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O K Baranov

Publications and source records attributed to O K Baranov.

At least 19 recordsLinked to original sources

The mink gene for the lambda light immunoglobulin chain: characterization of cDNA and chromosomal localization.

A cDNA library from mink spleen was constructed by use of the phage lambda gt11. The library was screened using polyvalent serum raised against the mink immunoglobulin lambda chain. As a result, several clones expressing mink immunoglobulin lambda light chains were identified. Sequencing of one of the clones with an 803 bp insert was performed. The insert comprised nearly the entire coding region for the mature lambda light immunoglobulin gene with the exception of the leader polypeptide and several amino acids of the FR1 region of the V segment. Compared with the rabbit, mouse and human lambda light immunoglobulin genes, the homology of the cloned sequence was found to be highest relative to the rabbit gene. With the cloned mink cDNA containing the C-region only as a probe, the DNAs from mink-Chinese hamster hybrid clones were studied. The results of segregation analysis of this mink cDNA sequence and mink chromosomes in the mink-Chinese hamster clone panel allowed us to assign the gene for the lambda light immunoglobulin constant polypeptide (IGLC) to mink Chromosome (Chr) 4.

Animals↗

[Cloning and sequencing of immunoglobin lambda-chain cDNA in american mink (Mustela vison].

cDNA library in the lambda gt11 phage was constructed using poly (A+)-mRNA from mink spleen as a template. Immunoscreening of the library allowed the identification of 2 lambda-related clones containing 370 and 803 bp insertion (lambda IGL-1 and lambda IGL-2). Analysis of the primary structure of lambda IGL-2 demonstrated that it contains a large portion of V lambda-segment, J lambda-segment, C lambda-gene and its 3'-untranslated part. The nucleotide sequences known for the immunoglobulin genes were compared to the sequence of the lambda IGL-2 clone. The highest degree of homology was established for the rabbit lambda-genes, this being 63, 94 and 72% for the RF3 region of V lambda-segment, J lambda-segment and C lambda-region, respectively.

Animals↗

[Mink IgG-allotypes and Aleutian disease].

IgG polymorphism (allotypes H3, H4, H6 and H8 of constant region of the gamma-chain) was investigated in healthy and affected with Aleutian disease (AD) minks from two Siberian and one Danish populations. In all three populations, the expression of H3 and H4 allotypes was strongly associated with AD. Among the AD minks the frequency of H6, H8 phenotype was found to be decreased, whereas the frequency of H3, H4, H6, H8 phenotype was significantly increased. At the same time, the populational distribution of the rest phenotypes was similar among healthy and AD minks. The H3, H4, H6, H8 minks showed the highest pathomorphological characteristics of AD. Based on the data concerning mink H3 and H4, and human Gm allotypes, their role as possible genetic markers for hereditary susceptibility to distinct disease is discussed.

Aleutian Mink Disease↗

[The results of international comparative testing of reagents to swine serum protein allotypes conducted in 1987-1988].

Antisera to 15 allotypes of pig serum protein were raised and compared with those prepared elsewhere, within the framework of International Comparison Test of pig blood groups and polymorphic proteins and enzymes in 1987-1988. Of 15 allotypes tested 8 were found to coincide with the known GpB, GpD, GpA, Gpa, IGH3 C1, Lpb3, Lpb12, Lbr1. For 7 allotypes left, no analogues were found out. They seem very likely to be new allotypes of pig serum proteins.

Animals↗

[Genetic variability of antigenic structure of the Lpm-protein and alpha2-macroglobulin among non-mustelid mammals].

The data on interspecific distribution and antigenic variability of homologues of mink Lpm-protein (Lpm) and alpha 2M-globulin (alpha 2M) among 43 species of 6 orders of mammals are presented. Strong variability of antigenic structure of Lpm and alpha 2M of Rodentia and Artiodactyla orders was established. This fact allows to classify the macroglobulins studied as belonging to the group of evolutionary high-speed plasma globulins. In the plasma of human and green marmoset (Cercopithecus aephiops) the only homologue of alpha 2M was found. The lack of reaction to Lpm in above-mentioned species allows to postulate significant differences between Carnivora and Primates in the organization of this gene cluster. Unique features of antigenic variability of Lpm and alpha 2M were also fixed among other systematical groups tested. Taken together, the data obtained stimulate scientific interest to the study of molecular organization of the Lpm and alpha 2M gene families.

Animals↗

Genetic polymorphism of IgG in the mink. V. Two new genetic markers of the lambda light chains of mink immunoglobulins, L4 and L5.

Two new allotypes of the light (L) chains IgG, L4 and L5, were identified in the mink with dispecific antiserum produced by immunization with allogenic IgG. By means of hybrid IgG molecules and proteolytic fragments, L4 and L5 were localized on the C region of the L chain. L4 and L5 occurred frequently in the three mink populations studied and L4 and L5 are inherited independently of the known mink C gamma allotypes. L4 and L5 are encoded by closely linked genes. The antigenic specificities of L4 and L5 were not identified in the closely related Mustelidae and in the other mammalian representatives. Consequently, L4 and L5 are species specific to mink. Determination of the phenotype combinations of the five allotypes on the L chains (including the new L4 and L5) demonstrated the existence of seven combinations only with a predominance of L1,2,3; L4,5, and L1,2,3,4,5 phenotypes. Based on the results obtained, it is concluded that the mink C lambda locus has a complex organization. A model for the mink C lambda locus with at least three or possibly five linked genes is suggested.

Animals↗

[Immunogenetic study of porcine IgG].

Three allotypes of IgG were identified in pig. Based on data obtained on electrophoretic mobility as well as on results of the International Comparative Test ISABR for pig blood group, polymorphic proteins and enzymes (1987-1988), the allotypes are specified as markers of two different IgG subclasses and are referred to as IgG1a, IgG2b and IgG2c. The former of these is established as corresponding to the already known IGH3 C1, and the other two had not been earlier described. In herds of pigs being bred in the Georgian SSR, the IgG1a allotype frequencies in Kakhetinskaya, Large White, Landrase and Lithuanian white were 0.84, 0.93, 0.91 and 0.94, respectively, whereas for the IgG2b allotype it ran 0.89, 0.73, 0.79, and 0.69 in the order mentioned. The IgG2c allotype was not registered in samples under examination.

Alleles↗

Mink-mouse hybridomas that secrete mink immunoglobulin G.

Optimum conditions were established to obtain mink-mouse interspecific hybridomas secreting mink IgG in fusions of mouse myelomas with mink immune spleen cells. Minks were immunized with allogeneic IgG, and the spleen cells were fused with three mouse myeloma lines P3-X63-Ag8.653, NSO and Sp2/0-Ag14. Of these, P3-X63-Ag8.653 and NSO were found to be the best fusion partners giving the highest yield of hybrid clones and number of IgG secreting clones. Cloning of mink-mouse hybridomas was efficient when BALB/c nu/nu peritoneal and spleen cells were used as feeders. The ten clonal lines produced secreted intact mink IgG molecules as shown by SDS-PAGE and subsequent immunoblotting. The secretion level of IgG ranged from 5 to 200 ng/ml in the clonal lines.

Animals↗

[Genetics and evolution of the mink Lpm-system. VIII. Characteristic changes in the antigenic structure of Lpm-protein and alpha2- macroglobulin in Mustelidae family].

Interspecific variability of the isotypic structure of two macroglobulins (Lpm and alpha 2M) in Mustelidae family was investigated using monospecific rabbit antisera against Lpm and alpha 2M Mustela vison. It was established that all the species studied may be divided into four groups, according to the degree of their homology with Lpm: 1) M. vison; 2) M. altaica, M. erminea, Kolonocus sibirica, Putorius eversmany, P. putorius, Luteola lutreola; 3) Vormela peregusna; 4) Martes martes, M. foina, M. zibellina. The greatest divergence of Martes gene species from M. vison and other species studied is determined by two different immunogenetic approaches, the first based on the whole isotype of Lpm and the other using allotypic markers of individual Lpm genes. The variability of the isotypic structure of alpha 2M was lower than that revealed in Lpm. V. peregusna is the only species which significantly differs from all above-mentioned species, including M. vison. The differences established for degree of variability between Lpm and alpha 2M in Mustelidae family may be connected with the evolutionary peculiarities of these two genetic system of serum alpha-macroglobulins, which being phylogenetically related, are still structurally divergent.

Animals↗

Genetic polymorphism of IgG in the mink. III. Instability of expression and the problem of the genetic control of C gamma-allotypes.

Quantitative expression of C gamma-allotype H4 of mink immunoglobulins was studied by enzyme-linked immunosorbent assay. The results presented suggest that production of H4 is under specific regulation. the concentration of H4 varies three orders of magnitude (10-10,000 micrograms/ml) from one mink to another. Fifteen percent of the sera of normal minks have the low H4 concentration, undetectable by the standard procedure of double immunodiffusion routinely used to test mink IgG allotypes. However, expression of these 'minor' allotypes may be significantly enhanced by hyperimmunization. Instability of this kind seems to be the main cause of earlier described deviations from Mendelian inheritance of C gamma-allotypes H2, H3 and H4.

Animals↗

Genetic polymorphism of IgG in the mink. IV. Identification and genetic control of L3 allotype of the light chains.

A new allotype of the mink light chains, designated L3, was identified. This allotype is inherited as a Mendelian character at a frequency of 0.46 in the mink population. Data were obtained indicating that L3 is independent of the C gamma-heavy chain allotypes of mink immunoglobulins. The gene L3 is closely linked to a gene encoding L1, another light chain allotype. Alloantigens L1 and L3 are presumably markers of the light chains of two different subtypes. In contrast to L1, which occurs in many mammalian species, L3 is species-specific, i.e., it is a case of light chain polymorphism representative of the whole mink species.

Animals↗

[Genetics and evolution of the Lpm-system in American mink. VI. Identification, genetic control and phylogenesis of the new allotype Lpm13].

Data on immuno- and biochemical identification, genetic control and phylogenesis of new allotype Lpm13 of the Lpm system in domestic mink are presented. This allotype is encountered in mink populations with the frequency 0.9 and higher. The availability of Lpm13 genetic marker permitted another haplotype to be revealed, in addition to the eight known Lpm haplotypes by means of genetic analysis. It was established that, alongside with the earlier described haplotype Lpm3,4,6,8,9,10,11 (abbreviation H3), there exists a similar haplotype, Lpm3,4,6,8,9,10,11,13 (abbreviation H3.13), containing the Lpm13 gene. Of the rest seven haplotypes, five have the Lpm13 gene and two do not. Taking into account this gene and corresponding antigenic marker, the differentiation of 28, instead of 25, phenotypes and 45, instead of 36, genotypes for the Lpm system became possible. Lpm13 antigenic specificity was found with no exception in all individual serum samples taken from ten species and interspecific hybrids of Mustelidae which are closely related to domestic mink. The data obtained give grounds to refer the newly identified Lpm13 gene to the first evolutionary conservative category of genes of the multigenic Lpm system which is also represented by the Lpm6, Lpm9, Lpm10 and Lpm11 genes. The hypotheses of instantaneous formation of polymorphism of the Lpm system in domestic mink are briefly regarded.

Animals↗

[Immunoglobulin (IgG) allotypes of the American mink with Aleutian disease].

Mink Aleutian disease (AD) is characterized by intensive proliferation of B-lymphocytes and hypergammaglobulinemia. Populational distribution of five genetic immunoglobulin markers (light chain allotype L1 and C gamma-allotypes H2, H3, H6 and H8) in minks of different coat color (Sapphire, Standard and Topaz) was studied. The groups of infected minks differed significantly from healthy ones in the distribution of the H3 allotype: the frequencies of some phenotypes--H3, H6, H8 and L1, H3, H6, H8 (Sapphire, Standard). H2, H3, H6, H8 and L1, H2, H3, H6, H8 (Sapphire) were increased significantly. At the same time, the frequencies of H6, H8; L1, H6, H8 and H2, H6, H8; L1, H2, H6, H8 were decreased in the AD population. The preferential stimulation of proliferation of the H3 + B-lymphocyte clones is suggested.

Aleutian Mink Disease↗

[Immunogenetics of immunoglobulins of the American mink. VI. Deviation from Mendelian segregation for Cgamma-allotypes H2, H3 and H4].

The non-expression of parental allotype among mink F1 offsprings of monohybrid analyzing crosses was established for C gamma-allotypes. A phenotype ratio 0:1, instead of the expected Mendelian 1:1, was observed in some families. The non-expression of allotype may occur in the progeny of mink with normal allotypic specificity. Deviations of allotypic expression had both qualitative and quantitative nature and did not depend on the direction of crossings. Sometimes, the appearance of allotype in a mink could not be expected on the basis of its pedigree. Instability of expression and inheritance of H2, H3 and H4 in many families may have masked the allelic or linkage relationships of these genetic markers.

Animals↗

Genetic polymorphism of IgG in mink. I. Identification of 8 allotypes.

By means of intraspecific immunization of domestic mink (Mustela vison Schr.), 8, in all probability, complex IgG allotypes were detected in their sera. Based on the results of analysis of the preparations of the IgG heavy (H) and light (L) chains, as well as proteolytic IgG fragments, we assigned the allotypes detected to three groups: (1) marker of the L chain, L1; (2) allotypes of the C region of gamma-chains (H2, H3, H4, H6, and H8) and conformational allotype H7; (3) conformational allotype 5 with unknown location on the chains.

Animals↗