[Immunochemical identification and study of an interspecific thymus antigen (AgT-1)]. / Immunokhimicheskaia identifikatsiia i izuchenie mezhvidovogo antigena timusa (AgT-1).

A new interspecific human and animal thymic antigen (AgT-1) was identified immunochemically. It was shown that AgT-1 is a protein with a molecular mass about 40000 dalton, electrophoretic mobility of alpha 1-globulins and isoelectric points 4.0 and 4.5. Heating of the protein to 80 degrees C led to the loss of its immunochemical activity. Antisera to AgT-1 were obtained by immunization of rabbits by conjugated extract of bovine thymus in complete Freund's adjuvant. AgT-1 was identified immunochemically in bovine embryonal thymus, spleen and liver. In addition to these organs, AgT-1 was discovered in lung extracts of adult animals. Identical antigen was identified in the embryonal thymus and extracts of human small intestine. AgT-1 antibodies inhibited the biological activity of the active thymic fraction (AFT-6) in recovering the sensitivity of spleen fRFC from thymectomized mice to the inhibitory action of azathioprin. The data indicate that the biological activity of AFT-6 is partly due to the molecules having antigenic determinants of AgT-1.

[Use of Wheat Germ Lectin-Sepharose for isolating pregnancy-specific protein]. / Ispol'zovanie Wheat Germ Lectin-Sepharose dlia vydeleniia spetsificheskogo belka beremennosti.

Specific pregnancy protein was obtained from retroplacental blood serum by saline fractionation, affinity chromatography on Wheat germ Lectin-Sepharose, gel filtration on Sephadex G-200, hydrophobic chromatography on Phenyl-Sepharose, and ion exchange chromatography on DEAE-Sephacel. The purified preparation of specific pregnancy protein is highly suitable for preparing antisera and the development of immuno- and radioassays of the protein in question.

[Animal analogs of human embryonal prealbumin-2]. / Analogi émbrional'nogo preal'bumina-2 cheloveka u zhivotnykh.

Immunochemical analogs of human embryonal prealbumin-2 (EPA-2) were found in blood sera and amniotic fluid of the cow, sheep and pig fetuses. Meanwhile they were not detected in blood sera of adult animals. Analogs of animal EPA-2 produced the reaction of complete immunochemical identity with human EPA-2. Moreover, they have similar physicochemical properties and electrophoretic mobility of prealbumins. The indirect immunofluorescence technique was used to locate EPA-2 in collagenic fibres of fetuses and in adult animals' connective tissue. It is suggested that EPA-2 might be the protein contained by procollagen or by non-collagenic components of collagenic fibres.

[Immunochemical study of the embryonal prealbumin-2 (EPA-2) in embryonal and adult human tissues]. / Immunokhimicheskoe izuchenie émbrional'nogo preal'bumina-2 (EPA-2) v tkaniakh ploda i vzroslogo cheloveka.

Embryonal prealbumin-2 /EPA-2/ was shown to be a protein, which was actively synthesized in fetus during embryogenesis. The highest content of EPA-2 was found in soft fetal tissues; this suggesting that the protein synthesis occurred in organs of mesodermal origin. To the moment of delivery the content of EPA-2 in fetus was distinctly decreased and the protein was not detected using the immunodiffusion technique in blood serum of adult persons, i e. the EPA-2 synthesis was markedly reduced. Low content of EPA-2 was observed in human gastrointestinal tract, locomotive system, spleen and skin tissues. The EPA-2 synthesis was increased distinctly in malignant tumors, especially, of connective tissue, whereas in tumors of epithelial tissue the content of EPA-2 often depended on presence of connective tissue elements.

[alpha-fetoprotein biosynthesis in a human embryonic tissue culture]. / Izuchenie biosinteza al'fa-fetoproteina v kul'ture tkanei émbriona cheloveka.

Labelled amino acids from 14C-chlorella hydrolysate incorporated into alpha-fetoprotein during "in vitro" cultivation of fetal liver, gastrointestinal tract, lung, kidney and bone tissues, obtained with in 6-12 weeks of pregnancy. alpha-Fetoprotein was apparently synthesized in tissues of entodermal origin.

[Biosynthesis and cellular localization of embryonal prealbumin in human embryonal tissues]. / Izuchenie biosinteza i kletochnoi lokalizatsii embrional'nogo preal'bumina v tkaniakh ploda cheloveka.

Immunofluorescent analysis of chorion sections and various embryonal tissues revealed localization of embryonal prealbumin (EPA) in the mesenchymal cells of the chorion, bones, umbilical cord, skin and in the cytoplasm of the epithelium distal part of the embryonal kidney canals. Synthesis of EPA slow peak in the suspension tissue culture of the chorion, umbilical cord and bones was shown. It is suggested that EPA is a mesenchyme product which is actively synthesized during the period of embryonal development. EPA is resynthesized and localized in the cells of tumors originated from the connective tissue. Cells of the tumors of non-connective origin did not contain EPA, whereas it was detected in the cells of the adjacent connective tissue. The phenomenon of embryonal reversion, probably, takes place not only in the "original" tumor cells but also in the surrounding connective tissues.

[Quantitative immunoenzyme technic in the evaluation of specificity of the beta 1-g-globulin test in trophoblastic tumors]. / Kolichestvennyi immunofermentnyi metod v otsenke spetsifichnosti testa na beta 1-g-globulin pri trofoblasticheskikh opukholiakh.

The method of guantitative immunoenzymatic determination of beta 1-G-globulin (TSG) in the blood serum has been developed. The sensitivity of the method is 6 ng/ml TSG. It has been shown that elevated levels (12-100 ng/ml and higher) are usually observed in trophoblastic tumours of the uterus. The TSG ectopic synthesis is found to proceed in some tumours of the gastrointestinal tract and testicular teratoblastomas.

[Immunochemical study of the specific antigens of human amniotic fluid]. / Immunokhimicheskoe izuchenie spetsificheskikh antigenov amnioticheskoi zhidkosti cheloveka.

Four specific antigens (trophoblastic beta 1-globulin, placental lactogen, alpha 1- and alpha 2-globulins of human placenta) were identified using antisera to the native amniotic fluid. Five antigens with the mobility of prealbumins, alpha 1-globulins, alpha 2-globulins and beta 2-globulins which bear no resemblance with the previously studied antigens were identified using antisera to the acid fraction of the amniotic fluid. Both the prealbumins and alpha 2-globulin were found in the blood serum of foetuses of different age and of newborn infants; these proteins were absent from the blood serum of pregnant women and donors. They received the names of embryonic prealbumine 1, embryonic prealbumine 2 and embryonic alpha 2-globulin. The protein with the mobility of alpha 1-globulins was found in the amniotic fluid of foetuses and in the blood serum of pregnant women only and received the name of amniotic alpha 1-globulin. The concentration of the antigens in question was studied in the developing foetuses and in the blood serum of pregnant women at different stages of pregnancy.

[Biosynthesis and cellular localization of betal-g-globulin in the human placenta]. / Izuchenie biosinteza i kletochnoi lokalizatsii betal-g-globulina v platsente cheloveka

Pregnancy-specific beta1-globulin (beta1-GP) described by Tatarinov and Masyukevich, 1970) was shown by means of immunodiffusion in agar gel to be similar to specific pregnancy beta1-glycoprotein of Bohn (1971) as well as to pregnancy associated plasma protein-C of Lin et al (1974). It was found that in immature placenta (6-12 weeks of pregnancy) incorporation of 14S-amino acids into beta1-GP took place. Studies on immunofluorescence showed that beta1-GP was localized in cytoplasma of trophoblastic cells of placenta chorion. Beta1-GP production apparently begins in Langhans cells and proceeds in syncytiotrophoblastic cells, but at lower activity and secretory scale.

Human pregnancy-specific beta1-globulin and its relation to chorioepithelioma.

Human serum pregnancy-specific beta1-globulin (beta1-GP) was localized in paraffin sections of placenta and chorioepithelioma of the uterus by indirect immunofluorescence. The structures containing beta1-GP but not human serum albumin were regarded as specifically associated with beta1-GP metabolism. Beta1-GP was found in trophoblastic cells of chorion and Langhans cells of chorioepithelioma. Using the immunoautoradiographic method (I131), we only found beta1-GP in sera of patients with trophoblastic tumours: in 74.3% of 35 patients with chorioepithelioma and in 80% of 25 patients with hydatidiform mole and destructive hydatidform mole. The diagnostic and prognostic significance of the immunochemical test for beta1-GP in trophoblastic tumours is discussed.

[Immunoautoradiographic determination of beta-1 gamma globulin in the blood serum of patients with trophoblastic tumors]. / Immunoautoradiograficheskoe opredelenie beta-1 gamma-globulina v syvorotke krovi bol'nykh s trofoblasticheskimi opukholiami

The authors determined beta1-G-globulin (beta1GG) in the sera of patients with different malignant tumours and of normal donors by means of the immunodiffusion method (ID) and immunoautoradiography (IAR). In the ID-negative sera beta1GG was revealed by means of IAR in 7 out of 8 patients with chorionepithelioma of the uterus and in 1 out of 7 patients with teratomblastoma of the testis before the treatment. After the treatment the beta1GG was determined in 7 out of 21 patients with chorionepithelioma of the uterus. At the early stage of trophoblastic tumours of the uterus beta1GG could be found in 77.7% of cases by means of IAR and in 16.8% of cases by means of the ID method.