title: Recombinant N-Domain of Pregnancy-Specific Glycoprotein from E. coli Cells: Analysis of the Spectrum of Polyclonal Antibodies.
abstract: We studied antibody spectrum in antisera to IgG-like recombinant N-domain of pregnancyspecific glycoprotein-1 (rPSG-N) from E. coli cells. In three experimental series, the fraction of IgG antibodies from anti-rPSG-N sera was immobilized on 3 immunoadsorbents: by polymerization with glutaraldehyde, on glutaraldehyde activated biogel P-300, and on commercial CNBr-activated 4B sepharose. Retroplacental serum was incubated with immobilized antibodies to rPSG1-N, protein was eluted and tested in the precipitation test in standard test systems with PSG1, IgG, and human serum albumin. Three proteins were eluted from all 3 immunoadsorbents: PSG1, IgG, and human serum albumin, which demonstrated the spectrum of antibodies to 3 proteins present also in natural serum PSG1 complex. The proportions of PSG1 and IgG obtained in these experiments were similar to those in natural serum PSG1 complex, while the level of human serum albumin was significantly higher in natural PSG1 complex. Thus, we failed to obtain PSG1 monoprotein free from IgG and human serum albumin. Antigenic mosaicism of the polypeptide chain of IgG-like rPSG1-N relative to the antigenic polyvalence of the complex of three proteins present in bioactive preparation of natural serum PSG1 was discussed.
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia. prokopenko_pg@rsmu.ru.
authors.forename: P G
authors.initials: PG
authors.lastname: Prokopenko
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia.
authors.forename: A N
authors.initials: AN
authors.lastname: Shkoporov
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia.
authors.forename: O Yu
authors.initials: OY
authors.lastname: Petrenko
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia.
authors.forename: B A
authors.initials: BA
authors.lastname: Efimov
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia.
authors.forename: V V
authors.initials: VV
authors.lastname: Negrebetskii
authors.affiliation: N. I. Pirogov Russian National Research Medical University, Moscow, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Terent'ev
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D055910:Antibodies, Immobilized / Q000276:immunology; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D006801:Humans; D007106:Immune Sera; D007074:Immunoglobulin G / Q000276:immunology*; D047468:Immunoprecipitation; D011268:Pregnancy-Specific beta 1-Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D017434:Protein Structure, Tertiary; D011817:Rabbits; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000906:Antibodies; D055910:Antibodies, Immobilized; D007106:Immune Sera; D007074:Immunoglobulin G; D011268:Pregnancy-Specific beta 1-Glycoproteins; D011994:Recombinant Proteins
keywords: IgG-like N-domain; antibody spectrum; antigenic mosaicism of polypeptide chain; pregnancy-specific glycoprotein-1 (PSG1); recombinant analog from E. coli cells