM DCs also showed a marked defect in their migratory response to macrophage inflammatory protein <em>3</em> <em>alpha</em> (MIP-<em>3</em> <em>alpha</em>), MIP-<em>3</em> beta, and the CC chemokine CCL21/6Ckine, which was paralleled by an impaired expression of the CC chemokine receptors, CCR6 and CCR7. Together, these results indicate that ICSBP is critically required for the development and trafficking of skin DCs, thus playing a critical role in the DC-mediated initiation of T-cell immunity.

The type I <em>interferon</em> (IFN) response represents one of the first lines of defense against influenza virus infections. In this study, we assessed the protective potential of exogenous IFN-<em>alpha</em> against seasonal and highly pathogenic influenza viruses in ferrets. Intranasal treatment with IFN-<em>alpha</em> several hours before infection with the H1N1 influenza A virus strain A/USSR/90/77 reduced viral titers in nasal washes at least 100-fold compared to mock-treated controls. IFN-treated animals developed only mild and transient respiratory symptoms, and the characteristic fever peak seen in mock-treated ferrets 2 days after infection was not observed. Repeated application of IFN-<em>alpha</em> substantially increased the protective effect of the cytokine treatment. IFN-<em>alpha</em> did not increase survival after infection with the highly pathogenic H5N1 avian influenza A virus strain A/Vietnam/120<em>3</em>/2004. However, viral titers in nasal washes were significantly reduced at days 1 and <em>3</em> postinfection. Our study shows that intranasal application of IFN-<em>alpha</em> can protect ferrets from seasonal influenza viruses, which replicate mainly in the upper respiratory tract, but not from highly pathogenic influenza viruses, which also disseminate to the lung. Based on these results, a more intensive evaluation of IFN-<em>alpha</em> as an emergency drug against pandemic influenza A is warranted.

Infection of mouse trigeminal ganglia by herpes simplex virus induces cytokine expression that persists long after infectious virus or viral antigens become undetectable. To examine mechanisms underlying this phenomenon, we used a thymidine kinase mutant, dlsptk, which fails to replicate in ganglia and does not reactivate upon ganglionic explant. Using quantitative reverse transcriptase-polymerase chain reaction assays, we found that levels of <em>interferon</em>-gamma and tumor necrosis factor-<em>alpha</em> transcripts in dlsptk-infected ganglia were lower than those in wild type-infected ganglia, but were significantly (eight- to 10-fold) higher than those in mock-infected ganglia from Day <em>3</em> to Day 100 postinfection. We also studied latency-associated transcript (LAT) negative mutants that exhibit increased expression of productive cycle transcripts in ganglia. Ganglia infected with these mutants contained levels of cytokine transcripts similar to those in wild type-infected ganglia; any increases in viral antigen expression mediated by the LAT deletion were not accompanied by increased cytokine expression. Thus, neither viral replication, the ability to reactivate, nor LAT expression in ganglia is required for persistent elevated cytokine expression. The results provide indirect evidence that low-level expression of viral productive cycle genes in neurons can provide signals that elicit cytokine expression.

We have prepared stable cell lines, derived from Vero cells and A<em>3</em>.01 cells, that express a hybrid human <em>alpha</em> 2-<em>interferon</em> gene under control of the human immunodeficiency virus (HIV) long terminal repeat. These cells constitutively produced low levels (50-150 units/ml) of <em>alpha</em> 2-<em>interferon</em>. However, high levels of <em>interferon</em> (10(<em>3</em>) units/ml) could be induced upon trans-activation by the product of the tat gene (pIIIextatIII), and de novo infection by HIV resulted in a moderate increase (400 units/ml) in <em>alpha</em> 2-<em>interferon</em> synthesis. In contrast to the fully permissive HIV replication, in transfected Vero cells or infected A<em>3</em>.01 cells, the transcription and replication of HIV in Vero or A<em>3</em>.01 cells containing the HIV long terminal repeat--<em>alpha</em> 2-<em>interferon</em> hybrid gene (VN89 and A<em>3</em>N89 cells, respectively) was completely inhibited. These data suggest that virus-trans-activated <em>alpha</em> 2-<em>interferon</em> synthesis can be used as a selective inhibitor of HIV replication.

Immunostimulatory sequences (ISS) are short oligonucleotides containing unmethylated cytosine-phosphate-guanine (CpG) dinucleotides that stimulate innate immune responses through Toll-like receptor-9 on B cells and plasmacytoid dendritic cell (PDC) precursors. The anti-inflammatory cytokine interleukin (IL)-10 is predicted to be a potent inhibitor of many of the activities described for ISS, and this may impact the use of ISS in disease states characterized by elevated IL-10. As the activities of ISS on PDCs are central to many clinical applications of ISS, we have studied the effects of IL-10 on PDC stimulation by <em>3</em> distinct classes of ISS. IL-10 inhibited cytokine production and survival of ISS-activated PDCs; however, IL-12 induction was much more sensitive to inhibition than <em>interferon</em> (IFN)-<em>alpha</em> induction. Within the PDC population are cells that respond to ISS by producing either IL-12 or IFN-<em>alpha</em> but not both cytokines. IL-12-producing PDCs require costimulation through CD40 and appear more mature than IFN-<em>alpha</em>-producing PDCs. The <em>3</em> distinct classes of ISS differed with respect to induction of PDC maturation and T-cell priming capacity. IL-10 regulated PDC activation but did not inhibit the subsequent T-cell-priming ability of PDCs already activated by ISS.

Natural killer T (NKT) cells, a unique subpopulation of T cells, coexpress markers also present on NK cells and recognize the major histocompatibility complex class I-like CD1d1 molecule. We studied the effect of an acute virus infection on NKT cells. Mice were infected with the nonhepatotropic Armstrong strain of lymphocytic choriomeningitis virus (LCMV), and at various times postinfection, mononuclear cells from the liver, peritoneum, and spleen were isolated. It was found that within 2 to <em>3</em> days, there was a selective loss of NKT cells from the liver with an apparent rapid recovery within 8 to 14 days. There was no increase in peritoneal or splenic NKT cells, indicating that NKT cells did not traffic to these tissues. This loss of NKT cells was independent of gamma <em>interferon</em> (IFN-gamma) and interleukin 12 (IL-12) production, but did occur in mice treated with poly(I-C), a classical inducer of IFN-<em>alpha</em>/beta. The reduction in NKT cells was CD28 and fas/fasL independent and occurred via apoptosis. It was not observed in LCMV-infected DNA fragmentation factor 45-deficient mice, and an increase in active caspase <em>3</em>-specific staining was found in liver NKT cells from LCMV-infected and poly(I-C)-treated mice compared to uninfected wild-type mice. Interestingly, it was also found that liver NKT cells from LCMV-infected mice were themselves infected. These results suggest that the loss of NKT cells following an acute LCMV infection could be due to the induction of IFN-<em>alpha</em>/beta resulting in NKT-cell apoptosis and is important for the host's immune response to LCMV.

Early studies of patients dying from status asthmaticus revealed marked inflammation of the bronchial tree. Subsequent histological studies of the airways and examination of bronchoalveolar lavage fluid of subjects with mild asthma have confirmed the presence of airway inflammation in life. There is epithelial edema and desquamation, subepithelial deposition of collagen and fibronectin, and an inflammatory cell infiltrate in the mucosa. There are increased numbers of activated eosinophils, CD25-positive T lymphocytes, and immature macrophages with the phenotypic characteristics of blood monocytes. An increased expression of HLA class II is present on epithelium, macrophages, and other infiltrating cells. The severity of clinical asthma correlates with several measurements of the severity of the inflammatory response, suggesting a crucial role for airway inflammation in the pathophysiology of the disease. There is considerable interest and research into the mechanisms underlying the pathogenesis and maintenance of the inflammatory response in asthma. The development and maintenance of the inflammatory response in asthma is likely to be a consequence of a complicated interaction between various cells and the mediators they generate. The characterization of an ever-increasing number of cytokines is of particular interest. Interleukin-<em>3</em>, interleukin-5, and granulocyte-macrophage colony-stimulating factor are hematopoietic growth factors that increase the survival of eosinophils in culture and enhance certain eosinophil functions, such as mediator generation and toxicity. Alveolar macrophages derived from asthmatic subjects produce twofold to threefold more GM-CSF than do those from normal control subjects. Using in situ hybridization, the presence of IL-5 mRNA has been demonstrated in bronchial biopsies from asthmatic subjects. Thus IL-<em>3</em>, IL-5, and GM-CSF influence eosinophil function and survival, and may be generated by T lymphocytes and/or alveolar macrophages within the airways in asthma. In addition to these three cytokines, IL-4 and <em>interferon</em>-gamma may be crucial to the regulation of IgE biosynthesis. TNF-<em>alpha</em> and IL-1 are potentially important in the up-regulation of endothelial adhesion molecules. An important step in the recruitment of leukocytes to an inflammatory focus is margination to the vascular endothelium. Our understanding of the molecular events involved in migration of leukocytes to an inflammatory focus has been advanced by the discovery and characterization of a variety of cell adhesion molecules. The potential role of ELAM-1 and ICAM-1 in allergic inflammation is suggested by their up-regulation on vascular endothelium in association with late cutaneous responses to allergen and by their role in certain primate models of asthma.(ABSTRACT TRUNCATED AT 400 WORDS)

BACKGROUND

The authors reported previously the beneficial effects of interferon (IFN)-alpha/5-fluorouracil (5-FU) combination therapy for patients with advanced hepatocellular carcinoma (HCC) who have tumor thrombi in the major portal branches. In this report, the authors describe the results from IFN/5-FU chemotherapy for patients who underwent palliative hepatic resection for advanced HCC with tumor thrombus in the main trunk of the portal vein and multiple nodules in the whole liver. In addition, they evaluated the correlation between the response to such therapy and expression of IFN-alpha type 2 receptor (IFNAR2).

METHODS

From October 1999 to December 2004, 30 patients with advanced HCC, tumor thrombi in the main trunk of the portal vein, and multiple nodules in the whole liver (Vp4 and grade 3 intrahepatic metastases) were recruited for this study. They underwent palliative hepatic resection followed by at least 2 courses of IFN/5-FU. IFNAR2 expression levels were determined by immunohistochemistry.

RESULTS

No major treatment-related complications were noted. An objective response was noted in 10 patients (33.3%) and included a complete response in 6 patients (20%), a partial response in 4 patients (13.3%), no response in 1 patient (3.3%), and progressive disease in 19 patients (63.4%). IFNAR2 expression was detected in 20 of 30 patients (66.7%). There was a significant difference in overall survival between patients with positive and negative IFNAR2 expression cases (P<.0025), and a significant correlation was observed between IFNAR2 expression and response to IFN/5-FU combination therapy (P=.0199).

CONCLUSIONS

Adjunct IFN/5-FU therapy is a promising modality for patients with advanced HCC, tumor thrombi in the major trunk, and multiple nodules after palliative hepatic resection. The results from this study indicated that the response to such therapy seemed to be correlated with IFNAR2 expression.

Activation of host cell antiviral responses is mediated by receptors detecting the presence of viruses. Here we have studied the role of double-stranded RNA (dsRNA) binding molecules melanoma differentiation-associated gene 5 (mda-5), retinoic acid inducible gene I (RIG-I), and Toll-like receptor <em>3</em> (TLR<em>3</em>) in measles virus (MV)-induced expression of antiviral cytokines and chemokines in human A549 lung epithelial cells and human umbilical vein endothelial cells (HUVECs). We show that MV infection results in the activation of mda-5, RIG-I, and TLR<em>3</em> gene expression that is followed by high expression of <em>interferon</em> (IFN)-beta, interleukin (IL)-28 and IL-29, CCL5, and CXCL10 genes. We also demonstrate that IFN-<em>alpha</em> and IFN-beta upregulate mda-5, RIG-I, and TLR<em>3</em> gene expression in epithelial and endothelial cell lines. Forced expression of mda-5, but not that of RIG-I or TLR<em>3</em>, leads to enhanced IFN-beta promoter activity in MV-infected A549 cells. Our results suggest that IFN-inducible mda-5 is involved in MV-induced expression of antiviral cytokines.

We have described earlier a gene cluster, including at least six <em>interferon</em>-activatable genes closely linked to the erythroid <em>alpha</em> spectrin locus and the serum amyloid P-component locus on murine chromosome 1. Here, we report that sequences of three genes from the cluster (the 201, 202, and 204 genes) are very similar in a segment extending from at least 550 nucleotides upstream of the <em>3</em>' end of the transcription initiation region to beyond the first exon intron border (96% similarity between the 202 and 204 genes and 89% similarity between the 201 and 204 genes). This region contains the following two types of <em>interferon</em>-responsive enhancers: a GA box and a Friedman Stark sequence. The proteins coded for by the 202 gene (51 kDa) and the 204 gene (72 kDa) are hydrophilic. The amino acids have been conserved in the two proteins in 47% of the sequence. Each protein includes two apparently contiguous, approximately 200-amino acid long segments with much sequence similarity (27% in the 202 protein and <em>3</em>4% in the 204 protein). These segments are preceded in the 204 protein only by a segment including four perfect and three imperfect repeats of a 7 amino acid sequence. These and other data suggest that the evolution of the gene cluster involved the duplication of a DNA segment generating a double length transcription unit and subsequent divergence and duplication of this unit giving rise to at least two <em>interferon</em>-activatable genes (the 202 and 204 genes).

We have examined the sequence elements and corresponding DNA-binding factors required for transient expression of the A <em>alpha</em> d promoter fused to the bacterial chloramphenicol acetyltransferase reporter gene in a variety of cultured cell lines. Deletion analysis demonstrated that only about 110 nucleotides of sequence 5' of the transcription start site are required for constitutive expression in the murine B-lymphoma cell line A20 or for gamma <em>interferon</em>-induced expression in the murine monocytic cell line WEHI-<em>3</em>. Linker-scanner mutation of this region indicated that at least three sequence elements are required for promoter activity. These elements correspond to the conserved sequence elements found in other human and mouse class II genes, the X box, the Y box, and the H box. Analysis of DNA-binding activity showed that the three most predominant factors present in extracts from WEHI-<em>3</em>, A20, or L cells (which do not express the class II genes) are actually a family of factors that bind to a fourth sequence element, overlapping the <em>3</em>' end of the X-box sequence, that is homologous to the cyclic AMP-responsive enhancer element. A single common factor that binds to the Y box was detected in extracts from all cells tested, as has been seen with the Y-box elements of other class II genes. Another common factor was found that binds to the more conserved 5' region of the X-box element, although A20 extracts contained a second, distinct binding activity for this region. A common binding factor for the H-box element was detected in extracts from WEHI-<em>3</em> and L cells. However, this activity was absent in A20 cell extracts. Instead, two different H-box-binding activities were detected, suggesting that different components are involved in class II gene expression in B cells and macrophages. Finally, gamma <em>interferon</em> treatment did not significantly alter the DNA-binding activity in WEHI-<em>3</em> cells for any of the sequence elements shown to be required for induced chloramphenicol acetyltransferase expression.

The influence of endogenous interleukin (IL)-12 on the course of pulmonary histoplasmosis was examined in naive and immune mice. All naive animals pretreated with anti-IL-12 monoclonal antibody (MAb) died by day 14. All mice died when anti-IL-12 MAb was initiated as late as postinfection day <em>3</em>. Unlike those of controls, lungs of naive mice given anti-IL-12 MAb had depressed levels of <em>interferon</em> (IFN)-gamma and increased tumor necrosis factor (TNF)-<em>alpha</em>. The 2 groups had similar IL-4 levels. Administration of anti-IL-4 MAb rescued mice from the inimical effects of anti-IL-12 MAb. Survival of mice given both anti-IL-12 and anti-IL-4 MAb was associated with a blunted TNF-<em>alpha</em> response. In reinfection histoplasmosis, treatment with anti-IL-12 MAb did not alter survival. Fungus burden in lungs, livers, and spleens differed at week 2, but not at week 1, of infection. Thus, endogenous IL-12 is critical for optimal generation of a protective immune response in pulmonary histoplasmosis.

OBJECTIVE

An intertwined cascading network of cytokines is believed to direct the development of endotoxin-induced uveitis (EIU). This study investigated mRNA levels of interleukin (IL) 1 alpha, IL-1 beta, IL-6, tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, transforming growth factor (TGF)-beta 1, and the helper T lymphocyte marker, CD4, during the course of EIU in rats.

METHODS

Reverse transcription followed by polymerase chain reaction amplification was used to determine relative mRNA levels in four ocular tissues (iris/ciliary body, cornea, lens, and neuroretina) at 0, 1, 3, 6, 24, and 48 hours after subcutaneous injection of 200 micrograms of Escherichia coli endotoxin.

RESULTS

Four general patterns of mRNA expression were observed: (1) constitutively expressed and unaffected by endotoxin; (2) constitutively expressed but further induced by endotoxin, reaching peak levels at 3 hours postinjection; (3) initially undetectable or marginally detectable and induced by endotoxin, with peak levels occurring 3 hours postinjection; and (4) never present at appreciable levels. The most dramatic responses were seen in the mRNA levels of IL-1 alpha, IL-1 beta, IL-6, TNF-alpha, and IFN-gamma in iris/ciliary body. Lesser mRNA level responses were found for IL-1 beta and IL-6 in cornea and for IL-1 alpha, IL-1 beta, IL-6, TNF-alpha, and IFN-gamma in neuroretina. Little or no changes in mRNA levels were observed for CD4 or TGF-beta 1 in any tissue or for any mRNA examined in lens.

CONCLUSIONS

These data show that subcutaneous endotoxin induces cytokine mRNA expression differentially in ocular tissues. These data support the hypothesis that induction of cytokine expression in iris/ciliary body plays a major role in the development of EIU.

In a group of <em>3</em>0 human tumors, comprising 12 lung, 14 ovarian, 2 breast carcinomas, 1 hypernephroma and 1 mid-gut carcinoid, the expression of major histocompatibility complex (MHC) class I molecules and the intercellular adhesion molecule 1 (CAM-1, CD54) was found to vary independently. Some tumors expressed both or neither of these molecules. Among 9/1<em>3</em> ICAM-1+ tumors, in which greater than 50% cells reacted with the anti-ICAM-1 monoclonal antibody (mAb) (LB-2), the class I antigen was also detected on greater than 50% of the cells. Only 2 ICAM-1+ tumors were class-I-. In 5/17 cases the tumors were MHC-class-I+ and ICAM-1-. Lymphocytes collected from the blood or from the tumor site were assayed for recognition on the tumor cells in the auto-tumor cytotoxicity test and in mixed lymphocyte tumor cell culture (MLTC). Positive results were obtained only with the MHC-class-I+/ICAM-1+ tumors. In vitro treatment of the tumor cell suspensions with <em>interferon</em> gamma and tumor necrosis factor <em>alpha</em> (TNF <em>alpha</em>) induced or enhanced the ICAM-1 and/or class I antigen expression in 8/12 cases. Of the tumor samples treatged, 8/9 acquired stimulatory capacity and <em>3</em>/10 became susceptible to lysis by the lymphocytes. In 6/6 MLTC performed with the cytokine-treated tumor cells, cytotoxicity against the autologous tumor was generated. Three of these MLTC lymphocytes also lysed the untreated targets. mAb directed to class I antigens or to ICAM-1 inhibited both the stimulation by and the lysis of tumor cells when confronted with fresh lymphocytes. The cytotoxicity generated in the MLTC was also inhibited. If, however, the cytotoxic function was induced in MTLC containing interleukin-2 (5 U/ml), inhibition was obtained only by pretreatment of the targets with mAb against ICAM-1. The results show thus (a) that the lymphocytes react in vitro with tumor cells only if these express both MHC class I molecules and ICAM-1; (b) that expression of these molecules can be induced by <em>interferon</em> <em>alpha</em> and TNF <em>alpha</em>; (c) that cytotoxic effectors generated in the MLTC with cytokine-treated tumors can also act on the untreated tumor cells. The requirement of the two surface moieties for the interaction with lymphocytes was also substantiated by blockade with relevant mAb.

Endothelium-derived nitric oxide (NO) causes vasodilatation by activating soluble guanylate cyclase, and glomerular mesangial cells respond to NO with elevations of intracellular guanosine <em>3</em>',5'-cyclic monophosphate (cGMP). We explored whether mesangial cells can be stimulated to produce NO and whether NO modulates mesangial cell function in an autocrine or paracrine fashion. Tumor necrosis factor <em>alpha</em> (TNF-<em>alpha</em>) raised mesangial cell cGMP levels in a time- and concentration-dependent manner (threshold dose 1 ng/ml, IC50 1<em>3</em>.8 ng/ml, maximal response 100 ng/ml). TNF-<em>alpha</em>-induced increases in mesangial cGMP content were evident at 8 h and maximal at 18-24 h. The TNF-<em>alpha</em>-induced stimulation of mesangial cell cGMP production was abrogated by actinomycin D or cycloheximide suggesting dependence on new RNA or protein synthesis. Hemoglobin and methylene blue, both known to inhibit NO action, dramatically reduced TNF-<em>alpha</em>-induced mesangial cell cGMP production. Superoxide dismutase, known to potentiate NO action, augmented the TNF-<em>alpha</em>-induced effect. Ng-monomethyl-L-arginine (L-NMMA) decreased cGMP levels in TNF-<em>alpha</em>-treated, but not vehicle-treated mesangial cells in a concentration-dependent manner (IC50 5<em>3</em> microM). L-arginine had no effect on cGMP levels in control or TNF-<em>alpha</em>-treated mesangial cells but reversed L-NMMA-induced inhibition. Interleukin 1 beta and lipopolysaccharide (LPS), but not <em>interferon</em> gamma, also increased mesangial cell cGMP content. Transforming growth factor beta 1 blunted the mesangial cell response to TNF-<em>alpha</em>. TNF-<em>alpha</em>-induced L-arginine-dependent increases in cGMP were also evident in bovine renal artery vascular smooth muscle cells, COS-1 cells, and 1502 human fibroblasts. These findings suggest that TNF-<em>alpha</em> induces expression in mesangial cell of an enzyme(s) involved in the formation of L-arginine-derived NO. Moreover, the data indicate that NO acts in an autocrine and paracrine fashion to activate mesangial cell soluble guanylate cyclase. Cytokine-induced formation of NO in mesangial and vascular smooth muscle cells may be implicated in the pathogenesis of septic shock.

OBJECTIVE

To evaluate treatment outcome of acute hepatitis C virus (HCV) in HIV-positive individuals.

METHODS

Open-label, prospective study conducted in London, January 1997-December 2003.

METHODS

Patients in whom acute HCV infection had been diagnosed had sequential HCV RNA levels measured at 0, 4, 12, 24, 32, and 48 weeks. If HCV RNA positive at 12 weeks, patients were offered pegylated interferon alpha-2b 1.5 microg/kg/wk and ribavirin 800-1200 mg/d for 24 weeks. Patients with increasing HCV RNA titers were offered treatment earlier.

RESULTS

Fifty male homosexuals with a mean age 37 years were identified: 44 from abnormal liver function test results, 4 from sexual contact with an HCV-positive partner, and 2 at HIV seroconversion. Overall, 12 individuals became HCV RNA negative spontaneously. This was significantly associated with high baseline median CD4(+) count (P = 0.029), CD4(+) count >500 cells/mm(3) (P = 0.017), and lower HCV RNA titers (P = 0.017). Only 27 patients accepted treatment, 16 (59%) of whom reached sustained virologic response. This was associated with higher peak mean alanine aminotransferase (P < 0.001) and higher baseline CD4% (P = 0.041).

CONCLUSIONS

Sustained virologic response rates in HIV-positive patients treated for acute HCV infection are lower than in HIV-negative subjects. Because a high percentage of individuals seroconvert spontaneously, treatment should be delayed until after 12 weeks.

BACKGROUND

Interferon alpha is the only agent approved for the postoperative adjuvant treatment of high-risk cutaneous melanoma. However, the survival advantage associated with this treatment is unclear, especially in terms of overall survival. Thus, adjuvant interferon is not universally considered a gold standard treatment by all oncologists.

OBJECTIVE

To assess the disease-free survival and overall survival effects of interferon alpha as adjuvant treatment for people with high-risk cutaneous melanoma.

METHODS

We searched the following databases up to August 2012: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2012, issue 8), MEDLINE (from 2005), EMBASE (from 2010), AMED (from 1985), and LILACS (from 1982). We also searched trials databases in 2011, and proceedings of the ASCO annual meeting from 2000 to 2011. We checked the reference lists of selected articles for further references to relevant trials.

METHODS

We included only randomised controlled trials (RCTs) comparing interferon alpha to observation (or any other treatment) for the postoperative (adjuvant) treatment of patients with high-risk skin melanoma, that is, people with regional lymph node metastasis (American Joint Committee on Cancer (AJCC) TNM (tumour, lymph node, metastasis) stage III) undergoing radical lymph node dissection, or people without nodal disease but with primary tumour thickness greater than 1 mm (AJCC TNM stage II).

METHODS

Two authors extracted data, and a third author independently verified the extracted data. The main outcome measure was the hazard ratio (HR), which is the ratio of the risk of the event occurring in the treatment arm (adjuvant interferon) compared to the control arm (no adjuvant interferon). The survival data were either entered directly into Review Manager (RevMan) or extrapolated from Kaplan-Meier plots and then entered into RevMan. Based on the presence of between-study heterogeneity, we applied a fixed-effect or random-effects model for calculating the pooled estimates of treatment efficacy.

RESULTS

Eighteen RCTs enrolling a total of 10,499 participants were eligible for the review. The results from 17 of 18 of these RCTs, published between 1995 and 2011, were suitable for meta-analysis and allowed us to quantify the therapeutic efficacy of interferon in terms of disease-free survival (17 trials) and overall survival (15 trials). Adjuvant interferon was associated with significantly improved disease-free survival (HR (hazard ratio) = 0.83; 95% CI (confidence interval) 0.78 to 0.87, P value < 0.00001) and overall survival (HR = 0.91; 95% CI 0.85 to 0.97; P value = 0.003). We detected no significant between-study heterogeneity (disease-free survival: I² statistic = 16%, Q-test P value = 0.27; overall survival: I² statistic = 6%; Q-test P value = 0.38).Considering that the 5-year overall survival rate for TNM stage II-III cutaneous melanoma is 60%, the number needed to treat (NNT) is 35 participants (95% CI = 21 to 108 participants) in order to prevent 1 death. The results of subgroup analysis failed to answer the question of whether some treatment features (i.e. dosage, duration) might have an impact on interferon efficacy or whether some participant subgroups (i.e. with or without lymph node positivity) might benefit differently from interferon adjuvant treatment.Grade 3 and 4 toxicity was observed in a minority of participants: In some trials, no-one had fever or fatigue of Grade 3 severity, but in other trials, up to 8% had fever and up to 23% had fatigue of Grade 3 severity. Less than 1% of participants had fever and fatigue of Grade 4 severity. Although it impaired quality of life, toxicity disappeared after treatment discontinuation.

CONCLUSIONS

The results of this meta-analysis support the therapeutic efficacy of adjuvant interferon alpha for the treatment of people with high-risk (AJCC TNM stage II-III) cutaneous melanoma in terms of both disease-free survival and, though to a lower extent, overall survival. Interferon is also valid as a reference treatment in RCTs investigating new therapeutic agents for the adjuvant treatment of this participant population. Further investigation is required to select people who are most likely to benefit from this treatment.

Hepatitis C virus (HCV) infection recurs in liver recipients who are viremic at transplantation. We conducted a randomized, controlled trial to test the efficacy and safety of pretransplant pegylated <em>interferon</em> <em>alpha</em>-2b plus ribavirin (Peg-IFN-α2b/RBV) for prevention of post-transplant HCV recurrence. Enrollees had HCV and were listed for liver transplantation, with either potential living donors or Model for End-Stage Liver Disease upgrade for hepatocellular carcinoma. Patients with HCV genotypes (G) 1/4/6 (n = 44/2/1) were randomized 2:1 to treatment (n = <em>3</em>1) or untreated control (n = 16); HCV G2/<em>3</em> (n=<em>3</em>2) were assigned to treatment. Overall, 59 were treated and 20 were not. Peg-IFN-α2b, starting at 0.75 μg/kg/week, and RBV, starting at 600 mg/day, were escalated as tolerated. Patients assigned to treatment versus control had similar baseline characteristics. Combined virologic response (CVR) included pretransplant sustained virologic response and post-transplant virologic response (pTVR), defined as undetectable HCV RNA 12 weeks after end of treatment or transplant, respectively. In intent-to-treat analyses, 12 (19%) assigned to treatment and 1 (6%) assigned to control achieved CVR (P = 0.29); per-protocol values were 1<em>3</em> (22%) and 0 (0%) (P = 0.0<em>3</em>). Among treated G1/4/6 patients, 2<em>3</em> of <em>3</em>0 received transplant, of whom 22% had pTVR; among treated G2/<em>3</em> patients 21 of 29 received transplant, of whom 29% had pTVR. pTVR was 0%, 18%, and 50% in patients treated for <8, 8-16, and >16 weeks, respectively (P = 0.01). Serious adverse events (SAEs) occurred with similar frequency in treated versus untreated patients (68% versus 55%; P = 0.<em>3</em>0), but the number of SAEs per patient was higher in the treated group (2.7 versus 1.<em>3</em>; P = 0.00<em>3</em>).

CONCLUSIONS

Pretransplant treatment with Peg-IFN-α2b/RBV prevents post-transplant recurrence of HCV in selected patients. Efficacy is higher with >16 weeks of treatment, but treatment is associated with increased risk of potentially serious complications.

The complement protein C4 is a non-enzymatic component of the C<em>3</em> and C5 convertases and thus essential for the propagation of the classical complement pathway. The covalent binding of C4 to immunoglobulins and immune complexes (IC) also enhances the solubilization of immune aggregates, and the clearance of IC through complement receptor one (CR1) on erythrocytes. Human C4 is the most polymorphic protein of the complement system. In this review, we summarize the current concepts on the 1-2-<em>3</em> loci model of C4A and C4B genes in the population, factors affecting the expression levels of C4 transcripts and proteins, and the structural, functional and serological diversities of the C4A and C4B proteins. The diversities and polymorphisms of the mouse homologues Slp and C4 proteins are described and contrasted with their human homologues. The human C4 genes are located in the MHC class III region on chromosome 6. Each human C4 gene consists of 41 exons coding for a 5.4-kb transcript. The long gene is 20.6 kb and the short gene is 14.2 kb. In the Caucasian population 55% of the MHC haplotypes have the 2-locus, C4A-C4B configurations and 45% have an unequal number of C4A and C4B genes. Moreover, three-quarters of C4 genes harbor the 6.4 kb endogenous retrovirus HERV-K(C4) in the intron 9 of the long genes. Duplication of a C4 gene always concurs with its adjacent genes RP, CYP21 and TNX, which together form a genetic unit termed an RCCX module. Monomodular, bimodular and trimodular RCCX structures with 1, 2 and <em>3</em> complement C4 genes have frequencies of 17%, 69% and 14%, respectively. Partial deficiencies of C4A and C4B, primarily due to the presence of monomodular haplotypes and homo-expression of C4A proteins from bimodular structures, have a combined frequency of <em>3</em>1.6%. Multiple structural isoforms of each C4A and C4B allotype exist in the circulation because of the imperfect and incomplete proteolytic processing of the precursor protein to form the beta-<em>alpha</em>-gamma structures. Immunofixation experiments of C4A and C4B demonstrate>> 41 allotypes in the two classes of proteins. A compilation of polymorphic sites from limited C4 sequences revealed the presence of 24 polymophic residues, mostly clustered C-terminal to the thioester bond within the C4d region of the <em>alpha</em>-chain. The covalent binding affinities of the thioester carbonyl group of C4A and C4B appear to be modulated by four isotypic residues at positions 1101, 1102, 1105 and 1106. Site directed mutagenesis experiments revealed that D1106 is responsible for the effective binding of C4A to form amide bonds with immune aggregates or protein antigens, and H1106 of C4B catalyzes the transacylation of the thioester carbonyl group to form ester bonds with carbohydrate antigens. The expression of C4 is inducible or enhanced by gamma-<em>interferon</em>. The liver is the main organ that synthesizes and secretes C4A and C4B to the circulation but there are many extra-hepatic sites producing moderate quantities of C4 for local defense. The plasma protein levels of C4A and C4B are mainly determined by the corresponding gene dosage. However, C4B proteins encoded by monomodular short genes may have relatively higher concentrations than those from long C4A genes. The 5' regulatory sequence of a C4 gene contains a Spl site, three E-boxes but no TATA box. The sequences beyond--1524 nt may be completely different as the C4 genes at RCCX module I have RPI-specific sequences, while those at Modules II, III and IV have TNXA-specific sequences. The remarkable genetic diversity of human C4A and C4B probably promotes the exchange of genetic information to create and maintain the quantitative and qualitative variations of C4A and C4B proteins in the population, as driven by the selection pressure against a great variety of microbes. An undesirable accompanying byproduct of this phenomenon is the inherent deleterious recombinations among the RCCX constituents leading to autoimmune and genetic disorders.

Middle East respiratory syndrome coronavirus (MERS-CoV) is a novel and highly pathogenic human coronavirus and has quickly spread to other countries in the Middle East, Europe, North Africa and Asia since 2012. Previous studies have shown that MERS-CoV ORF4b antagonizes the early antiviral <em>alpha</em>/beta <em>interferon</em> (IFN-α/β) response, which may significantly contribute to MERS-CoV pathogenesis; however, the underlying mechanism is poorly understood. Here, we found that ORF4b in the cytoplasm could specifically bind to TANK binding kinase 1 (TBK1) and IκB kinase epsilon (IKKε), suppress the molecular interaction between mitochondrial antiviral signaling protein (MAVS) and IKKε, and inhibit IFN regulatory factor <em>3</em> (IRF<em>3</em>) phosphorylation and subsequent IFN-β production. Further analysis showed that ORF4b could also inhibit IRF<em>3</em> and IRF7-induced production of IFN-β, whereas deletion of the nuclear localization signal of ORF4b abrogated its ability to inhibit IRF<em>3</em> and IRF7-induced production of IFN-β, but not IFN-β production induced by RIG-I, MDA5, MAVS, IKKε, and TBK-1, suggesting that ORF4b could inhibit the induction of IFN-β in both the cytoplasm and nucleus. Collectively, these results indicate that MERS-CoV ORF4b inhibits the induction of type I IFN through a direct interaction with IKKε/TBK1 in the cytoplasm, and also in the nucleus with unknown mechanism. Viruses have evolved multiple strategies to evade or thwart a host's antiviral responses. A novel human coronavirus (HCoV), Middle East respiratory syndrome coronavirus (MERS-CoV), is distinguished from other coronaviruses by its high pathogenicity and mortality. However, virulence determinants that distinguish MERS-CoV from other HCoVs have yet to be identified. MERS-CoV ORF4b antagonizes the early antiviral response, which may contribute to MERS-CoV pathogenesis. Here, we report the identification of the <em>interferon</em> (IFN) antagonism mechanism of MERS-CoV ORF4b. MERS-CoV ORF4b inhibits the production of type I IFN through a direct interaction with IKKε/TBK1 in the cytoplasm, and also in the nucleus with unknown mechanism. These findings provide a rationale for the novel pathogenesis of MERS-CoV as well as a basis for developing a candidate therapeutic against this virus.