Effects of interferon-alpha subtypes on the TH1/TH2 balance in peripheral blood mononuclear cells from patients with hepatitis virus infection-associated liver disorders

Pathogenesis of Paradoxical Reactions Associated with Targeted Biologic Agents for Inflammatory Skin Diseases

Targeted biologic agents have dramatically changed the therapeutic landscape for immune-mediated inflammatory diseases, particularly in rheumatology and dermatology. Their introduction has resulted in a paradigm shift, i.e., they produce significant clinical improvements in most patients with such diseases. Nevertheless, a variety of adverse reactions associated with these agents have been observed, including so-called paradoxical reactions (PRs), which are a new class of adverse events. PRs involve the de novo development or worsening of immune-mediated inflammatory disease during treatment with a targeted biologic agent that is commonly used to treat the idiopathic counterpart of the drug-induced reaction. In addition, the efficacy of biologic agents targeting individual cytokines and the existence of PRs to them have provided proof that cytokines are key drivers of various immune-mediated inflammatory diseases and helped researchers elucidate the molecular pathways underlying the pathophysiology of these diseases. Here, a comprehensive review of the targeted biologic agents used to treat immune-mediated inflammatory diseases, particularly psoriasis and atopic dermatitis, is provided, with a specific focus on biologic agents that inhibit cytokine signaling involving tumor necrosis factor-α, interleukin (IL)-12/23 (p40), IL-17A (and the IL-17 receptor [R]), IL-23 (p19), and the IL-4Rα, and their associated PRs. The characteristic clinical manifestations and potential immunological mechanisms of the PRs induced by these biologic agents are also reviewed.

Eczematous Drug Eruptions

Eczematous drug eruptions are a heterogenous group of skin reactions that resemble eczema both clinically and histologically. We reviewed the literature and cataloged the systemically administered medications that cause these eruptions, along with their characteristic clinical presentations. We identified three primary pathophysiologic etiologies: (1) cutaneous immunomodulation, (2) skin dehydration, and (3) delayed hypersensitivity. Notably, eczematous eruptions caused by altered immunity in the skin may be increasing in incidence as some responsible drugs, in particular biologic therapies (such as tumor necrosis factor-α and interleukin-17 inhibitors) and targeted cancer treatments (including immune checkpoint inhibitors and epidermal growth factor receptor inhibitors), become more commonly employed in clinical practice. Other notable causes of eczematous eruptions include antiviral agents for hepatitis C virus and cardiovascular medications in elderly individuals, and notable subtypes of eczematous reactions include systemic contact dermatitis and photoallergic reactions, which are also discussed. The diagnostic gold standard is drug rechallenge and most reactions may be treated effectively with emollients, topical corticosteroids, and oral antihistamines.

Phenotypic switch to eczema in patients receiving biologics for plaque psoriasis: a systematic review

The use of biologic therapies for the treatment of chronic plaque psoriasis has been linked to the development of atopic eczema, amongst other cutaneous adverse events. This can cause diagnostic confusion and create difficulty in the management of patients with plaque psoriasis. The main objective of this systematic review was to review all cases of eczema, including atopic eczema, reported in patients treated with biologics for chronic plaque psoriasis. PubMed, Medline and Embase databases were used to identify studies reporting eczema in patients treated with biologic therapy for chronic plaque psoriasis. A total of 92 patients were identified from 24 studies, with patients treated with either: adalimumab; etanercept; infliximab; ixekizumab; secukinumab; or ustekinumab. Factors common to some reported cases include: a prior history of atopy; eosinophilia; raised serum immunoglobulin E. Twenty-three had documented treatment outcomes; 14 had biologic therapy discontinued or switched. Management strategies included topical or oral corticosteroids, and treatment with alternative systemic agents such as ciclosporin or apremilast. This adverse event occurred in 1.0-12.1% of patients within trial data and observational studies. This review demonstrates that there are consistent reports of a switch to an atopic eczema phenotype from psoriasis in patients taking biologics inhibiting tumour necrosis factor alpha and the interleukin (IL)-17/IL-23 axis. The majority stopped the implicated biologic, but conservative management was successful in some cases. Those with an atopic diathesis may be more at risk. Elucidation of mechanisms and risk factors would contribute to optimal therapy selection for individual patients.

Studies to analyse the relationship between IFNα2b gene dosage and its expression, using a Pichia pastoris-based expression system

Human interferon α2b (hIFNα2b) is the most important member of the interferon family. Escherichia coli, yeasts, mammalian cell cultures and baculovirus-infected insect cells have been used for expressing recombinant human interferon. Recently a Pichia pastoris-based expression system has emerged as an attractive system for producing functional human recombinant IFNα2b. In this regard, gene dosage is considered an important factor in obtaining the optimum expression of recombinant protein, which may vary from one protein to another. In the present study we have shown the effect of IFNα2b gene dosage on extracellular expression of IFNα2b recombinant protein from P. pastoris. Constructs containing from one to five repeats of IFNα2b-expressing cassettes were created via an in vitro multimerization approach. P. pastoris host strain X-33 was transformed using these expression cassettes. Groups of P. pastoris clones transformed with different copies of the IFNα2b expression cassette were screened for intrachromosomal integration. The IFNα2b expression level of stable transformants was checked. The copy number of integrated IFNα2b was determined by performing qPCR of genomic DNA of recombinant P. patoris clones. It was observed that an increase in copy number generally had a positive effect on the expression level of IFNα2b protein. Regarding the performance of multicopy strains, those obtained from transformation of multicopy vectors showed relatively high expression, compared to those generated using transformation vector having only one copy of IFNα2b. It was also observed that an increase in drug resistance of a clone did not guarantee its high expression, as integration of a marker gene did not always correlate with integration of the gene of interest.

Changes in the balance between Treg and Th17 cells in patients with chronic hepatitis B

The purpose of this study was to explore the role of Treg cells, Th17 cells and cytokines associated with Treg/Th17 differentiation in the occurrence, development and outcome of chronic hepatitis B (CHB). To do so, we detected populations of Treg and Th17 cells and their associated cytokines in the peripheral blood of CHB patients. The populations of Treg cells (CD4(+)CD25(high)CD127(low) T cells) and Th17 cells (CD3(+)CD8(-)IL-17(+) T cells) were analyzed in 46 patients with low to moderate chronic hepatitis B (CHB-LM), 24 patients with severe chronic hepatitis B (CHB-S) and 20 healthy controls (HC) using flow cytometry. The levels of cytokines associated with Treg/Th17 differentiation, including IL-10, TGF-β1, IL-17 and IL-23, were measured by enzyme-linked immunosorbent assay (ELISA). Our study showed that the imbalance of Treg and Th17 cells might play an important role in the occurrence, development and outcome of CHB.

Is T-helper type 2 shift schizophrenia-specific? Primary results from a comparison of related psychiatric disorders and healthy controls

AIM

An imbalance between T-helper type 1 (Th1) and type 2 (Th2) cytokines has been implicated in schizophrenia, although empirical evidence is rare. The aim of this study was to examine if a Th1/Th2 imbalance occurs in schizophrenia and schizophrenia-related disorder.

METHODS

Twenty-six subjects with schizophrenia, 26 subjects with schizophrenia-related disorders, and 26 healthy controls were recruited. The Human Th1/Th2 Cytokine Cytometric Bead Array Kit-II was utilized to assess serum Th1/Th2 cytokines and ratios simultaneously. MANOVA was used to detect differences among the three diagnostic groups in distinct Th1/Th2 cytokines/ratios. Pearson/Spearman correlations were used to examine the relationships between distinct Th1/Th2 cytokines/ratios and clinical/psychopathological data in schizophrenia.

RESULTS

Interferon (IFN)-γ/interleukin (IL)-4, IFN-γ/IL-10, IL-2/IL-4, and tumor necrosis factor (TNF)-α/IL-4 ratios were significantly decreased in schizophrenia, but not in schizophrenia-related disorders compared to healthy controls. IFN-γ/IL-4 and IFN-γ/IL-10 in schizophrenia subjects positively correlated with age, but not in schizophrenia-related disorder subjects or in healthy controls.

CONCLUSION

A clear Th2 shift was observed in schizophrenia, but not in schizophrenia-related disorders. The Th2 shift in schizophrenia appeared to be an aberrant developmental phenomenon.

Effect of antiviral treatment with nucleoside and nucleotide analogues on cellular immune function in patients with chronic hepatitis B

China is a country where hepatitis B virus (HBV) infection is highly endemic, and a large sample survey shows that chronic HBV infection affects as many as 120 million people in China. Since immune response dysregulation caused by persistent HBV infection and replication is the underlying cause of disease progression in patients with chronic hepatitis B (CHB), effective antiviral therapy should be given to halt the progression of the disease. Nucleoside and nucleotide analogues have been generally accepted as effective anti-HBV drugs and widely used in the clinical setting. They exert antiviral effects against HBV mainly by inhibition of DNA polymerase-mediated DNA replication. In addition, nucleoside and nucleotide analogues also have an impact on the body's immune function. In this article we review recent progress in understanding the effect of antiviral treatment with nucleoside and nucleotide analogues on cellular immune function in CHB patients.

Reverse transcription real-time PCR for detection of porcine interferon α and β genes

A few studies provided convincing evidence of constitutive expression of type I interferons (IFNs) in humans and mice, and of the steady-state role of these cytokines under health conditions. These results were later confirmed in pigs, too. In line with this tenet, low levels of IFN-α/β can be detected in swine tissues in the absence of any specific inducer. These studies are compounded by the utmost complexity of type I IFNs (including among others 17 IFN-α genes in pigs), which demands proper research tools. This prompted us to analyse the available protocols and to develop a relevant, robust, reverse transcription (RT) real-time polymerase chain reaction (PCR) detection system for the amplification of porcine IFN-α/β genes. The adopted test procedure is user-friendly and provides the complete panel of gene expression of one subject in a microtitre plate. Also, a proper use of PCR fluorochromes (SYBR(®) versus EvaGreen(®) supermix) enables users to adopt proper test protocols in case of low-expression porcine IFN-α genes. This is accounted for by the much higher sensitivity of the test protocol with EvaGreen(®) supermix. Interestingly, IFN-β showed the highest frequency of constitutive expression, in agreement with its definition of 'immediate early' gene in both humans and mice. Results indicate that the outlined procedure can detect both constitutively expressed and virus-induced IFN-α/β genes, as well as the impact of environmental, non-infectious stressors on the previous profile of constitutive expression.

High-level expression of human interferon alpha-2b in transgenic carrot (Daucus carota L.) plants

In this study, we report the obtaining of carrot plants expressing human interferon alpha-2b via Agrobacterium-mediated transformation using two vector constructs containing the sequence coding for interferon gene fused with Nicotiana plumbagenifolia calreticulin apoplast targeting signal driven by 35S CaMV promoter and root-specific Mll promoter. The human interferon alpha-2b gene was correctly translated in carrot plants according to Western blot analysis. The recombinant protein exhibited antiviral activity in vitro by inhibition of vesicular stomatitis virus replication in established piglet testicular cells. The results demonstrated the higher activity of interferon accumulated in carrot plants for young leaves (up to 50.7 × 10(3) IU/g FW) compared to the mature ones probably due to the degradation-susceptible nature of this protein. The taproot-expressing system could have also provided the sufficient protein amounts (up to 16.5 × 10(3) IU/g FW) and could possibly be used for generating interferon alpha-2b protein in planta for preventing and curing infectious diseases.

Creation of interferon-alpha8 mutants with amino acid substitutions against interferon-alpha receptor-2 binding sites using phage display system and evaluation of their biologic properties

In this study, we describe the creation of three interferon-alpha (IFN-alpha)8 mutants with markedly higher antiviral and antiproliferative activities in comparison with those of the wild-type (wt)IFN-alpha8, wtIFN-alpha2, and IFN-con1 using a phage display system. Sequence analysis showed that three out of the six hot-spot amino acid residues of wtIFN-alpha8 known to be important for the interaction with the IFN-alpha receptor-2 (IFNAR-2)-binding sites were substituted to other amino acids and the others remained. Although affinity analysis revealed that the dissociation constant (K(D)) of IFN-alpha8 mutants was almost the same with that of wtIFN-alpha8, furthermore, the rates of association (k(a)) and dissociation (k(d)) were relatively lower. These results suggest that changes in the surface electronic charge of amino acid residues lead to changes in binding affinity and kinetics (prolonged dissociation time) toward the IFNAR-2, resulting in the modification of the biological activity. Moreover, our results demonstrate that the molecular engineering of the IFN-alpha8 provides important insight into action of IFN and also it would be useful in the development of therapeutically prominent IFN preparations than those used in clinical practice.

Rigid interferon-alpha subtype responses of human plasmacytoid dendritic cells

The large family of human type I interferon (IFN) includes 13 distinct subtypes of IFN-alpha, all utilizing a single type I IFN receptor. Many viruses have created evasion strategies to disable this cytokine family, highlighting their importance in antiviral defense. It is unclear what advantage the presence of so many different IFN-alpha subtypes provides, but functional differences observed among individual IFN-alpha subtypes suggested that they might play distinct regulatory roles during an immune response. To determine whether IFN-alpha subtype responses differ depending on a particular type of insult and thus whether IFN-alpha subtype responses are flexible to adapt to distinct pathogen challenges, we developed a novel nested multiplex reverse transcriptase polymerase chain reaction assay with which we measured expression of all IFN-alpha subtypes by freshly isolated human plasmacytoid dendritic cells (pDCs), a main source of IFN-alpha following pathogen challenge. Collectively our data show a remarkable stability in the relative magnitude and the kinetics of induction for each IFN-alpha subtype produced by pDC. Although various stimuli used, A-, B- and C-class CpGs, live and heat-inactivated influenza viruses and the TLR7 agonist R837 affected the overall magnitude of the response, each IFN-alpha subtype was induced at statistically similar relative levels and with similar kinetics, thereby revealing a great degree of rigidity in the IFN-alpha response pattern of pDC. These data are most consistent with the induction of optimized ratios of IFN-alpha subtypes, each of which may have differing signaling properties or alternatively, a great degree of redundancy in the IFN-alpha response.

Treatment with silybin-vitamin E-phospholipid complex in patients with hepatitis C infection

The aim of this study was to evaluate the hepatoprotective and anti-inflammatory effects of silybin-phospholipids and vitamin E complex (SPV complex), by determining cytokine patterns and various markers of liver disease. Forty Caucasian patients with chronic HCV infection were recruited and divided into two groups: 30 were treated with SPV complex for 3 months, while the other 10 did not receive any treatment. Ten other subjects without HCV infection but with staeatosic diagnosis were recruited and treated with SPV complex. Biochemical and hepatic principal parameters were investigated at 0 (T0) and 3 months (T3). The group of HCV patients treated showed an improvement trend of hepatic indecises and viral load, and had a significant and persistent reduction of ALT (P = 0.02) and AST serum level (P = 0.01). In this group cytokines showed a statistically significant increase of IL-2 (P = 0.03) and IL-6 were significantly reduced (P = 0.02) at T0 and T3. After the treatment the group of hepatic steatosics showed a significant decrease in ALT (P = 0.02), AST (0.008), gammaGT (0.004) alkaline phosphatase (0.05), total cholesterol (P = 0.03), fasting glucose (P = 0.008), insulinemia (0.0006), HOMA value (0.002) and C-reactive protein (CRP; 0.04). There was a significant reduction of IFN-gamma, TNF-alpha, and IL-6 (P = 0.02, 0.05 and 0.04, respectively). The data suggest that the SPV complex exerts hepatoprotective, anti-inflammatory and antifibrotic effects. This new compound may therefore be useful in clinical practice in patients with chronic hepatitis C who cannot undergo conventional antiviral therapy.

Genetic association of interferon-alpha subtypes 1, 2 and 5 in systemic lupus erythematosus

In this study, the association between the systemic lupus erythematosus (SLE) susceptibility and the new candidate genes, IFNA1, IFNA2 and IFNA5 genes, major interferon-alpha subtypes, in responses to viral infection was investigated. Allele and genotype frequencies of each marker were compared between 150 SLE patients and 150 healthy control subjects. This study indicated that the A/A genotype of IFNA5 (-2529) and the G/G genotype of IFNA1 (-1823) were associated with the protection of SLE disease in a recessive model [P(c) = 0.03, P = 0.01, odds ratio (OR) = 0.4, 95% confidence interval (CI) = 0.2-0.8 and P(c) = 0.09, P = 0.03, OR = 0.5, 95% CI = 0.2-0.9, respectively). Multifactor dimensionality reduction analysis showed a marginal interaction between IFNA5 (-2529) and IFNA1 (-1823) gene, with a cross-validation consistency of 10 of 10 and a prediction error of 46% (permutation P-value = 0.05). This is the first report of positive association of IFNA gene in SLE, especially the role of specific subtypes IFNA1 and IFNA5.

Type I IFN induced IL1-Ra expression in hepatocytes is mediated by activating STAT6 through the formation of STAT2: STAT6 heterodimer

The biological activities of type I interferons (IFNs) are mediated by their binding to a heterodimer receptor complex (IFNAR1 and IFNAR2), resulting in the activation of the JAK (JAK1 and TYK2)-STAT (1, 2, 3, 5 isotypes) signalling pathway. Although several studies have indicated that IFN-alpha and IFN-beta can activate complexes containing STAT6, the biological role of this activation is still unknown. We found that exposure of hepatoma cells (HuH7 and Hep3B) to IFN-alpha or IFN-beta led to the activation of STAT6. Activated STAT6 in turn induced the formation of STAT2: STAT6 complexes, which led to the secretion of IL-1Ra. The activation of STAT6 by type I IFN in hepatocytes was mediated by JAK1 and Tyk2. In addition, IFN-alpha or IFN-beta significantly enhanced the stimulatory effect of IL-1beta on production of IL-1Ra. The present study suggests a novel function of IFN-alpha and IFN-beta signalling in human hepatocytes. Our results provide evidence for the mechanism how IFN-alpha and IFN-beta modulate inflammatory responses through activation of STAT6 and production of secreted IL-1Ra.

Role of p53 in the inhibitory effects of interferon-alpha subtypes on proliferation of hepatocellular carcinoma cells

While interferon-alpha (IFN-alpha) subtypes share a common specific receptor composed of two subunits, interferon-alpha receptor (IFNAR)-1 and IFNAR-2, their subtype activities are exhibited via several intracellular signaling pathways and thus subsequently show different biological effects. Anti-proliferative effects of single treatment with IFN-alpha subtypes or 5-fluorouracil (FU), and of combined treatment with each IFN-alpha subtype and 5-FU were examined on three hepatocellular carcinoma cell lines, HepG2, HLE and PLC/PRF/5. HepG2 and PLC/PRF/5 cells were susceptible to the combination treatment, but HLE cells were not. Proliferation of PLC/PRF/5 cells was also inhibited by the IFN-alpha subtypes singly. In addition, apoptosis was observed in HepG2 cells upon treatment with 5-FU alone and with the combination treatment, and in PLC/PRF/5 cells after single treatment with the IFN-alpha subtypes and after the combination treatment. IFN-alpha subtypes induced cell cycle arrest in the G2/M phase in HepG2 and PLC/PRF/5. Analyses by Western blotting and immunoprecipitation revealed increased p53 phosphorylation in HepG2 and PLC/PRF/5 cells but not in HLE cells after combined treatment. Single treatment with IFN-alpha subtypes promoted p53 activation only in PLC/PRF/5 cells. These results propose that IFN-alpha subtypes induce cells to undergo apoptosis through p53 activation directly and indirectly, in collaboration with 5-FU, further suggesting the presence of distinct signal pathways for IFN-alpha-induced apoptosis.

Effects of interferon-alpha subtypes on the TH1/TH2 balance in peripheral blood mononuclear cells from patients with hepatitis virus infection-associated liver disorders

Interferon-alpha (IFN-alpha) has recently been shown to modulate in vitro T helper (Th) 1-driven responses in the peripheral blood mononuclear cells (PBMC) of patients with hepatitis B virus or C virus infection. In this study, we examined the in vitro effects of IFN-alpha subtypes (IFN-alpha1, -alpha2, -alpha5, -alpha8, and -alpha10) on the Th1/Th2 balance in PBMC obtained from patients with hepatitis virus infection-associated liver disorders and chronic hepatitis (CH), in comparison with the effect on healthy control volunteer PBMC. The Th1-type cell percentages and Th1/Th2 ratios were significantly higher in the PBMC of patients when compared with controls both before and after cultivation in vitro, with the IFN-alpha subtypes. The IFNalpha-5 induced an increase in the Th2-type cell percentages in both control and patient PBMC, resulting in that IFN-alpha5 lowered the Th1/Th2 ratio in patients with CH. Furthermore, statistical analysis revealed that IFN-alpha8 significantly promoted an increase in the Th1/Th2 ratios of PBMC from patients with CH and liver cirrhosis (LC) but not that of PBMC from patients with LC-hepatocellular carcinoma (HCC) and HCC. These findings imply that hepatitis virus infection and its disease status modify the effects of IFN-alpha subtypes on Th1 and Th2 immune balance in patients. Our findings should help to elucidate the mechanisms underlying successful IFN therapy for hepatitis virus infection and prevention of hepatocellular carcinogenesis.