Immunoscintigraphy of experimental transplantable tumours using monoclonal antibody against myelin basic protein.

Monoclonal antibody was prepared against myelin basic protein a so-called pancarcinoma antigen. After labelling with 131I the monoclonal antibody was injected into Lewis-lung cancer mice and rats with Walker breast cancer. Two, 24, 48, 72 and 96 hours after the labelled monoclonal antibody injection, radioimmunoimaging studies were carried out. After each gamma-camera study, organ distribution of the labelled monoclonal antibody was determined with radiobioassay technique which showed significantly higher activity in the tumour tissue than in healthy ones. Significant sample radioactivity could be recovered in the tumour masses 48 hours after injection, which persisted even after 96 hours. The later finding might enable diagnosing types of malignancy with isotope-labelled monoclonal antibody against myelin basic protein.

Change of serum HPL level in maternal vein, umbilical cord vein and artery in mature and premature labour.

The authors examined the possible role of HPL in the onset of labour. The HPL level of the maternal vein, the umbilical cord vein and artery was compared in vaginal mature (n = 16) and premature (n = 52) deliveries. The HPL concentration was also examined in mature (n = 18) and premature (n = 18) deliveries performed by caesarean section prior to the onset of labour. The results showed that: the serum HPL level in the maternal vein, the umbilical cord vein and artery was lower during the 33rd-36th and the 40th weeks in cases of vaginal delivery compared to elective caesarean section; The artery/vein ratio decreases during labour (A/V X 100 value), indicating that HPL metabolism in the fetus decreases during regular labour pains; The onset of premature labour and delivery was associated with lower HPL levels compared to normal pregnancy. The authors assume that the lower HPL level found in cases of vaginal delivery may be due to reduced placental perfusion, but they do not exclude the possible association of lower HPL concentrations in cases of premature delivery.

Serum HPL level in maternal vein, umbilical cord artery and vein in term and preterm birth.

The serum HPL level in maternal vein and the cord vein and artery in term (n = 34) and preterm (n = 74) birth was tested to classify the hormonal changes and the correlation between the maternal and fetal HPL values. It was found that between the 28th and the 40th weeks of gestation the maternal level tended to increase while in the cord vein and artery it decreased significantly in negative correlation with the weeks of pregnancy. The maternal serum HPL level was significantly higher than that of the cord vein and artery. Between the 28th and 40th week the value in the cord artery divided by the value in the cord vein multiplied by 100 tended to decrease. While the HPL concentration in maternal serum did not correlate with its level in the cord vein and artery the levels in the cord vein and artery were significantly correlated. The characteristic and independent change in the fetal serum HPL concentration raised the possibility of a change in the transport function of the placenta and of an autonomous fetal HPL metabolism.

Production and properties of antiserum for radioimmunoassay of serum conjugated chenodeoxycholic acid and its preliminary application.

Sensitive tritiated radioimmunoassay was developed for conjugated chenodeoxycholic acid, using immunogen prepared by the mixed anhydride method. The obtained molar bile salt-BSA ratio in the immunogen was 19:1. The distinguishing features of the immunization procedure were a preliminary vaccination of the animal with antitubercular vaccine (VDS), and the administration of very small doses of immunogen (50 micrograms). Assay sensitivity for this bile salt fell in the picomole range with the standard curve extending from 1.5 to 150 pmol. Specificity of the antiserum was compared with that of the commercially available "Glycochenodeoxycholic acid RIA kit" (Nordiclab Oy, Oulu, Finland), and proved to be satisfactory. Fasting serum conjugated chenodeoxycholic acid concentration in 25 healthy subjects and 15 patients with cirrhosis was 0.63 mumol/l and 43.05 mumol/l, respectively. The assay was performed on unextracted sera.

Inhibition of autoimmune hepatitis with hot labelled liver specific antigen.

In accordance with the clonal selection theory the authors intended to prevent the development of autoimmune hepatitis in rabbits with the aid of radiolabelled liver specific membrane (LSP) antigen administered prior to the antigen immunization. The autoimmune hepatitis was produced in rabbits by allogen LSP antigen. The inflammatory reaction was characterized by the serum glutamic oxaloacetic transaminase activity in the sera, by the parameters of immune reaction as well as by lysosomal membrane alterations in the liver and by morphological findings. The process was inhibited by pre-treatment with hot labelled LSP antigen. Neither the radioactively labelled growth hormone pre-treatment, nor the application of hot labelled antigen at the last week of the experiment were able to prevent the humoral and lysosomal, as well as the morphological data characteristic for autoimmune hepatitis. The results obtained may be understood considering the mechanism of clonal selection.

The use of 17-epimethyltestosterone radioimmunoassay in following excretion of methandienone metabolites in urine.

A radioimmunoassay determination method was developed for 17-epimethyltestosterone (17 alpha-hydroxy-17-methyl-4-androstein-3-one). Excretion of metabolites during and after methandienone (17 beta-hydroxy-17-methyl-1,4-androstadien-3-one) administration was followed in human urine samples by RIA tests for methandienone and 17-epimethyltestosterone. While alternating peaks were found in both measured excretion curves, their addition results in a normal curve showing a plateau between the 3rd and 6th day of the drug administration. Furthermore, due to the presence of higher amounts of epi-configurated metabolites, the new test has a higher effectiveness in the detection of the metabolites.

[Prostaglandins in skin blisters of bullous erysipelas, dermatitis herpetiformis and herpes gestationis (author's transl)]. / Prostaglandine in Hautblasen bei Erysipelas bullosum, Dermatitis herpetiformis und Herpes gestationis.

The PGE2 and PGF2 alpha content of bullae developing spontaneously on the skin was investigated by radioimmunoassay in 12 patients with different skin diseases. The PGF2 alpha level was also established in the plasma and urine. In herpes gestationis, dermatitis herpetiformis and bullous erysipelas the PGE2 and PGF2 alpha content of the bullae considerably exceeded the plasma and urinary PG levels. The findings were thought to be in relation with the acute inflammation of the skin, the mechanism of bulla formation as well as with pruritus.

Perspectives in scintigraphic detection of gynecologic tumors using labeled estrogen.

After having succeeded in imaging the prostate with 131I-Estracyt in our former experiments we tried to use the same method for scanning gynecological tumors. In about fifty per cent of the patients (34 cases) there was a convenient accumulation of the labeled estrogen, first of all the adenoid tumors, myomas of uteri and carcinomas can take up this radiopharmacon. Though the number of cases is rather low it is to be concluded that tumors of hormonal dependence can be scanned using estrogen hormon. Further investigations are in progress.

Effect of phytohaemagglutinin on primary immune response in the rat.

PHA pretreatment if given as a single stimulus exerted a stimulatory effect on SRBC haemolysin production rats. If administered repeatedly, it proved to be immunosuppressive.