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The protein content of identical samples from 5 different cell types (lymphocytes of the thymus and of the bursa of FABRICIUS of the chicken, EHRLICH ascites tumor cells, YOSHIDA ascites tumor cells, and rat liver cells) have been determined both macroscopically, by the method of LOWRY (1951), and microspectrometrically, by the tetrazonium coupling method of NOHAMMER (1978). In all the different cell types, a strong correlation is shown between the protein values determined by the 2 methods. By comparing the values thus measured, a conversion factor has been obtained such that an extinction of 0.4235, determined microspectrometrically, corresponds to a protein mass of 1 pgm. To test the accuracy of the microspectrometric method of protein determination at the lowest extreme point, the protein content of rat liver mitochondria has been measured and a mean value of 0.239 pgm protein per mitochondrion obtained. This corresponds well with the value of 0.233 pgm per mitochondrion as determined macroscopically by GEAR (1972).

The changes in plasma lipoprotein-a Lp-a concentrations during pregnancy were investigated. Out of 42 women with normal pregnancy, 22 reached Lp-a values greater than 10 mg/dL. Plasma levels of Lp-a in addition to total cholesterol, and apolipoprotein B were measured at 4 to 6-week intervals during pregnancy and post partum. The hormones hCG, human placenta lactogen, progesterone, estradiol, and insulin were measured concomitantly. The results can be summarized as follows: Plasma Lp-a concentrations rose steadily during the first trimester of pregnancy and reached a maximum in the middle of the second trimester. Maximal Lp-a values in the 19th week on average were 2.8 times higher as compared to the values of the eight week of pregnancy. Plasma Lp-a fell from the 19th week of pregnancy, reaching a basal value at the time of birth. This value remained virtually unchanged until 6 months post partum. Despite the fact that apolipoprotein-B and total cholesterol rose significantly, exhibiting pronounced maxima during the course of pregnancy, there was no overlap in the shape of their concentration curve with Lp-a. The rise in plasma Lp-a concentration did not correlate with any of the measured hormones at a given time interval. Time shifted analysis of the concentration curve revealed a correlation with hCG, however, with a lag phase of approximately 11 weeks. This study substantiates the independent metabolic control of Lp-a, as compared to plasma apolipoprotein-B and total cholesterol.

In a comprehensive study the concentrations of plasma lipids and lipo- and apolipoproteins were measured in 24 nonpregnant women (control) and longitudinally in 42 women throughout gestation and postpartum. The results were correlated with hCG, 17 beta-estradiol (E2), progesterone (PG), human placental lactogen (hPL), and insulin levels by time series analysis. Insulin concentrations were constant until week 25 and increased thereafter. Plasma E2, PG, and hPL as well as plasma lipid levels rose continuously during gestation. Apolipoproteins AI, AII, and B concentrations increased until weeks 25, 28, and 32, respectively, and remained constant until term. Low density lipoprotein cholesterol reached maximum levels at week 36. High density lipoprotein cholesterol exhibited a triphasic behavior, with maximum levels at week 25, a fall until week 32, and maintenance of the level until term. Time series analysis revealed positive correlations with E2, PG, and hPL. These results provide evidence that apoprotein concentrations undergo pronounced serial changes during gestation, which in part might be due to the effect of E2. Furthermore, the importance of hPL as a determinant of the plasma levels of total and free cholesterol, triglycerides, and phospholipids is now documented.

210 patients harbouring an intracranial tumour were tested for CEA plasma levels. It could be shown that this investigation was neither a useful screening test for detecting brain neoplasms nor suitable for follow-up on operated brain tumours. However, with the CEA plasma investigation an additional preoperative test is available for distinguishing between primary and secondary brain tumours. The positive evidence is only 29%, but in case of a CEA plasma value above 5.0 ng/ml a metastasis is indicated with a probability of 91%.

Assuming a reversible equilibrium of an unfolded and a base-stacked conformation of both NADH and NAD+ the influence of pH, temperature and methanol on this equilibrium was studied as indicated by the UV-absorption of the adenine, band at 260 nm. By the addition of methanol as well as by an increase of temperature the equilibrium is shifted to the unfolded conformation. An increase of the H+ concentration seems to favor the unfolded conformation in the case of NAD+ while for NADH a decrease of the absorption coefficient is pointing to a higher percentage of the stacked conformation at lower pH. From the temperature variation of the absorption coefficients the enthalpies for the conformational change were calculated and compared with data obtained by different methods.

The expression of histocompatibility leukocyte antigen (HLA) class I and class II antigens on human oocytes was investigated by the indirect immunofluorescence assay using well-defined monoclonal antibodies. Oocytes were obtained from an in vitro fertilization program or were studied on frozen sections from human ovaries. Neither HLA class I, beta 2-microglobulin, nor HLA class II molecules were detected on cultured oocytes or frozen sections. The zona pellucida also lacked these antigens, but granulosa cells expressed HLA class I molecules. Our results also indicate the presence of certain types of class II molecules on granulosa cells. The present experiments demonstrate that the human oocyte belongs to those few cell types in the human body which are devoid of both types of HLA molecules.

In aqueous solution Amido Black B (ASB) forms stable and well-defined complexes with bovine serum albumin (RSA) at pH 5.5. The complexes can be separated by column chromatography. The formation of the complexes consist in a fast reaction during which, after 3 to 5 h approximately, 3 molecules of ASB have been bound per molecule RSA, and of a much slower reaction which, even after a laps of 24 h, is still far from approaching its final stage. With solid films of RSA, after denaturation with ethanol, fast reaction is found to approach its final stage after 10 min reaction time. With these model protein preparations, the molar extinction coefficient of the ASB-protein complexes can be determined: the soluble ASB-RSA complexes can be brought to complete dissociation at pH 12.3. After the additivity of the specific absorptions of both RSA and ASB had been proven, it was possible to determine the content of the solution of ASB and RSA, and therefrom the molar extinction coefficient of the ASB-RSA-complex at Ph 5.5: epsilon 620 = 110,000. ASB-stained ethanol-fixed RSA films show an epsilon 620 of approximately 96,000, if their thickness and specific weight are known. After incubation in watery or ethanolic/TCA solutions of ASB, also animal cells fixed with ether-ethanol show the ASB absorption band to be in the region of 600 nm after removal of the surplus of ASB by thorough washings. As already observed with the RSA films, the kinetics of the staining of the cells show the fast reaction reaching its final stage already after 15 to 20 min. When alcoholic solution of ASB is used, the extinctions are found to be twice or three times higher than those achieved by an aqueous one. After standardization of the staining procedures with both solvents the total extinctions of EATZ, YATZ, rat hepatocytes, chicken thymus and bursa cells were measured and plotted against the macroscopically determined protein content of the respective cells. Highly significant positive linear correlations resulted with staining both in watery and alcoholic solutions, respectively. From the slope of the straight lines, specific extinction coefficient of ASB stained cellular proteins could be calculated up to epsilon' 620 = 1.76 with watery ASB solution and epsilon' 620 = 3.83 with the alcoholic solvent. The soluble ASB-RSA complexes have an epsilon' 620 = 1.67 the ASB stained ethanol denaturated films of RSA an epsilon' 620 of within a range of 1.21 to 1.80.

The near-ultraviolet region of the total fluorescence (excitation-emission matrix) of human serum reflects essentially the fluorescence of protein-bound tryptophan. We examined topographically the tryptophan fluorescence of human serum. In comparison with fluorescence topograms from sera of healthy donors, sera of patients with gynecological malignancies showed significantly different patterns of tryptophan fluorescence, the major deviations being at 325 and 365 nm. In healthy donors, the tryptophan fluorescence intensity at 365 nm, expressed as percent of the maximum fluorescence intensity (i.e., at 337 nm) varied little, but was markedly lower for sera from patients with malignancies. We found no clear correlation between the extent of the fluorescence deviations and the relative concentration of the protein fractions as determined by electrophoresis. Furthermore, we could rule out inflammation in tumor patients as an explanation for this effect.

Three possibilities are discussed for the immunological mechanisms which may be operative in establishing and maintaining a successful grafting of a semiallogenic embryo: (1) The lack of maternal allogenic recognition due to either the absence or a decreased alloantigenicity of paternal alloantigens (HLA). (2) The local suppression of maternal immune reactions against the embryo by hormonally induced decidual suppressor cells and by molecules released from the placenta. (3) The placenta may serve as an immunological barrier filtering potentially cytotoxic cells and molecules out of the maternal circulation before they reach the fetus.

The expression of HLA Ag on polyploid early human embryonic stages, obtained in an in vitro fertilization and embryo transfer program, was investigated by indirect immunofluorescence tests using a panel of mAb. Neither HLA class I Ag, beta 2-microglobulin, nor HLA class II molecules could be detected on blastomers. The zona pellucida also lacked these Ag, but granulosa cells expressed HLA class I Ag, beta 2-microglobulin, and HLA class II Ag. These results make it likely that the absence of HLA Ag is one of the mechanisms involved in protecting the implanting embryo from rejection by the immunocompetent mother.

45 infants and children with thrombocytopenia and septicemia were studied. Many parameters of blood coagulation, the platelet diameters and the megakaryocytes of the bone marrow (Feulgen stained cytophotometry and maturity of the megakaryocytes) were examined. 15 patients had a consumption coagulopathy and 30 were classified as having an isolated septic thrombocytopenia. In both groups the number of the megakaryocytes of the bone marrow smears were normal. 81% of the megakaryocytes were mature. The patient group with isolated septic thrombocytopenia had significantly greater ploidy values of the megakaryocytes than a control group. In both groups the diameters of the platelets were also significantly greater than in an age matched control group of children with a normal platelet count. These results allow the conclusion that the thrombocytopenia in pediatric patients with septicemia is not caused by a diminished production of platelets.

The usefulness of protein films denaturated and fixed with ethanol/ether as cytochemical model systems was investigated. Kinetics of staining with amido black 10B were analyzed as well as the spectroscopic properties of the protein-dye complex. The absorption coefficient of the complex was estimated. Data obtained so far are compared with both stained cells and the protein-dye complex in solution. Discussion focuses on the influence of fixation and the possibilities to use the films as systems for calibrating cytochemical stainings.