The Production Processes and Biological Effects of Intravenous Immunoglobulin

In vivo antiviral efficacy of LCTG-002, a pooled, purified human milk secretory IgA product, against SARS-CoV-2 in a murine model of COVID-19

Immunoglobulin A (IgA) is the most abundant antibody (Ab) in human mucosae, with secretory form (sIgA) being dominant and uniquely stable. sIgA is challenging to produce recombinantly but is naturally found in human milk, which could be considered a global resource for this biologic, justifying its development as a mucosal therapeutic. Presently, SARS-CoV-2 was utilized as a model mucosal pathogen, and methods were developed to efficiently extract human milk sIgA from donors who were naïve to SARS-CoV-2 or had recovered from infection that elicited high-titer anti-SARS-CoV-2 Spike sIgA in their milk (pooled to make LCTG-002). Mass spectrometry determined that proteins with a relative abundance of 1% or greater were all associated with sIgA. Western blot demonstrated that all batches consisted predominantly of sIgA. Compared to control IgA, LCTG-002 demonstrated significantly higher Spike binding (mean endpoint of 0.87 versus 5.87). LCTG-002 was capable of blocking the Spike receptor-binding domain - angiotensin-converting enzyme 2 (ACE2) interaction with significantly greater potency compared to control (mean LCTG-002 IC50 154ug/mL versus 50% inhibition not achieved for control), and exhibited significant neutralization activity against Spike-pseudotyped virus infection (mean LCTG-002 IC50 49.8ug/mL versus 114.5ug/mL for control). LCTG-002 was tested for its capacity to reduce viral lung burden in K18+hACE2 transgenic mice inoculated with SARS-CoV-2. LCTG-002 significantly reduced SARS-CoV-2 titers compared to control when administered at 0.25 mg/day or 1 mg/day, with a maximum TCID50 reduction of 4.9 logs. This innovative study demonstrates that LCTG-002 is highly pure and efficacious in vivo, supporting further development of milk-derived, polyclonal sIgA therapeutics.

Proteomic profiling reveals diagnostic signatures and pathogenic insights in multisystem inflammatory syndrome in children

Multisystem inflammatory syndrome in children (MIS-C) is a severe disease that emerged during the COVID-19 pandemic. Although recognized as an immune-mediated condition, the pathogenesis remains unresolved. Furthermore, the absence of a diagnostic test can lead to delayed immunotherapy. Using state-of-the-art mass-spectrometry proteomics, assisted by artificial intelligence (AI), we aimed to identify a diagnostic signature for MIS-C and to gain insights into disease mechanisms. We identified a highly specific 4-protein diagnostic signature in children with MIS-C. Furthermore, we identified seven clusters that differed between MIS-C and controls, indicating an interplay between apolipoproteins, immune response proteins, coagulation factors, platelet function, and the complement cascade. These intricate protein patterns indicated MIS-C as an immunometabolic condition with global hypercoagulability. Our findings emphasize the potential of AI-assisted proteomics as a powerful and unbiased tool for assessing disease pathogenesis and suggesting avenues for future interventions and impact on pediatric disease trajectories through early diagnosis.

Dosing of Convalescent Plasma and Hyperimmune Anti-SARS-CoV-2 Immunoglobulins: A Phase I/II Dose-Finding Study

BACKGROUND AND OBJECTIVE

During the COVID-19 pandemic, trials on convalescent plasma (ConvP) were performed without preceding dose-finding studies. This study aimed to assess potential protective dosing regimens by constructing a population pharmacokinetic (popPK) model describing anti-SARS-CoV-2 antibody titers following the administration of ConvP or hyperimmune globulins (COVIg).

METHODS

Immunocompromised patients, testing negative for anti-SARS-CoV-2 spike antibodies despite vaccination, received a range of anti-SARS-CoV-2 antibodies in the form of COVIg or ConvP infusion. The popPK analysis was performed using NONMEM v7.4. Monte Carlo simulations were performed to assess potential COVIg and ConvP dosing regimens for prevention of COVID-19.

RESULTS

Forty-four patients were enrolled, and data from 42 were used for constructing the popPK model. A two-compartment elimination model with mixed residual error best described the Nab-titers after administration. Inter-individual variation was associated to CL (44.3%), V1 (27.3%), and V2 (29.2%). Lean body weight and type of treatment (ConvP/COVIg) were associated with V1 and V2, respectively. Median elimination half-life was 20 days (interquartile range: 17-25 days). Simulations demonstrated that even monthly infusions of 600 mL of the ConvP or COVIg used in this trial would not achieve potentially protective serum antibody titers for > 90% of the time. However, as a result of hybrid immunity and/or repeated vaccination, plasma donors with extremely high antibody titers are now readily available, and a > 90% target attainment should be possible.

CONCLUSION

The results of this study may inform future intervention studies on the prophylactic and therapeutic use of antiviral antibodies in the form of ConvP or COVIg.

CLINICAL TRIAL REGISTRATION NUMBER

NL9379 (The Netherlands Trial Register).

Immunoglobulin replacement products protect against SARS-CoV-2 infection in vivo despite poor neutralizing activity

Immunoglobulin (IG) replacement products are used routinely in patients with immune deficiency and other immune dysregulation disorders who have poor responses to vaccination and require passive immunity conferred by commercial antibody products. The binding, neutralizing, and protective activity of intravenously administered IG against SARS-CoV-2 emerging variants remains unknown. Here, we tested 198 different IG products manufactured from December 2019 to August 2022. We show that prepandemic IG had no appreciable cross-reactivity or neutralizing activity against SARS-CoV-2. Anti-spike antibody titers and neutralizing activity against SARS-CoV-2 WA1/2020 D614G increased gradually after the pandemic started and reached levels comparable to vaccinated healthy donors 18 months after the diagnosis of the first COVID-19 case in the United States in January 2020. The average time between production to infusion of IG products was 8 months, which resulted in poor neutralization of the variant strain circulating at the time of infusion. Despite limited neutralizing activity, IG prophylaxis with clinically relevant dosing protected susceptible K18-hACE2-transgenic mice against clinical disease, lung infection, and lung inflammation caused by the XBB.1.5 Omicron variant. Moreover, following IG prophylaxis, levels of XBB.1.5 infection in the lung were higher in FcγR-KO mice than in WT mice. Thus, IG replacement products with poor neutralizing activity against evolving SARS-CoV-2 variants likely confer protection to patients with immune deficiency disorders through Fc effector function mechanisms.

Nonspecific Orbital Inflammation (NSOI): Unraveling the Molecular Pathogenesis, Diagnostic Modalities, and Therapeutic Interventions

Nonspecific orbital inflammation (NSOI), colloquially known as orbital pseudotumor, sometimes presents a diagnostic and therapeutic challenge in ophthalmology. This review aims to dissect NSOI through a molecular lens, offering a comprehensive overview of its pathogenesis, clinical presentation, diagnostic methods, and management strategies. The article delves into the underpinnings of NSOI, examining immunological and environmental factors alongside intricate molecular mechanisms involving signaling pathways, cytokines, and mediators. Special emphasis is placed on emerging molecular discoveries and approaches, highlighting the significance of understanding molecular mechanisms in NSOI for the development of novel diagnostic and therapeutic tools. Various diagnostic modalities are scrutinized for their utility and limitations. Therapeutic interventions encompass medical treatments with corticosteroids and immunomodulatory agents, all discussed in light of current molecular understanding. More importantly, this review offers a novel molecular perspective on NSOI, dissecting its pathogenesis and management with an emphasis on the latest molecular discoveries. It introduces an integrated approach combining advanced molecular diagnostics with current clinical assessments and explores emerging targeted therapies. By synthesizing these facets, the review aims to inform clinicians and researchers alike, paving the way for molecularly informed, precision-based strategies for managing NSOI.

Changes in immunoglobulin levels during clozapine treatment in schizophrenia

BACKGROUND AND HYPOTHESIS

Use of clozapine in treatment-resistant schizophrenia is often limited due to risk of adverse effects. Cross-sectional associations between clozapine treatment and low immunoglobulin levels have been reported, however prospective studies are required to establish temporal relationships. We tested the hypothesis that reductions in immunoglobulin levels would occur over the first 6 months following initiation of clozapine treatment. Relationships between immunoglobulin levels and symptom severity over the course of clozapine treatment were also explored.

DESIGN

This prospective observational study measured immunoglobulin (Ig) levels (A, M and G) in 56 patients with treatment-resistant schizophrenia at 6-, 12- and 24-weeks following initiation with clozapine. Clinical symptoms were also measured at 12 weeks using the positive and negative syndrome scale (PANSS).

RESULTS

IgA, IgG and IgM all decreased during clozapine treatment. For IgA and IgG the reduction was significant at 24 weeks (IgA: β = -32.66, 95% CI = -62.38, -2.93, p = 0.03; IgG: β = -63.96, 95% CI = -118.00, -9.31, p = 0.02). For IgM the reduction was significant at 12 and 24 weeks (12 weeks: β = -23.48, 95% CI = -39.56, -7.42, p = 0.004; 24 weeks: β = -33.12, 95 %CI = -50.30, -15.94, p = <0.001). Reductions in IgA and IgG during clozapine treatment were correlated with reductions in PANSS-total over 12 weeks (n = 32, IgA r = 0.59, p = 0.005; IgG r = 0.48, p = 0.03).

CONCLUSIONS

The observed reductions in immunoglobulin levels over six months of clozapine treatment add further evidence linking clozapine to secondary antibody deficiency. Associations between Ig reduction and symptom improvement may however indicate that immune mechanisms contribute to both desirable and undesirable effects of clozapine.

Unveiling the autoreactome: Proteome-wide immunological fingerprints reveal the promise of plasma cell depleting therapy

The prevalence and burden of autoimmune and autoantibody mediated disease is increasing worldwide, yet most disease etiologies remain unclear. Despite numerous new targeted immunomodulatory therapies, comprehensive approaches to apply and evaluate the effects of these treatments longitudinally are lacking. Here, we leverage advances in programmable-phage immunoprecipitation (PhIP-Seq) methodology to explore the modulation, or lack thereof, of proteome-wide autoantibody profiles in both health and disease. We demonstrate that each individual, regardless of disease state, possesses a distinct set of autoreactivities constituting a unique immunological fingerprint, or "autoreactome", that is remarkably stable over years. In addition to uncovering important new biology, the autoreactome can be used to better evaluate the relative effectiveness of various therapies in altering autoantibody repertoires. We find that therapies targeting B-Cell Maturation Antigen (BCMA) profoundly alter an individual's autoreactome, while anti-CD19 and CD-20 therapies have minimal effects, strongly suggesting a rationale for BCMA or other plasma cell targeted therapies in autoantibody mediated diseases.

Intravenous Immunoglobulin-Associated Severe Hemolytic Anemia

Intravenous immunoglobulin (IVIG) is used to treat immunodeficiency conditions, neuro-immunological, infection-related, autoimmune, and inflammatory disorders and is typically well tolerated. A hematological adverse reaction such as hemolytic anemia and neutropenia is known to occur with IVIG, which is usually transient and subclinical. However, severe hemolytic anemia is known to occur in some cases. We present a case of a 66-year-old man who developed severe symptomatic hemolytic anemia after receiving IVIG for acute inflammatory demyelinating polyneuropathy (AIDP). The patient had known risk factors such as non-O blood group, high cumulative dose of IVIG, and underlying autoimmune condition, which would have put him at high risk for developing hemolytic anemia after IVIG. Therefore, it is prudent for clinicians to have increased awareness regarding the potential for severe hemolysis and closely monitor these patients with risk factors after treatments to identify this adverse reaction before more severe complications occur.

Practise of Immunoglobulin Replacement Therapy in Primary and Secondary Immunodeficiencies: A Single Centre Experience from Malaysia

Background

Intravenous immunoglobulin (IVIG) replacement therapy is increasingly in demand. This study focused on the characteristics of IVIG usage and associated factors toward the frequency status of IVIG among patients in Hospital Kuala Lumpur.

Methods

A retrospective cross-sectional study was performed on patients who received IVIG in Hospital Kuala Lumpur. Data were extracted from the request forms for IVIG recorded in the Pharmacy Department from January 2018 until December 2019. Chi-squared test and t-test analysis were used for statistical analysis, and a P-value of < 0.05 was considered significant.

Results

A total of 482 patients received IVIG in Hospital Kuala Lumpur. There were 243 (50.4%) females and 228 (47.3%) males with median age of the patients was 27 years old. The highest indications for IVIG among all patients were hypogammaglobulinemia and other deficiency states in 127 patients (26.3%). The most common indication for one-off treatment in adults was hypogammaglobulinemia and other deficiency states, 35%; whereas in paediatrics, it was Kawasaki disease, 20.3%. The highest indication for regular therapy among adult patients was chronic inflammatory demyelinating polyneuropathy (23.4%), while in paediatrics it was sepsis (31.1%). The clinical category was associated with the frequency status of IVIG usage in both adult and paediatric cohorts with P = 0.004 and P = 0.017, respectively.

Conclusion

There were significant differences between the indication of one-off treatment and regular therapy among adult and paediatric patients. A national guideline on the prescription of IVIG for patients is instantly needed to help clinicians in prescribing IVIG appropriately.

Inpatient Rheumatology Consultation Prompted by Positive Autoantibodies in Patients Receiving Intravenous Immunoglobulin Therapy: A Case Series and Literature Review

Intravenous immunoglobulin (IVIG) is a therapeutic preparation used in the treatment of multiple diseases. Autoimmune testing with antinuclear antibody (ANA) screening is often obtained for some of these conditions, but only after initiation of IVIG treatment. This can present a diagnostic dilemma in hospitalized patients and may trigger a rheumatology consultation. We describe our consultative inpatient two-year experience with five such patients and review the pertinent literature. A retrospective chart review of rheumatology inpatient consultations between 6-2018 and 6-2020 at our academic tertiary care hospital for post-IVIG positive serologies was performed. A pertinent literature review was performed. Five patients had a positive ANA and other autoantibodies detected in their serum after they received IVIG for non-rheumatological conditions. None of these patients met the criteria for a connective tissue disease. The literature review identified a total of 58 patients from case reports and case series, several of whom tested positive for ANA and other antibodies after receiving IVIG. Studies assessing specific IVIG products detected multiple autoantibodies in the donor pool. Autoimmune testing is initiated on inpatients receiving IVIG for non-rheumatological conditions. If an autoantibody ANA screen is positive, a rheumatology consultation may be requested. In the absence of pre-IVIG antibody tests it is difficult to interpret post-IVIG-positive antibodies. Whether such positive antibodies are of clinicopathological significance is determined by clinical judgment and time.

Peptide-crosslinked molecularly imprinted polymers for efficient separation of immunoglobulin G from human serum

Low-cost and highly effective methods are highly desirable to replace the costly ethanol fractionation and affinity chromatography in IgG isolation from human plasma. Molecularly imprinted polymers (MIPs) of IgG are potential candidates, however, they still suffer from severe problems such as difficult template removal and low imprinting efficiency. Here, a recently developed strategy was adopted to overcome these problems. The MIPs were synthesized using poly(L-glutamic acid) (PLGA) peptide crosslinkers instead of commonly used crosslinkers, such as N,N-methylenebisacrylamide (BIS). Because of the pH-induced helix-coil transition and the precise folding of the peptide segments in the polymers, the imprint cavities can be enlarged by adjusting the pH from 5.0 to 7.0, but their original size and shape are restored when the pH is adjusted back. Therefore, the IgG template can be eluted completely under mild conditions, and significantly improved imprinting efficiency can be achieved. Compared with BIS-crosslinked MIP, 8.6 times more binding sites can be created by molecular imprinting PLGA-crosslinked MIP. The factors influencing the performance of the MIP were studied systematically. An optimized MIP with a high adsorption capacity (612.5 mg g^-1), high IF (4.92), and high selectivity was obtained. The adsorption capacity and selectivity of the MIP are much higher than the previously reported IgG MIPs. Because of its high adsorption capacity and selectivity, it can separate IgG from human serum effectively, affording high purity products.

Polyvalent human immunoglobulin for infectious diseases: Potential to circumvent antimicrobial resistance

Antimicrobial resistance (AMR) is a global health problem that causes more than 1.27 million deaths annually; therefore, it is urgent to focus efforts on solving or reducing this problem. The major causes of AMR are the misuse of antibiotics and antimicrobials in agriculture, veterinary medicine, and human medicine, which favors the selection of drug-resistant microbes. One of the strategies proposed to overcome the problem of AMR is to use polyvalent human immunoglobulin or IVIG. The main advantage of this classic form of passive immunization is its capacity to enhance natural immunity mechanisms to eliminate bacteria, viruses, or fungi safely and physiologically. Experimental data suggest that, for some infections, local administration of IVIG may produce better results with a lower dose than intravenous application. This review presents evidence supporting the use of polyvalent human immunoglobulin in AMR, and the potential and challenges associated with its proposed usage.

High Thyroglobulin Antibody Following Intravenous Immunoglobulin Therapy in Athyreotic Differentiated Thyroid Cancer Patients

American Thyroid Association guidelines recommend to follow athyreotic differentiated thyroid cancer patients with measurement of serum thyroglobulin and thyroglobulin antibody as tumor markers. The guidelines recommend that rising thyroglobulin or thyroglobulin antibody should prompt additional investigations and potentially additional therapies. Two patients with differentiated thyroid cancer who also received intravenous immunoglobulin are presented. Their cancer history, serial thyroglobulin and thyroglobulin antibody measurements and imaging findings relative to the time course of intravenous immunoglobulin treatment are illustrated. Acute rise in thyroglobulin antibody led to further imaging which did not show cancer progression. Additional history documented an intravenous immunoglobulin treatment exposure had occurred within the past one to two months before the increased thyroglobulin antibody measurement. Follow-up serial thyroglobulin antibody levels declined over time after the intravenous immunoglobulin exposure. Intravenous immunoglobulin, which is a pooled human serum product, contains thyroglobulin antibody. Commercially available thyroglobulin antibody assays may detect the thyroglobulin antibody contained within the administered intravenous immunoglobulin, leading to alarm and further imaging to exclude progressive malignancy. Thyroglobulin antibody rise and fall can be demonstrated in relationship to intravenous immunoglobulin time of administration. Thyroglobulin antibody is higher at time-points sooner than at later time-points following intravenous immunoglobulin treatments. Intravenous immunoglobulin may be a benign source of transiently high thyroglobulin antibody measured in the follow-up of differentiated thyroid cancer patients. Repeat thyroglobulin and thyroglobulin antibody testing one to two months following a higher level in a patient treated with intravenous immunoglobulin may avoid unnecessary imaging to look for progressive malignancy.

Validation of Viral Inactivation Protocols for Therapeutic Blood Products against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2)

Therapeutic blood products including convalescent plasma/serum and immunoglobulins concentrated from convalescent plasma, such as intravenous immunoglobulins or hyperimmune globulins, and monoclonal antibodies are passive immunotherapy options for novel coronavirus disease 2019 (COVID-19). They have been shown to improve the clinical status and biological and radiological parameters in some groups of COVID-19 patients. However, blood products are still potential sources of virus transmission in recipients. The use of pathogen reduction technology (PRT) should increase the safety of the products. The purpose of this study was to determine the impact of solvent/detergents (S/D) procedures on SARS-COV-2 infectivity elimination in the plasma of donors but also on COVID-19 convalescent serum (CCS) capacity to neutralize SARS-COV-2 infectivity. In this investigation, S/D treatment for all experiments was performed at a shortened process time (30 min). We first evaluated the impact of S/D treatments (1% TnBP/1% TritonX-45 and 1% TnBP/1% TritonX-100) on the inactivation of SARS-COV-2 pseudoparticles (SARS-COV-2pp)-spiked human plasma followed by S/D agent removal using a Sep-Pak Plus C18 cartridge. Both treatments were able to completely inactivate SARS-COV-2pp infectivity to an undetectable level. Moreover, the neutralizing activity of CCS against SARS-COV-2pp was preserved after S/D treatments. Our data suggested that viral inactivation methods using such S/D treatments could be useful in the implementation of viral inactivation/elimination processes of therapeutic blood products against SARS-COV-2.

Systems biology and artificial intelligence analysis highlights the pleiotropic effect of IVIg therapy in autoimmune diseases with a predominant role on B cells and complement system

Intravenous immunoglobulin (IVIg) is used as treatment for several autoimmune and inflammatory conditions, but its specific mechanisms are not fully understood. Herein, we aimed to evaluate, using systems biology and artificial intelligence techniques, the differences in the pathophysiological pathways of autoimmune and inflammatory conditions that show diverse responses to IVIg treatment. We also intended to determine the targets of IVIg involved in the best treatment response of the evaluated diseases. Our selection and classification of diseases was based on a previously published systematic review, and we performed the disease characterization through manual curation of the literature. Furthermore, we undertook the mechanistic evaluation with artificial neural networks and pathway enrichment analyses. A set of 26 diseases was selected, classified, and compared. Our results indicated that diseases clearly benefiting from IVIg treatment were mainly characterized by deregulated processes in B cells and the complement system. Indeed, our results show that proteins related to B-cell and complement system pathways, which are targeted by IVIg, are involved in the clinical response. In addition, targets related to other immune processes may also play an important role in the IVIg response, supporting its wide range of actions through several mechanisms. Although B-cell responses and complement system have a key role in diseases benefiting from IVIg, protein targets involved in such processes are not necessarily the same in those diseases. Therefore, IVIg appeared to have a pleiotropic effect that may involve the collaborative participation of several proteins. This broad spectrum of targets and 'non-specificity' of IVIg could be key to its efficacy in very different diseases.

Intravenous Methylprednisolone Pulse Therapy Versus Intravenous Immunoglobulin in the Prevention of Coronary Artery Disease in Children with Kawasaki Disease: A Randomized Controlled Trial

Background: Kawasaki disease (KD) is often complicated by coronary artery lesion (CAL), including dilatation or aneurysms. Intravenous immunoglobulin (IVIG) is used with aspirin to prevent CAL in KD.

Objective: Given that the primary treatment for other vasculitis is the use of corticosteroids, this study has been performed to evaluate the effect of intravenous methylprednisolone pulse (IVMP) therapy in preventing CAL in KD.

Method: A randomized, single-blind clinical trial was conducted on 40 KD patients aged six months to five years. Patients were randomized into two groups according to the main treatment plan in addition to aspirin: case group (IVMP for three consecutive days and then oral prednisolone for three days) and control group (intravenous immunoglobulin 2 g/kg). Echocardiography was performed for all children at least three times, during the acute phase, two weeks, and two months later.

Results: Data analysis at the end of the study was done on 40 patients (20 patients in each group). There were no significant differences in age and sex distribution, mean fever, and acute phase duration, as well as baseline echocardiography in the two groups. The frequency of CAL was 20% in the case group and 45% in the control group, after two weeks (p<0.05), but there was no significant difference between two groups in types of coronary artery lesion after two weeks and the frequency and severity of CAL after two months.

Conclusion: IVMP as initial line therapy effectively control systemic and vascular inflammation and decrease coronary artery damage in KD.

mRNA vaccine boosting enhances antibody responses against SARS-CoV-2 Omicron variant in individuals with antibody deficiency syndromes

Individuals with primary antibody deficiency (PAD) syndromes have poor humoral immune responses requiring immunoglobulin replacement therapy. We followed individuals with PAD after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination by evaluating their immunoglobulin replacement products and serum for anti-spike binding, Fcγ receptor (FcγR) binding, and neutralizing activities. The immunoglobulin replacement products tested have low anti-spike and receptor-binding domain (RBD) titers and neutralizing activity. In coronavirus disease 2019 (COVID-19)-naive individuals with PAD, anti-spike and RBD titers increase after mRNA vaccination but wane by 90 days. Those vaccinated after SARS-CoV-2 infection develop higher and more sustained responses comparable with healthy donors. Most vaccinated individuals with PAD have serum-neutralizing antibody titers above an estimated correlate of protection against ancestral SARS-CoV-2 and Delta virus but not against Omicron virus, although this is improved by boosting. Thus, some immunoglobulin replacement products likely have limited protective activity, and immunization and boosting of individuals with PAD with mRNA vaccines should confer at least short-term immunity against SARS-CoV-2 variants, including Omicron.

Immune globulin therapy and kidney disease: Overview and screening, monitoring, and management recommendations

Purpose

This report calls attention to the potential risks of diminished kidney function when administering immune globulin (IG). The goal is to increase awareness of chronic kidney disease (CKD) and kidney function impairment in patients receiving IG and provide recommendations for screening, monitoring, and management to promote risk prevention and mitigation.

Summary

Human IG preparations for intravenous (IVIG) or subcutaneous (SCIG) administration are the mainstay of treatment in patients with primary immunodeficiency diseases. Increasingly, IVIG at high doses (1,000 to 2,400 mg/kg) is also used as a treatment for a variety of autoimmune and inflammatory conditions. Although some autoinflammatory disorders respond to a single course of IVIG therapy, the majority of patients require long-term, regular infusions, thereby increasing the overall risks. Often, both patients and physicians treating adults with IG are unaware of underlying CKD or kidney function impairment. This lack of awareness constitutes a major risk factor for potential worsening, particularly when using high doses of IVIG. Therefore, screening of all patients for CKD and kidney function impairment before the use of IG is essential. Identification of the cause of kidney impairment is strongly encouraged, as IG therapy may need to be modified.

Conclusion

As detailed here, there are potential risks to patients with impaired kidney function with administration of IG, particularly at high doses. Product selection, volume, route of administration, and rate of infusion may impact those with compromised kidney function. Therefore, screening of all patients for CKD and kidney function impairment before the use of IVIG and SCIG, as well as ongoing monitoring and management, is critical. As with all potential adverse drug reactions, the best approach is to prevent them.

Strategies for Glycoengineering Therapeutic Proteins

Almost all therapeutic proteins are glycosylated, with the carbohydrate component playing a long-established, substantial role in the safety and pharmacokinetic properties of this dominant category of drugs. In the past few years and moving forward, glycosylation is increasingly being implicated in the pharmacodynamics and therapeutic efficacy of therapeutic proteins. This article provides illustrative examples of drugs that have already been improved through glycoengineering including cytokines exemplified by erythropoietin (EPO), enzymes (ectonucleotide pyrophosphatase 1, ENPP1), and IgG antibodies (e.g., afucosylated Gazyva^®, Poteligeo^®, Fasenra™, and Uplizna^®). In the future, the deliberate modification of therapeutic protein glycosylation will become more prevalent as glycoengineering strategies, including sophisticated computer-aided tools for “building in” glycans sites, acceptance of a broad range of production systems with various glycosylation capabilities, and supplementation methods for introducing non-natural metabolites into glycosylation pathways further develop and become more accessible.

Intravenous immunoglobulin treatment stabilizing a patient with Anti-PL7 antisynthetase syndrome with interstitial lung disease and eosinophilic inflammation

Antisynthetase syndrome (AS) is a rare autoimmune disease characterized by autoantibodies against aminoacyl-transfer RNA synthetase and clinical features which can include interstitial lung disease (ILD). Current available evidence of treatment is based on expert opinions and case reports. Here, we present a patient with an initial diagnosis of eosinophilic pneumonia, who was later diagnosed with anti-PL7 antisynthetase syndrome with ILD and eosinophilic inflammation. The patient was non-responsive to classic immunosuppressants but responded remarkably well to intravenous immunoglobulin.

Fc receptors gone wrong: A comprehensive review of their roles in autoimmune and inflammatory diseases

Systemic autoimmune and inflammatory diseases have a complex and only partially known pathophysiology with various abnormalities involving all the components of the immune system. Among these components, antibodies, and especially autoantibodies are key elements contributing to autoimmunity. The interaction of antibody fragment crystallisable (Fc) and several distinct receptors, namely Fc receptors (FcRs), have gained much attention during the recent years, with possible major therapeutic perspectives for the future. The aim of this review is to comprehensively describe the known roles for FcRs (activating and inhibitory FcγRs, neonatal FcR [FcRn], FcαRI, FcεRs, Ro52/tripartite motif containing 21 [Ro52/TRIM21], FcδR, and the novel Fc receptor-like [FcRL] family) in systemic autoimmune and inflammatory disorders, namely rheumatoid arthritis, Sjögren's syndrome, systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathies, mixed connective tissue disease, Crohn's disease, ulcerative colitis, immunoglobulin (Ig) A vasculitis, Behçet's disease, Kawasaki disease, IgG4-related disease, immune thrombocytopenia, autoimmune hemolytic anemia, antiphospholipid syndrome and heparin-induced thrombocytopenia.

Combinatorial therapy with immunosuppressive, immunomodulatory and tear substitute eyedrops ("Triple Play") in Recalcitrant Immunological Ocular Surface Diseases

PURPOSE

The current paradigm for therapy of recalcitrant ocular surface diseases (OSD) consists of a sequential, step-up treatment approach. A combinatorial topical therapy (anti-inflammatory/immunosuppressive [steroid] with immunomodulatory [pooled human immune globulin] and tear substitute [serum]) that simultaneously targets several immunological pathways may be more efficacious. This report evaluates if the combinatorial therapy resulted in clinical benefit in patients with recalcitrant OSD.

METHODS

We performed a retrospective case study of patients receiving topical, preservative-free, compounded formulations of steroids, pooled human immune globulin, and serum tears. Outcome measures included visual acuity, ocular surface disease index (OSDI), ocular discomfort score, subjective global assessment (SGA), corneal staining, conjunctival redness, and slit lamp photographs.

RESULTS

Patients consisted of one male and 11 females ranging in age from 27 to 87 years old. Pathologies included ocular graft-versus-host disease (n = 4), Sjögren's syndrome (n = 3), ocular cicatricial pemphigoid (n = 1), pemphigus vulgaris (n = 1), peripheral ulcerative keratitis (n = 1), Stevens-Johnson syndrome (n = 1), and giant papillary conjunctivitis (n = 1). All patients were "improved" or "much improved" on SGA after combinatorial therapy. There was a clinically meaningful reduction in OSDI, ocular discomfort, corneal staining, and conjunctival injection. Additionally, three patients had improvement in their visual acuity (one from 20/400 to 20/20). Adverse effects included increased intraocular pressure in two patients, presumably due to topical steroid use.

CONCLUSIONS

Combinatorial therapy provides clinical benefit by reducing the symptoms and signs in recalcitrant OSD. Our study provides the rationale for performing prospective clinical trials to evaluate the efficacy of combinatorial therapy for treating recalcitrant OSD.

Plasma cell biology: Foundations for targeted therapeutic development in transplantation

Solid organ transplantation is a life-saving procedure for patients with end-stage organ disease. Over the past 70 years, tremendous progress has been made in solid organ transplantation, particularly in T-cell-targeted immunosuppression and organ allocation systems. However, humoral alloimmune responses remain a major challenge to progress. Patients with preexisting antibodies to human leukocyte antigen (HLA) are at significant disadvantages in regard to receiving a well-matched organ, moreover, those who develop anti-HLA antibodies after transplantation face a significant foreshortening of renal allograft survival. Historical therapies to desensitize patients prior to transplantation or to treat posttransplant AMR have had limited effectiveness, likely because they do not significantly reduce antibody levels, as plasma cells, the source of antibody production, remain largely unaffected. Herein, we will discuss the significance of plasma cells in transplantation, aspects of their biology as potential therapeutic targets, clinical challenges in developing strategies to target plasma cells in transplantation, and lastly, novel approaches that have potential to advance the field.

An overview on the investigation of nanomaterials' effect on plasma components: immunoglobulins and coagulation factor VIII, 2010-2020 review

FVIII and immunoglobulins (Igs) are the most prominent plasma proteins, which play a vital role in plasma hemostasis. These proteins have been implemented frequently in protein therapy. Therefore, their maintenance, durability, and stability are highly essential. Herein, various approaches to improve protein functions have been investigated, such as using recombinant protein replacement. In comparison, advances in nanotechnology have provided adequate context to boost biomaterial utilization. In this regard, the applications of various nanoparticles such as polymeric nanomaterials (PEG and PLGA), metal nanoparticles, dendrimers, and lipid based nanomaterials (liposomes and lipid nanoparticles) in stability and the functional improvement of antibodies and coagulation factor VIII (FVIII) have been reviewed from 2010 to 2020. Reviewing related articles has shown that not only can nanomaterials adequately protect the structure of proteins, but have also improved proteins' functions in some cases. For example, the high rate of FVIII instability has been successfully enhanced by bio-PEGylation. Also, utilizing PEGylated liposomes, using the PEG-lip technique for coating nanostructures, leads to FIIIV half-life prolongation. Hence, PEGylation had most impact on the stability of FVIII. Likewise, PEG-coated liposome nano-carriers also presented such a good effect on stability improvements for FVIII due to their ability to tune the immune system by reducing FVIII immunogenicity. Similarly, Ig PEGylation and conjugation to magnetic nanoparticles resulted in increased half-life and better purification of Igs, respectively, without any loss in structural or functional features. Consequently, metal-organic frameworks and recent hybrid systems have been introduced as promising nanomaterials in biomedical applications. As far as we know, this is the first study in this field, which considers the applications of nanoparticles for improving the storage and stability of antibodies and coagulation FVIII.

Production of hyperimmune anti-SARS-CoV-2 intravenous immunoglobulin from pooled COVID-19 convalescent plasma

Background: This study assesses the feasibility of producing hyperimmune anti-COVID-19 intravenously administrable immunoglobulin (C-IVIG) from pooled convalescent plasma (PCP) to provide a safe and effective passive immunization treatment option for COVID-19. Materials & methods: PCP was fractionated by modified caprylic acid precipitation followed by ultrafiltration/diafiltration to produce hyperimmune C-IVIG. Results: In C-IVIG, the mean SARS-CoV-2 antibody level was found to be threefold (104 ± 30 cut-off index) that of the PCP (36 ± 8.5 cut-off index) and mean protein concentration was found to be 46 ± 3.7 g/l, comprised of 89.5% immunoglobulins. Conclusion: The current method of producing C-IVIG is feasible as it uses locally available PCP and simpler technology and yields a high titer of SARS-CoV-2 antibody. The safety and efficacy of C-IVIG will be evaluated in a registered clinical trial (NCT04521309).

Practical Aspects of Transitioning from Intravenous to Subcutaneous Immunoglobulin Therapy in Neuromuscular Disorders

Recent evidence shows that subcutaneous immunoglobulin (SCIG) is as efficacious as intravenous immunoglobulin (IVIG) and has a better safety profile and acceptance rate among patients with neuromuscular disorders who require maintenance IVIG treatment. Awareness of the practical aspects of patient selection, enrollment, dose calculation, administration, and follow-up would help physicians coordinate a smooth and seamless transition from IVIG to SCIG. SCIG is ideally offered to patients having intolerable side effects during IVIG or wearing-off effect and in those keen for treatment autonomy. The weekly dose of SCIG is calculated by multiplying the maintenance dose of IVIG by the dose adjustment factor and dividing by the interval between IVIG in weeks and is initiated 1 week after the last dose of IVIG. The physician places the order for the SCIG and the clinic nurse or the physician refers the patient to the home care nursing program for further education and training. The necessary supplies are dispatched to the patient who would also collect the SCIG from the transfusion center of the nearest hospital. The patient is educated on assembling and administering the infusion, and home visits are continued until the patient or caregiver is confident. Regular follow-up with the patient is maintained to assess treatment response and side effects if any. With a smooth transition, most patients have excellent tolerance to SCIG and in our experience seldom request switching back to IVIG. Transitioning patients from IVIG to SCIG offers several advantages and thus, in general, is preferable for multiple stakeholders.

Neonatal Fc receptor in human immunity: Function and role in therapeutic intervention

The humoral immune response provides specific, long-lived protection against invading pathogens, via immunoglobulin production and other memory functions. IgG, the most abundant immunoglobulin isotype, has the longest half-life and protects against bacterial and viral infections. The neonatal Fc receptor (FcRn) transports IgG across barriers, for example, the placenta, enhancing fetal humoral immunity to levels similar to their mothers'. Importantly, FcRn, by protecting IgG from intracellular degradation, results in an approximately 21-day circulating IgG half-life and high plasma levels; similarly, FcRn recycles albumin and is the portal of entry for enteric cytopathic human orphan (echo) virus infection. Dysregulated immune responses may lead to antibodies against self-antigens (autoantibodies), resulting in organ-specific or systemic autoimmune diseases. Autoantibody-mediated diseases have been treated by nonspecific immunoglobulin-lowering/modulating therapies, including immunoadsorption, plasma exchange, and high-dose intravenous immunoglobulin. However, targeting FcRn with specific inhibitors results in reduction in only IgG levels. The effectiveness of FcRn inhibitors in autoimmune diseases, including myasthenia gravis and immune thrombocytopenia, provides further evidence that IgG is a primary driver in these autoantibody-mediated diseases. We describe the role of FcRn in human biology, including insights that clinical testing of FcRn inhibitors have provided into FcRn biology and autoimmune disease mechanisms, allowing fact-based speculation on their therapeutic potential.

Importance of immunoglobulin therapy for COVID-19 patients with lymphocytopenia

BACKGROUND

The global coronavirus disease 2019 (COVID-19) was announced as pandemic by the World Health Organization (WHO). With the increased number of infected and dead victims daily all over the world, it becomes necessary to stop or overcome its rapid spread.Main bodyAlthough the production of vaccine or even specified effective anti-virus may take about six months to a year, intravenous immunoglobulin (IVIg) may be clinically used as a safe treatment to save and improve the quality of life of patients with a variety of immunodeficiency diseases such as lymphocytopenia, which is a common clinical feature in COVID-19.

CONCLUSION

Through the current review, it was concluded that this passive immunization may promote the immunity to better fight against the virus, so the survival of the patients could be kept longer. The efficacy of immunotherapy with IVIg would be greater if the immune IgG antibodies were collected from convalescent plasma therapy.

Intravenous Immune Globulin Uses in the Fetus and Neonate: A Review

Intravenous immune globulin (IVIG) is made after processing plasma from healthy donors. It is composed mainly of pooled immunoglobulin and has clinical evidence-based applications in adult and pediatric populations. Recently, several clinical applications have been proposed for managing conditions in the neonatal population, such as hemolytic disease of the newborn, treatment, and prophylaxis for sepsis in high-risk neonates, enterovirus parvovirus and COVID-19 related neonatal infections, fetal and neonatal immune-induced thrombocytopenia, neonatal hemochromatosis, neonatal Kawasaki disease, and some types of immunodeficiency. The dosing, mechanism of action, effectiveness, side effects, and adverse reactions of IVIG have been relatively well studied in adults but are not well described in the neonatal population. This review aims to provide the most recent evidence and consensus guidelines about the use of IVIG in the fetus and neonate.

False-positive SARS-CoV-2 serology in 3 children with Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute febrile and eruptive disease with systemic vasculitis predominantly affecting young East Asian children. Recent reports showed that children with KD-like disease from KD low prevalence regions had positive SARS-CoV-2 serology despite a negative SARS-CoV-2 polymerase chain reaction (PCR) in respiratory samples.

OBJECTIVES

To describe 3 pediatric Kawasaki Disease patients with false positive SARS-CoV-2 serology.

STUDY DESIGN

We retrospectively recruited children with KD diagnosed during the COVID-19 outbreak in Hong Kong. Clinical characteristics and laboratory test results including SARS-CoV-2 PCR results were retrieved. We performed a microparticle-based immunoassay for the detection of IgG against nucleoprotein (NP) and spike protein receptor binding domain (RBD), and a microneutralization assay for the detection of neutralizing antibodies.

RESULTS

Three Chinese children with typical KD were identified. They had no epidemiological links with COVID-19 patients and tested negative for SARS-CoV-2 NPA PCR. They were treated with IVIG and aspirin, and were discharged without complications. Subsequently 2 of them were tested positive against anti-RBD and anti-NP antibodies and 1 was tested positive against anti- RBD antibodies. However, microneutralization assay showed that neutralizing antibodies were absent, suggesting a false-positive IgG result.

CONCLUSION

Detection of neutralizing antibodies is recommended to confirm previous SARS-CoV-2 infection in IgG-positive but PCR-negative patients.

The utility of a monocyte monolayer assay in the assessment of intravenous immunoglobulin-associated hemolysis

BACKGROUND

Hemolysis following the administration of intravenous immunoglobulin (IVIG) is an important adverse event (AE). While the monocyte monolayer assay (MMA) has been used to predict in vivo hemolysis when serologically incompatible blood may be transfused, it has also been shown to correlate with IVIG-associated hemolysis. In this study, the MMA was examined for its utility in assessing the risk of hemolysis after IVIG.

STUDY DESIGN AND METHODS

Forty-two non-blood group O patients receiving high-dose IVIG (≥2 g/kg) were examined using an autologous and allogeneic MMA. Hemolysis was defined by a drop in hemoglobin of ≥1 g/L, a positive direct antiglobulin test (DAT) and eluate, and a decrease in haptoglobin or increase in lactate dehydrogenase and/or reticulocytes.

RESULTS

Forty-two patients provided 50 assessable postinfusion samples, with hemolysis observed in 20 (40%) of cases. Autologous MMA using post-IVIG red blood cells significantly correlated with clinical outcomes when compared to allogeneic MMA (P = .0320 vs .5806, t test). No significant difference in receiver operating characteristics was observed when comparing autologous MMA testing against DAT for the diagnosis of IVIG-associated hemolysis. However, when using samples collected 5 to 10 days after receipt of high-dose IVIG, the autologous MMA had higher sensitivity than the DAT.

CONCLUSION

MMA testing with autologous monocytes collected 5 to 10 days after receipt of high-dose IVIG can be used for the diagnosis of IVIG-associated hemolysis and may be of particular value in cases in which the Day 5 to 10 DAT is negative.

Targeting FcRn for immunomodulation: Benefits, risks, and practical considerations

The neonatal fragment crystallizable (Fc) receptor (FcRn) functions as a recycling mechanism to prevent degradation and extend the half-life of IgG and albumin in the circulation. Several FcRn inhibitors selectively targeting IgG recycling are now moving rapidly toward clinical practice in neurology and hematology. These molecules accelerate the destruction of IgG, reducing pathogenic IgG and IgG immune complexes, with no anticipated effects on IgA, IgM, IgE, complement, plasma cells, B cells, or other cells of the innate or adaptive immune systems. FcRn inhibitors have potential for future use in a much wider variety of antibody-mediated autoimmune diseases. Given the imminent clinical use, potential for broader utility, and novel mechanism of action of FcRn inhibitors, here we review data from 4 main sources: (a) currently available activity, safety, and mechanism-of-action data from clinical trials of FcRn inhibitors; (b) other procedures and treatments that also remove IgG (plasma donation, plasma exchange, immunoadsorption); (c) diseases resulting in loss of IgG; and (d) primary immunodeficiencies with potential mechanistic similarities to those induced by FcRn inhibitors. These data have been evaluated to provide practical considerations for the assessment, monitoring, and reduction of any potential infection risk associated with FcRn inhibition, in addition to highlighting areas for future research.

Intravenous Immunoglobulin G Suppresses Heat Shock Protein (HSP)-70 Expression and Enhances the Activity of HSP90 and Proteasome Inhibitors

Intravenous immunoglobulin G (IVIgG) is approved for primary immunodeficiency syndromes but may induce anti-cancer effects, and while this has been attributed to its anti-inflammatory properties, IgG against specific tumor targets may play a role. We evaluated IVIgG alone, and with a Heat shock protein (HSP)-90 or proteasome inhibitor, using multiple myeloma and mantle cell lymphoma (MCL) cells in vitro, and with the proteasome inhibitor bortezomib in vivo. IVIgG inhibited the growth of all cell lines tested, induced G₁ cell cycle arrest, and suppressed pro-tumor cytokines including Interleukin (IL)-6, IL-8, and IL-10. Genomic and proteomic studies showed that IVIgG reduced tumor cell HSP70-1 levels by suppressing the ability of extracellular HSP70-1 to stimulate endogenous HSP70-1 promoter activity, and reduced extracellular vesicle uptake. Preparations of IVIgG were found to contain high titers of anti-HSP70-1 IgG, and recombinant HSP70-1 reduced the efficacy of IVIgG to suppress HSP70-1 levels. Combining IVIgG with the HSP90 inhibitor AUY922 produced superior cell growth inhibition and correlated with HSP70-1 suppression. Also, IVIgG with bortezomib or carfilzomib was superior to each single agent, and enhanced bortezomib's activity in bortezomib-resistant myeloma cells. Moreover, IVIgG reduced transfer of extracellular vesicles (EVs) to cells, and blocked transfer of bortezomib resistance through EVs. Finally, IVIgG with bortezomib were superior to the single agents in an in vivo myeloma model. These studies support the possibility that anti-HSP70-1 IgG contained in IVIgG can inhibit myeloma and MCL growth by interfering with a novel mechanism involving uptake of exogenous HSP70-1 which then induces its own promoter.

Immunoglobulins with Non-Canonical Functions in Inflammatory and Autoimmune Disease States

Immunoglobulins are known to combine various effector mechanisms of the adaptive and the innate immune system. Classical immunoglobulin functions are associated with antigen recognition and the initiation of innate immune responses. However, in addition to classical functions, antibodies exhibit a variety of non-canonical functions related to the destruction of various pathogens due to catalytic activity and cofactor effects, the action of antibodies as agonists/antagonists of various receptors, the control of bacterial diversity of the intestine, etc. Canonical and non-canonical functions reflect the extreme human antibody repertoire and the variety of antibody types generated in the organism: antigen-specific, natural, polyreactive, broadly neutralizing, homophilic, bispecific and catalytic. The therapeutic effects of intravenous immunoglobulins (IVIg) are associated with both the canonical and non-canonical functions of antibodies. In this review, catalytic antibodies will be considered in more detail, since their formation is associated with inflammatory and autoimmune diseases. We will systematically summarize the diversity of catalytic antibodies in normal and pathological conditions. Translational perspectives of knowledge about natural antibodies for IVIg therapy will be also discussed.

Antibodies Inhibiting the Type III Secretion System of Gram-Negative Pathogenic Bacteria

Pathogenic bacteria are a global health threat, with over 2 million infections caused by Gram-negative bacteria every year in the United States. This problem is exacerbated by the increase in resistance to common antibiotics that are routinely used to treat these infections, creating an urgent need for innovative ways to treat and prevent virulence caused by these pathogens. Many Gram-negative pathogenic bacteria use a type III secretion system (T3SS) to inject toxins and other effector proteins directly into host cells. The T3SS has become a popular anti-virulence target because it is required for pathogenesis and knockouts have attenuated virulence. It is also not required for survival, which should result in less selective pressure for resistance formation against T3SS inhibitors. In this review, we will highlight selected examples of direct antibody immunizations and the use of antibodies in immunotherapy treatments that target the bacterial T3SS. These examples include antibodies targeting the T3SS of Pseudomonas aeruginosa, Yersinia pestis, Escherichia coli, Salmonella enterica, Shigella spp., and Chlamydia trachomatis.

Intravenous Immune Globulin (IVIG) for Treatment of Autoimmune Heparin-Induced Thrombocytopenia: A Systematic Review

OBJECTIVE

To evaluate intravenous immune globulin (IVIG) for autoimmune heparin-induced thrombocytopenia (aHIT), including platelet recovery, IVIG dose, dosing weight, IVIG product used, and complications reported.

DATA SOURCES

PubMed and EMBASE were searched from inception through June 21, 2020. Search terms included heparin-induced thrombocytopenia, HIT, intravenous immune globulin, IVIG, autoimmune HIT, aHIT, and immune globulin.

STUDY SELECTION AND DATA EXTRACTION

Patients administered IVIG for HIT and diagnosed by immunoassay (optical density ≥2) or positive activation assay were included.

DATA SYNTHESIS

Twenty-four cases were reviewed; 92% had persistent aHIT. Time to IVIG administration post-nonheparin anticoagulant initiation was 9 days (median). Most common IVIG cumulative dose was 2 g/kg (dosed as 1 g/kg/d for 2 consecutive days); 75% had a favorable platelet increase (≥50 × 10⁹/L) within 5 days of initial IVIG dosing.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

aHIT is characterized by critically low platelets, thrombosis, and a persistent delay in platelet recovery despite treatment with a nonheparin anticoagulant. An immunoassay and subsequent confirmatory activation assay (at low, high, and 0 IU/mL unfractionated heparin levels) is recommended to confirm diagnosis. Patients nonresponsive to nonheparin anticoagulants within 5 days of initiation should be evaluated for IVIG treatment (2 g/kg cumulative dose). More data are needed to clarify appropriate IVIG dosing weight, although based on current published literature, it is recommended to use actual body weight.

CONCLUSIONS

Data reported support use of IVIG as adjunctive therapy for patients with aHIT. Judicious IVIG use based on key clinical and laboratory findings is critical.

KMP01D Demonstrates Beneficial Anti-inflammatory Effects on Immune Cells: An ex vivo Preclinical Study of Patients With Colorectal Cancer

Background: Colorectal cancer (CRC) is frequently associated with dysbiosis of the gut microbiome which, together with a compromised gut barrier, can result in perioperative endotoxin leakage into the circulation. Constant local and systemic inflammatory activity is suggested to facilitate metastases formation. Previous studies have pointed to the capacity of a colostrum preparation to neutralize endotoxins within the gastrointestinal tract which could ameliorate associated inflammatory responses and tumor recurrence in affected patients. This study aimed to examine the effects of the colostrum preparation, KMP01D, on the inflammatory activity of patient-derived immune cells. Methods: The effects of KMP01D on pro-/anti-inflammatory cytokine responses and apoptosis were examined ex vivo using immune cells from CRC patients (stages I-IV, n = 48). The expression of CD14, CD68, Toll-like receptor (TLR)4, and insulin-like growth factor (IGF)-1 was also analyzed. Results: KMP01D increased interleukin (IL)-10 and IL-13 anti-inflammatory cytokine expression in patient-derived peripheral blood mononuclear cells (PBMCs). Interestingly, KMP01D also decreased the secretion of IL-1β, IL-6, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-12 inflammatory cytokines, and IGF-1 in these cells. Moreover, CD14 and TLR4 expression involved in endotoxin signaling was downregulated in PBMCs and tumor-derived cells. Apoptosis of immune cells and tumor-derived cells was likewise enhanced with KMP01D. Addition of vitamin D3 as a cofactor demonstrated enhanced anti-inflammatory effects. Conclusions: KMP01D demonstrated beneficial ex vivo effects on inflammatory cytokine responses in PBMCs and enhanced apoptosis of immune cells from CRC patients. In line with previous clinical trials, we present new evidence endorsing KMP01D as a treatment strategy to regulate stage-dependent local and systemic inflammation in CRC patients.

Immunoglobulin for Treating Bacterial Infections: One More Mechanism of Action

The mechanisms underlying the effects of immunoglobulins on bacterial infections are thought to involve bacterial cell lysis via complement activation, phagocytosis via bacterial opsonization, toxin neutralization, and antibody-dependent cell-mediated cytotoxicity. Nevertheless, recent advances in the study of the pathogenicity of Gram-negative bacteria have raised the possibility of an association between immunoglobulin and bacterial toxin secretion. Over time, new toxin secretion systems like the type III secretion system have been discovered in many pathogenic Gram-negative bacteria. With this system, the bacterial toxins are directly injected into the cytoplasm of the target cell through a special secretory apparatus without any exposure to the extracellular environment, and therefore with no opportunity for antibodies to neutralize the toxin. However, antibodies against the V-antigen, which is located on the needle-shaped tip of the bacterial secretion apparatus, can inhibit toxin translocation, thus raising the hope that the toxin may be susceptible to antibody targeting. Because multi-drug resistant bacteria are now prevalent, inhibiting this secretion mechanism is an attractive alternative or adjunctive therapy against lethal bacterial infections. Thus, it is not unreasonable to define the blocking effect of anti-V-antigen antibodies as the fifth mechanism for immunoglobulin action against bacterial infections.

Transfusion-Related Acute Lung Injury due to Iatrogenic IVIG Overdose in Guillain-Barre Syndrome

Transfusion-related acute lung injury (TRALI) is a transfusion-related adverse effect associated with high mortality, manifesting with acute respiratory distress and with features of non-cardiogenic pulmonary edema. It is rarely reported following intravenous immunoglobulin (IVIG) infusion and is even rarer in pediatric population. We here present a 12-year-old female child who presented as a case of acute flaccid paralysis and was diagnosed clinically as Guillain-Barre syndrome. As per protocol, she was given IVIG for 4 of the 5 days therapy at the dose of 0.4mg/kg/day before the patient went to another hospital. Subsequently in the next 1 week, she received two more courses of IVIG in two different hospitals following which she developed respiratory distress and was again admitted in our hospital. A diagnosis of TRALI was leveled on clinical ground because of IVIG overdose. Patient subsequently improved on high-flow oxygen therapy and conservative management. This unfortunate case of iatrogenic IVIG overdose just reinforces the fact of proper documentation of treatment to avoid such mishap and also prompt diagnosis and management of this least recognized entity of TRALI.

Pathological consequences of anti-citrullinated protein antibodies in tear fluid and therapeutic potential of pooled human immune globulin-eye drops in dry eye disease

PURPOSE

To investigate the role of Anti-Citrullinated Protein autoantibodies (ACPAs) in the pathology of dry eye disease (DED) and the therapeutic potential of pooled human immune globulin-eye drops in these patients.

METHODS

We investigated the presence of citrullinated proteins and ACPAs in ocular surface wash (OSW) and conjunctival impressions from patients with DED and determined the pathological consequences of OSW with high ACPA using in vitro experiments and in vivo murine models. We performed a randomized, double-masked, pilot clinical trial to determine the safety, tolerability and preliminary efficacy of using pooled human immune globulin-eye drops to treat DED patients with ACPAs in OSW.

RESULTS

We found that neutrophils are a source of citrullinated proteins on the ocular surface of DED patients. We detected significantly higher immunoglobulin amount and presence of several species of ACPAs in OSW from DED patients. We also found that OSW with high ACPA contributes to production of NETs, and that ACPAs cause ocular surface disease in murine eyes, both of which are reduced with addition of Immune globulins. As compared to Vehicle treatment, pooled human immune globulin-eye drops (IVIG 4 mg/mL) twice a day for 8 weeks caused significant reduction in signs and symptoms of DED with no difference in tolerability or adverse events.

CONCLUSIONS

This is the first report demonstrating ACPAs in OSW of DED patients and their contribution to ocular surface disease. The first-in-human clinical trial suggests that pooled immune globulin-eye drops are a potential new class of biologic therapies for Dry Eye patients.

Czech Hizentra Noninterventional Study With Rapid Push: Efficacy, Safety, Tolerability, and Convenience of Therapy With 20% Subcutaneous Immunoglobulin

PURPOSE

Immunoglobulin substitution therapy is an essential therapeutic approach for patients with primary antibody deficiencies. Different methods of administration, including intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (SCIG) preparations, provide effective and tolerable treatment and enable the adjustment of therapy to patients' needs. A new 20% SCIG represents a new therapeutic option and a new route of administration using rapid-push application. The aim of the Czech Hizentra Noninterventional Study With Rapid Push (CHHINSTRAP) is to evaluate patient satisfaction with as well as the tolerability and efficacy of nonmedical switch to 20% SCIG from previous treatment with IVIG or SCIG and rapid push as a new way to administer SCIG. CHHINSTRAP is the first Phase IV, noninterventional, open-label, prospective, multicentric study of this type conducted in Central and Eastern Europe.

METHODS

Primary end points, including efficacy, adverse effects, convenience of use, and overall satisfaction, were evaluated by Treatment Satisfaction Questionnaire for Medication version II. Secondary end points, such as serum IgG trough levels, infusion duration, number of application sites, frequency of infections, related hospital admissions, and antibiotic consumption, were obtained from patients at each follow-up visit.

FINDINGS

Together, 50 eligible patients with primary antibody deficiency were switched from SCIG or IVIG to an equivalent dose of 20% SCIG and were followed up for 12 months during 5 consecutive visits. The results indicate that patients switched from previous IVIG or SCIG preparations had significantly higher serum trough IgG levels and a lower incidence of infections and related events, such as hospital admissions or consumption of antibiotics. These findings were also reflected in gradually increasing convenience of use and overall satisfaction reported by patients. Apart from duration of application, no differences were found between patients previously receiving SCIG or IVIG. Moreover, our study found a high level of safety of 20% SCIG rapid push, which was comparable to other preparations and application methods.

IMPLICATIONS

On the basis of the results of CHHINSTRAP study, we conclude that 20% SCIG is a tolerable and effective immunoglobulin preparation, representing a new therapeutic approach in patients with primary antibody deficiencies. Its efficacy and tolerability have been found in patients on nonmedical switch from previous treatment with IVIG or SCIG.

Common variable immunodeficiency patients display elevated plasma levels of granulocyte activation markers elastase and myeloperoxidase

Common variable immunodeficiency disorders (CVIDs) represent a group of primary immunodeficiency diseases characterized by hypogammaglobulinemia and dysfunctional immune response to invading pathogens. Previous studies have indicated that CVID is associated with microbial translocation and systemic myeloid cell activation.

The goal of this study was to determine whether patients with CVID display elevated systemic levels of markers of granulocyte activation and whether the levels are further influenced by intravenous immunoglobulin (IVIg) infusions. The plasma levels of granulocyte activation markers elastase and myeloperoxidase were determined using enzyme-linked immunosorbent assay (ELISA) in 46 CVID patients and 44 healthy controls. All CVID patients were in a stable state with no apparent acute infection. In addition, granulocyte activation markers’ plasma levels in 24 CVID patients were determined prior to and 1 h following IVIg administration. Neutrophil elastase and myeloperoxidase plasma levels were significantly higher in CVID patients than in healthy controls. Systemic elastase levels were further increased following IVIg administration. In vitro stimulation of 13 CVID patients’ whole blood using IVIg in a therapeutically relevant dose for 2 h resulted in a significant increase in plasma elastase levels compared to unstimulated blood. The data presented here indicate that CVID is associated with chronic granulocytic activation which is further exacerbated by administering IVIg. Increased myeloperoxidase and elastase levels may contribute to associated comorbidities in CVID patients.

The FcRn inhibitor rozanolixizumab reduces human serum IgG concentration: A randomized phase 1 study

Pathogenic immunoglobulin G (IgG) autoantibodies characterize some human autoimmune diseases; their high concentration and long half-life are dependent on recycling by the neonatal Fc receptor (FcRn). Inhibition of FcRn is an attractive new treatment concept for IgG-mediated autoimmune diseases. Rozanolixizumab (UCB7665; CA170_01519.g57 IgG4P) is an anti-human FcRn monoclonal antibody. In cynomolgus monkeys, rozanolixizumab reduced IgG (maximum 75 to 90% by about day 10), was well tolerated, and did not increase risk of infection. We also report a first-in-human, randomized, double-blind, placebo-controlled, dose-escalating study of intravenous (IV) or subcutaneous (SC) rozanolixizumab in healthy subjects (NCT02220153). The primary objective was to evaluate safety and tolerability. Secondary objectives were assessment of rozanolixizumab pharmacokinetics and pharmacodynamics, including effects on circulating IgG concentrations. Forty-nine subjects were randomized to receive rozanolixizumab (n = 36) or placebo (n = 13) across six cohorts. The first three cohorts received IV doses, and the subsequent three cohorts received SC doses, of rozanolixizumab 1, 4, or 7 mg/kg (n = 6 for each cohort; plus n = 7 or 6 for placebo, respectively). The most frequent treatment-emergent adverse event [TEAE; headache, 14 of 36 (38.9%) subjects] was dose-dependent and more prominent after IV administration. Severe TEAEs occurred in four subjects, all in the highest-dose IV group [headache (n = 3) and back pain (n = 1)]. Rozanolixizumab pharmacokinetics demonstrated nonlinear increases with dose. There were sustained dose-dependent reductions in serum IgG concentrations (IV and SC rozanolixizumab). These data provide clinical evidence for the therapeutic potential of rozanolixizumab.

Adverse Effects of Immunoglobulin Therapy

Immunoglobulin has been widely used in a variety of diseases, including primary and secondary immunodeficiency diseases, neuromuscular diseases, and Kawasaki disease. Although a large number of clinical trials have demonstrated that immunoglobulin is effective and well tolerated, various adverse effects have been reported. The majority of these events, such as flushing, headache, malaise, fever, chills, fatigue and lethargy, are transient and mild. However, some rare side effects, including renal impairment, thrombosis, arrhythmia, aseptic meningitis, hemolytic anemia, and transfusion-related acute lung injury (TRALI), are serious. These adverse effects are associated with specific immunoglobulin preparations and individual differences. Performing an early assessment of risk factors, infusing at a slow rate, premedicating, and switching from intravenous immunoglobulin (IVIG) to subcutaneous immunoglobulin (SCIG) can minimize these adverse effects. Adverse effects are rarely disabling or fatal, treatment mainly involves supportive measures, and the majority of affected patients have a good prognosis.

Anti-inflammatory intravenous immunoglobulin (IVIg) suppresses homeostatic proliferation of B cells

An intravenous injection of plasma-derived immunoglobulins is used for the treatment of severe infectious and autoimmune disorders. Despite of its clinical efficacy, precise mechanisms by which intravenous immunoglobulin (IVIg) suppresses proinflammatory immune response are still enigmatic. Here, we provide in vitro evidence that IVIg inhibits homeostatic proliferation of B cells accompanied by induction of their cell aggregation. The IVIg-driven suppression of B cell proliferation and induction of cell aggregation are both unaffected by treatment with a neutralizing antibody against low-affinity Fc receptors for IgG (CD16/FcγRIII and CD32/FcγRII), known cell surface ligands for IVIg. Our observations propose a new immunosuppressive action of IVIg, which directly acts on steady-state B cells to suppress their homeostatic expansion.