Idiopathic thrombocytopenic purpura (ITP): immunomodulation by intravenous immunoglobulin (IVIg)

Immunomodulatory and anti-inflammatory properties of immunoglobulin G antibodies

Antibodies provide an essential layer of protection from infection and reinfection with microbial pathogens. An impaired ability to produce antibodies results in immunodeficiency and necessitates the constant substitution with pooled serum antibodies from healthy donors. Among the five antibody isotypes in humans and mice, immunoglobulin G (IgG) antibodies are the most potent anti-microbial antibody isotype due to their long half-life, their ability to penetrate almost all tissues and due to their ability to trigger a wide variety of effector functions. Of note, individuals suffering from IgG deficiency frequently produce self-reactive antibodies, suggesting that a normal serum IgG level also may contribute to maintaining self-tolerance. Indeed, the substitution of immunodeficient patients with pooled serum IgG fractions from healthy donors, also referred to as intravenous immunoglobulin G (IVIg) therapy, not only protects the patient from infection but also diminishes autoantibody induced pathology, providing more direct evidence that IgG antibodies play an active role in maintaining tolerance during the steady state and during resolution of inflammation. The aim of this review is to discuss different conceptual models that may explain how serum IgG or IVIg can contribute to maintaining a balanced immune response. We will focus on pathways depending on the IgG fragment crystallizable (Fc) as pre-clinical data in various mouse model systems as well as human clinical data have demonstrated that the IgG Fc-domain recapitulates the ability of intact IVIg with respect to its ability to trigger resolution of inflammation. We will further discuss how the findings already have or are in the process of being translated to novel therapeutic approaches to substitute IVIg in treating autoimmune inflammation.

How I treat thrombocytopenia in pregnancy

ABSTRACT

Thrombocytopenia is a common hematologic abnormality in pregnancy, encountered in ∼10% of pregnancies. There are many possible causes, ranging from benign conditions that do not require intervention to life-threatening disorders necessitating urgent recognition and treatment. Although thrombocytopenia may be an inherited condition or predate pregnancy, most commonly it is a new diagnosis. Identifying the responsible mechanism and predicting its course is made challenging by the tremendous overlap of clinical features and laboratory data between normal pregnancy and the many potential causes of thrombocytopenia. Multidisciplinary collaboration between hematology, obstetrics, and anesthesia and shared decision-making with the involved patient is encouraged to enhance diagnostic clarity and develop an optimized treatment regimen, with careful consideration of management of labor and delivery and the potential fetal impact of maternal thrombocytopenia and any proposed therapeutic intervention. In this review, we outline a diagnostic approach to pregnant patients with thrombocytopenia, highlighting the subtle differences in presentation, physical examination, clinical course, and laboratory abnormalities that can be applied to focus the differential. Four clinical scenarios are presented to highlight the pathophysiology and treatment of the most common causes of thrombocytopenia in pregnancy: gestational thrombocytopenia, preeclampsia, and immune thrombocytopenia.

Effects of the immunoglobulin/histamine complex on panic disorder concurrent with chronic spontaneous urticaria: a case report

BACKGROUND

Panic disorder and panic attacks are two of the most common problems in psychiatry. A psychoimmunological correlation between allergic diseases and panic disorder has been strongly suggested. Histamine H1 receptor antagonists have been suggested as alternative drugs for the treatment of panic disorder. Chronic spontaneous urticaria (CSU) and panic disorder improved simultaneously with selective serotonin reuptake inhibitor antidepressants. Panic disorder has also been treated with the antihistamine chlorpheniramine. The immunoglobulin/histamine complex is a histamine-fixed immunoglobulin preparation that was reported to be effective in treating CSU. This case report describes the successful treatment of a patient with concomitant panic disorder and CSU for 23 years using immunoglobulin/histamine complex therapy.

CASE PRESENTATION

This report describes a 52-year-old female Korean patient who suffered from CSU with panic disorder for 23 years. Basic allergy tests (blood tests and skin prick tests) were conducted before and after treatment for the evaluation of allergic conditions. A multiple allergosorbent test (MAST) for the detection of allergen-specific IgE levels was also performed. The clinical severity of CSU was evaluated using the urticaria severity score system. Diagnostic interviews systematically assessed the diagnostic criteria outlined by the DSM-V, and the patient was evaluated before, during and after treatment using the Beck Depression Inventory (BDI-2) for depression, the State-Trait Anxiety Inventory (STAI) for anxiety and the Beck Hopelessness Score (BHS) for hopelessness. The patient received 2 ml of Histobulin™ (12 mg human immunoglobulin/0.15 µg histamine complex) once a week by subcutaneous injection for the treatment of CSU. Initial improvement of CSU was achieved after the third injection. After the twenty-seventh injection of Histobulin™, she showed no symptoms or signs and ceased allergic medication use. With the remission of CSU, allergic rhinitis was also completely resolved. The frequency of the common cold was significantly decreased during and after treatment. The medication frequency and development of clinical manifestations of panic disorder changed in parallel with the clinical severity of CSU. Moreover, the patient exhibited no clinical manifestations and ceased medication for panic disorder and sleeping pills for insomnia simultaneously with the remission of CSU. In the psychological evaluation, the BDI, STAI and BHS scores improved accordingly.

CONCLUSIONS

The immunoglobulin/histamine complex was effective in treating CSU and concomitant panic disorder in this patient and could be effective in treating some types of panic disorder. Considering the mechanisms of action of histamine and the immunoglobulin/histamine complex together with the patient's clinical progress, histamine seemed to be related to panic disorder in this case. The concept of histamine-mediated syndromes, including allergies and psychiatric disorders, shows that a wider disease identity may be needed. Further studies on the immunopathogenesis of panic disorder and the mechanisms of action of the immunoglobulin/histamine complex are necessary.

Immunotherapy using Histobulin™ in psoriasis: A case report

There is no cure for psoriasis. A psoriasis patient was treated with Histobulin™. The patient's clinical symptoms and signs disappeared after the eighth injection and did not recur for more than 18 months. Histobulin™ was effective in the treatment of psoriasis and is suggested as a curative therapeutic for psoriasis.

There is no cure for psoriasis, and early treatment is recommended to improve skin manifestations and systemic inflammation, which can lead to comorbidities in various organs. Histobulin™ was effective and induced remission in a psoriasis patient.

Induction of remission in chronic urticaria by immunotherapy using immunoglobulin/histamine complex (Histobulin™): a case report

BACKGROUND

Symptom control is a major concern in chronic urticaria. Histobulin™ is a histamine/immunoglobulin complex that has been approved for allergic rhinitis, bronchial asthma and chronic urticaria in some countries. Not only has the immunoglobulin/histamine complex been reported to be effective in allergic diseases, including chronic urticaria, but recently, the possibility of remission induction in chronic urticaria by the immunoglobulin/histamine complex has been reported.

CASE PRESENTATION

Histobulin™ was administered until remission was induced instead of fixing the number of administrations in four cases of chronic urticaria. Two patients showed an early response and finished treatment with 12 injections of Histobulin™, and the other two patients showed a late response and were injected 43 and 46 times. Remission was induced successfully in all four cases.

CONCLUSIONS

Histobulin™ is not only effective but also induces remission in CSU. The Histobulin™ therapy protocol in CSU may be better if the treatment is continued until remission is achieved. Based on the responses of the patients, early responders and late responders were present. The progression of the disease during treatment consisted of a slow improvement phase and a rapid improvement phase. Uniquely, the appropriate allergy laboratory results, including blood eosinophil fraction, total IgE and eosinophil cationic protein level, were normal in all 4 cases. Further studies concerning the mechanisms of Histobulin™ may be needed.

Combination Oral Prednisone and Intravenous Immunoglobulin in the Treatment of Scleromyxedema

Background:

Scleromyxedema is a clinical variant of the rare disease papular mucinosis that has both cutaneous and systemic manifestations. Treatment options are numerous and tend to be associated with serious potential side effects and frequent relapse.

Objective:

We report a case of scleromyxedema treated with low-dose oral prednisone and intravenous immunoglobulin (IVIg). This is followed by a review of the literature.

Conclusion:

IVIg is being used for a growing number of inflammatory and immune disorders. It is being increasingly reported as a successful treatment for scleromyxedema. Although our patient succumbed to the disease, combination therapy with prednisone and IVIg provided temporary symptomatic, laboratory, and clinical improvement of the condition. Optimization of this therapeutic strategy is thus indicated for the management of scleromyxedema.

Three major uncertainties in the antibody therapy of cancer

Antibodies against surface molecules of human tumors are now frequently administered in combination with strong chemotherapy, increasing therapeutic efficacy but making the task of elucidating immunological events more difficult. Experiments on genetically manipulated mice indicate that antibody efficacy is greatest when IgG antibody coating tumor cells is engaged by the Fcγ-receptors of effector cells, chiefly the monocyte/macrophage lineage. Evidence suggests lesser roles for NK cells, neutrophils, receptor-mediated cytotoxicity and complement-mediated cytotoxicity. The classical mode of killing employed by macrophages is phagocytosis, but much has to be learned about optimally activating macrophages for this task, and about any other modes of cytotoxicity used. There is renewed interest in antigenic modulation, which implies removal of therapeutic antibody linked with antigen from target-cell surfaces. It is now apparent that this removal of immune complexes can be achieved either by internalization by the target cell, or by transfer of the complexes to another cell by trogocytosis. In trials, anti-idiotype antibodies surprisingly proved therapeutically more effective than anti-CD20, despite anti-idiotype being more effectively removed from target-cell surfaces by antigenic modulation. This anomalous result might reflect the fact that persistence of anti-CD20 immune complexes in large amounts induces serious effector modulation, which paralyzes macrophage attacks on antibody-coated cells. The case for effector modulation is argued by analogy with the therapeutic suppression of autoimmune inflammation by effector modulation, achieved by infusion either of normal IgG in large amounts, or of anti-red cell IgG in relatively small amounts.

Cationized IVIg as a potential substitute to IVIg for the treatment of experimental immune thrombocytopenia

In this study, we evaluated the possibility of using cationized IVIg (cIVIg) instead of IVIg as a more effective therapy for the treatment of experimental immune thrombocytopenia in mice. The pharmacokinetics (PK) and biodistribution of cIVIg and IVIg in mice were compared. cIVIg displayed a shorter plasma half-life and an increased organ uptake in both the spleen and liver compared to IVIg, suggesting that cIVIg could be more potent than IVIg to prevent platelet clearance in a mouse model of thrombocytopenia. However, although the biodistribution of cIVIg in the spleen and liver was improved, its ability to prevent platelet clearance in mice remained similar to that of IVIg. Altogether, our data demonstrate the possibility of using chemical cationization of IVIg preparations to increase organ uptake, and also highlight the challenges of developing effective substitutes to IVIg.

Platelets in inflammation and immune modulations: functions beyond hemostasis

Platelets play central roles for maintaining the homeostasis of the blood coagulation. As they are also involved in immune responses and host defenses, increasing evidences have suggested that platelets exert other roles beyond their well-recognized function in preventing bleeding. This review is focused on inflammation, allergy and immune modulations of platelets. Platelets conduct immunoregulation through secretion of functional mediators, interaction with various immune cells, endothelial cells and beneficial for the leukocyte infiltration to inflamed/allergic tissues. In these regulations, the leukocytes are influenced by and receiving the signals from platelets. In contrast, rare attentions were focused on platelet regulations by immune system. An intriguingly example in the intravenous immunoglobulin (IVIg) treatment is discussed, in which dendritic cells exert anti-inflammatory effect through platelets. This further suggests that coagulant and immune systems are tightly associated rather than separate entities. The cross-talks between these two systems implicate that platelet therapy may have application beyond thrombosis, and immune interventions may have potentials to treat thrombosis diseases.

Tolerability and safety of the intravenous immunoglobulin Octagam: a 10-year prospective observational study

PURPOSE

Following the approval of Octagam in 1995, an open prospective observational cohort study has been initiated to observe the tolerability of the intravenous immunoglobulin Octagam. This study aimed to evaluate the long-term safety profile of Octagam in daily use in the treatment of various primary (PID) and secondary (SID) immunodeficiencies and autoimmune diseases (AID).

METHODS

Within a time period of 10 years, data were collected in 310 study sites. The treating physicians documented patient characteristics, treatment parameters and the occurrence of an adverse drug reaction (ADR) by using detailed case record forms (CRF).

RESULTS

A total of 6357 patients of all ages received 92 958 infusions of Octagam. ADR occurred in 4.2% of the patients and in 0.35% of all infusions. Most of them (94.8%) were classified as nonserious, the majority (90.2%) were of mild or moderate intensity. The ADR frequency differed slightly between the indication groups, for example in PID patients ADR occurred in 8.3% of patients and 0.5% of infusions, in SID patients in 5.0% of patients and 0.62% of infusions. Rigors were reported most frequently, followed by fever, headache, nausea and flush. The ADR symptoms differed between the indication groups, rigors were predominantly described in SID patients, headache in PID and AID patients including idiopathic thrombocytopenic purpura (ITP). A relation between the ADR frequency and elevated infusion rates or high dosages was not detected.

CONCLUSIONS

This unique 10-year observational study demonstrates that Octagam is well tolerated in routine clinical use with an overall ADR frequency of 0.35%.

Intravenous immunoglobulin therapy affects T regulatory cells by increasing their suppressive function

Intravenous Ig therapy (IVIg) is reported to be a useful regimen in treating autoimmune diseases. In this study, we asked whether IVIg (in vitro) could increase the expression of TGF-beta, IL-10, and the transcription factor FoxP3 in T regulatory (Treg) cells, and the idea that IVIg could enhance suppressive properties of these cells. CD4(+) T cells from 12 healthy individuals were cultured in the presence or absence of IVIg vs human control IgG during 16, 24, and 36 h. Using FACS analysis and gating on CD4(+)CD25(high) Treg cells, we assessed the expression of intracellular TGF-beta, IL-10, and FoxP3. In addition, the production of TNF-alpha by stimulated CD4(+) T cells alone or in culture with CD25(+) by itself or together with IVIg was also assessed. The presence of IVIg with Treg cells in culture significantly increased the intracellular expression of TGF-beta (17.7 +/- 8.5% vs 29.8 +/- 13%; p = 0.02), IL-10 (20.7 +/- 4.7% vs 34.2 +/- 5.2%; p = 0.008) and FoxP3 (20.8 +/- 5.2% vs 33.7 +/- 5.9%; p = 0.0006) when compared with cells cultured alone or with control human IgG. The suppressive effect of CD4(+)CD25(+) T cells presented as the decrease of TNF-alpha production by stimulated CD4(+)CD25(-) (effector T cells) was further increased by adding IVIg to cell culture. We hereby demonstrate an additional mechanism by which IVIg could maintain self-tolerance and decrease immune-mediated inflammation.

Combination oral prednisone and intravenous immunoglobulin in the treatment of scleromyxedema

BACKGROUND

Scleromyxedema is a clinical variant of the rare disease papular mucinosis that has both cutaneous and systemic manifestations. Treatment options are numerous and tend to be associated with serious potential side effects and frequent relapse.

OBJECTIVE

We report a case of scleromyxedema treated with low-dose oral prednisone and intravenous immunoglobulin (IVIg). This is followed by a review of the literature.

CONCLUSION

IVIg is being used for a growing number of inflammatory and immune disorders. It is being increasingly reported as a successful treatment for scleromyxedema. Although our patient succumbed to the disease, combination therapy with prednisone and IVIg provided temporary symptomatic, laboratory, and clinical improvement of the condition. Optimization of this therapeutic strategy is thus indicated for the management of scleromyxedema.

Treatment of Sydenham's chorea with intravenous immunoglobulin, plasma exchange, or prednisone

Sydenham's chorea has been established as a postinfectious autoimmune neuropsychiatric disorder. Corticosteroids have been used to treat patients with severe disease but are not always effective, and relapses are frequent after cessation. Eighteen subjects were entered into this randomized-entry controlled trial designed to determine if intravenous immunoglobulin or plasma exchange would be superior to prednisone in decreasing the severity of chorea. Mean chorea severity for the entire group was significantly lower at the 1-month follow-up evaluation (overall 48% improvement). Although the between-group differences were not statistically significant, clinical improvements appeared to be more rapid and robust in the intravenous immunoglobulin and plasma exchange groups than in the prednisone group (mean chorea severity scores decreased by 72% in the intravenous immunoglobulin group, 50% in the plasma exchange group, and 29% in the prednisone group). Larger studies are required to confirm these clinical observations and to determine if these treatments are cost-effective for this disorder.

Is antibody therapy of tumor compromised by infusion-related reactions?

Evidence suggests that amelioration of childhood immune thrombocytopenic purpura and some other autoimmune states by intravenous normal IgG is due to the following chain of events: (1) cross-linking of Fcgamma-receptors on blood effector cells; (2) release of mediators from these cells, often yielding an infusion-related reaction; (3) mediator-induced development of a cytokine field characterized by a mutually stabilizing Th2 polarization of CD4 T lymphocytes and alternative activation of macrophages; (4) selective quiescence of these macrophages towards targets coated with IgG autoantibody, due to increased expression of the macrophage Fcgamma-receptor IIB. In this paper it is postulated that in the field of antibody therapy of tumor, an undesirable delayed or absent subsidence of antibody-coated tumor is due to immunomodulation of the same type as yields amelioration of autoimmunity, and arising from a similar chain of events. If the postulate is correct the chain could usefully be broken at the level of mediator action, possibly by blocking that increased synthesis of prostaglandin E(2) which is catalyzed by the enzyme cyclooxygenase-2.

Immunoglobulin for rheumatic diseases in the twenty-first century: take it or leave it?

There is no simple answer to the question: intravenous immunoglobulin-take it or leave it? A thorough review of the current data on mechanisms of action, efficacy, and safety of intravenous immunoglobulins in rheumatic diseases demonstrates that the answer depends on the disease and the patients involved.

Intravenous immunoglobulin protects against experimental thrombotic microangiopathy

BACKGROUND

Intravenous immunoglobulin (IVIG) has been utilized in several forms of vasculitis and has many potential mechanisms of action, including the inhibition of C3 activation. We have previously demonstrated that IVIG can reduce glomerular injury in a model of membranous nephropathy mediated by C5b-9 [1]. C5b-9 has also been shown to mediate the thrombotic microangiopathy (TMA) induced by antibody to glomerular endothelial cells leading to a hemolytic uremic syndrome-type lesion [2].

METHODS

To test the hypothesis that IVIG might be effective in treating antibody-induced TMA, male uninephrectomized rats underwent right renal artery perfusion with goat anti-rat glomerular endothelial cell (GEN) antibody (20 mg/kg). Sheep IgG (200 mg/kg) was administered either 30 minutes before the renal artery perfusion (group I, N = 6) or 30 minutes postperfusion (group II, N = 9). A third control group received phosphate-buffered saline (PBS; group III, N = 12). A survival biopsy was performed at 15 minutes, and the animals were sacrificed on day 2.

RESULTS

There were no significant differences in proteinuria or hematocrit between the groups. Animals pretreated with IVIG had significantly improved survival and renal function, which was associated with a decrease in glomerular C3 deposition. The protective effect of IVIG was abolished if the administration was delayed 30 minutes after perfusion.

CONCLUSIONS

IVIG is effective in reducing injury in experimental TMA only if given prophylactically. The effect is mediated by inhibition of local intraglomerular complement activation.

Mechanisms of immunomodulatory action of intravenous immunoglobulin in autoimmune and systemic inflammatory diseases

Pooled therapeutic intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune and systemic inflammatory diseases. The lack of a clear understanding of the mode of action of IVIg has been an obstacle to a more rational use and schedule of administration of IVIg and to the improvement of the existing IVIg preparations. Several nonmutually exclusive mechanisms have been proposed to account for the beneficial immunomodulatory effects of IVIg. These include the functional blockade of Fc receptors on phagocytes, inhibition of the deposition of activated complement components on target cells, modulation of the secretion of cytokines and cytokine antagonists, interference with T and B cell proliferation, neutralization of pathological autoantibodies, and long-term selection of immune repertoires.

Intravenous immune globulins. A review of their uses in selected immunodeficiency and autoimmune diseases

Intravenous immune globulin (IGIV) was introduced a decade ago as a therapy for primary immunodeficiency diseases. It proved to be a valuable therapeutic substance for this purpose and is now considered to be the treatment of choice. The intent was to supply ubiquitous anti-infectious agent antibodies through passive immunisation to replace deficient circulating antibody content. During such therapy, unexpected benefits were noted in thrombocytopenic patients. Since that time, the therapeutic indications for IGIV infusions have greatly increased, with a particular interest in infectious, haematological and autoimmune diseases. This review summarises the status of IGIV therapy in haematological diseases within the categories of primary immunodeficiency diseases, secondary immunodeficiency states and autoimmune syndromes. The majority of firm data have been gathered on the treatment of patients with primary immunodeficiency disease. These data are reviewed from the aspect of anticipated therapeutic response and side effects. Emphasis should be placed on the IgG circulating blood levels as there is a need for individualizing therapy because of marked interindividual patient variation. The use of IGIV therapy in primary and secondary immunodeficiency states should consider the potential benefits to be attained in haematological malignancies and related complications which may be magnified by chemotherapy and radiation therapy. The mode of action of IGIV in autoimmune diseases, although not yet precisely determined, may involve establishing reticuloendothelial blockade or immunomodulation by supplying anti-idiotype antibodies.