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Abstract:  The passive transfer of antibodies and vaccination procedures against p185, the erbB2/neu oncoprotein, are approaches being explored for treatment of human breast cancer. We now report the possibility of using the erbB2/neu gene as an immunogen. This study demonstrates that intramuscular or intradermal injections of rat neuNT full-length DNA into mice generate anti-p185 autoantibodies. Anti-p185 polyclonals were also shown to bind the homologous human receptor ErbB2 and to stain specimens of breast adenocarcinoma from both neu-transgenic mice and humans. Further, in vitro assays demonstrated that anti-p185 IgG (probably dependent on CD4+ Th1) were able to inhibit human SKBR3 tumour cell growth and to mediate their lysis by natural killer cells. The continuous presence of circulating neu autoantibodies in mice did not cause any discernible toxic effects on normal tissues expressing low levels of self-antigen, even after 1 year.

Isolated perfused fed rat livers spontaneously liberated glucose and ortho-phosphate to the medium; 24-hr fasted rat livers did not exhibit these phenomena. In perfused fed rat livers, glucagon (2 μg) increased glucose output and promoted ortho-phosphate incorporation. In perfused fed rat livers, insulin (250 or 500 mU) inhibited the spontaneous liberation of glucose and orthophosphate. Comparable doses of insulin significantly reduced the glucagon (2 μg)-induced increase in glucose output from perfused fed rat liver, but did not affect orthophosphate uptake by the organ.

DNA isolated from rat liver by intensive deproteinization with chloroform/isoamyl alcohol and phenol contains low molecular weight peptides in a quantity of about 20 µg/mg DNA.

Low molecular weight peptides from calf thymus cause a strong dose-dependent stabilization of the DNA. The strength of DNA-peptide interaction is pH-dependent and decreases rapidly above pH 6.5. Moreover the complete kinetics of DNA denaturation and renaturation demonstrates that the peptide fraction increases significantly the DNA renaturation mostly at low temperature, showing that the interaction DNA-thymic effector helps the recombination of complementary DNA segments. The DNA stabilization rate by the peptide fraction is comparable to that obtained by means of high concentration of histones or synthetic polycationic peptides. However, the lack of basic amino acids in the peptide structure is not in favor of strong electrostatic interactions and implies a specific binding of peptide to DNA. The possible correlation of the specific thymic peptides-DNA interaction with the stereochemical kinking scheme of DNA is discussed.

The effect of intravenous glucose upon serum inorganic phosphorus was compared to that of glucagon in 35 diabetic patients taken at random.The subjects were classified in two groups according to their serum phosphate fall following glucose. In a group of 19 patients, the phosphate fall after glucose was less than 0.30 mg/100 ml, and in another group of 16 patients, more than 0.30 mg/100 ml similar to that found in non-diabetic individuals. As a working hypothesis, it has been assumed that diabetics with a normal phosphate fall are producing insulin. It was found that the group with a normal phosphate fall after glucose showed a greater fall after glucagon than the group with defective phosphate fall. On the other hand, the group with defective or absent phosphate fall after glucose also showed a very definite fall after glucagon. It would seem then that the latter substance exerts a direct effect upon serum inorganic phosphate, independent of the reactive insulin secretion produced by the glucose load. This effect is possibly related to the activation of phosphorylase which acts in the process of disintegration of glycogen through the introduction of phosphate in the bonds existing between the hexose molecules.

The effect of D-Glucose, D-Galactose, D-Fructose, L-Rhamnose, L-Sorbose, D-Sorbitol, D-Arabinose, L-Arabinose, and D-Xylose on the serum inorganic phosphate in the normal dog has been studied. D-Glucose, L-Sorbose and D-Sorbitol produced a definite decrease, and D-Arabinose a clear cut rise. By statistical comparison with the variation encountered by taking successive blood samples with the same intervals and under the same experimental conditions, it seems that D-Galactose, L-Rhamnose and D-Xylose have some decreasing power. D-Fructose (pyranose) produced an increase at 45′. D-Arabinose showed inhibitory action on the decreasing effect of glucose and insulin. L-Arabinose exhibits some inhibitory action on the effect of glucose and at 15′ after glucose + insulin.