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).

Could Intravenous Immunoglobulin Collected from Recovered Coronavirus Patients Protect against COVID-19 and Strengthen the Immune System of New Patients?

The emergence of the novel coronavirus in Wuhan, China, which causes severe respiratory tract infections in humans (COVID-19), has become a global health concern. Most coronaviruses infect animals but can evolve into strains that cross the species barrier and infect humans. At the present, there is no single specific vaccine or efficient antiviral therapy against COVID-19. Recently, we showed that intravenous immunoglobulin (IVIg) treatment reduces inflammation of intestinal epithelial cells and eliminates overgrowth of the opportunistic human fungal pathogen Candida albicans in the murine gut. Immunotherapy with IVIg could be employed to neutralize COVID-19. However, the efficacy of IVIg would be better if the immune IgG antibodies were collected from patients who have recovered from COVID-19 in the same city, or the surrounding area, in order to increase the chance of neutralizing the virus. These immune IgG antibodies will be specific against COVID-19 by boosting the immune response in newly infected patients. Different procedures may be used to remove or inactivate any possible pathogens from the plasma of recovered coronavirus patient derived immune IgG, including solvent/detergent, 60 °C heat-treatment, and nanofiltration. Overall, immunotherapy with immune IgG antibodies combined with antiviral drugs may be an alternative treatment against COVID-19 until stronger options such as vaccines are available.

Naturally occurring autoantibodies against α-synuclein rescues memory and motor deficits and attenuates α-synuclein pathology in mouse model of Parkinson's disease

It has been suggested that aggregation of α-synuclein (α-syn) into oligomers leads to neurodegeneration in Parkinson's disease (PD), but intravenous immunoglobulin (IVIG) which contains antibodies against α-syn monomers and oligomers fails to treat PD mouse model. The reason may be because IVIG contains much low level of antibodies against α-syn, and of which only a small part can penetrate the blood-brain barrier, resulting in an extremely low level of effective antibodies in the brain, and limiting the beneficial effect of IVIG on PD mice. Here, we first isolated naturally occurring autoantibodies against α-syn (NAbs-α-syn) from IVIG. Our further investigation results showed that NAbs-α-syn inhibited α-syn aggregation and attenuated α-syn-induced cytotoxicity in vitro. Compared with vehicles, NAbs-α-syn significantly attenuated the memory and motor deficits by reducing the levels of soluble α-syn, total human α-syn and α-syn oligomers, decreasing the intracellular p-α-syn^ser129 deposits and axonal pathology, inhibiting the microgliosis and astrogliosis, as well as the production of proinflammatory cytokines, increasing the levels of PSD95, synaptophysin and TH in the brain of A53T transgenic mice. These findings suggest that NAbs-α-syn overcomes the deficiency of IVIG and exhibits a promising therapeutic potential for the treatment of PD.

Pathogen Safety of a New Intravenous Immune Globulin 10% Liquid

BACKGROUND

The manufacturing process of a new intravenous immune globulin (IVIG) 10% liquid product incorporates two dedicated pathogen safety steps: solvent/detergent (S/D) treatment and nanofiltration (20 nm). Ion-exchange chromatography (IEC) during protein purification also contributes to pathogen safety. The ability of these three process steps to inactivate/remove viruses and prions was evaluated.

OBJECTIVES

The objective of this study was to evaluate the virus and prion safety of the new IVIG 10% liquid.

METHODS

Bovine viral diarrhea virus (BVDV), human immunodeficiency virus type 1 (HIV-1), mouse encephalomyelitis virus (MEV), porcine parvovirus (PPV), and pseudorabies virus (PRV) were used as models for common human viruses. The hamster-adapted scrapie strain 263K (HAS 263K) was used for transmissible spongiform encephalopathies. Virus clearance capacity and robustness of virus reduction were determined for the three steps. Abnormal prion protein (PrP^Sc) removal and infectivity of the samples was determined.

RESULTS

S/D treatment and nanofiltration inactivated/removed enveloped viruses to below detection limits. IEC supplements viral safety and nanofiltration was highly effective in removing non-enveloped viruses and HAS 263K. Overall virus reduction factors were: ≥9.4 log₁₀ (HIV-1), ≥13.2 log₁₀ (PRV), ≥8.2 log₁₀ (BVDV), ≥11.7 log₁₀ (MEV), ≥11.6 log₁₀ (PPV), and ≥10.4 log₁₀ (HAS 263K).

CONCLUSION

Two dedicated and one supplementing steps in the manufacturing process of the new IVIG 10% liquid provide a high margin of pathogen safety.

Immunoglobulins and their use in children

Immunoglobulin preparations are one of the products of the human plasma fractionation, where the plasma is obtained, in accordance with WHO guidelines from at least 1,000 donors. These preparations contain all IgG subclasses with various antigen characteristics. In clinical practice these drugs are used as replacement therapy in patients with primary and secondary immunodeficiencies as well as immunomodulatory therapy in many autoimmune diseases and systemic inflammatory diseases. Here we present characteristics of i.v. polyvalent, human immunoglobulin preparations available on the Polish market and the possibilities of their use in clinical practice, in children with hematological diseases. Considering the very low consumption of immunoglobulin preparations in our country as compared to other European countries, we would like to draw the attention of medical professionals, especially pediatricians and haematologists, to the benefits that stem from the use of these drugs in the therapy of children with haematological diseases. Our work will also facilitate the choice of an optimal polyvalent human immunoglobulin preparation for a particular patient.

Idiotype-specific intravenous immunoglobulin (IVIG) for therapy of autoimmune diseases

Intravenous immunoglobulin (IVIG) is used successfully for therapy of inflammatory and autoimmune diseases, especially in cases of conventional therapy resistance. Within the broad spectrum of immunomodulatory activities of IVIG in vitro and in vivo, the anti-idiotypic activity, neutralizing the autoimmune disease related idiotypes, is one of the main mechanism. We and others have proven that from the IVIG composition, diverse fractions of autoimmune disease specific IVIG can be affinity purified (sIVIG). This sIVIG was shown to be more efficient than the whole compound of IVIG in experimental animal models of autoimmune diseases.The affinity purification of disease sIVIG encompasses three stages. The first stage is to construct an autoantigen column for affinity purification of the autoantibodies. In the second stage the purified autoantibodies are used to construct a new column composed of the autoantibodies. The later is utilized for affinity purification of anti-autoantibodies (anti- idiotypes) IVIG defined as autoimmune disease specific IVIG- sIVIG.

Preparation, purification and virus inactivation of intravenous immunoglobulin from human plasma

IVIG can be prepared from fractionation of normal human plasma and it is used as a therapeutic drug for treatment of various diseases. IVIG has been for some time the high-growth product within the plasma derived products, at both a global and a national country level. Fractionation was performed according to Cohn method with some modifications. Fraction II was first produced and then it was used for purification and virus inactivation steps. Two methods of virus inactivation (pasteurization at 60 degrees C for 10 hours and solvent/detergent treatment with TnBP and Tween 80) were used and validated. A chromatography method (cation exchange chromatography on CM Sepharose FF) was also added to obtain high purity. The final product (in liquid and freeze dried formulation) meets European Pharmacopeias requirements. The amount of PKA and aggregates was beyond the acceptance limit. The intactness of the IVIG was also examined by circular dichroism (secondary and tertiary structure). It was stable after 6 months of storage. Since Iran market is completely dependant on importation of plasma derived products, it is important to develop such methods for production of IVIG to obtain regional demands.

Economical impact of plasma fractionation project in Iran on affordability of plasma-derived medicines

In Iran all transfusion services are concentrated under authority of one public and centralized transfusion organization which has created the opportunity of using plasma produced in its blood centers for fractionation. In 2008 voluntary and non remunerated Iranian donors donated 1.8 million units of blood. This indicates a 25/1000 donation index. After responding to the needs for fresh plasma and cryoprecipitate each year about 150000 L of recovered plasma are reserved for fractionation. In an attempt to improve both blood safety profile and availability and affordability of plasma derived medicines, Iran's national transfusion service has entered into a contract fractionation agreement for surplus of plasma produced from donated blood by voluntary non remunerated donors. In order to ensure safety of product produced, Iran has chosen to collaborate with international fractionators based in highly regulated countries. The main objective of this study was to evaluate the impact of contract plasma fractionation on the affordability of the plasma derived medicines in Iran. During 2006-2008, Iran's contract fractionation project was able to produce 46%, 18% and 6% of IVIG, Albumin and FVIII consumed in Iran's market, respectively. In contrary to IVIG and Albumin, due to fairly high consumption of FVIII in Iran, the role of fractionation project in meeting the needs to FVIII was not substantial. However, Iran's experience has shown that contract plasma fractionation, through direct and indirect effects on price of plasma derived medicines, could substantially improve availability and affordability of such products in national health care system.

A new liquid intravenous immunoglobulin with three dedicated virus reduction steps: virus and prion reduction capacity

BACKGROUND AND OBJECTIVES

A new 10% liquid human intravenous immunoglobulin (US trade name: Gammagard Liquid; European trade name: KIOVIG) manufactured by a process with three dedicated pathogen inactivation/removal steps (solvent/detergent treatment, 35-nm nanofiltration and low pH/elevated temperature incubation) was developed. The ability of the manufacturing process to inactivate/remove viruses and prions was investigated.

MATERIALS AND METHODS

Virus and prion removal capacities were assessed with down-scale spiking experiments, validated for equivalence to the large-scale process.

RESULTS

Lipid-enveloped viruses were completely inactivated/removed by each of the three dedicated virus clearance steps, and for human immunodeficiency virus 1 (HIV-1) and pseudorabies virus (PRV), also by the upstream cold ethanol fractionation step. Relevant non-enveloped viruses [i.e. hepatitis A virus (HAV) and parvovirus B19 (B19V)] were effectively removed by nanofiltration and the cold ethanol fractionation step, and partial inactivation of non-enveloped viruses was achieved by low pH incubation. Overall log reduction factors were > 20.0 for HIV-1, > 18.1 for bovine viral diarrhoea virus, > 16.3 for West Nile virus, > 10.0 for influenza A virus subtype H5N1, > 21.8 for PRV, 12.0 for HAV, > 12.1 for encephalomyocarditis virus, 10.6 for B19V and 10.3 for mice minute virus. Prions (Western blot assay) were completely removed (> or = 3.2 mean log reduction) by a step of the cold ethanol fractionation process.

CONCLUSIONS

Introducing three dedicated virus-clearance steps in the manufacturing process of immunoglobulins from human plasma provides high margins of safety.

Self-Reactivity in the Dimeric Intravenous Immunoglobulin Fraction

Therapeutic intravenous immunoglobulin (IVIg) preparations contain antibodies reflecting the cumulative antigen experience of the donor population. IVIg contains variable amounts of monomeric and dimeric IgG, but there is little information available on their comparative antibody specificities. We have isolated highly purified fractions of monomeric and dimeric IgG by size-exclusion chromatography. Following treatment of all fractions at pH4, analyses by immunodot and immunocytology on human cell lines showed a preferential recognition of autoantigens in the dimeric IgG fraction. Investigation of the HEp-2 cytoplasmic proteome by 2D-PAGE, Western blot, and subsequent identification of IVIg reactive spots by mass spectrometry (LC-MS/MS) showed that IVIg recognized only a restricted set of the total proteins. Similar experiments showed that more antigens were recognized by the dimeric IgG fraction, especially when the dissociated dimer fraction was used, as compared to its monomeric counterpart. These observations are consistent with idiotype-anti-idiotype masking of auto-specific Abs in the dimeric fraction of IVIg.

A new liquid, intravenous immunoglobulin product (IGIV 10%) highly purified by a state-of-the-art process

BACKGROUND AND OBJECTIVES

The ultimate goal was to generate an industrial-scale process suitable to produce a high-yield, safe and stable immunoglobulin G (IgG) preparation for intravenous administration, which is ready to use for customer convenience. This new liquid 10% IgG preparation (IGIV 10%) was compared to Gammagard SD, a licenced lyophilized immunoglobulin in biochemical and preclinical testing.

MATERIALS AND METHODS

The new process, which includes three dedicated virus clearance steps, is a streamlined combination of the currently applied and well-established manufacturing procedures. The biochemical characterization is done by standard methods focusing on purity, integrity and functionality of the preparation. Efficacy is demonstrated in vivo by mouse protection testing and in vitro by opsonization and protein A affinity chromatography. Pharmacokinetics in rats is evaluated after a single intravenous dose. The anaphylactoid potential is determined in rats and in guinea pigs, while thrombogenicity is assessed in a rabbit model. The influence of the products on vital functions is tested on dogs, while acute toxicity studies are carried out on mice and rats.

RESULTS

The biochemical characterization data demonstrate the high purity of monomeric IgG in the product. The mouse protection test showed that the protective activity against systemic bacterial infections of IGIV 10% is at least as good as the reference Gammagard SD. This result is supported by the broad spectrum of antibodies in high titres against bacteria and viruses and the high functional integrity of the IgG molecule (> or = 90% functionally intact IgG) in IGIV 10%. The opsonic activity of all IGIV 10% lots is similar to the one of the reference Gammagard SD. In safety and thrombogenicity studies, no adverse effects of IGIV 10% were observed. Pharmacokinetic studies showed no statistically significant differences between the two products. In the acute toxicity animal studies, IGIV 10% compared favourably to the reference Gammagard SD.

CONCLUSIONS

The new manufacturing process enables the production of a highly purified IgG preparation for intravenous administration. The product has an IgG subclass distribution similar to plasma and contains a broad spectrum of functionally intact antibodies. Preclinical studies demonstrate that the liquid IGIV 10% combines excellent qualities of efficacy, safety and tolerability.

Pathogen inactivation and removal procedures used in the production of intravenous immunoglobulins

Patients with immunodeficiencies or some types of autoimmune diseases rely on a safe therapy with intravenous immunoglobulins (IVIGs) manufactured from human plasma, the only available source for this therapeutic. Since plasma is predisposed to contamination by a variety of blood-borne pathogens, ascertaining and ensuring the pathogen safety of plasma-derived therapeutics is a priority among manufacturers. State-of-the-art manufacturing processes provide a high safety standard by incorporating virus elimination procedures into the manufacturing process. Based on their mechanism these procedures are grouped into three classes: partitioning, inactivation, and virusfiltration.

International collaborative study to establish immunoglobulin (anti-D test) BRP batch 1

An international collaborative study was organised to establish a European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) and United States (US) Food and Drug Administration (FDA) reference preparation for the test for anti-D (anti-Rho) antibodies in human normal immunoglobulin for intravenous administration (IGIV). A candidate positive control (IGIV+anti-D) and negative control IGIV were compared to corresponding World Health Organization (WHO) International Reference Reagents using a direct haemagglutination reference method. Sixteen (16) laboratories participated in the collaborative study. Further to completion of the study, the materials assayed in the study were granted the status of Ph. Eur. and US FDA reference preparations for controlling the levels of anti-D in IGIV.

[Technology of immunoglobulin production. I. Technological aspects of purification]

Plasma-derived intravenous immunoglobulin (IVIG) preparations have become the major plasma products on the world blood product market due to the successful application for the prophylactic prevention of infectious diseases and replacement therapy in autoimmune and inflammatory diseases. In this review classical manufacturing processes as well as new chromatographic, membrane, and mixed industrial technologies are discussed with respect to the cost and amount of the final product of high quality and virus- and prion-safety which is to be obtained.

A modified caprylic acid method for manufacturing immunoglobulin G from human plasma with high yield and efficient virus clearance

BACKGROUND AND OBJECTIVES

The increasing demand for intravenous immunoglobulin (IVIG) necessitates the development of improved plasma fractionation methods, providing higher immunoglobulin G (IgG) recovery. Here, we describe a new IVIG production process resulting in a high yield of IgG and effective reduction of physico-chemically resistant viruses.

MATERIALS AND METHODS

IgG was purified from Cohn fraction II+III by caprylic acid treatment, polyethylene glycol precipitation, anion-exchange chromatography, nanofiltration and ultrafiltration. Stability of the purified IgG was studied in different formulations. Virus reduction was studied with two viruses: bovine viral diarrhoea virus, assessed by an infectivity assay; and human parvovirus B19, assessed by polymerase chain reaction.

RESULTS

The combination of caprylic acid treatment with polyethylene glycol precipitation and a single anion-exchange chromatography yielded polymer-free, pure IgG. The purified IgG could be filtered through a small pore-size virus filter (Millipore V-NFP) with high throughput and excellent yield. The formulated product was stable as a 100 g/l IgG solution. Bovine viral diarrhoea virus was effectively inactivated by the caprylic acid treatment, and parvovirus B19 was effectively removed in the polyethylene glycol precipitation and nanofiltration stages, the total reduction of parvovirus being approximately 14 log10.

CONCLUSIONS

The new process gives pure and stable IgG solution with an average yield of 4.8 g of IgG per kg of recovered plasma and has a very high capacity to remove even physico-chemically resistant viruses.

Purification of intravenous immunoglobulin G from human plasma – aspects of yield and virus safety

Plasma-derived intravenous immunoglobulin (IVIG) preparations have been successfully applied for the prophylactic prevention of infectious diseases in immunodeficient patients. In addition to its replacement therapy of primary and secondary antibody deficiencies, IVIG has found increased use in autoimmune and inflammatory diseases. IVIG has become the major plasma product on the global blood product market. The world wide consumption nearly tripled between 1992 and 2003, from 19.4 to 52.6 tons. Classical manufacturing processes of IVIG, but also new strategies for purification are discussed with respect to practicability and yield. Ethanol fractionation is still the basis for most IVIG processes, although isolation and purification of immunoglobulin G (IgG) by chromatography has gained ground. The efficiency of virus inactivation methods and virus removal techniques in terms of logarithmic reduction factors are analyzed, but also the IgG losses are taken into consideration. Some of these methods also have the ability to separate prions. High pathogen safety and high yields have become the dominant goals of the plasma fractionation industry.

Gamma irradiation of intravenous immunoglobulin

This paper describes gamma irradiation of a biotherapeutic product under conditions (the Clearant Process") that protect proteins and foster inactivation of viruses and other pathogens. The treated product was immunoglobulin paste from cold ethanol fractionation of human plasma, a process intermediate in the production of intravenous immunoglobulin (IGIV). The frozen paste was irradiated on dry ice to 45 kGy, conditions that inactivate > or = 4 log10 of non-enveloped viruses and > or = 6 log10 of enveloped viruses. When IGIV purified from the irradiated paste was characterized, no protein aggregation, fragmentation, oxidation or denaturation was detected and Fab functionality remained intact.

Hypotension with intravenous immunoglobulin therapy: importance of pH and dimer formation

Therapy with intravenous immunoglobulin preparations has been used effectively in a wide range of conditions. Although generally well tolerated, intravenous immunoglobulin preparations may be associated with transient hypotension in some patients. This study examined the role of different immunoglobulin G fractions in the development of intravenous immunoglobulin-induced hypotension in an anaesthetized rat model and assessed the effects of a new liquid immunoglobulin prepared at a low pH on both the formation of immunoglobulin G dimers and the development of hypotension. The effects of this new preparation in an experimental autoimmune encephalomyelitis model were also evaluated. Results from the haemodynamic studies indicated that immunoglobulin G dimers in polyclonal immunoglobulin G are responsible for the hypotensive events associated with some immunoglobulin preparations. They also showed that adjustment to an acidic pH results in the rapid dissociation of immunoglobulin G dimers and prevents the development of hypotension. Additional experiments demonstrated that only immunoglobulin G dimers with a functional Fc fragment can bind to Fcgamma receptors on macrophages to induce the release of blood pressure-lowering mediators. Moreover, essentially monomeric Fc fragments can block the blood pressure-lowering effects of immunoglobulin G dimers. Preparation of a new liquid intravenous immunoglobulin with the pH adjusted to 4.3 prevents the formation of immunoglobulin G dimers even over long-term storage and does not significantly affect blood pressure in a rat model. This preparation is as effective as other intravenous immunoglobulin preparations in ameliorating symptoms of experimental autoimmune encephalomyelitis. These results, like those from previous studies, indicate that preparation of intravenous immunoglobulin at a low pH substantially reduces immunoglobulin G dimerization; this effect significantly decreases the potential for intravenous immunoglobulin to induce hypotension without reducing its clinically relevant biological activity.

Comparison of the efficacy of IGIV-C, 10% (caprylate/chromatography) and IGIV-SD, 10% as replacement therapy in primary immune deficiency. A randomized double-blind trial

A novel method of large-scale chromatography has been developed to improve recovery and purity of immunoglobulin G (IgG) from pooled plasma. The current study compares safety, toxicity and efficacy of two intravenous immunoglobulin products: a novel formulation, IGIV caprylate/chromatography (IGIV-C; Gamunex, 10%) and a licensed solvent/detergent-treated product, Gamimune N, 10% (IGIV-SD). The study, a randomized, double-blind, parallel group, therapeutic equivalence trial, was conducted at 25 treatment centers in Canada and the United States. Patients (n=172) having confirmed chronic primary immunodeficiency (PID), aged 1-75 years, and receiving IGIV therapy were enrolled. For 9 months, patients were treated with IGIV-C or IGIV-SD in accordance with the patient's individualized treatment regimen utilized before study entry. The primary endpoint was the proportion of patients with >or=1 validated acute sinopulmonary infection during the treatment period. Secondary endpoints included the proportion of patients with all infections, time to first infection, annual infection rates, lung function parameters, infusion-related safety and viral safety. The annual validated infection rate in the IGIV-C group was 0.18 compared to 0.43 in the IGIV-SD group (p=0.023). Nine patients receiving IGIV-C experienced validated infections, compared to 17 patients in IGIV-SD group (p=0.06). Acute sinusitis (validated plus clinically defined) was less frequent in the IGIV-C group (p=0.012). Presence of bronchiectasis did not affect efficacy. Adverse reactions were similar in frequency and severity in both groups. No evidence of viral transmission was observed. IGIV-C appears to be superior to IGIV-SD in preventing validated sinopulmonary infections, especially acute sinusitis, in patients with PID.

Evaluation of depth filtration to remove prion challenge from an immune globulin preparation

BACKGROUND AND OBJECTIVES

Plasma-derived therapeutic proteins have the potential to contain transmissible spongiform encephalopathy (TSE) infectivity. This study evaluated the effectiveness and characterized the mechanism of abnormal prion protein removal during a depth-filtration step used in the manufacture of an immunoglobulin preparation.

MATERIALS AND METHODS

Scrapie brain homogenate was treated with lysolecithin, sonicated and sequentially filtered through 0.45-, 0.22- and 0.1-microm membrane filters. The scrapie brain homogenate was then added (at a 1:51 dilution) to the Supernatant III fraction used in the manufacture of Rho(D) immune globulin (human). The spiked immunoglobulin preparation was then filtered through a depth filter under the same conditions used in full-scale production. After filtration, the depth filter was washed with hypertonic NaCl solutions to elute the abnormal prion protein (PrPSc) from the filter. A Western blot assay for PrPSc was used to quantify removal from the filtrate and recovery from the filter washes. A second run was performed whereby the PrPSc-spiked Supernatant III was filtered through a 0.22-microm membrane filter prior to depth filtration. A third run evaluated depth filtration of PrPSc in Tris-buffered saline (TBS).

RESULTS

The depth filter removed greater than four logs of PrPSc from the Supernatant III filtrate. A significant portion of the PrPSc could be recovered from the depth filter by elution with high-molarity NaCl solutions. Prefiltration (through a 0.22-microm membrane filter) of the spiked Supernatant III prior to depth filtration removed all detectable PrPSc. Depth filtration removed less than one log of PrPSc from TBS.

CONCLUSIONS

Depth filtration appears to remove PrPSc from the immunoglobulin preparation by mechanical straining rather than by adsorption to the filter matrix. The immunoglobulin preparation caused the PrPSc to aggregate from particles <0.1 microm in size to particles of >0.22 microm, probably as a result of the presence of methanol in the preparation. The depth filter failed to remove PrPSc from a purely aqueous environment.

Anti-idiotypes to oxidized LDL antibodies in intravenous immunoglobulin preparations--possible immunomodulation of atherosclerosis

OBJECTIVE

The aim of this study was to examine whether intravenous immunoglobulin (IVIg) preparations contain anti-oxLDL and anti-anti-oxLDL antibodies.

BACKGROUND

Oxidized low-density lipoprotein (oxLDL) is one of the major players in atherogenesis. IVIg can reduce atherosclerosis in experimental animal models.

METHODS

Six commercial IVIg preparations were tested for the presence of anti-oxLDL antibodies by EIA. Inhibition studies were performed with the different IVIg preparations and IgGs purified from a pool of sera from patients with high anti-oxLDL antibody levels. Absorption assays were carried out to evaluate the presence of anti-idiotypes against anti-oxLDL antibodies in IVIg preparations.

RESULTS

IVIg preparations tested had various degrees of reactivity towards oxLDL. Absorption experiments suggested that the reactivity was specific because it could be effectively absorbed by oxLDL and not by an irrelevant antigen PPD. The reactivity was smaller than that observed with the IgG from the pool with high anti-oxLDL antibody levels. Inhibition studies with IVIg demonstrated 20-45% inhibition of anti-oxLDL binding to oxLDL, compared to 76% inhibition by the pool with high anti-oxLDL levels. To investigate the presence of anti-idiotypes against anti-oxLDL antibodies within IVIg, F(ab')2 fragments of IVIg IgG were used to absorb IgG F(ab')2 fragments from the pool of sera with high anti-oxLDL levels. The decreased binding to oxLDL of the absorbed supernatants shows that IgG F(ab')2 fragments of the IVIg preparations had high inhibitory capacities ranging from 65 to 90%.

CONCLUSIONS

IVIg preparations contain both anti-oxLDL and anti-anti-oxLDL activity. This finding may explain the immunomodulating effect of IVIg in atherosclerosis.

Clinical efficacy and safety of a novel intravenous immunoglobulin preparation in adult chronic ITP

Use of intravenous immunoglobulins (IVIGs) is a well-established therapy in patients with acute or chronic autoimmune thrombocytopenic purpura (ITP). The aim of the present open, prospective study was to investigate efficacy and safety of the novel IVIG preparation BT681 (Biotest Pharma GmbH, Dreieich, Germany) in adult patients with chronic ITP (cITP). In order to fulfil high standards of purity and viral safety, an additional HPLC step has been introduced and validated virus removal and inactivating procedures are included in the manufacturing process of BT681. A total of 24 patients with platelet counts between 3/nl and 27/nl received a total dose of 2 g/kg body weight BT681 in standard dosage regimens: 1.0 g/kg/day for 2 days in 15 patients and 0.4 g/kg/day for five consecutive days in nine patients. Platelet response (platelet count > or =50/nl) and regression of haemorrhages were documented during the 28 days study period and safety parameters including adverse events, laboratory investigations and vital signs were regularly monitored. The overall response rate was 91.7%, that is 22/24 patients responded to BT681 treatment. The median time to platelet response was 3.0 days, the duration of response 25.5 days; the median max. platelet count 222/nl and the time to max. platelet count 7.5 days. During the entire observation period, platelet counts below baseline were only observed in five responders; in half of the patients, platelet counts were even above 50/nl at the end of follow-up. Corresponding to the good platelet response, the clinical symptoms improved markedly in the majority of patients within the first week after start of BT681 infusions with 88.9% overall regression of haemorrhages in comparison with baseline. The evaluation of platelet parameters showed a slight tendency in favour of the 5 days group, evaluation of haemorrhage severity slight advantages for the 2 days group. The adverse event data indicate that the therapy with BT681 was safe and well tolerated in both treatment groups even if minor effects were more frequent in patients treated with the 2 days regimen. The large majority of adverse events were known intolerabilities during the treatment phase described as mild and transient. The results demonstrate that the new immunoglobulin preparation BT681 is effective and safe in the treatment of adult patients with cITP.

Efficacy of IVIG affinity-purified anti-double-stranded DNA anti-idiotypic antibodies in the treatment of an experimental murine model of systemic lupus erythematosus

Since the idiotypic network is an important mechanism for controlling the immune repertoire, we tested anti-idiotypic modulation employing concentrated specific natural polyclonal anti-double-stranded (ds) DNA anti-idiotypic antibodies obtained from a commercial IVIG in the treatment of experimental systemic lupus erythematosus (SLE). Specific natural polyclonal anti-dsDNA anti-idiotypic antibodies (IVIG-ID) were affinity purified from IVIG on an anti-dsDNA-Sepharose column constructed from anti-dsDNA idiotypes (ID) affinity purified from 55 patients with active SLE. NZB/W F(1) mice were treated i.v. with 3 weekly injections of IVIG-ID (2 mg/kg/injection) or regular IVIG (400 mg/kg/injection) both before (age 8 weeks) and after developing anti-dsDNA antibodies at the age of 21-22 weeks. The IVIG-ID-treated mice showed a decline in the titer of anti-dsDNA antibodies during the treatment, reaching maximum suppression 1 week after the last injection. A significant difference in the proteinuria level in the IVIG-ID-treated group compared to the control group was observed. Immunohistology showed different patterns of IgG deposition, with mesangial and capillary wall deposits in controls and in the IVIG-treated group, but only mesangial deposits in the IVIG-ID-treated group. The survival time of the IVIG-ID-treated group was longer than the IVIG-treated group. Treatment with concentrated specific anti-dsDNA anti-ID prepared from commercial IVIG is more effective in suppressing the humoral reaction and clinical signs of SLE than native IVIG. These results point to the considerable regulatory role of anti-ID in the mechanism of action of IVIG in SLE.

Polychlorinated biphenyls and organochlorine pesticides are eliminated from therapeutic Factor VIII and immunoglobulin concentrates and reduced in albumin by plasma fractionation

BACKGROUND AND OBJECTIVES

Persistent organochlorine pollutants, such as polychlorinated biphenyls (PCBs) and organochlorine pesticides, are found in the general population and tend to accumulate in blood and tissues. Their distribution was examined in the starting plasma pools for fractionation, Cohn plasma fractions and therapeutic concentrates.

MATERIALS AND METHODS

In each process fraction, total protein, cholesterol and triglycerides were measured as well as organochlorine pesticides and PCB congeners.

RESULTS

Organochlorine compounds were undetectable in cryoprecipitate, Cohn fraction I, Factor VIII and immunoglobulin concentrates, and reduced in albumin preparations.

CONCLUSION

Cohn plasma fractionation is very efficient for removing pollutants present in the starting material. Biological processing techniques should be analysed for their capacity to eliminate/reduce persistent organochlorine pollutants from the therapeutic proteins.

Ensuring the pathogen safety of intravenous immunoglobulin and other human plasma-derived therapeutic proteins

Countless patients and clinicians rely on therapeutic proteins, such as intravenous immunoglobulins (IVIGs), isolated from human blood plasma. Since plasma is predisposed to contamination by a variety of blood-borne pathogens, ascertaining and ensuring the pathogen safety of plasma-derived therapeutics is a priority among manufacturers. Even though the pathogen safety records for IVIG and other plasma proteins are excellent, the industry remains active in research programs aimed at improving the margin of safety. Industry initiatives designed to increase the safety of plasma-derived products range from donor screening and testing to implementing methods into the manufacturing processes that can inactivate or remove pathogens from product streams. In general, the industry's comprehensive strategy is designed to provide patients and caregivers with the safest plasma products possible.

Solvent/detergent treatment does not alter the tolerance or uptake of human normal immunoglobulin for intramuscular injection

BACKGROUND AND OBJECTIVES

The tolerability and pharmacokinetics of a solvent/detergent-treated intramuscular immunoglobulin were compared with those of the standard product.

MATERIALS AND METHODS

Single, 750-mg intramuscular (i.m.) injections were administered to a total of 36 healthy individuals: 23 in a double-blind trial and 13 in an open trial. Changes in specific serum hepatitis A and hepatitis B antibodies were monitored for a period of up to 3 months postinjection.

RESULTS

No serious adverse reactions were reported, and the bioavailability of the solvent/detergent-treated preparation was equivalent to that of the standard i.m. immunoglobulin.

CONCLUSION

There is no evidence that solvent/detergent treatment alters the pharmacokinetics or tolerance of human normal immunoglobulin, but it offers additional assurance against potential virus transmission.

Clinical use of intravenous immunoglobulins

Prophylaxis and treatment with i.v. immunoglobulins must envisage preparations from normal or hyperimmunised human donors, animals (horses and rabbits) as well as monoclonal and genetically and proteomically engineered chimeric or recombinant antibodies. The latter group of antibody sources from the bioreactor source must be seen in the context of traditional antibody therapy, including passive immunization, general antibody substitution and provision of lost immune regulatory capacities such as downregulation of complement activation, attenuation of Fc receptor apparatus as well as anti-idiotypic potential. Beyond summarizing the present evidence based indications the present review is an outlook at the doorstep for future possibilities to improve precision of antibody dependent treatments and avoiding side effects which formerly compromised widespread use.

GB virus C/hepatitis G virus and intravenous immunoglobulins

BACKGROUND AND OBJECTIVES

Different intravenous immunoglobulins (IVIGs) were found to be GB virus C/hepatitis G virus polymerase chain reaction (GBV-C/HGV-PCR)-positive. The potential transmission of this virus to recipients by a PCR-positive IVIG batch was investigated.

MATERIALS AND METHODS

Polyclonal IVIGs of different manufacturers and with different virus inactivation procedures were analyzed by GBV-C/HGV-PCR and anti-E2-ELISA. Follow-up sera of 13 participants of a clinical trial performed with a GBV-C/HGV-PCR-positive batch were retrospectively investigated for GBV-C/HGV seroconversion (specific antibodies, viral RNA).

RESULTS

Four out of ten IVIGs analysed by GBV-C/HGV-PCR were - at least for some batches - virus genome-positive. Virus inactivation by solvent/detergent treatment resulted in GBV-C/HGV-PCR-negative products. GBV-C/HGV-specific antibodies were detectable in all IVIGs analyzed. There was no transmission of GBV-C/HGV observed when recipients of a large amount of a GBV-C/HGV-PCR-positive batch were analyzed by an antibody test and specific PCR.

CONCLUSIONS

Despite PCR positivity of an IVIG preparation no transmission of GBV-C/HGV to recipients was observed. Possible explanations are a sufficient virus inactivation procedure and/or presence of specific antibodies in the final products.

Human intravenous immunoglobulin preparation and virus inactivation by pasteurization and solvent detergent treatment

Human intravenous immunoglobulin (IVIG) solutions were prepared by two different methods and compared to each other. The crude immunoglobulin fraction obtained from Cohn-Oncley fractionation of plasma was further purified and subjected to virus inactivation, either by polyethylene glycol precipitation and pasteurization at 60 degrees C for 10 hours, or by ion exchange chromatography and solvent/detergent treatment. The final preparations, formulated in 5% immunoglobulin solutions were characterized by in vitro analyses of biochemical and biological properties and compared with the samples of other manufacturer's IVIG solution products. The critical properties evaluated in this study were purity, molecular intactness, and the biological functions such as Fc function and anticomplementary activity. Virus inactivation and removal by processing steps and by deliberate virucidal steps, as described above, were tested on various human pathogenic viruses, such as human immunodeficiency and experimental model viruses. The tested viruses were successfully inactivated and removed. We conclude that the intravenous immunoglobulins prepared by two different methods, as described above, provide an equivalent viral safety and quality.

[Inactivation of BVDV (experimental model for hepatitis C) using low pH and heat treatment in intravenous human immunoglobulins]

PURPOSE

To measure the capability of heat (60 degrees C for 10 hr) and low pH to inactivate BVDV (a model of HCV) in human intravenous immunoglobulins.

MATERIALS AND METHODS

The study was carried out on three batches of immunoglobulins produced by the Cohn method and contaminated with a known amount of BVDV. These mixtures, with and without 33% sorbitol, were submitted to heat treatment at 60 degrees C for 10 hours. The same immunoglobulin batches were manufactured at pH 4.25 and 4.5 and stored at 4 degrees C and 4 degrees C and 21 degrees C for 28 days. Samples of the two experiments were taken at the beginning and the end. The viral infectiousness was calculated by the standard microtiration method in 96-well plates, using the CPE, and the reduction factor was measured for each experiment.

RESULTS

Complete viral inactivation was achieved with the heat treatment after 4 hours, and the 33% sorbitol decreased the formation of aggregates. Treatment by pH 4.5, at 21 degrees C for 28 days, decreased the viral load by approximately 2 log; no viral inactivation was achieved in samples stored at 4 degrees C.

CONCLUSION

Heat is an effective method for inactivating HCV in final batches of human intravenous immunoglobulins when 33% sorbitol is added. The use of low pH at 21 degrees C as a method of viral inactivation must be evaluated case by case, since, according to the present results, it only achieved a 2 log inactivation.

Virus reduction in the preparation of intravenous immune globulin: in vitro experiments

BACKGROUND

While immune globulins for intravenous administration (IGIV) have an excellent record with respect to virus safety, concern regarding these preparations has been raised by reports of transmission of hepatitis C virus (HCV) to patients treated with IGIV and the presence of genetic material for HCV in IGIV preparations.

STUDY DESIGN AND METHODS

This in vitro study evaluated the effectiveness of several manufacturing steps, including ethanol precipitation and pasteurization, in reducing HIV and model viruses including encephalomyocarditis (EMC) virus, pseudorabies virus (PRV), bovine viral diarrhea virus (BVDV), Sindbis virus, vaccinia virus, and vesicular stomatitis virus (VSV), as well as HCV RNA, in IGIV.

RESULTS

Ethanol precipitation carried out after pasteurization resulted in virus reductions (log10) of >3.97 for HIV, 1.95 for EMC virus, >5.39 for PRV, and 3.52 for BVDV. Pasteurization inactivated EMC virus by 4.52 log10 and resulted in a log10 reduction of >6.54 for HIV, >5.39 for PRV, >6.64 for BVDV, >7.78 for Sindbis virus, >5.84 for vaccinia virus, and >6.99 for VSV. All viruses except EMC virus were reduced below the limit of detection within 6 hours of the beginning of pasteurization. Cohn processing of Fraction II + III paste and the 4.5-percent alcohol precipitation step prior to pasteurization provided additional virus removal. Studies using the polymerase chain reaction technique found that HCV RNA was detectable in the starting fraction of Cohn Fraction II paste, but not in the final IGIV preparation.

CONCLUSION

These findings strongly support the viral safety of IGIV prepared by this method and show a significant added measure of virus safety associated with pasteurization of this preparation.

Removal of viruses from human intravenous immune globulin by 35 nm nanofiltration

Viral safety is an important prerequisite for clinical immunoglobulin preparations. A common manufacturing practice is to utilize several virus removal/inactivation process steps to ensure the safety of human intravenous immunoglobulin (IVIg). In this regard, we examined the use of Planova 35 nm filters to reduce potential loads of both non-enveloped and enveloped viruses prior to end-stage solvent detergent treatment. The nanofiltration process was validated for removal of a variety of enveloped and non-enveloped viruses ranging in size from 70 nm to 18 nm including: Sindbis virus, Simian Virus 40 (SV40), Bovine Viral Diarrhoea virus (BVDV), Feline Calicivirus, Encephalomyocarditis virus (EMC), Hepatitis A virus (HAV), Bovine Parvovirus (BPV) and Porcine Parvovirus (PPV). The filtration procedure was carried out by first spiking a 7% solution of IVIg with < 10(8) virus. The spiked IVIg solution was then filtered through a 75 nm Planova filter followed by two Planova 35 nm filters in series (75/35/35). The 75 nm prefilter is incorporated into this process to increase the capacity of the 35 nm viral removal filters. As a result of the inclusion of the 75 nm pre-filtration step it was possible to assess the removal of virus by the 35 nm filters independent of possible aggregation of the initial viral spiking material. Samples were collected at each step and immediately titred by viral plaque assay. A process control sample of the spiked load solution was held at the same conditions for the duration of the filtration process and then titred to determine the extent to which antibody neutralization may have contributed to overall viral reduction. Control assays of spiked IVIg were performed to establish the degree of toxicity of the IVIg solution to the indicator cell lines and the extent to which the IVIg interfered with plaque formation in the assay system. This combined data was used to establish assay sensitivity for the calculation of log removal by the filtration process. It was noted that toxicity/interference effects could have a significant effect upon apparent log reductions, and these effects could vary greatly, even within viruses of the same family. The results of these studies indicate that 35 nm filtration is very effective for removing substantial quantities of both non-enveloped and enveloped viruses from IVIg. Complete clearance (to the limits of detection of the assay) was obtained for all viruses larger than 35 nm. Interestingly, viruses reported to have mean diameters of less than 35 nm (EMC and HAV) were at least partially removed by the filtration (4.3 and > 4.7 logs removal, respectively). Even small viruses such as PPV were to some extent removed from the IVIg solution by the filters (2.6 logs removal). Reduction of BPV would not be assessed due to extensive neutralization and interference with plaque formation by the IVIg. Sindbis and SV40 also were subject to neutralization and assay interference due to the IVIg, though to a lesser extent. We conclude from these studies that the 35 nm mean pore size is functionally efficient in removal of smaller size viruses from spiked IVIg concentrates.

New methods for inactivation of lipid-enveloped and non-enveloped viruses

Two new methods are described for inactivating lipid-enveloped and non-enveloped viruses in plasma-derived products such as coagulation factors and intravenous immunoglobulin (IGIV). Iodine/Sephadex delivers iodine to IGIV solutions in a slow, controlled way and allows for inactivation of > or = 4 logs of porcine parvovirus (PPV), a hardy non-enveloped virus, under conditions which do not measurably damage the structural or functional properties of the IGIV, and with essentially no iodination of the protein. All detectable enveloped and non-enveloped viruses were inactivated by this treatment. Gamma irradiation has been successfully used to inactivate viruses at the final vial stage in freeze-dried plasma proteins. Four logs of PPV were inactivated by irradiation in the presence of fibrinogen, factor VIII and alpha 1-proteinase inhibitor (API) at doses of 23, 28 and 30 kiloGray (kGy) respectively, while retaining 93% of fibrinogen solubility, 67% of factor VIII activity and over 80% of API activity. Bovine viral diarrhea virus (BVDV), a lipid-enveloped model for hepatitis C virus, was completely inactivated by radiation doses of 20-30 kGy in these products. Gamma irradiation was less effective in inactivating viruses in freeze-dried IGIV.

Research and development commitments in an integrated plasma collection and plasma fractionation environment

Plasma fractionation has emerged as one of the most scientifically demanding fields in the biopharmaceutical area. Producing safe plasma derivatives implies the development, use, and proper understanding of sensitive testing technologies to detect infection markers in starting plasma. It also requires the implementation of carefully selected, nondenaturing, efficient plasma protein purification and viral reduction technologies that do not alter the physiological functions and clinical potential of plasma proteins. Success in this field can be achieved only by a strong commitment to sustain constant research and development of projects targeting the production of safer and innovative plasma products.

New peptide and protein drugs

A view is presented on a number of recent developments, the present state and the perspectives, especially from a pharmacotherapeutic viewpoint, for peptide and protein drugs. The expanding use and the increasing experience create new pharmacotherapeutic modalities. Peptide and protein drugs comprise among others proteins isolated from human sources, and peptides and proteins made by biotechnology including monoclonal antibodies, recombinant human hormones, cytokines and growth factors. In the field of vaccine development also innovation is taking place. Optimal application schemes of these drugs may not have been reached and (clinical) pharmacists should contribute to the optimization. Since recombinant technology has abolished scarcity for a number of these drugs--especially 'physiological' substances--special ethical problems regarding an unlimited application or expansion of the indications may arise.

Clinical experience with Octagam, a solvent detergent (SD) virus inactivated intravenous gammaglobulin

OBJECTIVE

The safety and efficacy of Octagam, a solvent detergent (SD) virus inactivated intravenous gammaglobulin, were evaluated in 54 patients who received 301 infusions of Octagam for a total amount of 9301 grams, during 24 months.

METHODS

Adverse reactions during and after Octagam infusion were carefully recorded. Serum IgG and ALT levels were recorded monthly. Antibodies to HIV, HBV and HCV were recorded every 3 months.

RESULTS

In 22 chronic lymphocytic leukemia patients and 4 multiple myeloma patients, the monthly infusion of 0.4 gr/ kg Octagam proved safe and effective in increasing IgG levels and potentially reducing the rate of serious bacterial infections. In 20 patients with ITP, infusion of 2 gr/kg of Octagam was safe and effective in increasing the platelet count and in arresting spontaneous bleeding or preventing bleeding prior to surgical procedures. In 8 patients with the antiphospholipid syndrome monthly infusions of Octagam were found to be safe. Adverse reactions following Octagam infusion were uncommon, generally mild and all were transient. Viral safety assays for HIV, HBV and HCV were all negative.

CONCLUSION

Octagam is a safe intravenous gammaglobulin effective in patients with secondary hypogammaglobulinemia and ITP.

Liquid pasteurization of an immunoglobulin preparation without stabilizer: effects on its biological and biochemical properties

Intravenous immunoglobulins (IVIg) purified by cold ethanol fractionation have a very good safety record with regard to the transmission of many viruses. However, a few cases of non-A-non-B hepatitis have been described after intravenous injection of some immunoglobulin preparations. To ensure even higher safety for our IVIg, an additional virus inactivation step, based on pasteurization, was developed. The heating of aqueous IVIg was performed without stabilizer, and at a very low salt concentration (< 1 mM) at acidic pH. No generation of polymer was detected after pasteurization and a significant decrease in the proportion of dimers was observed. Analysis of the secondary structure by circular dichroism showed a very slight change in the secondary structure. The biological properties of the Fc region as well as the Fab region were not affected by the pasteurization. Our method has several advantages: (1) improvement of viral safety; (2) there is no need to add stabilizer which may stabilize viral particles, and (3) the absence of any hypotensive effect and low anticomplementary activity indicates a good clinical tolerance of IgG preparation.

Tolerability and kinetics of a solvent-detergent-treated intravenous immunoglobulin preparation in hypogammaglobulinaemia patients

The tolerability and kinetics of a solvent-detergent-treated 6% intravenous immunoglobulin (IVIG) preparation were studied in 15 hypogammaglobulinaemia patients during 3-4 regular substitution infusions of 9-48 g, the mean dose being 359 mg/kg. The infusions were well tolerated, and the trough serum IgG levels achieved were comparable to two commercial IVIG preparations. The stepwise increase of the infusion rate up to 5 mg/kg/min and the use of this IVIG as a 12% solution were possible without serious adverse events in all the 6 studied hypogammaglobulinaemia patients. This greatly reduced the time needed for the infusions.

Variable region-connected, dimeric fraction of intravenous immunoglobulin enriched in natural autoantibodies

The beneficial effect of intravenous immunoglobulin (IVIg) therapy in patients with autoimmune diseases is at least partially dependent on the content in IVIg of antibodies capable of interacting with variable regions (idiotypes) of autoantibodies. In the present study, we have evaluated the antibody activity to a panel of self and environmental antigens of IVIg preparations and their dimer-enriched fractions. Dimers were either obtained by affinity chromatography of IVIg on Sepharose-bound F(ab')2 fragments of IVIg or by size exclusion gel filtration chromatography of IVIg. Enrichment of IVIg in dimers was found to be associated with an increase in the antibody activity against self-antigens as compared with unchromatographed IVIg. Our findings extend previous observations on enhanced autoantibody content of the affinity chromatography-separated 'connected' fraction of IVIg and suggest that therapeutic preparations of IVIg enriched in dimers may be obtained by size exclusion chromatography. Separation by size increases the feasibility of industrial-scale preparation of IVIg with high dimer content that are endowed with high potential immunomodulatory activity in vivo.

Clinical experience with the viral safety of immunoglobulins

Preparations of intramuscular immunoglobulins (IMIGs) have not been reported to transmit viral disease since the inclusion of third-generation tests screening donor blood for hepatitis B virus. IMIGs and intravenous immunoglobulins (IVIGs) have never been a source of transmission of human immunodeficiency viruses. One episode of hepatitis B transmission by IVIGs caused by the addition of contaminated material during the manufacturing process, has been reported. Between 1983 and 1994 there were at least 17 reports of transmission of non-A, non-B hepatitis or [transaminitis' connected with the application of six IVIG preparations. These preparations were produced without including a validated virus-inactivation method in the manufacturing process. Careful analysis of these accidents demonstrates that minimization of virus contamination of source plasma, guarantee of good manufacturing practice, as well as application of an accepted virus-inactivation procedure are essential requirements for the production of safe immunoglobulin preparations.

Antibody Fc functional activity of intravenous immunoglobulin preparations treated with solvent-detergent for virus inactivation

We report here results of in vitro comparisons of the Fc functional activity of a second-generation intravenous immunoglobulin (IGIV) preparation (Venoglobulin-I) and a third-generation IGIV product that includes a deliberate virus-inactivation step (Venoglobulin-S). Both formulations showed equivalent Fc-mediated function against viral antigens (rubella, influenza A, and influenza B) by single-radial hemolysis test, and against group B Streptococcus, Staphylococcus aureus and Escherichia coli by opsonophagocytosis assay. In addition, we showed by three different immunochemical reactions and by HPLC analysis that both preparations consisted of mostly monomeric IgG and contained very low levels of complement-fixing IgG aggregates. However, IgG aggregation induced by heating at 63 degrees C markedly enhanced fixation of Clq and C3 and binding to Raji cells, indicating that the IgG molecules retained their complement-fixing capacity. Thus, the incorporation of a virus inactivation step in the manufacture of our third-generation IGIV did not alter the Fc functional activities of the IgG, as measured by these in vitro assay systems.

Inactivation and elimination of viruses during preparation of human intravenous immunoglobulin

We report here the results of our evaluation of virus inactivation during the manufacturing steps of two intravenous immunoglobulin (IGIV) preparations. Virus inactivation and/or removal by processing steps, such as ethanol fractionation and polyethylene glycol precipitation, and deliberate virucidal steps, such as solvent/detergent treatment and pasteurization, were tested on a variety of human pathogenic and experimental model viruses, including human immunodeficiency, Hepatitis C, Mumps, Vaccinia, Chikungunya, Vesicular Stomatitis, Sindbis, and ECHO viruses. All viruses were successfully inactivated and/or eliminated by the processing steps studied. In some cases, however, multiple steps were required. We conclude that the incorporation of steps deliberately designed to inactivate or remove viruses during the production of IGIV provides an extra measure of viral safety.

Treatment of human immunodeficiency virus-infected lymphocytes with cationized human immunoglobulins

Hyperimmune immunoglobulins from human immunodeficiency virus (HIV)-infected persons may inhibit intracellular viral replication if the HIV immunoglobulins (HIVIG) are delivered to intracellular spaces where the virus replicates. This study examines the hypothesis that cationized forms of HIVIG undergo enhanced absorptive-mediated endocytosis into cells and inhibit HIV replication. HIVIG and nonimmune human intravenous immunoglobulin (IVIG) were cationized with hexamethylenediamine to an isoelectric point (pI) > 9.5. Cationization markedly increased the binding and endocytosis of HIVIG and IVIG by human peripheral blood lymphocytes (PBL). Cationized HIVIG and IVIG (250 micrograms/mL) resulted in a 90% inhibition in p24 released to the medium in HIV-1-infected human PBL. The study demonstrates that cationization of human immunoglobulin preparations, such as HIVIG and IVIG, markedly increases the endocytosis of immunoglobulin and the inhibition of HIV-1 replication in human PBL.

Side-effects of intravenous immune globulins

Intravenous immune globulin (IVIG) preparations are efficacious and safe products in use world-wide. Although rare, side-effects of IVIG may be serious, even life-threatening, and clinicians should be aware of their potential occurrence. This article summarizes most of the adverse experiences with IVIG reported in the literature since its introduction into clinical practice almost 15 years ago.

Pathogenic anti-DNA idiotype-reactive IgG in intravenous immunoglobulin preparations

This study was addressed to explore the reactivity of natural anti-idiotypes from commercial lots of immunoglobulins to several idiotypes (Ids), usually expressed by anti-DNA molecules in lupus nephritis. Eleven intravenous immunoglobulin (IVIG) preparations and nine (three polyvalent and six hyper-immune) intramuscular IgG were investigated for specific content of anti-DNA, anti-F(ab')2 and antibodies reacting with several anti-DNA IgG Ids. Two samples (nos 6 and 11) showed high reactivity with allogeneic F(ab')2 and with F(ab')2 of myeloma proteins bearing the anti-DNA Id 3I+ and the 8.12+. Since both 3I and 8.12 Id markers are known to characterize pathogenic anti-DNA IgG in systemic lupus erythematosus (SLE), anti-Id antibodies to these markers were obtained by absorbing the IVIG samples nos 6 and 11 to Sepharose columns coupled with pooled F(ab')2 fragments of 3I(+)-F4(+)-8.12(+)-myeloma proteins. Inhibition experiments showed that anti-8.12 Id-eluted IgG induced a selective suppression of the DNA-reactive antibodies derived from patients with active lupus nephritis to their substrate, suggesting the involvement of 8.12+ molecules in the SLE glomerular damage. Since 8.12+ anti-DNA are nephritogenic antibodies, the occurrence of anti-8.12+ Id in commercial IVIG may be of potential therapeutic relevance in modulating the pathogenic SLE Id network. Previous variable results of IVIG treatment in SLE, such as resolution of proteinuria or worsening nephritis, could be related to variable enrichment of different lots of IVIG in suppressive anti-pathogenic Id antibodies.