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To obtain diagnostic antibodies to neomycin, immunogenic properties of the neomycin conjugates with macromolecular carriers were studied. Bovine serum albumin and copolymers of N-vinylpyrrolidone with crotonic acid and N-hydroxyphthalimide ether of crotonic acid were used as carriers. It was shown that immunization of mice by the conjugates in combination with Freund's adjuvant resulted in production of neomycin antibodies, the titer being 1/80 to 1/130. When the antibiotic conjugates with the copolymers of N-vinylpyrrolidone were used and not the neomycin conjugates with the carrier of the protein nature, the neomycin antibodies were produced in the absence of Freund's full adjuvant. With the use of the isolated antibodies to neomycin a method for indirect solid phase enzyme immunoassay of neomycin was developed at the minimum detectable level of 25 ng/ml.

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Certain catalytic and immunological properties of L-asparaginase modified by polyglucin were studied. It was shown that the modified forms of L-asparaginase maintained high catalytic activity (Km 0.80.10(-5)-1.89.10(-5) M) and at the same time appeared to be more resistant to inactivation under the effect of antibodies.

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An amperometric transducer with tubular coal electrodes has been worked out to determine the microquantity of peroxidase. The hydrodynamic parameters of the transducer were studied as were the relationship of the output signal to the concentration of the electroactive substance, the length of the electrode, the speed of the background electrolyte movement and the diffusion coefficient. The line section of the relationship between the strength of current and the peroxidase concentration is observed within the interval of the enzymic concentration 1-32 ng/ml with the exposure time of the enzymic reaction of 5-10 min.

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A technique for quantitative determining horseradish peroxidase was developed using an amperometric sensor that makes it possible to register up to 50 pM of the enzyme in the reaction of the peroxidase oxidation of iodide ions by hydrogen peroxide. The sensor, composed of combined carbon and Ag/AgCl electrodes, is intended for enzyme immunoassay and may be used for registering the results in the very wells of the polystyrene plates widely used in clinics and laboratories. The dependences of the initial rate of the enzymatic reaction on the substrate concentration and pH of the medium were determined, on the basis of which the conditions for the optimal operation of the sensor were found. The amperometric and spectrophotometric methods of registration on a model system for determining antibodies against X-virus of potato were compared in order to show a possibility of the sensor applying to enzyme immunoassay.

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Preparations of pancreatic RNAase modified by dextrane derivatives were obtained in an azocombination reaction. The UV absorption spectra and amino acid analysis of the preparations revealed quantitative and qualitative differences in the sites of the enzyme binding to the polymeric matrix depending on modification conditions. The observed differences in the binding sites of modified RNAase may be related both to the differences in the primary structure or even in the secondary and ternary structure of the enzyme. The latter observation was confirmed in studies of the antigenic properties of modified preparations. The interrelationship of these preparations with antibodies raised against native RNAase and the comparison of the degree of their antigenicity suggest the influence of modification on the antigenic properties of the protein. The number of binding sites of the enzyme to the support can be determined, which would neutralize the antigen-stimulated effect of the support due to the screening of protein antigenic determinants.

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T lymphocytes of guinea-pigs were found to form spontaneous E-rosettes with rabbit red blood cells. The lymphocyte count constituted 32% of blood lymphocytes, 41% of lymph node cells. Meanwhile no T lymphocytes were detected in the bone marrow. The T lymphocyte subpopulation capable of forming "early" rosettes was demonstrated. B lymphocytes formed EAC-rosettes with sheep red blood cells. The B lymphocyte count in the blood, lymph nodes and bone marrow amounted to 10, 18 and 5%, respectively. The effects of incubation conditions, centrifugation, antibody types, and complement concentration, etc. on E- and EAC-rosette formation were defined.

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Repeated intravenous injection of total histone of calf thymus preparation led to sensitization of experimental animals accompanied by formation of complement fixing antibodies. Sera examination by the complement fixation test demonstrated antigenicity of the total histone preparation protein components to decrease in the following order: nonhistone proteins admixture greater than histone fraction HI greater than mixture of histone fractions H3 : H2b : H2a (1 : 1 : 1). The presence in the total histone preparation of nonhistone protein admixture chiefly conditioned the immunogenic, and possibly, the allergenic activity of the preparation.

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An immune response to urate oxidase--an enzyme from pig liver was studied. Peculiarities of antibody formation were investigated in three animal species. It was shown that the scheme for repeated injections of the enzyme preparation had a marked effect on the intensity of humoral immune response. In studying the process of the enzyme allergic properties it was found that urate oxidase had anaphylactogenic and skin sensitizing properties. The strength of anaphylactic reaction depened on the sensitizing dose of the antigen and correlated with the results of active skin anaphylaxis. However, there was no correlation between the strength of the immune response determined by means of the indirect hemagglutination test and the intensity of anaphylactic reaction.

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Levorin and mycoheptin, polyenic antibiotics were separated into 3 and 7 heptaenic components respectively by the method of disc electrophoresis in 7.5 per cent polyacryl amide gel prepared with tris-HCl buffer, pH 8.9. It was shown that nystatin had different composition as dependent on the organism producing it. The results of electrophoresis confirmed the data of the counter-current distribution.

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The composition of extracellular proteinases from Actinomyces fradiae 0072 and their effect on proteins and synthetic substrates were studied. The enzyme preparation was found to have keratinolytic, caseinolytic, collagenolytic, collagenase, trypsin-like, carboxy- and aminopeptidase activities. Five low molecular weight proteinases capable to hydrolyse keratin, casein, azocollagen were obtained via fractionation of the enzyme preparation on DEAE-cellulose and Sephadex columns. Proteinases from Act. fradiae and aminopeptidase with a molecular weight of 31,000 were shown to be different enzymes. In hydrolysis of L-leucyl-2-naphthylamide the Michaelis constant and Vmax of the enzyme were found to be 3.02 X 10(-3) M and 0.35 X 10(2) micronM/ml-min, respectively.

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The synthesis of antibodies to proteinases, such as terrilytin, hygrolytin, brinase, trypsin, chemotrypsin and papain was studied by using the complement fixation test and immunoelectrophoresis. The results obtained indicated that proteinases possessing fibrinolytic activities proved to differ considerably by their immunogenic properties. The antibody formation to microbial proteinases was found to be more intensive than against the enzymes from the antimal tissues.

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