Infection risk associated with anti-TNF-α agents: a review

The influence of various therapeutic regimens on early clinical and laboratory response and outcome of children with secondary hemophagocytic lymphohistiocytosis

INTRODUCTION

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a life-threatening syndrome of severe hyperinflammation which is often triggered by infection or autoimmune disease (macrophage activation syndrome - MAS). The aim of our study was to assess the frequency of sHLH/MAS in children treated in our institution and to compare the effectiveness of various therapeutic interventions.

MATERIAL AND METHODS

Between 2005 and 2013, 24 children (age: 1-17 years) were consecutively treated for sHLH/MAS. Therapy was based on glucocorticoids (GCs) in high or standard doses (hd-GCs or sd-GCs), intravenous immunoglobulin (IVIG), and cyclosporin A (CyA). A comparison of selected laboratory and clinical parameters during the first 72 h of treatment and after a week from the last intervention applied in the first 72 h after diagnosis was performed retrospectively.

RESULTS

The majority of patients (14/24, 58%) suffered from sHLH/MAS in the course of an autoimmune disease (12 patients diagnosed with a systemic form of juvenile idiopathic arthritis). We found with a confidence level of 95% that the application of hd-GCs in the first 24 h caused rapid alleviation of fever, reduction of hepatosplenomegaly, and an increase in thrombocytes and s-fibrinogen concentrations. The use of combination therapy with hd-GCs, IVIG, and CyA in the first 72 h caused a faster increase in s-fibrinogen. All patients survived and were alive at the follow-up of 1-8 years.

CONCLUSIONS

The results indicate that treatment of sHLH/MAS based on hd-GCs, CyA and IVIG is an effective therapy in children.

Cerebral artery myogenic reactivity: The next frontier in developing effective interventions for subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a devastating cerebral event that kills or debilitates the majority of those afflicted. The blood that spills into the subarachnoid space stimulates profound cerebral artery vasoconstriction and consequently, cerebral ischemia. Thus, once the initial bleeding in SAH is appropriately managed, the clinical focus shifts to maintaining/improving cerebral perfusion. However, current therapeutic interventions largely fail to improve clinical outcome, because they do not effectively restore normal cerebral artery function. This review discusses emerging evidence that perturbed cerebrovascular "myogenic reactivity," a crucial microvascular process that potently dictates cerebral perfusion, is the critical element underlying cerebral ischemia in SAH. In fact, the myogenic mechanism could be the reason why many therapeutic interventions, including "Triple H" therapy, fail to deliver benefit to patients. Understanding the molecular basis for myogenic reactivity changes in SAH holds the key to develop more effective therapeutic interventions; indeed, promising recent advancements fuel optimism that vascular dysfunction in SAH can be corrected to improve outcome.

Therapeutic Potential of Cholera Toxin B Subunit for the Treatment of Inflammatory Diseases of the Mucosa

Cholera toxin B subunit (CTB) is a mucosal immunomodulatory protein that induces robust mucosal and systemic antibody responses. This well-known biological activity has been exploited in cholera prevention (as a component of Dukoral^® vaccine) and vaccine development for decades. On the other hand, several studies have investigated CTB's immunotherapeutic potential in the treatment of inflammatory diseases such as Crohn's disease and asthma. Furthermore, we recently found that a variant of CTB could induce colon epithelial wound healing in mouse colitis models. This review summarizes the possible mechanisms behind CTB's anti-inflammatory activity and discuss how the protein could impact mucosal inflammatory disease treatment.

Cutaneous side effects of TNF-alpha inhibitors

Since the early 1990s, tumor necrosis factor alpha (TNF-alpha) inhibitors have been successfully used in the treatment of various immune-mediated inflammatory diseases. By now, comprehensive safety data has been compiled. While adverse reactions do occur, they are - in relation to the frequent use of these agents - rare and usually not serious. Cutaneous side effects include local injection site reactions, infections, immune-mediated reactions, and neoplasms. The most common serious adverse events are of an infectious nature. Mycobacteria but also non-mycobacterial pathogens, such as viruses and fungi, may cause serious, even lethal, systemic infections. The present article is meant to review current knowledge with respect to cutaneous side effects of TNF-alpha inhibitors.

Etanercept for steroid-refractory acute graft-versus-host disease: A single center experience

BACKGROUND

Acute graft-versus-host disease (aGVHD) is an important complication of allogeneic stem cell transplantation (alloSCT). High dose glucocorticosteroids, are currently recommended as first-line treatment for grade II-IV aGVHD resulting in overall complete responses (CR) in 40%-50% of patients. No standard second-line regimen has been established. Different options have been reported, including anti-TNFα antibodies.

METHODS

We retrospectively reviewed the outcome of 15 patients with steroid-refractory (SR) aGVHD treated with etanercept at our institution. Patients were transplanted for a hematological malignancy and received either a myeloablative or a non-myeloablative conditioning regimen. Prophylaxis of GVHD consisted of cyclosporin A and mycophenolic acid.

RESULTS

Acute GVHD was diagnosed at a median of 61 days post-transplantation. All patients had grade III aGVHD of the gut. Second-line treatment with etanercept was started at a median of 13 days after initiation of first-line therapy. Overall response rate was 53%, with CR in 3 patients and PR in 5 patients. Median overall survival after initiation of treatment with etanercept was 66 days (range 5-267) for the entire group. Median overall survival was 99 days (range 47-267 days) for responders and 17 days (range 5-66 days) for non-responders (p<0.01). Nevertheless, all patients died. Causes of death were progressive GVHD in 7 patients (47%), infection in 6 patients (40%), cardiac death in 1 patient (6.7%) and relapse in 1 patient (6,7%).

CONCLUSION

Second-line treatment with etanercept does induce responses in SR-aGVHD of the gut but appears to be associated with poor long-term survival even in responding patients.

Nalbuphine analgesic and anti-inflammatory effects on patients undergoing thoracoscopic lobectomy during the perioperative period

This study sought to investigate the analgesic effects of nalbuphine on patients undergoing thoracoscopic lobectomy during the perioperative period, as well as its effects on inflammatory cytokines. We selected 92 patients with early lung cancer who were admitted to Xiangyang No. 1 People's Hospital between January 2016 and December 2016. The patients were randomly divided into control and observation groups (n=46 each). All patients underwent thoracoscopic lobectomy, with those in the observation group receiving intravenous nalbuphine hydrochloride prior to induction (the control group received saline). Intraoperative blood loss, operation time and anesthetic dosages were compared between groups. The analgesic effects during the perioperative period were compared using a visual analogue scale. The adverse effects of anesthetics (nausea, vomiting, dizziness and drowsiness) were compared between the two groups. Finally, serum inflammatory cytokine [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-10] levels were measured using ELISA at 1, 3, 5 and 7 days after operation. There were no significant differences in intraoperative blood loss and operation time between the two groups (p>0.05). However, dosages of propofol and remifentanil used were lower in the observation group than in the control group (p<0.05), and the effective rate of postoperative analgesia in the observation group was significantly higher than that in the control group (p<0.05). The degree of postoperative pain in both groups were lower than preoperative rates (p<0.05), while the incidence of adverse reactions in the observation group was significantly lower than in the control group (p<0.05). Finally, TNF-α, IL-6 and IL-10 levels were significantly lower in the observation group relative to the control group at 1, 3, 5 and 7 days after operation (p<0.05). Therefore, nalbuphine has a significant analgesic effect during thoracoscopic lobectomy. The application of nalbuphine can reduce the incidence of adverse reactions, reduce postoperative inflammatory responses, and promote rapid patient recovery, thus demonstrating the clinical value of nalbuphine.

DOCK8 Drives Src-Dependent NK Cell Effector Function

Mutations in the dedicator of cytokinesis 8 (DOCK8) gene cause an autosomal recessive form of hyper-IgE syndrome, characterized by chronic immunodeficiency with persistent microbial infection and increased incidence of malignancy. These manifestations suggest a defect in cytotoxic lymphocyte function and immune surveillance. However, how DOCK8 regulates NK cell-driven immune responses remains unclear. In this article, we demonstrate that DOCK8 regulates NK cell cytotoxicity and cytokine production in response to target cell engagement or receptor ligation. Genetic ablation of DOCK8 in human NK cells attenuated cytokine transcription and secretion through inhibition of Src family kinase activation, particularly Lck, downstream of target cell engagement or NKp30 ligation. PMA/Ionomycin treatment of DOCK8-deficient NK cells rescued cytokine production, indicating a defect proximal to receptor ligation. Importantly, NK cells from DOCK8-deficient patients had attenuated production of IFN-γ and TNF-α upon NKp30 stimulation. Taken together, we reveal a novel molecular mechanism by which DOCK8 regulates NK cell-driven immunity.

Hypersensitivity and immunologic reactions to biologics: opportunities for the allergist

OBJECTIVE

There has been a great expanse in the use of biological agents during the past decade. However, there are significant differences between biologics and typical pharmaceutical drugs. This review focuses on 3 separate types of adverse reactions to biologics, namely high cytokine reactions, hypersensitivity reactions, and secondary immunodeficiency.

DATA SOURCES

A PubMed literature search restricted to the previous 10 years using combinations of search terms, including omalizumab, rituximab, TGN1412, biologic agent, anaphylaxis, hypogammaglobulinemia, desensitization, and cytokine storm, was performed. The results were manually filtered to identify relevant articles with additional references identified from bibliographies.

STUDY SELECTION

Reports were selected for TGN1412 cytokine storm, omalizumab anaphylaxis and desensitization, rituximab-induced hypogammaglobulinemia, rituximab anaphylaxis and serum sickness, and monoclonal antibody desensitization.

RESULTS

A phase 1 clinical trial using a humanized anti-CD28 monoclonal antibody (TGN1412) caused severe cytokine storm reactions in all 6 subjects, resulting in multiorgan failure. Omalizumab has been reported to cause anaphylaxis in fewer than 0.1% of patients, many with delayed reactions. The mechanism for this anaphylactic reaction is unclear. Rituximab has been associated with hypogammaglobulinemia, serum sickness-like reactions, and anaphylaxis. Rapid drug desensitizations to monoclonal antibodies, including rituximab, suspected of causing immunoglobulin E-mediated reactions have been found to be generally safe and effective.

CONCLUSION

Hypersensitivity reactions and immune dysregulation from biologic agents are not rare. The allergist and immunologist should be involved in managing these patients for optimal care.

Efficacy of isoniazid salvage therapy for latent tuberculosis infection in patients with immune-mediated inflammatory disorders - A retrospective cohort study in Taiwan

BACKGROUND

Active tuberculosis (TB) in patients with latent tuberculosis infection (LTBI) was associated with use of biological agents for immune-mediated inflammatory disorders (IMIDs). For decreasing active TB, isoniazid prophylaxis therapy was administered before biologic therapy among IMID patients with LTBI. However, for patients who had been received biologics for a long time with unknown status of LTBI or exposure history of active TB, the prevalence of LTBI and efficacy of isoniazid therapy were unclear.

METHOD

A retrospective cohort study was conducted during 2012-2014 in a tertiary medical center in Taiwan, and the incidence case of active TB was identified by the national TB registration system on October 1, 2015.

RESULTS

All 382 patients with 1532 person-years were followed up, the initial prevalence of LTBI by positive interferon-gamma releasing assay (IGRA+) was 17.5%. The prevalence of LTBI was increased in elder age (>20%, p < 0.05), chronic kidney disease (33%, p < 0.05), metabolic syndrome (26.3%, p < 0.05), but not related to the type of IMIDs or biologics. The crude incidences of TB were increased in elders (53.3/1000 person-year), abnormal chest film (49.6/1000 person-year), administration of tocilizumab (13.6/1000 person-year), and metabolic syndrome (56.1/1000 person-year), respectively. Among patents with LTBI, the incidence of active TB was lower in patients with isoniazid therapy (9.2/1000 person-year, p = 0.02) than without isoniazid therapy (92.2/1000 person-years), regardless the timing of initiating isoniazid therapy (p > 0.05).

CONCLUSION

Isoniazid therapy can prevent active TB from LTBI despite of the timing of biologics administration.

Anti-inflammatory activity of cecropin-A2 from Musca domestica

This study aimed to investigate the anti-inflammatory activity of Musca domestica cecropin-A2 (Mdc-A2) toward Staphylococcus aureus (S. aureus) to learn more about their immunological functions. RAW264.7 cells were transfected with recombinant lentiviruses introduce pLEX-Mdc-A2into the RAW264.7 cell line (RAW-Mdc-A2). The RAW264.7 cell line with empty pLEX (RAW-pLEX) was produced in the same manner as a negative control. Real-time quantitative reverse transcription PCR (RT-PCR) was performed to analyze the mRNA expression of TNF-a, IL-1β, NFκB-1 and NFκB-2 in S. aureus-stimulated RAW-Mdc-A2 cells and RAW-pLEX cells in untreated cells and cells treated for 3 h, 6 h, 12 h and 24 h. RT-PCR was performed to analyze the mRNA expression of TNF-a, NFκB-1 and NFκB-2 stimulated by Lipoteichoic acid (LTA). Production of TNF-a was detected by enzyme-linked immunosorbent assay (ELISA). Colony counts were used to calculate the number of CFU per mL of cell culture supernatants. The results showed that compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of TNF-a transcript variant 1 (TNF-a-tv-1) at 6 h and 12 h and the mRNA expression of TNF-a transcript variant 2 (TNF-a-tv-2) at 3 h, 6 h and 12 h. Compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of IL-1β-T at 3 h, 6 h and 12 h as well as the mRNA expression of IL-1β at 3 h and 6 h. The expression and production of TNF-a and bacterial burden of cell culture supernatants were significantly down-regulated in RAW-Mdc-A2 cells stimulated by S. aureus, and the expression and production of TNF-a were significantly down-regulated in RAW-Mdc-A2 cells stimulated by LTA. Compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of NFκB-1 at 3 h, 6 h and 12 h as well as the mRNA expression of NFκB-2 at 6 h. Additionally, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by LTA significantly down-regulated the mRNA expression of NFκB-1. In conclusion, Mdc-A2 possesses potent anti-inflammatory activity and potent antimicrobial activity. Additionally, Mdc-A2 may interact with LTA and execute strong anti-inflammatory activity by blocking the activation of NF-κB signaling pathways.

Sirtuin 3 deficiency does not alter host defenses against bacterial and fungal infections

Sirtuin 3 (SIRT3) is the main mitochondrial deacetylase. SIRT3 regulates cell metabolism and redox homeostasis, and protects from aging and age-associated pathologies. SIRT3 may drive both oncogenic and tumor-suppressive effects. SIRT3 deficiency has been reported to promote chronic inflammation-related disorders, but whether SIRT3 impacts on innate immune responses and host defenses against infections remains essentially unknown. This aspect is of primary importance considering the great interest in developing SIRT3-targeted therapies. Using SIRT3 knockout mice, we show that SIRT3 deficiency does not affect immune cell development and microbial ligand-induced proliferation and cytokine production by splenocytes, macrophages and dendritic cells. Going well along with these observations, SIRT3 deficiency has no major impact on cytokine production, bacterial burden and survival of mice subjected to endotoxemia, Escherichia coli peritonitis, Klebsiella pneumoniae pneumonia, listeriosis and candidiasis of diverse severity. These data suggest that SIRT3 is not critical to fight infections and support the safety of SIRT3-directed therapies based on SIRT3 activators or inhibitors for treating metabolic, oncologic and neurodegenerative diseases without putting patients at risk of infection.

Oncostatin M drives intestinal inflammation and predicts response to tumor necrosis factor-neutralizing therapy in patients with inflammatory bowel disease

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are complex chronic inflammatory conditions of the gastrointestinal tract that are driven by perturbed cytokine pathways. Anti-tumor necrosis factor-α (TNF) antibodies are mainstay therapies for IBD. However, up to 40% of patients are nonresponsive to anti-TNF agents, which makes the identification of alternative therapeutic targets a priority. Here we show that, relative to healthy controls, inflamed intestinal tissues from patients with IBD express high amounts of the cytokine oncostatin M (OSM) and its receptor (OSMR), which correlate closely with histopathological disease severity. The OSMR is expressed in nonhematopoietic, nonepithelial intestinal stromal cells, which respond to OSM by producing various proinflammatory molecules, including interleukin (IL)-6, the leukocyte adhesion factor ICAM1, and chemokines that attract neutrophils, monocytes, and T cells. In an animal model of anti-TNF-resistant intestinal inflammation, genetic deletion or pharmacological blockade of OSM significantly attenuates colitis. Furthermore, according to an analysis of more than 200 patients with IBD, including two cohorts from phase 3 clinical trials of infliximab and golimumab, high pretreatment expression of OSM is strongly associated with failure of anti-TNF therapy. OSM is thus a potential biomarker and therapeutic target for IBD, and has particular relevance for anti-TNF-resistant patients.

Risk of tuberculosis in patients treated with TNF-α antagonists: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVES

An increased risk of tuberculosis (TB) has been reported in patients treated with TNF-α antagonists, an issue that has been highlighted in a WHO black box warning. This review aimed to assess the risk of TB in patients undergoing TNF-α antagonists treatment.

METHODS

A systematic literature search for randomised controlled trials (RCTs) was performed in MEDLINE, Embase and Cochrane library and studies selected for inclusion according to predefined criteria. ORs with 95% CIs were calculated using the random-effect model. Subgroup analyses considered the effects of drug type, disease and TB endemicity. The quality of evidence was assessed using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

29 RCTs involving 11 879 patients were included (14 for infliximab, 9 for adalimumab, 2 for golimumab, 1 for etanercept and 3 for certolizumab pegol). Of 7912 patients allocated to TNF-α antagonists, 45 (0.57%) developed TB, while only 3 cases occurred in 3967 patients allocated to control groups, resulting in an OR of 1.94 (95% CI 1.10 to 3.44, p=0.02). Subgroup analyses indicated that patients of rheumatoid arthritis (RA) had a higher increased risk of TB when treated with TNF-α antagonists (OR 2.29 (1.09 to 4.78), p=0.03). The level of the evidence was recommended as 'low' by the GRADE system.

CONCLUSIONS

Findings from our meta-analysis indicate that the risk of TB may be significantly increased in patients treated with TNF-α antagonists. However, further studies are needed to reveal the biological mechanism of the increased TB risk caused by TNF-α antagonists treatment.

Endogenous TNFα orchestrates the trafficking of neutrophils into and within lymphatic vessels during acute inflammation

Neutrophils are recognised to play a pivotal role at the interface between innate and acquired immunities following their recruitment to inflamed tissues and lymphoid organs. While neutrophil trafficking through blood vessels has been extensively studied, the molecular mechanisms regulating their migration into the lymphatic system are still poorly understood. Here, we have analysed neutrophil-lymphatic vessel interactions in real time and in vivo using intravital confocal microscopy applied to inflamed cremaster muscles. We show that antigen sensitisation of the tissues induces a rapid but transient entry of tissue-infiltrated neutrophils into lymphatic vessels and subsequent crawling along the luminal side of the lymphatic endothelium. Interestingly, using mice deficient in both TNF receptors p55 and p75, chimeric animals and anti-TNFα antibody blockade we demonstrate that tissue-release of TNFα governs both neutrophil migration through the lymphatic endothelium and luminal crawling. Mechanistically, we show that TNFα primes directly the neutrophils to enter the lymphatic vessels in a strictly CCR7-dependent manner; and induces ICAM-1 up-regulation on lymphatic vessels, allowing neutrophils to crawl along the lumen of the lymphatic endothelium in an ICAM-1/MAC-1-dependent manner. Collectively, our findings demonstrate a new role for TNFα as a key regulator of neutrophil trafficking into and within lymphatic system in vivo.

Sarcoidosis associated with infliximab therapy in ulcerative colitis: A case report

RATIONALE

Although immunomodulatory therapy has been clearly stated as an important landmark in treatment of ulcerative colitis, significantly improving the quality of life for patients with inflammatory bowel disease, there are several aspects to be considered regarding the possible side-effects of anti-TNF alpha agents. In spite of a good safety profile, biologic TNF antagonists may induce paradoxical inflammation, which can manifest as sarcoid-like granulomatosis, consisting of noncaseating granulomas in the affected organs.

PATIENT CONCERNS

We report the case of a 30-year-old male patient, with no personal or familial history of lung disease, with a personal history of ulcerative colitis (UC), under clinical remission following infliximab therapy in maintenance dose, who was admitted for treatment administration, but also for dyspnea, nocturnal sweating, and nonproductive cough.

DIAGNOSES

Based on clinical manifestations, biological landmarks excluding various infections, CT scan, fibrobronchoscopy with bronchoalveolar lavage for culture and immunohistochemical examination, followed by mediastinoscopy with sampling of paratracheal lymph node, which underwent histopathological examination, the patient was diagnosed with drug- induced stage II pulmonary sarcoidosis.

INTERVENTIONS

Since the patient had developed severe allergic reaction after being administered Infliximab at admission, the biological treatment was immediately discontinued. Following the diagnosis of pulmonary sarcoidosis, corticotherapy was initiated.

PATIENT OUTCOMES

After corticotherapy was initiated, the patient had a favorable outcome at 3 months reevaluation, both regarding the course of ulcerative colitis and sarcoidosis.

LESSONS

Patients under biological therapy using anti-TNF alpha agents must be carefully monitored, in order to early identify potential paradoxical inflammation (such as sarcoidosis) as a side-effect. The drug-related pulmonary disease tends to improve upon withdrawal of the drug, with occasional requirement of steroid treatment. However, a thorough strategy should be assembled in the case of UC relapse in this patient category, with switching to adalimumab or surgical approach as main possibilities.

The role of CD4 cell count as discriminatory measure to guide chemoprophylaxis against Pneumocystis jirovecii pneumonia in human immunodeficiency virus-negative immunocompromised patients: A systematic review

BACKGROUND

In recent years, the incidence of Pneumocystis jirovecii pneumonia (PJP) has increased in immunocompromised patients without human immunodeficiency virus (HIV) infection. Chemoprophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) is highly effective in preventing PJP in both HIV-positive and -seronegative patients. In HIV-positive patients, the risk of PJP is strongly correlated with decreased CD4 cell count. The role of CD4 cell count in the pathogenesis of PJP in non-HIV immunocompromised patients is less well studied. For most immunosuppressive conditions, no clear guidelines indicate whether to start TMP-SMX.

METHOD

We conducted a systematic literature review with the aim to provide a comprehensive overview on the role of CD4 cell counts in managing the risk of PJP in HIV-seronegative patients.

RESULTS

Of the 63 individual studies retrieved, 14 studies report on CD4 cell counts in a variety of immunosuppressive conditions. CD4 cell count were <200/μL in 73.1% of the patients.

CONCLUSION

CD4 cell count <200/μL is a sensitive biomarker to identify non-HIV immunocompromised patients who are at risk for PJP. Measuring CD4 cell counts could help clinicians identify patients who may benefit from TMP-SMX prophylaxis.

Theranostic of biopharmaceuticals

Monoclonal antibodies (mAbs) and fusion proteins with an Fc portion of immunoglobulin G (IgG) are emblematic of the remarkable expansion of biopharmaceuticals. Despite their biological origin, these products display an interindividual variability in their efficacy and/or side effects, which must be taken into consideration. Biological monitoring allowing for adapted prescription and dose adjustments may lead to therapeutic optimization and limitation of the high costs of these drugs. Herein, we review the biological theranostic of mAbs and Fc fusion proteins, including pre-treatment analyses, monitoring of efficacy, therapeutic drug monitoring, and monitoring of side effects. Supported by concrete evidence, a specific interest is given to individualised therapeutic monitoring that combines intention to treat, biomarkers of efficacy and adaptation of serum concentrations.

The antifibrogenic effect of etanercept on development of liver cirrhosis induced by thioacetamide in rats

Liver cirrhosis is an elevating cause of morbidity and mortality worldwide. TNF-α/TNF-R1 signal is implicated in progression of many liver diseases. This study provides histological and ultrastructural view that clarifies the effect of etanercept, a TNF-α inhibitor, on development of thioacetamide (TAA)-induced liver cirrhosis and the accompanied hemosiderosis in rats, highlighting the implication and distribution pattern of hepatic TNF-R1. Sixty male albino rats (Rattus norvegicus) were equally randomized into three groups. Group I served as the control. Liver cirrhosis was triggered in the other two groups by intraperitoneal injection of TAA twice a week for five months. Group II received TAA only, while group III subcutaneously injected with etanercept one hour before TAA, along five months. At the end of the experiment, blood was collected for biochemical analysis and livers were excised for histological, immunohistochemical, and electron microscopical preparations. Rats treated with TAA only developed hepatic cirrhosis accompanied by massive deposition of hemosiderin; strong and widespread expression of hepatic TNF-R1 in sinusoidal endothelial cells (SECs), Kupffer cells (KCs), and many hepatocytes; and frequent appearance of fibrogenic, plasma, and mast cells, at the ultrastructural level. By contrast, administration of etanercept diminished the expression of TNF-R1, attenuated the accumulation of collagen and hemosiderin, and preserved the hepatic histoarchitecture. In conclusion, TNF-α signal via TNF-R1 may be implicated in the mechanism of fibrogenesis and the associated hemosiderosis. Etanercept may provide a promising therapeutic approach not only for attenuating the progression of fibrogenesis, but also for hepatic iron overload-associated disorders.

Functional Characterization of Pneumocystis carinii Inositol Transporter 1

Fungi in the genus Pneumocystis live in the lungs of mammals, where they can cause a fatal pneumonia (PCP [Pneumocystis pneumonia]) in hosts with compromised immune systems. The absence of a continuous in vitro culture system for any species of Pneumocystis has led to limited understanding of these fungi, especially for the discovery of new therapies. We recently reported that Pneumocystis carinii, Pneumocystis murina, and most significantly, Pneumocystis jirovecii lack both enzymes necessary for myo-inositol biosynthesis but contain genes with homologies to fungal myo-inositol transporters. Since myo-inositol is essential for eukaryotic viability, the primary transporter, ITR1, was functionally and structurally characterized in P. carinii The predicted structure of P. carinii ITR1 (PcITR1) contained 12 transmembrane alpha-helices with intracellular C and N termini, consistent with other inositol transporters. The apparent K_m was 0.94 ± 0.08 (mean ± standard deviation), suggesting that myo-inositol transport in P. carinii is likely through a low-affinity, highly selective transport system, as no other sugars or inositol stereoisomers were significant competitive inhibitors. Glucose transport was shown to use a different transport system. The myo-inositol transport was distinct from mammalian transporters, as it was not sodium dependent and was cytochalasin B resistant. Inositol transport in these fungi offers an attractive new drug target because of the reliance of the fungi on its transport, clear differences between the mammalian and fungal transporters, and the ability of the host to both synthesize and transport this critical nutrient, predicting low toxicity of potential inhibitors to the fungal transporter.

IMPORTANCE

myo-Inositol is a sugarlike nutrient that is essential for life in most organisms. Humans and microbes alike can obtain it by making it, which involves only 2 enzymes, by taking it from the environment by a transport process, or by recycling it from other cellular constituents. Inspection of the genomes of the pathogenic fungi of the genus Pneumocystis showed that these pneumonia-causing parasites could not make myo-inositol, as they lacked the 2 enzymes. Instead, we found evidence of inositol transporters, which would import the sugar from the lungs where the fungi reside. In the present report, we characterized the transport of myo-inositol in the fungus and found that the transporter was highly selective for myo-inositol and did not transport any other molecules. The transport was distinct from that in mammalian cells, and since mammals can both make and transport myo-inositol, while Pneumocystis fungi must transport it, this process offers a potential new drug target.

Preterm birth in women with inflammatory bowel disease - the association with disease activity and drug treatment

BACKGROUND

The inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC) have been associated with an increased risk of preterm birth.

MATERIAL AND METHODS

We identified all 246 singleton preterm births among women with IBD between July 2006 and December 2010 as cases and an equal number of controls with IBD from the Swedish national health registers, matched by maternal age, parity and IBD diagnosis (CD/UC). From register data and medical charts, we obtained information on reproductive history, comorbidity, disease activity and drug treatment (corticosteroids, 5-aminosalicylates, sulfasalazine, thiopurines and anti-TNF) as risk factors for preterm birth. Associations were estimated using conditional logistic regression and results were presented as odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

Previous preterm birth was more common among cases, OR 6.13 (95%CI: 2.51-15.01). Significant activity at any time during pregnancy (OR: 2.20; 95%CI: 1.37-3.53), and in particular both in early and in late pregnancy, was more common for cases (OR: 4.78 95%; CI: 2.10-10.9). The OR for immunosuppressive treatment with thiopurines or anti-TNF was 1.88 (1.04-3.39) without significant activity and 12.78 (95%CI: 3.68-44.72) with. The risk for women who discontinued thiopurines was 6.56 (1.44-29.82).

CONCLUSIONS

Significant activity and immunosuppressive treatment was associated with preterm birth, particularly in women with both. The existing recommendations to aim at maintaining quiescent disease during pregnancy, even if it means continuing immunosuppressive treatment, are rational.

Increased healthcare resource utilization in higher disease activity levels in initiators of TNF inhibitors among US rheumatoid arthritis patients

OBJECTIVE

Determine healthcare resource utilization (HCRU) in biologic-naïve initiators of TNF inhibitors (TNFis) associated with their disease activity from a national cohort of rheumatoid arthritis (RA) patients.

METHODS

RA patients were identified at their first TNFi initiation (index date) in the Corrona registry. Patients with age of RA onset <18, comorbid psoriasis/psoriatic arthritis, fibromyalgia, or osteoarthritis were excluded. Patients were categorized into disease activity (DA) strata by the lowest level of DA (and sustaining low levels for at least two visits) using the Clinical Disease Activity Index (CDAI) across all visits in Corrona while on a TNFi during 1 year after initiation. Rates of all-cause and RA-related hospitalizations, rheumatologist visits, and joint surgeries while on TNFi therapy were reported and compared across DA levels along with the incidence rate ratio (IRR) adjusted for age, gender, and RA duration using Poisson mixed models.

RESULTS

Of 1931 RA patients: 15% achieved sustained remission, 22% remission, 14% sustained low DA, 23% low DA and 27% moderate/high DA (M/HDA). Those in M/HDA had statistically higher rates of hospitalizations (37.3 per 100 patient years (py), 95% CI: 31.6-43.7 and joint surgeries (20.8 per 100 py, 95% CI: 16.6-25.8) compared to the sustained remission cohort, resulting in respective IRRs of 2.3 (p < 0.001) and 1.7 (p = 0.046).

CONCLUSION

Many biologic naïve RA patients initiating TNFi failed to achieve sustained remission during a 1 year period while remaining on TNFi therapy. Patients in higher DA levels had higher HCRU rates vs. patients in sustained remission, suggesting that achieving treat-to-target goals would reduce health care expenses.

Impact of the microbial derived short chain fatty acid propionate on host susceptibility to bacterial and fungal infections in vivo

Short chain fatty acids (SCFAs) produced by intestinal microbes mediate anti-inflammatory effects, but whether they impact on antimicrobial host defenses remains largely unknown. This is of particular concern in light of the attractiveness of developing SCFA-mediated therapies and considering that SCFAs work as inhibitors of histone deacetylases which are known to interfere with host defenses. Here we show that propionate, one of the main SCFAs, dampens the response of innate immune cells to microbial stimulation, inhibiting cytokine and NO production by mouse or human monocytes/macrophages, splenocytes, whole blood and, less efficiently, dendritic cells. In proof of concept studies, propionate neither improved nor worsened morbidity and mortality parameters in models of endotoxemia and infections induced by gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae), gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae) and Candida albicans. Moreover, propionate did not impair the efficacy of passive immunization and natural immunization. Therefore, propionate has no significant impact on host susceptibility to infections and the establishment of protective anti-bacterial responses. These data support the safety of propionate-based therapies, either via direct supplementation or via the diet/microbiota, to treat non-infectious inflammation-related disorders, without increasing the risk of infection.

Herpes zoster in psoriasis patients undergoing treatment with biological agents: prevalence, impact, and management challenges

As TNF-α is a major factor in the immune defense against herpes zoster (HZ); an increased incidence and severity of HZ cases were suspected in patients undergoing treatment with TNF antagonists. Several studies and clinical experience provided evidence that the incidence of HZ increases by twofold to threefold in this patient category. The number of severe cases of HZ, with multisegmental, disseminated cutaneous, and/or systemic involvement, is also increased. Concerning psoriasis patients under biologicals, the clinician should be more alert for an eventual HZ event, in particular during the first year of biological treatment, and be aware of the possibility of more severe HZ cases. HZ may also undergo an age-shift toward younger patients. Rapid identification of risk factors for severe HZ, such as severe prodromal pains and/or the presence of satellite lesions, is recommended. The treatment recommendations of HZ in this patient group are identical to the recently published guidelines for the management of HZ. The live attenuated viral vaccine OKA/Merck strain anti-HZ vaccination is recommended before initiating biological treatment in psoriasis patients. The new adjuvanted anti-HZ vaccine will probably also benefit patients while on biological treatment.

Fulminant Hepatic Failure in a Patient with Crohn's Disease on Infliximab Possibly Related to Reactivation of Herpes Simplex Virus 2 Infection

HSV hepatitis is a rare but often fatal cause of liver failure which tends to affect immunocompromised individuals. Early treatment with Acyclovir has been shown to reduce mortality in HSV hepatitis making recognition of the condition critically important. Here, we present a case of HSV hepatitis in a young woman with Crohn's disease on Prednisone, Azathioprine, and Infliximab. We discuss the clinical presentation of HSV hepatitis as well as the possible causes of hepatitis in a patient on these medications. This case helps demonstrate the importance of early clinical suspicion for HSV in undifferentiated fulminate liver failure. It is also the first reported case of HSV hepatitis in a patient on Infliximab, raising the possibility of HSV reactivation in patients on Infliximab.

Lower Respiratory Tract Infections

This review will focus on the infectious etiologies and more common noninfectious causes of lower respiratory tract syndromes among major immunosuppressed populations. The changing epidemiology of infections in the era of highly active antiretroviral therapy (HAART) in the case of HIV-positive patients and the impacts of both newer immune-suppressant therapies and anti-infective prophylaxis for other immunocompromised hosts will be discussed, with emphasis on diagnostic approaches and practice algorithms.

Selenium Deficiency-Induced Inflammation and Increased Expression of Regulating Inflammatory Cytokines in the Chicken Gastrointestinal Tract

Selenium (Se), a nutritionally essential trace element, plays an important role in various aspects of health for a wide range of species, including birds. Se deficiency inhibits the growth of immune organs and decreases immune function, leading to many inflammatory diseases. The present study determined the effects and mechanism of dietary Se deficiency on gastrointestinal tract tissue inflammation. The histopathological changes showed that Se deficiency induced inflammatory lesions in the gastrointestinal tract tissues (glandular stomach, gizzard, duodenum, small intestine, and rectum). The expression levels of PTGE (prostagland E synthase), COX-2 (cyclooxygenase-2), TNF-α (tumor necrosis factor α), and NF-κB (nuclear transfer factor κB) in the gastrointestinal tract tissues (glandular stomach, gizzard, duodenum, small intestine, and rectum) were determined by qPCR on days 15, 25, 35, 45, and 55, respectively. The results showed that Se deficiency induced high expression levels of PTGE, COX-2, TNF-α, and NF-κB in the gastrointestinal tract tissues. The effects were more obvious in the duodenum and small intestine than those in the glandular stomach, gizzard, and rectum. In addition, the expression levels of these proteins in the gastrointestinal tract tissue increased in a time-dependent manner with Se deficiency feeding time. Furthermore, Se deficiency induced the production of pro-inflammatory factors, thus aggravating inflammatory lesions in the gastrointestinal tract. The effect of Se deficiency on inflammation and other gastrointestinal tract diseases should be further studied.

Selenium Deficiency Facilitates Inflammation Following S. aureus Infection by Regulating TLR2-Related Pathways in the Mouse Mammary Gland

Selenium (Se) is an essential micronutrient affecting various aspects of health. Se deficiency has been associated with inflammation and immune responses. Mastitis poses a serious problem for humans and animals in the postpartum period. Staphylococcus aureus (S. aureus) is the most common infectious bacterial pathogen associated with mastitis. The present study sought to determine the effects and underlying mechanism of dietary Se on S. aureus-induced inflammation using a model of mouse mastitis. ELISA and Western blotting were performed to detect protein levels. Quantitative PCR (qPCR) was performed to detect messenger RNA (mRNA) levels. The histopathological changes indicated that Se deficiency resulted in increased inflammatory lesions in S. aureus mastitis, whereas Se deficiency did not induce inflammatory lesions in the mammary gland. Myeloperoxidase (MPO) activity was increased in Se-deficient mice with S. aureus mastitis. Analysis of cytokine mRNA and protein showed that Se deficiency leads to increased TNF-α, IL-1β, and IL-6 production in S. aureus mastitis. In addition, Se deficiency enhanced the mRNA and protein expressions of toll-like receptor 2 (TLR2), which were originally upregulated by S. aureus in the mammary gland tissues and human embryonic kidney 293 (HEK293)-mTLR2 cells. When Se-deficient mice were infected with S. aureus, the phosphorylation of IκB, nuclear factor-κB (NF-κB), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 was greatly increased. The results indicate that Se deficiency could intensify the inflammatory reaction in S. aureus mastitis. This work contributes to the exploration of new methods of preventing or treating of S. aureus mastitis and other infectious diseases.

Overview of Infections in the Immunocompromised Host

Understanding the components of the immune system that contribute to host defense against infection is key to recognizing infections that are more likely to occur in an immunocompromised patient. In this review, we discuss the integrated system of physical barriers and of innate and adaptive immunity that contributes to host defense. Specific defects in the components of this system that predispose to particular infections are presented. This is followed by a review of primary immunodeficiency diseases and secondary immunodeficiencies, the latter of which develop because of a specific illness or condition or are treatment-related. The effects of treatment for neoplasia, autoimmune diseases, solid organ and stem cell transplants on host defenses are reviewed and associated with susceptibility to particular infections. In conclusion, an approach to laboratory screening for a suspected immunodeficiency is presented. Knowledge of which host defects predispose to specific infections allows clinicians to prevent, diagnose, and manage infections in their immunocompromised patients most effectively.

Death of a 29-Year-Old Male from Undifferentiated Sepsis

Tumour necrosis factor alpha inhibitors, such as infliximab, and other biologic agents are associated with increased risk of opportunistic infection, including tuberculosis. Tuberculosis infections associated with infliximab tend to present atypically and can be difficult to diagnose, as they are more likely to manifest as extrapulmonary or disseminated disease. The authors report a case involving a 29-year-old male patient who died following 16 days of treatment for undifferentiated sepsis and who was found on autopsy to have widespread disseminated tuberculosis. Prior to the onset of illness, the patient had received infliximab for the treatment of Crohn's disease. Following discussion of the case, the authors review the definition of adverse events, provide a root cause analysis of the cognitive errors and breakdowns in the health care system that contributed to the reported outcome, and identify opportunities to address these breakdowns and improve patient safety measures for future cases.

Convergent Transcription of Interferon-stimulated Genes by TNF-α and IFN-α Augments Antiviral Activity against HCV and HEV

IFN-α has been used for decades to treat chronic hepatitis B and C, and as an off-label treatment for some cases of hepatitis E virus (HEV) infection. TNF-α is another important cytokine involved in inflammatory disease, which can interact with interferon signaling. Because interferon-stimulated genes (ISGs) are the ultimate antiviral effectors of the interferon signaling, this study aimed to understand the regulation of ISG transcription and the antiviral activity by IFN-α and TNF-α. In this study, treatment of TNF-α inhibited replication of HCV by 71 ± 2.4% and HEV by 41 ± 4.9%. Interestingly, TNF-α induced the expression of a panel of antiviral ISGs (2-11 fold). Blocking the TNF-α signaling by Humira abrogated ISG induction and its antiviral activity. Chip-seq data analysis and mutagenesis assay further revealed that the NF-κB protein complex, a key downstream element of TNF-α signaling, directly binds to the ISRE motif in the ISG promoters and thereby drives their transcription. This process is independent of interferons and JAK-STAT cascade. Importantly, when combined with IFN-α, TNF-α works cooperatively on ISG induction, explaining their additive antiviral effects. Thus, our study reveals a novel mechanism of convergent transcription of ISGs by TNF-α and IFN-α, which augments their antiviral activity against HCV and HEV.

Emerging strategies for cancer immunoprevention

The crucial role of the immune system in the formation and progression of tumors has been widely accepted. On one hand, the surveillance role of the immune system plays an important role in endogenous tumor prevention, but on the other hand, in some special circumstances such as in chronic inflammation, the immune system can actually contribute to the formation and progression of tumors. In recent years, there has been an explosion of novel targeted immunotherapies for advanced cancers. In the present manuscript, we explore known and potential various types of cancer prevention strategies and focus on nonvaccine-based cancer preventive strategies targeting the immune system at the early stages of tumorigenesis.

Immunogenicity of infliximab and adalimumab: what is its role in hypersensitivity and modulation of therapeutic efficacy and safety?

INTRODUCTION

TNF-α inhibitors have demonstrated efficacy both as monotherapy and in combination with disease-modifying antirheumatic drugs (DMARDs) in the treatment of chronic inflammatory immune-mediated diseases such as rheumatoid arthritis, Crohn's disease, ankylosing spondylitis, psoriasis and/or psoriatic arthritis, and may be administered off-label to treat disseminated granuloma annulare systemic lupus erythematosus and systemic sclerosis. There are several TNF-α inhibitors available for clinical use including infliximab, adalimumab, golimumab, certolizumab pegol and etanercept.

AREAS COVERED

infliximab and adalimumab can induce the development of anti-infliximab (anti-IFX) and anti-adalimumab (anti-ADA) monoclonal antibodies (mAbs). In this review, we discuss the impact of anti-IFX and anti-ADA mAbs upon efficacy and safety of these biological agents.

EXPERT OPINION

IgG/IgE neutralizing antibodies against infliximab and adalimumab decrease the possibility of achieving a minimal disease activity state or clinical remission, decrease drug survival, increase the need for doctors to prescribe a higher drug dosage and, finally, favor the occurrence of adverse events. Concomitant administration of DMARDs such as methotrexate or leflunomide prevents the development of neutralizing Abs against infliximab and adalimumab.

Use of biologic agents for rheumatic diseases in pregnancy

Biologic agents have ushered a new era in the treatment of inflammatory rheumatic diseases. In recent years, several biologic agents have been approved by food and drug administration and have significantly improved outcomes for patients with immune mediated inflammatory disorders including rheumatic and inflammatory bowel diseases. The most common used biologic therapeutic agents are tumor necrosis factor inhibitors (etanercept, infliximab, adalimumab, certolizumab pegol, and golimumab), an interleukin (IL)-6 inhibitor (tocilizumab), an IL-1 receptor antagonist (anakinra), an anti-CD-20 antibody (rituximab), and a T cell co-stimulation modulator (abatacept). Their use during pregnancy has been controversial because of absence of controlled studies which have enrolled pregnant women. This brief overview provides published data on use of biologic agents for the treatment of rheumatic diseases in pregnancy.