[Effect of carbohydrates and polyols on amide content and protein fragmentation in a lactoglobulin preparation].

Certain carbohydrates and polyols are used at various stages of the production of immunobiological preparations as stabilizers of biological activity, particularly in the production of lactoglobulin (against opportunistic pathogens) using membrane ultrafiltration. This study concerns the effect of these substances on changes in the amide content in proteins of this lactoglobulin. Lactoglobulin was incubated in near-physiological (0.9% NaCl, pH 5.5) 10% solutions of glucose, fructose, and sorbitol at 4 and 35 degrees C for 7, 14, and 28 days. A lactoglobulin solution in 0.9% NaCl, pH 5.5, was used as the control. All substances studied suppressed the reduction of the amide group content of asparagine and, in contrast, increased the rate of amide group removal from glutamine residues in proteins of lactoglobulin preparations.

[The evaluation of the reactogenicity and immunogenic activity of a new concentrated inactivated leptospirosis vaccine]. / Otsenka reaktogennosti i immunogennoi aktivnosti novoi kontsentrirovannoi inaktivirovannoi leptospiroznoi vaktsiny.

In the controlled field trial the reactogenicity, safety and antigenic activity of a new concentrated inactivated leptospirosis vaccine after its administration in one and two injections of 0.5 ml were studied in comparison with those of the existing commercial vaccine, introduced in two injections in doses of 2.0 and 2.5 ml. The new experimental vaccine exhibited low reactogenicity and was found to be safe and highly immunogenic when introduced in a single injection of 0.5 ml. As shown in this trial, the immunogenic characteristics of immunization made in a single injection were not inferior than those obtained as the result of immunization made in two injections, yielding high percentage of seroconversions (89.8% to 98.3%) with respect to 4 Leptospira serogroups and leading to the production of the protective titers of corresponding antibodies. The existing commercial vaccine was inferior to the experimental one in antigenic activity (the frequency of seroconversions, antibody titers). The results of the trial make it possible to recommend the experimental concentrated leptospirosis vaccine for use in medical practice in a dose of 0.5 ml introduced in a single injection.

[The immunochemical and biological properties of Leptospira membranes]. / Immunokhimicheskie i biologicheskie svoistva mebran leptospir.

The immunochemical and biological properties of purified membrane fractions obtained from Leptospira interrogans, serovar copenhageni, strain Rat 2, and Leptospira biflexa, strain Patoc 1, were studied. The presence of genus-specific and group-specific antigens in leptospiral membranes was established by the methods of immunodiffusion analysis, the microagglutination (MA) and lysis tests. In animal experiments cell membrane preparations produced no toxic and allergic effects. Leptospiral membranes obtained from strain Rat 2 ensured the protection of golden hamsters infected with Leptospira virulent culture and induced antibody production in high titers, detected with the use of the MA test, the lysis test and the enzyme immunoassay, in rabbits immunized in two injections.

[The improvement of immunobiological preparations against leptospirosis. An experimental study of a new concentrated purified vaccine against icterohemorrhagic leptospirosis for human immunization]. / Sovershenstvovanie immunobiologicheskikh protivoleptospiroznykh preparatov. Eksperimental'noe izuchenie novoi kontsentrirovannoi ochishchennoi vaktsiny protiv ikterogemorragicheskogo leptospiroza dlia immunizatsii liudei.

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.