Possibility of decreasing the anticomplement activity of human immunoglobulin preparations via chemical modification

The physicochemical and immunological properties of the experimental batches of the preparations of placental immunoglobulin, obtained by some methods of chemical modification of the molecule of IgG, have been studied. The possibility of abolishing the anticomplement properties of the preparations treated with sulfitolytic agents manufactured in the USSR has been shown. The optimum conditions permitting the production of the preparation with faintly pronounced anticomplement properties and the full monomer structure of its molecule have been established.     

Effect of human immunoglobulins on mouse intestinal microflora in dysbacteriosis

Human immunoglobulins, injected into mice subcutaneously after their irradiation or at the beginning of antibiotic therapy, protected the mucous membrane of the proximal section of the small intestine from the penetration of enterobacteria. The formation of the protective barrier was observed when immunoglobulin preparations with the titer of antibodies to Escherichia coli O14 between 1:16 and 1:256 was used. The preliminary exhaustion of immunoglobulin preparations with E. coli strain O14 led to the complete loss of their protective properties.     

Principles of constructing efficient erythrocyte immunoglobulin diagnostics

Selection of the method of loading erythrocytes with preparations of immunoglobulins (IG) should be determined by the properties of the sensitins to be used. For the production of efficient antibody diagnostics it is advisable to use amidol while in the case of highly active and concentrated sera, amidol, CrCl3 and glutaraldehyde should be employed. The application of IgG preparations considerably enhances the sensitivity of PHAR in the indication of antigens. Immunoglobulin diagnostics on the basis of IG preparations of normal sera should be produced by means of rivanol, tannin or previously heated erythrocytes. In the multiform group of erythrocyte immunoglobulin diagnostics it is necessary to distinguish antibody and non-antibody preparations. Such a classification is justified with respect to differences in the purpose and the optimum methods of production of immunoglobulin diagnostics.     

Gonadotropic activity of the immunoglobulins from placental, abortion and donor blood

Gonadotropic activity of 106 series of immunoglobulin preparations obtained in the USSR and-the People's Republic of Bulgaria was studied. In difference from donor immunoglobulins, all the preparations of placental materials were contaminated with chorionic gonadotropin. Gonadotropin content in the immunoglobulins made of abortion serum was 2--7 times greater than in the preparations from the retoplacental serum and the placental extracts. The mean results of gonadotropin content in the immunoglobulins obtained by biological studies differed from those obtained from the investigations by immunological methods since the mentioned methods apparently characterized different properties of the hormonal molecule.     

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.     

Isolation and properties of poly(A)-mRNA from mouse plasmacytoma MOPC-21

The non-degradable immunoglobulin polyribosomes were isolated from mouse plasmocytoma MORS-21 according to a previously developed immunochemical procedure. The physico-chemical and biological properties of poly (A)-mRNA isolated from individual polyribosomes were studied. The mRNA preparations obtained can be used as a model for studies of current problems of gene engineering.     

Evaluation of prekallikrein activator (PKA) activity in plasma-derived preparations

The study was carried out on 111 series of human immunoglobulin preparations (81 series for intravenous use, 30 series for intramuscular use) produced abroad and in Poland. Kallikrein (KK) and prekallikrein activator (PKA) activities were identified using chromogenic substrate. S-2302 and proteinase inhibitors were tested by double immunodiffusion method. Several biochemical, biological and serological methods were also applied which are valid in the control of intravenous and intramuscular immunoglobulin preparations. It was found that trace amounts of PKA and KK are present in human immunoglobulin preparations for intravenous use such as Bioglobulina and Gamma-Venina (PKA 0.0092-0.0505 mu kat/L, and KK 0,-0.0093 mu kat/L). On the other hand normal human immunoglobulin preparations for intramuscular use had somewhat higher level of KK and PKA and anti-HBs Immunoglobulin preparations (5.50 mu kat/L and 153.91 mu kat/L) and Tetabulina preparations had very high levels of these factors as compared to remaining preparations (4.50 mu kat/L and 316.5 mu kat/L).     

Interaction of antibodies of different immunoglobulin classes with specific O-antigens and Salmonella haptens]

A study was made of the neutralizing properties of antisalmonella antibodies belonging to different immunoglobulin classes in respect to specific O-antigen (Lipopolysaccharide S. anatum) and haptens of salmonellae. In comparison with IgM-antibodies, IgG-antibodies were more stable bound not only with the univalent trisaccharide determinant, but also with the polysaccharide. However, in regard to the lipopolysaccharide complex the neutralizing activity of IgM- and IgG-antibodies was about the same; IgA-antibodies possessed the greatest neutralizing activity with respect to all the antigenic preparations used. The minimal neutralizing dose of the antigen and haptens increased with the reduction of the size of their molecule. A marked heterogeneity of antibodies of each of the immunoglobulin classes by their antigen-neutralizing properties was revealed in individual sera.     

Antibodies against Pseudomonas aeruginosa toxin in preparations of normal human immunoglobulin

Some lots of commercial normal human immunoglobulin have been found to contain antibodies neutralizing the action of P. aeruginosa exotoxin. The content of antibodies in human immunoglobulin preparations correlates to a certain degree with their protective activity determined in the passive protection test in white mice. Certain lots of normal human immunoglobulin have been found to possess protective activity, but contain no specific antitoxins. The clinical testing of these immunoglobulin preparations used for treating patients with Pseudomonas infections has yielded promising results.     

Design of stable immunoglobulin erythrocyte diagnostica. 1. Erythocyte fixation and their sensitization by specific immunoglobulins]

The work presents the results of developing the method of fixation of erythrocyte constituting the cellular base of immunoglobulin erythrocytic diagnostic preparations and the sensitization of erythrocytes with immunoglobulin preparations of various specificity. Based on Ingraham's method, modified method of erythrocyte stabilization has been developed; it consists in the treatment of 50% cell suspension with 4% formaldehyde solution in the presence of 0.5% sucrose (erythrocyte suspension and formaldehyde solution being in the ratio 1 : 2.5). An economic and highly productive technique of sensitizing erythrocytes with immunoglobulin preparations has been developed. The essence of this technique lies in the interaction between 6% suspension of erythrocytes treated with formalin and tannin and the equal volume of sensitin taken in a working dose. The work also presents the method of synthesizing the bifunctional compound fluoro-borate bis-daizonium complex (obtained from benzidine) and discusses the comparative possibilities of the methods of developing immunoglobulin erythrocytic diagnostic preparations by sensitization of tannin-treated erythrocytes and by chemical conjugation.     

Thermodynamic stability and formation of aggregates of human immunoglobulin G characterised by differential scanning calorimetry and dynamic light scattering

The final process step of polyclonal human immunoglobulin G is formulation with agents such as sugars, polyols, amino acid and salts. Often the most stable formulations were empirically identified. Physicochemical methods, such as differential scanning calorimetry and dynamic light scattering, provide a deeper insight on the biophysical properties of such a protein solution. The combination of these methods proved to be sensitive enough to detect fine differences in the properties relevant for the development of stable protein solutions. The influence of additives, such as maltose and glycine in combination with water or low concentrations of salts, on human immunoglobulin preparations was analysed. Differential scanning calorimetry illustrated that 0.2 M glycine had better stabilising effects compared to 10% maltose. Dynamic light scattering and differential scanning calorimetry revealed that solutions preventing aggregation were not optimal in terms of thermodynamic stability. Aggregation was minimised with increasing ionic strength, shown by dynamic light scattering, whereas thermodynamic stability for heat sensitive parts of human immunoglobulin G, analysed with differential scanning calorimetry, was decreased.     

The fractional composition of immunoglobulin preparations studied by gel filtration on different carriers and by high-pressure liquid chromatography]

The fractional composition of immunoglobulin preparations produced by different manufacturing enterprises of this country has been studied by gel chromatography in columns packed with different carriers (Sephadex G-200 and ultragel AcA-34) and by high-performance liquid chromatography (HPLC). This study has revealed the nonstandard character of immunoglobulin preparations produced according to the same technological procedure (modified Cohn's method). The fractionation of immunoglobulins on different carriers with the use of different methods has yielded similar results confirmed by the statistical processing of the data. The results obtained in the study of the fractional composition of immunoglobulin preparations evidence that gel filtration with the use of ultragel and HPLC have greater resolving capacity in comparison with the method of gel filtration on traditionally used Sephadex G-200.     

人巨细胞病毒IgG 抗体标准品研究进展

人巨细胞病毒(CMV)是威胁人类健康的最重要病原之一。高CMV抗体效价的免疫球蛋白G(IgG)制剂,为临床医生在预防和治疗用药上提供了一个有价值的选择。而CMV免疫球蛋白标准品对于制品的CMV抗体效价测定以及高效价血浆的筛选都至关重要。该标准品对于器官移植/输血安全测试,以及临床诊断都是不可或缺。本综述提供了一种人巨细胞病毒IgG标准品制剂方法以及目前研究进展的概述。此外,本文还关注应用于不同领域的不同CMV IgG抗体效价单位。故本文为人巨细胞病毒免疫球蛋白的开发,人巨细胞病毒IgG抗体诊断试剂的标准化,以及为其质量控制提供参考。     

Molecular composition of the fractions of immunoglobulin preparations studied by gel filtration

The method of gel filtration in columns permitted the separation of aggregated fractions into polymers whose content did not exceed 10% and dimers, their content ranging from 3.6% to 22.11%. The preparations were also found to contain fractions of monomers and fragments, Fab-fragments being detected in 10 out of 20 batches under study (4.04-27.36%). The shelf life of all preparations did not exceed 8-12 months. The use of spectrophotometric techniques ensured obtaining the most objective results in the calculation of the percentage of fractions contained in immunoglobulin preparations. The evaluation of the molecular composition of immunoglobulin preparations by the method of gel filtration is conducive to the improvement of their quality.     

Dependence of the specific activity of antitetanus immunoglobulin on the degree of its fragmentation

Antitetanus immunoglobulin preparations with the increasing content of Fab-fragments (15, 30, 53%) have been obtained under specific experimental conditions. Tests for specific activity have revealed an insignificant decrease (13%) in this activity in the preparation containing 15% of Fab-fragments and its sharp drop in the preparations containing 30-50% of Fab-fragments. The specific activity of antitetanus immunoglobulin has been found to be related to the degree of its fragmentation.     

The carbohydrate component of immunoglobulin G peculiar to malignant growth

The total amount of carbohydrates and some carbohydrate components was studied in total preparations of immunoglobulins of blood serum of healthy people and cancer patients as well as in immunoglobulin G subfraction peculiar to cancer and in the fraction isolated from immunoglobulin G of healthy people blood serum corresponding to the place of column elution. An insignificant increase is established in the content of carbohydrates in the protein peculiar to cancer as compared to their amount in immunoglobulin G of blood serum from healthy people (1.93 and 1.46 g per 100 g of protein, respectively). A conclusion is drawn that the content of the studied substances in the protein peculiar to cancer cannot determine the peculiarities of its physicochemical, immunological and biological properties.     

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.     

The improvement of immunobiological preparations against leptospirosis. An experimental study of a new concentrated purified vaccine against icterohemorrhagic leptospirosis for human immunization

The findings of the study of immunological structure of the population in regions endemic for leptospirosis indicate that the immune status of humans makes it impossible to obtain titrated blood sera for the preparation of antileptospirosis immunoglobulin. The data obtained in the study of the immunobiological properties of a new concentrated vaccine against icterohemorrhagic leptospirosis show the possibility of using this vaccine for the immunization of donors with the aim of obtaining blood sera to be used as raw material for the production of immunobiological preparations.     

Determination of human leukocyte interferon by a microfluorimetric immunologic method]

The possibility of quantitative determination of human leucocyte interferon using FITC-labeled antiinterferon antibodies was studied. A highly specific antiinterferon immunoglobulin was obtained as a result of longterm immunization of a donkey with human leucocyte interferon followed by fractionation and immuno-absorbtion of immune plasma. This immunoglobulin was labeled with FITC and used for human leucocyte interferon assay in direct and indirect reactions of fluorescence immunoinhibition. The titres of different human leucocyte interferon preparations in this immunoassay were comparable with the titres of the same preparations detected by interferon inhibition of viral cytopathic effect.     

Production of monoclonal antibodies against nucleocapsid proteins of herpes simplex virus types 1 and 2.

We prepared mouse hybrid cell lines which produced antibodies against herpes simplex virus type 1 and 2 nucleocapsids. Cell lines 1D4 and 3E1, respectively, secreted immunoglobulin G1 herpes simplex virus type 1 and immunoglobulin G1 herpes simplex virus type 2 antibodies which immunoprecipitated proteins designated p40 and p45 from homologous nucleocapsid preparations but precipitated no proteins from heterologous preparations. In contrast, guinea pig antisera prepared against either herpes simplex virus type 1 or 2 p40 precipitated p40 and p45 from both homologous and heterologous preparations. These findings suggest that p40 and p45 possess similar antigenic determinants and that the monoclonal antibodies that were tested reacted preferentially with the homologous determinants.