Preparation and use of synthetic blood group specific immunoadsorbents.

The carbohydrate structures determining the ABO blood group system have been almost completely characterized. Recent advances in the stereoselective synthesis of such complex structures have made it possible to prepare pure oligosaccharides in large quantities and to study their possible uses for diagnostics and pharmaceutical processing techniques. In the experiments described here A and B blood group specific determinants were synthesized and bound to solid phases by means of suitable spacers in order to study their use as immunoadsorbents. The objective was to adsorb blood group specific antibodies from positive sera and from immunoglobulin preparations. It was shown that the anti-A and anti-B antibodies bound to the immunoadsorbents with high affinity could be removed effectively. The effects were achieved both using affinity chromatography and "batch processing".

Novel effective immunoadsorbents based on agarose-polyaldehyde microsphere beads: synthesis and affinity chromatography.

Agarose-polyaldehyde microsphere beads were produced by encapsulating polyacrolein microspheres or polyglutaraldehyde microspheres with agarose. Magnetic beads were formed by carrying out the encapsulation procedure in the presence of ferrofluidic particles. Proteins were bound covalently, at physiological pH, to the beads through their aldehyde groups to produce the Schiff base products. The conjugates, beads-proteins, were used successfully in affinity chromatography for specific purification of antibodies. Leaching of the proteins bound to the beads under physiological conditions and eluting conditions was not detected. The agarose-polyaldehyde microsphere beads are suggested as alternatives to the supports currently used in affinity chromatography.

Use of F(ab')2 antibody fragments in the synthesis of immunoadsorbents for preparing monospecific antigen.

Class specific F(ab')2 antibody fragments were prepared by pepsin digestion of the labile Fc immunoglobulin fragments in antigen--antibody precipitates. The F(ab')2 fragments were covalently coupled to cyanogen bromide-activated Sepharose 4B and the resultant immunoadsorbent used to isolate IgG from human serum with a single chromatographic step, in high yield and purity and negligible non-specific interaction. This technique affords a simple method for preparing an enriched source of class specific affinity-purified immunoglobulin antibodies suitable for many immunochemical applications.

[Synthesis of a high-capacity immunosorbent based on a cellulose suspension]. / Sintez vysokoemkogo immunosorbenta na osnove suspenzii tselliulozy.

A method is suggested for preparation of an immunosorbent on the basis of cellulose suspension. Antigen was coupled to periodate-oxidized cellulose via aldehyde groups. Optimal conditions (time of oxidation, amount of an oxidant, quantity of protein antigen added) for immunosorbent synthesis were determined. The amount of antibodies bound to the immunosorbent was approximately equal to the weight of the immunosorbent (up to 950 mg of antibodies per 1 g sorbent). Thus each molecule of antigen coupled to cellulose bound 5-8 molecules of antibodies.

Insoluble human plasma protein immunoadsorbents. Large-scale production and storage.

Methods for producing and preserving large volumes of insoluble immunoadsorbents (for removing unwated antibodies to serum proteins) from surplus blood bank plasma by glutaraldehyde were evaluated by quantitative and qualitative means using radioactive 125I and immunoelectrophoresis, respectively. Some of the factors affecting the desired physical characteristics and antibody-absorbing properties of the imjunoadsorbent studied were: plasma acidification, varying concentrations of glutaraldehyde, addition of small amounts of formalin, storage under varying conditions of temperature, and exposure to preservatives in the wet and lyophilized state for periods up to 2.5 years. The best preservation of antibody-adsorbing properties (under storage conditions) was obtained in the washed state at 4 degrees C, but good preservation was also obtained at room temperature in the presence 10% formalin and in the unwashed state at room temperature in the presence of unreacted glutaraldehyde. Lyophilization destroyed about 70% of an adsorbent's activity.