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I A Tarkhanova

Publications and source records attributed to I A Tarkhanova.

10 recordsLinked to original sources
PubMed1979

[Comparative analysis of the interaction of protein A from Staphylococcus aureus with native, reduced and aggregated IgG].

In a comparative study the affinity of rabbit and human IgG, native, reduced and aggregated by various methods, to protein A obtained from the cell wall of Staphylococcus aureus was determined. For this purpose the method of the passive hemagglutination inhibition test was developed. The affinity to protein A was found to grow considerably after specific or non-specific IgG aggregation and to decrease by 60% after local damage affecting the structure of the IgG molecule waist as a result of the dissolution of the disulfide bond between its heavy chains. The problem of similarity between such effector properties of IgG as its ability to activate the complement system and to combine with protein A is considered, as well as the problem of the pathogenetic role of immune complexes bound with protein A.

Animals↗
PubMed1977

[Virus-neutralizing properties of rabbit anti-influenzal IgG with a lowered complement-binding and cytophilic activity].

Relationship between the virus-neutralizing property and the effector functions of anti-viral IgG antibody was studied by using rabbit IgG against influenza virus, strain A/PR8/34. The single disulfide bond located in the hinge region of the IgG molecule was reduced to change the effector activity of the antiviral antibody. The reduced antibody retained approximately 50% of the initial complement fixing activity, but lost completely its ability to be fixed in heterologous tissue. When tested in the inhibition-hemagglutination test the reduced antiinfluenza IgG retained complete antigen binding activity. The virus-neutralizing activity of the reduced antiinfluenza IgG (tested on chick embryo) did not differ from that of the crude preparation when 100 EID50 were used. When the dose of the virus was increased up to 1000 EID50 the neutralizing activity of the reduced IgG was found to be less than that of the unreduced one. The results obtained are discussed proceeding from the structural organization of the reduced IgG.

Animals↗
PubMed1976

Complement - fixation in the interaction of normal rabbit gamma G' globulin and its Fab' fragment.

Complement consumption induced by Fab' fragments of rabbit IgG, irrespectively of their state of aggregation, requires the presence of homologous rabbit IgG. Up to a certain concentration of Fab' fragment, the amount of complement fixed is a linear function of the Fab' fragment dose, but further raising of the Fab'-fragment concentration does not result in complete complement consumption in the sample. The interaction between Fab' fragment and IgG is not strictly species specific.

Animals↗
PubMed1976

Enhancement of the immune response by a catabolic product of normal rabbit IgG. Effect of F(ab')2-like fragment.

The serum of partially hepatectomized rabbit taken 4 h after operation possessed the proerty of enhancing the immune response to sheep red blood cells (SRBC) in homologous recipients. An exhaustive absorption of the serum with SRBC stromata did not affect its adjuvant-like activity indicating that an active factor augmented the immune response non-specifically. It was shown that the serum of partially hepatectomized rabbits contained a 5-2S IgG fragment antigenically related to peptic F(ab')2 fragment. The i.v. injection of this fragment together with SRBC into rabbits resulted in enhancement of PFC response and haemagglutinin production. Similar enhancing effect was produced by peptic F(ab')2 fragment obtained from rabbit IgG devoid of anti-SRBC antibodies. Sera of partially hepatectomized rabbits did not contain F(ab')2-like fragments and failed to enhance the immune response if the animals were treated with proteinase inhibitor ('Trasylol'), indicating that the fragment was a cetabolic product of IgG. The results are interpreted in terms of regulation of immunoglobulin synthesis by a split product of autologous IgG.

Animals↗
PubMed1976

[Isolation and immunochemical analysis of the breakdown products of gammaG-globulin contained in the serum of partially hepatectomized rabbits].

As demonstrated by immunochemical methods, the serum of partially hepatectomized rabbits contained a Fab-like fragment of IgG. This fragment was isolated by fractionation of the serum on CM-cellulose following affinity chromatography on Sepharose coated with antibodies against rabbit IgG. The sedimentation constant of the Fab-like fragment was 5.2 S; complete antigenic identity to pepsin F (ab')2 fragment was thus demonstrated. No Fab-like fragment was shown in the serum of sham-operated animals, or in the serum of partially hepatectomized rabbits injected with protease inhibitor Trasilol before and after the operation. It was concluded that Fab-like fragment found in the partially hepatectomized rabbits appeared as a result of splitting the autologous IgG with protease(s) from cells of the liver injured during the operation.

Animals↗