Administration of intravenous immunoglobulin (IVIG) in vivo--down-regulatory effects on the IL-1 system

Update on Intravenous Immunoglobulin in Neurology: Modulating Neuro-autoimmunity, Evolving Factors on Efficacy and Dosing and Challenges on Stopping Chronic IVIg Therapy

In the last 25 years, intravenous immunoglobulin (IVIg) has had a major impact in the successful treatment of previously untreatable or poorly controlled autoimmune neurological disorders. Derived from thousands of healthy donors, IVIg contains IgG1 isotypes of idiotypic antibodies that have the potential to bind pathogenic autoantibodies or cross-react with various antigenic peptides, including proteins conserved among the "common cold"-pre-pandemic coronaviruses; as a result, after IVIg infusions, some of the patients' sera may transiently become positive for various neuronal antibodies, even for anti-SARS-CoV-2, necessitating caution in separating antibodies derived from the infused IVIg or acquired humoral immunity. IVIg exerts multiple effects on the immunoregulatory network by variably affecting autoantibodies, complement activation, FcRn saturation, FcγRIIb receptors, cytokines, and inflammatory mediators. Based on randomized controlled trials, IVIg is approved for the treatment of GBS, CIDP, MMN and dermatomyositis; has been effective in, myasthenia gravis exacerbations, and stiff-person syndrome; and exhibits convincing efficacy in autoimmune epilepsy, neuromyelitis, and autoimmune encephalitis. Recent evidence suggests that polymorphisms in the genes encoding FcRn and FcγRIIB may influence the catabolism of infused IgG or its anti-inflammatory effects, impacting on individualized dosing or efficacy. For chronic maintenance therapy, IVIg and subcutaneous IgG are effective in controlled studies only in CIDP and MMN preventing relapses and axonal loss up to 48 weeks; in practice, however, IVIg is continuously used for years in all the aforementioned neurological conditions, like is a "forever necessary therapy" for maintaining stability, generating challenges on when and how to stop it. Because about 35-40% of patients on chronic therapy do not exhibit objective neurological signs of worsening after stopping IVIg but express subjective symptoms of fatigue, pains, spasms, or a feeling of generalized weakness, a conditioning effect combined with fear that discontinuing chronic therapy may destabilize a multi-year stability status is likely. The dilemmas of continuing chronic therapy, the importance of adjusting dosing and scheduling or periodically stopping IVIg to objectively assess necessity, and concerns in accurately interpreting IVIg-dependency are discussed. Finally, the merit of subcutaneous IgG, the ineffectiveness of IVIg in IgG4-neurological autoimmunities, and genetic factors affecting IVIg dosing and efficacy are addressed.

Intravenous Immunoglobulin for Overwhelming Postsplenectomy Infection

Overwhelming postsplenectomy infection (OPSI) is a life-threatening condition causing fulminant bacteremia in asplenic patients. Intravenous immunoglobulin (IVIG) therapy is theoretically effective for OPSI. Herein, we present a case of OPSI treated successfully with IVIG, along with results of a literature review. An asplenic 70-year-old male with acute ischemic stroke presented with rapid and fulminant septic shock from pneumococcus pneumonia and bacteremia. Resuscitation and antibiotics including IVIG therapy were instituted. The patient survived with favorable outcomes. We analyzed all case reports or case series of OPSI from 1971 through 2017. Cases with IVIG treatment showed a significantly higher survival rate than those without IVIG, even with multivariable regression analysis, suggesting IVIG as an independent predictive factor for survival. It suggests that IVIG is effective for OPSI and that it can be regarded as an adjunctive treatment option for OPSI.

Use of Intravenous Immunoglobulins in Sepsis Therapy-A Clinical View

Sepsis is a life-threatening organ dysfunction, defined by a dysregulated host immune response to infection. During sepsis, the finely tuned system of immunity, inflammation and anti-inflammation is disturbed in a variety of ways. Both pro-inflammatory and anti-inflammatory pathways are upregulated, activation of the coagulation cascade and complement and sepsis-induced lymphopenia occur. Due to the manifold interactions in this network, the use of IgM-enriched intravenous immunoglobulins seems to be a promising therapeutic approach. Unfortunately, there is still a lack of evidence-based data to answer the important questions of appropriate patient populations, optimal timing and dosage of intravenous immunoglobulins. With this review, we aim to provide an overview of the role of immunoglobulins, with emphasis on IgM-enriched formulations, in the therapy of adult patients with sepsis and septic shock.

Risiken und Chancen von Immuntherapien in Zeiten der Coronavirus-2019-Pandemie

Immuntherapien stellen die essenzielle Grundlage der Behandlung von neuroinflammatorischen Erkrankungen dar. In Zeiten der Coronavirus-2019 (COVID-19)-Pandemie ergibt sich im klinischen Alltag jedoch zunehmend die Frage, ob eine Immuntherapie bei neurologischen Patienten aufgrund des potenziellen Infektionsrisikos eingeleitet, intensiviert, pausiert oder gar beendet werden sollte. Unsicherheit besteht v. a. deshalb, weil verschiedene nationale und internationale Fachgesellschaften diesbezüglich unterschiedliche Empfehlungen veröffentlichten. In diesem Artikel soll ein Überblick über die Wirkmechanismen von Immuntherapien und den daraus abzuleitenden Infektionsrisiken in Bezug auf COVID-19 (durch den Coronavirus verursachte Erkrankung) gegeben werden. Potenzielle Chancen und vorteilhafte Effekte einzelner Substrate in der Akuttherapie von COVID-19 werden diskutiert.

Merits and culprits of immunotherapies for neurological diseases in times of COVID-19

Immunosuppression and immunomodulation are valuable therapeutic approaches for managing neuroimmunological diseases. In times of the Coronavirus disease 2019 (COVID-19) pandemic, clinicians must deal with the question of whether immunotherapy should currently be initiated or discontinued in neurological patients. Uncertainty exists especially because different national medical associations publish different recommendations on the extent to which immunotherapies must be continued, monitored, or possibly switched during the current pandemic. Based on the most recently available data both about the novel coronavirus and the approved immunotherapies for neurological diseases, we provide an updated overview that includes current treatment strategies and the associated COVID-19 risk, but also the potential of immunotherapies to treat COVID-19.

Effect of immunomodulation on cardiac remodelling and outcomes in heart failure: a quantitative synthesis of the literature

Aims

Immunomodulation in heart failure (HF) has been studied in several randomized controlled trials (RCTs) with variable effects on cardiac structure, function, and outcomes. We sought to determine the effect of immunomodulation on left ventricular ejection fraction (LVEF), LV end‐diastolic dimension (LVEDD), and all‐cause mortality in patients with HF with reduced ejection fraction (HFrEF) through meta‐analyses and trial sequential analyses (TSAs) of RCTs.

Methods and results

PubMed, Embase®, Cochrane CENTRAL, and http://ClinicalTrials.gov were systematically reviewed to identify RCTs that studied the effects of immunomodulation in patients with HFrEF. The primary endpoint in this analysis was change in LVEF. Secondary outcomes were changes in LVEDD and all‐cause mortality. TSA was used to quantify the statistical reliability of data in the cumulative meta‐analyses. Nineteen RCTs with 1341 HFrEF subjects were eligible for analyses. The aetiology of HF, specific immunomodulation strategy, and treatment duration were variable across trials. Immunomodulation led to a greater improvement in LVEF [mean difference: +5.7% 95% confidence interval (CI): 3.0–8.5%, P < 0.001] and reduction in LVEDD (mean difference: −3.7 mm, 95% CI: −7.0 to −0.4 mm, P = 0.028) than no immunomodulation in meta‐analyses and TSAs. We observed a non‐significant decrease in all‐cause mortality among those on immumomodulation (risk ratio: 0.7, 95% CI: 0.4–1.3, P = 0.234), but the Z‐curve for cumulative treatment effect of immunomodulation in the TSA did not cross the boundary of futility.

Conclusions

Immunomodulation led to improved cardiac structure and function in patients with HFrEF. While these benefits did not translate into a significant improvement in mortality, our analysis suggests that larger studies of targeted immunomodulation are needed to understand the true benefits.

Neuroinflammatory Nexus of Pediatric Epilepsy

A rapidly growing body of evidence supports the premise that neuroinflammation plays an important role in initiating and sustaining seizures in a range of pediatric epilepsies. Clinical and experimental evidence indicate that neuroinflammation is both an outcome and a contributor to seizures. In this manner, seizures that arise from an initial insult (e.g. infection, trauma, genetic mutation) contribute to an inflammatory response that subsequently promotes recurrent seizures. This cyclical relationship between seizures and neuroinflammation has been described as a 'vicious cycle.' Studies of human tissue resected for surgical treatment of refractory epilepsy have reported activated inflammatory and immune signaling pathways, while animal models have been used to demonstrate that key inflammatory mediators lead to increased seizure susceptibility. Further characterization of the molecular mechanisms involved in this cycle may ultimately enable the development of new therapeutic approaches for the treatment of epilepsy. In this brief review we focus on key inflammatory mediators that have become prominent in recent literature of epilepsy, including newly characterized microRNAs and their potential role in neuroinflammatory signaling.

Single versus divided administration of intravenous immunoglobulin for sepsis: a retrospective and historical control study

BACKGROUND

Intravenous immunoglobulin (IVIG) is regarded as effective, theoretically, for sepsis. The IVIG regimen for severe infection covered by Japanese health insurance is administration of 5 g/day for three days: an extremely low dosage. We investigated its effectiveness by comparison between divided dosage and single dosage of 15 g for one day.

METHODS

Patients who were admitted to our hospital's Emergency Medical Center and treated with IVIG for sepsis were included and were analyzed retrospectively. The dosage regimen was 5 g for three days in the early half period, and 15 g for one day in the latter half period employing the same indication criteria.

RESULTS

Each group included 57 patients. No significant difference was found in their baseline characteristics, survival probability, or length of mechanical ventilation. However, the ICU stay and hospital stay lengths were shortened significantly by administration of the single dosage regimen. Disseminated intravascular coagulopathy markers and inflammatory indices were improved significantly earlier in the 15 g for one day group. Regarding adverse events, no significant difference was found.

CONCLUSIONS

For sepsis treatment, single administration of 15 g IVIG for one day improved the condition and inflammation earlier than divided dosage.

Mechanistic effects of IVIg in neuroinflammatory diseases: conclusions based on clinicopathologic correlations

The mechanisms of action of IVIg on immunoregulatory and neuroinflammatory network have been predominantly based on in vitro experiments and animal studies, rather than direct effects on human tissues. Based on clinicopathologic correlations and tissues obtained before and after IVIg therapy, the better documented and clinically-relevant in-vivo actions of IVIg include effects on: a) Antibodies. An extracted antigen-specific anti-immunoglobulin (idiotypic) fraction appears partially responsible for its effect in myasthenia gravis and GBS; b) Complement. Sera from Dermatomyositis (DM) patients responding to IVIg, inhibit complement consumption and intercept MAC formation leading to disappearance of MAC deposits in the repeated muscle biopsies and normalization of muscle tissue; c) Genes. In repeated muscle biopsies from DM patients who improved after IVIg, but not from Inclusion-Body-Myositis (IBM) who did not improve, there is a 2-fold alteration of 2206 tissue genes associated with inflammation, fibrosis, tissue remodeling and regeneration; and d) degenerative-proinflammatory molecules and β-amyloid, implicated in neurodegenerative CNS diseases and IBM. In repeated muscle biopsies of IBM patients who did not respond to IVIg, the mRNA or protein expression for chemokines, IFN-γ, TGF-ß, IL-10, Ubiquitin and aB-crystallin is reduced, but not for the key molecules ICOS, ICOSL, IL-6, IL1-β, perforin, APP, nitric oxide synthase and nitrotyrosine, in spite of good IVIg penetration in muscles. Collectively, the selective effectiveness of IVIg in human diseases seems to correlate in vivo with inhibition of causative inflammatory mediators. Study of accessible tissues before and after therapy and clinicopathologic correlations, may help explain the differential effect of IVIg in autoimmune or neuroinflammatory diseases.

Specific antibody in IV immunoglobulin for postsplenectomy sepsis

OBJECTIVE

Overwhelming postsplenectomy infection progresses rapidly and shows unacceptably high mortality even when treated with optimal antibiotics. Recent reports have described beneficial effects of intravenous immunoglobulin in sepsis. However, the underlying mechanisms, especially the roles of the pathogen-specific antibody fraction in intravenous immunoglobulin, remain unclear. We investigated the effects of intravenous immunoglobulin on overwhelming postsplenectomy infection and the role of pathogen-specific antibody.

DESIGN

Prospective, controlled, and randomized animal study.

SETTING

University laboratory.

SUBJECTS

Male C57BL/6JJcl mice.

INTERVENTIONS

Mice underwent splenectomy or a sham operation at 8 weeks old. At 4 weeks after the operation, mice were injected intravenously with 106 colony-forming units pneumococcus. Intraperitoneal injection of 300 mg/kg IV immunoglobulins was conducted simultaneously with infection. Specific antibody-depleted IV immunoglobulin prepared using immunoprecipitation was also injected into the animals.

MEASUREMENTS AND MAIN RESULTS

IV immunoglobulin markedly improved splenectomized mice survival. Removal of pneumococcus-specific antibody canceled it completely. Fluorescence microscopy results indicated significantly increased phagocytosis of antibody-bound bacteria in the livers of splenectomized mice treated with intact IV immunoglobulins. Immunomodulation, including suppression of marginal zone B-cell activation, was induced by IV immunoglobulin.

CONCLUSIONS

IV immunoglobulin showed a significantly protective effect on overwhelming postsplenectomy infection via enhancement of specific antibody-mediated phagocytosis in the liver. Specific antibody, more than immunological modulation, is crucial for effects of IV immunoglobulin on overwhelming postsplenectomy infection.

Up-regulation of immunoglobulin G gene expression in the hippocampus of rats subjected to acute immobilization stress

Immunoglobulin G (IgG) is thought to be produced by matured B lymphocytes, however, it was recently found to be synthesized in neurons of the brain, especially showing higher expression level in the hippocampus. To study the possible effects of IgG in the hippocampus, we examined IgG protein and mRNA expressions in rat hippocampal neurons with immunohistochemistry, immunofluorescence, in situ hybridization and laser microdissection-assisted RT-PCR. Increased IgG expressions at both protein and mRNA levels were detected in the hippocampus of an acute immobilization stress model of rat. No change was observed in the cortex or the thalamus. Furthermore, the microtubule-associated protein 2 (MAP2) and β III tubulin proteins did not show significant changes. Based on these findings, we hypothesize that hippocampal IgG may play a key role in adverse circumstances such as stress. The finding of increased IgG expression in the hippocampus following stress may also provide possibilities for developing antidepressant medication.

Bench-to-bedside review: Immunoglobulin therapy for sepsis - biological plausibility from a critical care perspective

Sepsis represents a dysregulated host response to infection, the extent of which determines the severity of organ dysfunction and subsequent outcome. All trialled immunomodulatory strategies to date have resulted in either outright failure or inconsistent degrees of success. Intravenous immunoglobulin (IVIg) therapy falls into the latter category with opinion still divided as to its utility. This article provides a narrative review of the biological rationale for using IVIg in sepsis. A literature search was conducted using the PubMed database (1966 to February 2011). The strategy included the following text terms and combinations of these: IVIg, intravenous immune globulin, intravenous immunoglobulin, immunoglobulin, immunoglobulin therapy, pentaglobin, sepsis, inflammation, immune modulation, apoptosis. Preclinical and extrapolated clinical data of IVIg therapy in sepsis suggests improved bacterial clearance, inhibitory effects upon upstream mediators of the host response (for example, the nuclear factor kappa B (NF-κB) transcription factor), scavenging of downstream inflammatory mediators (for example, cytokines), direct anti-inflammatory effects mediated via Fcγ receptors, and a potential ability to attenuate lymphocyte apoptosis and thus sepsis-related immunosuppression. Characterizing the trajectory of change in immunoglobulin levels during sepsis, understanding mechanisms contributing to these changes, and undertaking IVIg dose-finding studies should be performed prior to further large-scale interventional trials to enhance the likelihood of a successful outcome.

Potential biomarkers for monitoring therapeutic response in patients with CIDP

Although the majority of patients with CIDP variably respond to intravenous immunoglobulin (IVIg), steroids, or plasmapheresis, 30% of them are unresponsive or insufficiently responsive to these therapies. The heterogeneity in therapeutic responses necessitates the need to search for biomarkers to determine the most suitable therapy from the outset and explore the best means for monitoring disease activity. The ICE study, which led to the first FDA-approved indication for IVIg in CIDP, has shown that maintenance therapy prevents relapses and axonal loss. In this paper, the multiple actions exerted by IVIg on the immunoregulatory network of CIDP are discussed as potential predictors of response to therapies. Emerging molecular markers, promising in identifying responders to IVIg from non-responders, include modulation of FcγRIIB receptors on monocytes and genome-wide transcription studies related to inflammatory mediators, demyelination, or axonal degeneration. Skin biopsies, Peripheral Blood Lymhocytes, CSF, and sera are accessible surrogate tissues for further exploring these molecules during therapies.

Recurrent fever syndromes in patients after recovery from Kawasaki syndrome

The recurrence of fever in a child with a history of Kawasaki syndrome (KS) poses a dilemma for clinicians who must consider the possibility of recurrent KS. In this report we present the cases of 4 patients who presented with classical symptoms of KS, were successfully treated with intravenous immunoglobulin, and later experienced a reappearance of inflammatory symptoms in a pattern consistent with a recurrent fever syndrome. The association of these syndromes within the same patient suggests that some patients may have a genetic propensity toward altered immune responses and autoinflammatory syndromes. We propose that these 2 syndromes exist within a family of febrile disorders related to innate immune dysregulation.

Gamma-globulin inhibits superantigen-induced lymphocyte proliferation and cytokine production

BACKGROUND

High-dose pooled human immunoglobulin (PHIG) treatment is sometimes effective in superantigen related inflammatory diseases, such as toxic shock syndrome and Kawasaki disease. Neutralizing antibody to superantigen might provide protection, but antigen independent immune regulation of PHIG is also a proposed mechanism.

METHODS

Staphylococcal enterotoxin B (SEB)-specific IgG antibody in PHIG products (Venoglobulin IH(R)) was detected by ELISA. The suppressive effect of PHIG or its fragments on proliferation and cytokine (IL-4 and IFN-gamma) production from SEB-stimulated peripheral blood mononuclear cells was examined.

RESULTS

SEB-specific IgG was detected in PHIG products. PHIG (6.25-25mg/ml) suppressed SEB-induced proliferation and cytokine production in a dose-dependent manner. Fab and F (ab') 2 fractions of PHIG also suppressed the responses, but depletion of SEB-specific antibody from PHIG did not affect the inhibitory effects. The Fc fragment of PHIG also showed partial, but significant suppression.

CONCLUSIONS

These data suggested the possibility that PHIG suppressed SEB-induced proliferation and cytokine production by some mechanisms independent of the presence of neutralizing antibody.

Effects of Intravenous Immunoglobulins on Peripheral Blood Mononuclear Cell Activation in Vitro

The therapeutic effects of intravenous immunoglobulins (IVIGs) on different chronic inflammatory and autoimmune diseases is well appreciated, though clinical studies with high-evidence levels are largely missing. Similar to the broad spectrum of diseases and their underlying etiopathogenic background, the mechanisms of action seem heterogenous and multifold. Several studies addressing in vitro and in vivo effects of IVIG on various immunological parameters have been described with partly contradictory results. In this study immunoglobulins and stabilizers present in commercial IVIG preparations were studied in regard to the in vitro proliferation and cytokine production of peripheral blood mononuclear cells when stimulated with phytohemagglutinin (PHA), interleukin 2, and tetanus toxoid. Whereas the immunoglobulins stimulate the proliferation of PBMCs and decrease IFNgamma secretion, stabilizers of IVIG seem to inhibit the proliferation of PBMCs while increasing the secretion of IFN gamma. These effects have to be taken into account when balancing the impact of IVIG dosage and infusion intervals and relating them to clinical side effects and therapeutic efficacy.

Antibody therapy (IVIG): evaluation of the use of genomics and proteomics for the study of immunomodulation therapeutics

BACKGROUND AND OBJECTIVES

Intravenous immunoglobulin (IVIG) is used for an increasingly diverse number of therapeutic applications as an immunomodulation drug. Although it has demonstrated therapeutic effectiveness, the mechanism of action of IVIG in these disorders is poorly understood; this lack of understanding complicates rational clinical application and reimbursement for 'off-label' use.

MATERIALS AND METHODS

Selected literature on the clinical use of IVIG as an immunomodulation drug is reviewed. We present a brief description of DNA microarray and protein microarray technology and the application of such technologies to the study of immune system cells. The several studies on the application of DNA microarray technology to study gene expression in response to IVIG are presented.

RESULTS

There is increasing data on the use of DNA microarray and protein microarray technology to study gene expression in immune system cells including T cells, B cells, macrophages, and leucocytes. There is less information on the effect of IVIG on gene expression in immune system cells. However, there is sufficient information available to suggest that this is a practical approach with the caveat that such work will require careful experimental design and clear definition of the normal population.

CONCLUSIONS

DNA and protein microarray assays can be used to (i) provide rational indications for the clinical use of IVIG, (ii) provide for specific analysis of raw material and end product IVIG in screening for content related to immunomodulation, and (iii) accelerate the development of next generation products which would be more focused and/or targeted therapeutics.

Intravenous immunoglobulins and haematopoietic growth factors in the prevention and treatment of neonatal sepsis: ground reality or glorified myths?

Neonatal sepsis is a significant cause of morbidity and mortality in the neonatal intensive care unit. The epidemiology of neonatal infections is complex; however, they are in large part secondary to developmentally immature host defence mechanisms. These immunodeficiencies, which are exaggerated in premature and sick neonates, include quantitative and qualitative deficits in phagocytes, complement components, cytokines and immunoglobulins. Therapies that modulate or augment host defences may attenuate the virulence of neonatal infections. In this paper, we have reviewed immunotherapies that modulate the immune system of the neonate, including intravenous immunoglobulins and myeloid haematopoietic growth factors. Future studies should focus on investigating other abnormalities of neonatal host defence and/or combined immunotherapy approaches in an attempt to circumvent the immaturity of host defence and potentially reduce both the incidence and severity of neonatal sepsis.

Reduced levels of antiinflammatory cytokines in patients with chronic widespread pain

OBJECTIVE

The term chronic widespread pain refers to a group of painful diseases of poorly understood pathophysiology. One major subgroup is fibromyalgia (FM), as defined by the criteria of the American College of Rheumatology. Among other hypotheses, a potential pathophysiologic role of cytokines in chronic widespread pain has been proposed. We undertook this study to investigate whether cytokine profiles differ in patients with chronic widespread pain and controls.

METHODS

We analyzed cytokine expression patterns in 40 patients with chronic widespread pain (26 of whom had FM), 40 age- and sex-matched healthy controls, and an additional 15 patients with chronic widespread pain who were recruited from a different center. Expression of messenger RNA (mRNA) for interleukin-2 (IL-2), IL-4, IL-8, IL-10, tumor necrosis factor alpha (TNFalpha), and transforming growth factor beta1 (TGFbeta1) in peripheral blood was analyzed using quantitative real-time polymerase chain reaction (PCR). Serum protein levels were measured by enzyme-linked immunosorbent assay.

RESULTS

We found significantly lower relative gene expression (P < 0.0001 for IL-4; P = 0.03 for IL-10) and lower levels of serum protein concentrations (P < 0.0001 for IL-4; P = 0.04 for IL-10) of the Th2 cytokines IL-4 and IL-10 in patients with chronic widespread pain than in the control group. This finding was corroborated in an additional group of 15 patients with chronic widespread pain. There were no significant differences between the groups in levels of mRNA for IL-2, IL-8, TNFalpha, or TGFbeta1. Protein data paralleled the real-time PCR results.

CONCLUSION

Chronic widespread pain is associated with a lack of antiinflammatory and analgesic Th2 cytokine activity, which may contribute to its pathogenesis.

Modulation of cytokine production by intravenous immunoglobulin in patients with enterovirus 71-associated brainstem encephalitis

BACKGROUND

Several epidemics of enterovirus 71 (EV71) infections occurred in Taiwan since 1998.

OBJECTIVES

We performed the study to determine the changes in cytokine profiles associated with administration of intravenous immunoglobulin (IVIG) in patients with EV71-associated brainstem encephalitis complicated by autonomic nervous system (ANS) dysfunction and pulmonary edema.

STUDY DESIGN

Plasma cytokine concentrations (IL-1beta, IL-6, IL-8, IFN-gamma, TNF-alpha, IL-2, IL-4, IL-5, IL-10, and IL-13) were monitored on admission and within 12-24h after administration of IVIG in a cohort of children (n=22) with virologically confirmed EV71 infection, from March 2000 through April 2004.

RESULT

Plasma levels of IFN-gamma, IL-6, IL-8, IL-10, and IL-13 levels significantly decreased in patients with pulmonary edema after administration of IVIG, P<0.05. Plasma levels of IL-6 and IL-8 were significantly decreased in patients with ANS dysregulation after administration of IVIG, P<0.05. Administration of IVIG was not associated with significant changes in plasma concentration of IL-1beta, IL-2, IL-4, IL-5 IL-10, IL-13 and TNF-alpha in patients with ANS dysregulation.

CONCLUSIONS

These findings suggest that IVIG might be considered to have a therapeutic role in EV71-associated brainstem encephalitis. A clinical trial is needed to support this hypothesis.

The role of intravenous immunoglobulin in the treatment of chronic heart failure

Chronic heart failure (HF), including both ischemic and idiopathic dilated cardiomyopathies, is accompanied by a dysregulated cytokine network characterized not only by a rise in inflammatory cytokines, but also by an inadequate elevation of anti-inflammatory mediators. This dysregulation has been implicated in the development and progression of chronic HF, and in the last decade, attempts have been made to modulate this persistent inflammation. Failure of anti-tumor necrosis factor therapy in HF has led to further interest in a more general immunomodulatory approach, directed against the inflammatory imbalance rather than one particular cytokine. Treatment with intravenous immunoglobulin (IVIg) may represent such a broad-based approach trying to restore the dysregulated cytokine network through various mechanisms such as Fc receptor blockade, neutralization of microbial antigens and superantigens and more direct anti-inflammatory effects on the cytokine network. However, although one randomized placebo-controlled study in patients with chronic HF showed that IVIg improved left ventricular ejection fraction, accompanied by anti-inflammatory net effects, IVIg had no effect in another placebo-controlled study examining the effect of this medication in recent-onset cardiomyopathy. So far, few patients have been included in clinical trials, and there is clearly a need for larger placebo-controlled mortality studies involving a diverse group of patients with regard to cause and severity of HF.

Antenatal administration of Rh-immune globulin causes significant increases in the immunomodulatory cytokines transforming growth factor-β and prostaglandin E2

BACKGROUND

Production of specific cytokines in response to administration of Rh-immune globulin (RhIG) was examined to assess the mechanism of inhibition of the anti-D production and prevention of hemolytic disease of the newborn (HDN).

STUDY DESIGN AND METHODS

Plasma levels of 17 different cytokines before and 48 hours after antenatal administration of anti-D were measured in 10 women candidates for prophylaxis with RhIG.

RESULTS

No striking changes were observed in levels of the cytokines interleukin (IL)-1 sRII, IL-12 p40, IL-16, or monocyte chemoattractant protein-1. Levels of IL-4, -5, -10, -13, and -17; macrophage inflammatory protein-1alpha; granulocyte-macrophage-colony-stimulating factor; tumor necrosis factor-beta; and interferon-gamma remained below detection levels both before and after testing. IL-1ra levels, however, showed a slight to moderate decrease in 7 of 10 women after RhIG administration. In contrast, levels of TGF-beta1 increased more than 1.3-fold in 7 of 10 women and more than 2-fold in 4 of 10 women; in 1 instance the increase was more than 5-fold and this woman also had a significant increase in TGF-beta2. In addition to TGF-beta, 5 of 10 women had a modest increase (>1.5-fold) in prostaglandin E2 (PGE2). Analyses of the combined results of the 10 women showed that increases in both TGF-beta1 and PGE2 after RhIG were significant.

CONCLUSION

These results indicate that RhIG prophylaxis can induce higher than baseline levels of two strongly immunomodulatory cytokines, TGF-beta and PGE2. These findings represent one possible mechanism for the inhibition of the primary immune response to the D antigen in women receiving RhIG prophylaxis for prevention of HDN.

The efficiency of intraperitoneal high-dose immunoglobulin in experimental nephrotic syndrome

Although it has been reported that high-dose immunoglobulin has beneficial effects in chronic glomerulonephritis, it is not known whether it is effective in the treatment of idiopathic nephrotic syndrome. We have investigated the effects of intraperitoneal immunoglobulin in adriamycin-induced nephrotic syndrome. Adriamycin (2 mg kg(-1) per dose) was given intravenously to sixteen Wistar albino rats (eight control and eight treatment rats) on day 1 and at week 3. At week 5 intraperitoneal immunoglobulin (1 g kg(-1) per dose) was given to the treatment group on two consecutive days whereas the control group received intraperitoneal saline solution. In both treatment and control groups urinary protein excretion was significantly elevated after administration of adriamycin (P=0.018). Urinary protein excretion, serum albumin, and triglyceride levels in the two groups were not significantly different after 5, 8, 12, and 16 weeks. Serum creatinine levels were higher and creatinine clearance was significantly lower in the control group in week 16 (P=0.001 and P=0.049, respectively). Glomerular sclerosis index was significantly lower in the treatment group (P=0.012). Although intraperitoneal high-dose immunoglobulin did not reverse biochemical results, it is encouraging that glomerular sclerosis index was significantly lower in the treatment group.

Modulating Effects of Intravenous Immunoglobulins on Serum Cytokine Levels in Patients with Primary Hypogammaglobulinemia

BACKGROUND

Intravenous immunoglobulins (IVIG) have usually been administered for replacement therapy of humoral immunodeficiencies, but their use in treating other disorders with an immune pathogenesis is increasing. The exact mechanism of action by which IVIG are of benefit in such diseases is complex and only partly understood. One of the proposed mechanisms of action is the modulation of cytokine release.

METHODS

We selected 29 patients with primary hypogammaglobulinemia (common variable immunodeficiency), receiving long-term substitutive therapy with IVIG, and 14 healthy blood donors as a control group. Blood samples were then taken before and 1 hour after finishing the IVIG infusion. Only one blood sample was obtained from the healthy controls. The cytokines studied were interleukin (IL)-1 beta, IL-1 receptor antagonist (IL-1Ra), IL-2, IL-6, IL-8, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma.

RESULTS

Patients with primary hypogammaglobulinemia showed significantly higher serum levels of IL-6, IL-8, IL-1Ra, and TNF alpha than healthy controls. IVIG infusion significantly increased serum concentration levels of IL-6, IL-8, IL-1Ra, and TNF alpha. No significant variation was observed in serum levels of IL-beta, IFN gamma, or IL-2 after IVIG infusion. Age, IVIG commercial preparation, and IVIG dose did not influence cytokine serum levels. Moreover, a significant correlation was observed between serum level variations of IL-1Ra and TNF alpha, as well as an associative trend between maximum changes in IL-6 and IL-8 concentrations.

CONCLUSIONS

IVIG administration significantly alters the serum pattern of selected cytokines, which might explain, at least in part, the mechanism of action of IVIG in autoimmune or inflammatory disorders.

The use of intravenous immunoglobulin in the treatment of autoimmune neuromuscular diseases: evidence-based indications and safety profile

Intravenous immunoglobulin (i.v.Ig) has multiple actions on the immunoregulatory network that operate in concert with each other. For each autoimmune neuromuscular disease, however, there is a predominant mechanism of action that relates to the underlying immunopathogenetic cause of the respective disorder. The best understood actions of i.v.Ig include the following: (a) modulation of pathogenic autoantibodies, an effect relevant in myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS), Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), and stiff-person syndrome (SPS); (b) inhibition of complement activation and interception of membranolytic attack complex (MAC) formation, an action relevant to the complement-mediated mechanisms involved in GBS, CIDP, MG, and dermatomyositis (DM); (c) modulation of the inhibitory or activation Fc receptors on macrophages invading targeted tissues in nerve and muscle, as seen in CIDP, GBS, and inflammatory myopathies; (d) down-regulation of pathogenic cytokines and adhesion molecules; (e) suppression of T-cell functions; and (f) interference with antigen recognition. Controlled clinical trials have shown that i.v.Ig is effective as first-line therapy in patients with GBS, CIDP, and multifocal motor neuropathy (MMN), and as second-line therapy in DM, MG, LEMS, and SPS. In paraproteinemic IgM anti-MAG (myelin-associated glycoprotein) demyelinating polyneuropathies and inclusion body myositis (IBM), the benefit is variable, marginal, and not statistically significant. i.v.Ig has a remarkably good safety record for long-term administration, however, the following side effects have been observed: mild, infusion-rate-related reactions, such as headaches, myalgia, or fever; moderate but inconsequential events, such as aseptic meningitis and skin rash; and severe, but rare, complications, such as thromboembolic events and renal tubular necrosis. Future studies are needed to (a) find the appropriate dose and frequency of infusions that maintain a response; (b) address pharmacoeconomics, comparing the high cost of i.v.Ig to the cost of the other therapies, which, although less expensive, cause significantly more long-term side effects; (c) determine why some patients respond better than others; and (d) examine the merits of combining i.v.Ig with other immunosuppressive drugs.

Effets immunomodulateurs des immunoglobulines intraveineuses

Intravenous immunoglobulins (IVIg) are therapeutic preparations of normal human IgG obtained from pools of more than 1000 healthy blood donors. They are currently used in the treatment of a wide range of auto-immune diseases, whether associated with auto-antibodies or auto-reactive T lymphocytes, as well as in the treatment of systemic inflammatory diseases. Several mechanisms of action have been identified during the last 20 years, including: (i) modulation of Fc receptors expression on leukocytes and endothelial cells; (ii) interaction with complement proteins; (iii) modulation of cytokines and chemokines synthesis and release; (iv) modulation of cell proliferation and apoptosis; (v) remyelinisation; (vi) neutralisation of circulating autoantibodies; (vii) selection of repertoires of B and T lymphocytes; (viii) interaction with other cell-surface molecules on lymphocytes and monocytes; (ix) corticosteroid sparing. These mechanisms of action are multiple and often intricate. However, they are still little known and further investigations are warranted.

Can polyclonal intravenous immunoglobulin limit cytokine mediated cerebral damage and chronic lung disease in preterm infants?

Recent evidence suggests that inflammatory cytokines may play an important role in cerebral and pulmonary injury, especially in preterm infants. Immunomodulatory agents may help to limit such injury by reducing inflammation. Immunoglobulin has multiple anti-inflammatory properties and can modulate the inflammatory cytokine response. New evidence is required to test the hypotheses that prophylaxis or treatment with intravenous immunoglobulin may limit such inflammatory damage.

Immunotherapy for autoimmune and inflammatory renal diseases

Immune-mediated renal disease (IMRD) accounts for 20 - 30% of the cases of end stage renal failure. It frequently occurs in the context of multi-system autoimmune disorders, including systemic lupus erythematosus (SLE) and primary systemic vasculitis. Current therapies are partially effective and comprise the combination of steroids with an immunosuppressive, such as cyclophosphamide. Their toxicity contributes to the morbidity and mortality of these disorders, and long-term treatment is necessary to prevent relapse. There is a clear need for better-targeted, more effective and less toxic therapy. Advances in our understanding of the immunopathogenesis of inflammatory autoimmune renal disease have identified potential targets for newer agents and have improved the monitoring of therapeutic responses. Recent experience with newer therapies in IMRD is reviewed. This has typically involved small, non-randomised, open-label trials and has addressed reversible features of disease activity. Larger, randomised comparisons to standard therapy are needed along with assessment of long-term efficacy and safety.

Changes in serum macrophage-related factors in patients with chronic inflammatory demyelinating polyneuropathy caused by intravenous immunoglobulin therapy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a slowly progressive or recurrent neuropathy accompanied by infiltration of macrophages in the peripheral nerves. Macrophage colony-stimulating factor (M-CSF) and monocyte chemoattractant protein-1 (MCP-1) are a macrophage-related cytokine and chemokine, respectively. Although, intravenous immunoglobulin (IVIg) infusion therapy has been used for treating CIDP patients, not all CIDP patients have responded to IVIg infusion therapy. To determine the mechanisms of the action of IVIg, we examined serum M-CSF and MCP-1 levels during and after IVIg infusion therapy in 19 CIDP patients treated with IVIg (0.4 g/kg/day for 5 days). Ten of the 19 patients (52.6%) responded to IVIg therapy. Both M-CSF and MCP-1 concentrations in IVIg responders were significantly higher on day 1 postinfusion than those in nonresponders, but decreased to their pretreatment values on day 5 postinfusion. The results suggest that immunomodulation through M-CSF and MCP-1 is involved in the mechanisms underlying the effect of IVIg infusion therapy in CIDP patients.

The Norwegian Plasma Fractionation Project--a 12 year clinical and economic success story

The establishment of the Norwegian Fractionation Project (Project) was of major importance in preserving national self-sufficiency when plasma, cryoprecipitate and small batch factor IX-concentrates were replaced by virus inactivated products in the last part of the 1980s. Fractionation was performed abroad by contract with Octapharma after tenders on the European market. All Norwegian blood banks (>50) participated in the Project. Total yearly production was 50-60 tons of mainly recovered plasma. From 1993 solvent detergent (SD) treated plasma has replaced other plasma for transfusion. The blood banks paid for the fractionation and/or viral inactivation process, while the plasma remained the property of the blood banks and the final products were returned to the blood banks. The Project sold surplus products to other Norwegian blood banks and the majority of the coagulation factor concentrates to The Institute of Haemophilia and Rikshospitalet University Hospital. Both plasma and blood bank quality was improved by the Project. Clinical experience with the products has been satisfactory and self-sufficiency has been achieved for all major plasma proteins and SD plasma, but a surplus exceeding 3 years consumption of albumin has accumulated due to decreasing clinical use.The Project has secured high yields of the fractionated products and the net income from the produced products is NOK 1115 (140 Euros or US dollars) per litre plasma. An increasing surplus of albumin and the possibility of significant sales abroad of currently not fractionated IVIgG, could lead to a reorganisation of the Project from that of a co-ordinator to a national plasma handling unit. This unit could buy the plasma from the blood banks and have the plasma fractionated by contract after tender, before selling the products back for cost recovery. The small blood banks could produce plasma for products for the Norwegian market, while surplus products from the larger blood banks which are certified for delivery of plasma for fractionation of products to be consumed in the European Community, could be sold on the international market.

Mechanisms of intravenous immunoglobulin action in the treatment of autoimmune disorders

Intravenous immunoglobulins (IVIg) are therapeutic preparations of normal human immunoglobulin (Ig) G obtained from pools of blood from more than 1000 healthy donors, and exert immunomodulatory effects in autoantibody-mediated and T-cell-mediated autoimmune disorders and systemic inflammatory diseases. IVIg mechanisms of action in autoimmune diseases have been extensively analysed during the last 15 years and include the following: (i) interaction of the IgG Fc fragment with Fc receptors on leucocytes and endothelial cells; (ii) interaction of infused IgG with complement proteins; (iii) monocyte and lymphocyte modulation of synthesis and release of cytokines and cytokine antagonists; (iv) modulation of cell proliferation and reparation; (v) neutralisation of circulating autoantibodies; (vi) selection of immune repertoires; and (vii) interaction with other cell-surface molecules on T and B lymphocytes.

Mechanism of action of IVIG in ITP

IVIG is prepared from large pools of plasma from healthy donors and the IgG is present predominantly in monomeric form. It was first reported in 1981 by Dr. Paul Imbach that high doses of IVIG promote fast recovery of ITP in children. Despite extensive clinical use in a variety of autoimmune and inflammatory states, the mechanism of action of IVIG remains as yet incompletely understood. Several theories have been proposed to explain how administration of IVIG to individuals with ITP increases the platelet count. Following is an overview of some of the major theories.

Pemphigus vulgaris: the role of IL-1 and IL-1 receptor antagonist in pathogenesis and effects of intravenous immunoglobulin on their production

Intravenous immunoglobulin (IVIG) is increasingly being used for the treatment of autoimmune diseases. In the present report, the role of IVIG on in vivo and in vitro production of IL-1 and IL-1 receptor antagonist (Ra) was studied in patients with pemphigus vulgaris (PV). Serum samples from 20 untreated patients with active PV prior to initiation of systemic therapy, 20 patients receiving IVIG treatment, 20 patients in clinical remission after conventional therapy, and 20 normal human controls were studied to determine the serum levels of IL-1alpha, IL-1beta, and IL-1Ra. The in vitro production of these cytokines was measured in the culture supernatant of peripheral blood mononuclear cells (PBMC) from 10 PV patients immediately before and after IVIG therapy and from age and sex-matched 10 healthy donors simultaneously. Elevated levels of IL-1alpha and IL-1beta were detected (i) in the serum of untreated PV patients with active disease prior to systemic therapy and (ii) before IVIG infusions in patients receiving IVIG therapy. These increased levels are statistically significant when compared to the levels in healthy controls (P < 0.01). A marked reduction of IL-1alpha and IL-1beta was detected (i) in the serum of patients in prolonged clinical remission and (ii) immediately after IVIG infusion in those patients on IVIG therapy. Increased level of IL-1Ra was detected in PV patients in prolonged clinical remission and after IVIG infusion in those receiving IVIG therapy. These differences were statistically significant when compared to the levels in normal controls and to the levels in the sera of patients with active disease (P < 0.01) or just before the beginning of IVIG infusion (P < 0.01). Similar differences in the levels of IL-1alpha, IL-1beta, and IL-1Ra were found in the culture supernatant of PBMC isolated from the PV patients pre and post IVIG therapy. These observations suggests that, compared to normal controls, patients with active PV have reversed levels of IL-1alpha, IL-1beta, and IL-1Ra. IVIG therapy may down-regulate production of IL-1alpha and IL-1beta and enhance production of IL-1Ra, in vivo and in vitro. This might be one of the important mechanisms by which IVIG produces its early therapeutic effects in pemphigus vulgaris.

Immunomodulating therapy with intravenous immunoglobulin in patients with chronic heart failure

BACKGROUND

Congestive heart failure (CHF) is characterized by enhanced immune activation, and immune-mediated mechanisms may play a pathogenic role in this disorder. Based on the immunomodulatory effects of intravenous immunoglobulin (IVIG), we hypothesized that IVIG could downregulate inflammatory responses in CHF patients and have potential beneficial effects on the left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

Forty patients with chronic symptomatic CHF and LVEF of <40%, stratified according to cause (ie, ischemic and idiopathic dilated cardiomyopathy), were randomized in a double-blind fashion to receive therapy with IVIG or placebo for a total period of 26 weeks. Our main findings were that (1) IVIG, but not placebo, induced a marked rise in plasma levels of the anti-inflammatory mediators interleukin (IL)-10, IL-1 receptor antagonist, and soluble tumor necrosis factor receptors; (2) significantly correlated with these anti-inflammatory effects, IVIG, but not placebo, induced a significant increase in LVEF from 26+/-2% to 31+/-3% (P:<0.01), and this was found independent of the cause of heart failure; and (3) N-terminal pro-atrial natriuretic peptide decreased significantly after induction therapy and continued to decrease toward the end of study during IVIG therapy (P:<0.001) but remained unchanged during placebo.

CONCLUSIONS

We demonstrated an IVIG-induced change in the balance between inflammatory and anti-inflammatory cytokines that favored an anti-inflammatory net effect in CHF. This effect was significantly correlated with an improvement in LVEF, suggesting a potential for immunomodulating therapy in addition to optimal conventional cardiovascular treatment regimens in CHF patients.

Increased levels of biochemical markers of bone turnover in relation to persistent immune activation in common variable immunodeficiency

BACKGROUND

Based on the involvement of cytokines and growth factors in bone homeostasis, we hypothesised that patients with common variable immunodeficiency (CVI), characterised by persistent immune activation in vivo, may have disturbed bone metabolism as evaluated by biochemical markers of bone turnover.

MATERIALS AND METHODS

Serum levels of tumour necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), bone-specific alkaline phosphatase (B-ALP), osteocalcin, carboxyterminal crosslinking telopeptide of type I collagen (CTX-I), insulin-like growth factor (IGF)-I and IGF binding protein-3 (IGFBP-3) were measured in 25 patients with CVI and compared to 25 age- and sex-matched healthy controls.

RESULTS

Patients with CVI had significantly higher serum levels of CTX-I and B-ALP, and significantly lower serum levels of IGF-I and IGFBP-3 compared to controls as shown in cross-sectional, and as for B-ALP and CTX-I, also during longitudinal testing. No differences were observed for osteocalcin between the two groups. The elevated B-ALP and decreased IGF-I and IGFBP-3 levels were most pronounced in a subgroup of CVI patients characterised by persistent activation of proinflammatory cytokines in vivo. Raised B-ALP and decreased IGF-I and IGFBP-3 were also significantly correlated with enhanced IL-6 and TNF-alpha levels in these patients.

CONCLUSIONS

The present study suggests that persistent immune activation in vivo, with raised levels of proinflammatory cytokines, may be related to disturbed bone homeostasis in CVI patients, further supporting an interaction between immune related mediators and bone metabolism in humans.

Intravenous immunoglobulin in the treatment of autoimmune neuromuscular diseases: present status and practical therapeutic guidelines

This review summarizes the current status of intravenous immunoglobulin (IVIg) in the treatment of autoimmune neuromuscular disorders and the possible mechanisms of action of the drug based on work in vivo, in vitro, and in animal models. Supply of idiotypic antibodies, suppression of antibody production, or acceleration of catabolism of immunoglobulin G (IgG) are relevant in explaining the efficacy of IVIg in myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS), and antibody-mediated neuropathies. Suppression of pathogenic cytokines has putative relevance in inflammatory myopathies and demyelinating neuropathies. Inhibition of complement binding and prevention of membranolytic attack complex (MAC) formation are relevant in dermatomyositis (DM), Guillain-Barré syndrome (GBS), and MG. Modulation of Fc receptors or T-cell function is relevant in chronic inflammatory demyelinating polyneuropathy (CIDP), GBS, and inflammatory myopathies. The clinical efficacy of IVIg, based on controlled clinical trials conducted in patients with GBS, CIDP, multifocal motor neuropathy (MMN), DM, MG, LEMS, paraproteinemic IgM anti-myelin-associated glycoprotein (anti-MAG) demyelinating polyneuropathies, and inclusion body myositis is summarized and practical issues related to each disorder are addressed. The present role of IVIg therapy in other disorders based on small controlled or uncontrolled trials is also summarized. Finally, safety issues, risk factors, adverse reactions, spurious results or serological tests, and practical guidelines associated with the administration of IVIg in the treatment of neuromuscular disorders are presented.