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Biomedical subjects

I M Liampert

Publications and source records attributed to I M Liampert.

At least 55 records · Page 3Linked to original sources
PubMed1980

[Distribution of a cross-reacting antigen common to group A streptococcal polysaccharide and multilayer squamous epithelium in different human organs].

Indirect immunofluorescence with the use of antibodies) to group A streptococcal polysaccharide (A-polysaccharide has shown cross-reacting antigen (CRA) common for A-polysaccharide and the squamous epithelium to be localized, apart from the skin and thymus, in basal layer cells of oral mucosa epithelium, esophagus, inferior portion of the rectum, in salivary and mammary ducts. These tissue carriers of CRA are united by common ectodermal origin. The evidence obtained may be of use in the devising of a method for differential diagnosis of tumors of different genesis. In the course of organogenesis CRA appears early in the monolayer embryonic epithelium. The data presented correlate with those obtained before during study of animal tissues.

Adolescent↗
PubMed1980

[Heart valve fibroblast Fc receptor study and the search for similar receptors in other tissues].

The data are confirmed about the presence of Fc-receptors reacting with human and rabbit IgG on the fibroblasts of human and bovine heart valves. It is shown the similar receptors are present on the fibroblasts of joints and L-cells. The receptors react largely with monomeric IgG. Clear-cut distinctions are revealed between the fibroblasts of heart valves and those of the myocardium which like other cells of myocardial interstitial connective tissue do not contain Fc-receptors.

Animals↗
PubMed1979

[Immunoglobulin receptors of group A Streptococcus].

It was shown in the gel precipitation tests that absorption of human and rabbit IgG or Fc-fragments obtained from human IgG group A streptococcal cultures results in inhibition of the reactions of these preparations with immunoglobulin sera. The reactions of F(ab')2-fragments with the corresponding sera are not inhibited during their absorption by the same cultures. The results obtained support the presence in a number of group A streptococcal cultures of immunoglobulin receptors (Ig-receptors) capable of reacting with Fc-parts of human and rabbit IgG. Pepsin treatment destroys Ig-receptors. These receptors could not be found by the method used in hydrochloric acid extracts prepared from streptococci containing the receptors. The method can be applied for determination of Ig-receptors in streptococcal cultures.

Animals↗
PubMed1979

[Immunological cross reactions between polysaccharides of Streptococci groups A and L].

Antibodies on sepharose immunosorbents containing A-polysaccharide-sepharose or synthetic beta-N-acetylglucosamine, were isolated from the sera of rabbits immunized with streptococci, group A, by means of affinity chromatography. Antibodies obtained from some sera with both immunosorbents reacted with streptococcus, group A and L polysaccharides. Partial identity of these polysaccharides was revealed by the immunodiffusion test. Absorption of antibodies with polysaccharides, group A and L, showed their different specificities. These antibodies could apparently be directed against the end parts of molecules of streptococcus, group A polysaccharide.

Animals↗
PubMed1979

[Immunodiffusion methods of studying the F-fraction antigens obtained from group A streptococci].

F fractions, obtained by the extraction of cultures of group A streptococci with distilled water at different pH, were studied by immunodifusion methods and subjected to chemical analysis. F fractions were shown to contain polyglcerophosphate, antigen E4 and in some cases group polysaccharide. Besides, F fractions were found to contain an antigen insensitive to trypsin and identical to one of the antigens of the thermostable fraction, as well as an antigen sensitive to the action of proteolytic enzymes and common to various types of group A streptococci. The antigen sensitive to the action of proteolytic enzymes were identical to one of the antigens showing no type specificity and contained in HC1 extracts prepared from group A streptococci. In grouping and typing group A streptococci the present of some F fraction antigens unrelated either to polysaccharide or to M substance should be taken into consideration. The antigens of F fraction have no protective properties.

Animals↗
PubMed1977

[Permeability of cutaneous macrophage lysosomal membrane in delayed hypersensitivity to streptococcal antigens].

The acid phosphatase (APh) was studied in the skin macrophage lysosomes of animals with delayed-type hypersensitivity (DTH) to the antigens of group A streptococci or tuberculoproteins. The histochemical procedure for the APh determination was employed in the skin sections without any preliminary tissue fixation. Intradermal injection of specific antigens in DTH proved to lead to the increase of the lysosomal membrane permeability in the skin macrophages. These data support the supposition that the lysosome enzymes of macrophages can act as factors causing tissue destruction in DTH.

Acid Phosphatase↗
PubMed1977

[Reactions of antibodies to streptococcus group A antigens with fibroblasts of human heart interstitial connective tissue].

The indirect immunofluorescence method was applied to the study of the serum of rabbits immunized with fractions containing nontype-specific antigens of streptococcus, group A, belonging to the cell wall proteins. Antibodies reacting with fibroblasts of the interstitial connective tissue of the human heart were revealed in the sera. On the basis of the experimental results of absorption a supposition was put forward on the presence of a cross-reacting antigen common with the fibroblast antigen in some hydrochloric extracts obtained from streptococci, groups A and C.

Animals↗
PubMed1977

[Relationship between the virulence of a culture and the presence of common (non-type-specific) antigens in strains of group A streptococcus of different types].

In studying common (nontypespecific) antigens sensitivity to trypsin there was shown their wide distribution among the cultures of streptococcus, group A, belonging to different types and containing M-proteins. The antigen No. 1, identical to one of the antigens of the thermostable fraction was found in the cultures, irrespective of the degree of their virulence. The antigen No. 2 was characteristic of only virulent cultures obtained after the increase of the virulence and forming matt-form colonies. Both of the antigens were referred to the category of R-antigens. The presence of the nonspecific antigens in the hydrochloric extracts should be taken into consideration in typing streptococci of group A and determination of M-antigens.

Antigens, Bacterial↗
PubMed1976

[Cytotoxic action of immune lymphocytes on "adherent" cells (macrophages) of autologous system lymph nodes during delayed hypersensitivity].

A study was made in the autologous system of the cytotoxic action of immune lymphocytes on the "adherent" cells (macrophages) of the lymph nodes of guinea pigs in delayed hypersensitivity (DH) to the streptococcus antigens and tuberculoproteins. Death of a considerable number of the "adherent" cells in cultivation of a suspension of cells of the lymph nodes of animals sensitized with the culture of streptococcus or BCG in the presence of specific antigen (thermo-stable streptococcus fraction or tuberculin, respectively) alone. Detection of death of the "adherent" cells in the autologous system can be used as one of specific and sensitive tests in studying the DH.

Animals↗
PubMed1976

[Autoantibodies to the common antigenic determinant of group A streptococcal polysaccharide and epithelial cells of mammalian thymus and skin].

A cross-reactive (CR) antigenic determinant in the polysaccharide of group A streptococus and the mammalian thymus and skin was studied. The CR antigen was found in adult humans and human embryos irrespective of the blood group, as well as in the tissues of all the animal species studied, including rabbits immunized with streptococcus and producing antibodies to A polysaccharide. Evidence was obtained that the antibodies elaborated to the CR determinant of polysaccharide A and of the tissue epithelium should be classed as autoantibodies. It is suggested that reaction of these antobodies with the CR antigen in the thymus could serve as one of the causes of autoimmune thymitis during rheumatic fever.

Adult↗
PubMed1976

[Distribution of a cross-reacting antigen common to epithelium and group A streptococci in human and animal tissues].

With the aid of pure antibodies to polysaccharide of streptococcus, of group A, there was revealed by the method of indirect immunofluorescence with the use of pure antibodies to rabbit immunoglobulins (labeled with fluoresceine isothiocianate) localization of the cross-reacting antigen common for streptococcus and tissues of man and animals in the cells of surface epithelium of the ectodermal origin (the skin, salivary ducts, oral mucosa, esophagus, inferior portion of the rectum, uterine cervix, and the elements of the thymus epithelium). Detection of the cross-reacting antigen was of interest in connection with the study of the mechanisms of development of chronic pathological processes in man associated with streptococcus infection and investigation of the structure, function and pathology of the thymus.

Animals↗