The basis of our interpretation in terms of an immunizing effect on the newborn, is that in those circumstances where irradiated pure-strain cells present the correct H-2 antigenic stimulus to the host, the pheno- menon shows itself, and in those circumstances where there is either no antigenic difference or there is a non-H-2 difference, we don't get the phenomenon. The Foundation convenes many other informal discussions between research workers of different disciplines and different nationahties and each year invites an outstanding authority to dehver a special lecture. Reproduced by permission of the Editors, Proc. Barrett would confirm, do vary considerably with the strain combination that is used. This particular trial was not very successful, but it does seem to me that the idea merits further investigation.
Did you try whole blood? Chance: Was this with digitonin particles or intact mitochondria? A brief introductory sketch of the main relevant points in each of these pathways will first be given before proceeding to details. Though values for the content of cytochrome c reductase are known only for pig heart, the concentration in the tissues of both enzymes seems to be of the same order of magnitude. Martius: The constants have not yet been determined as far as vitamin K reductase is concerned. I doubt if anyone has tried it seriously. When two substrates compete for one common intermediary catalyst each by its presence creates unfavourable conditions for the reaction of the other substrate. Chance: It is important to make that distinction. When sectioned and studied by orthodox histological methods, cheek pouch connective tissue is seen to have an abundant and well differentiated fibre content.
Sugars identified in residues after lipid extraction: galactose, mannose, glucosamine, trace of glucose and fucose, possibly trace of galactosamine. We have been able to achieve good survival of homo- logous dissociated epidermal cells in filter chambers in the rabbit for about 21 days or so, but there is no consistent evidence that these chambers sensitize, which is a thorough confirmation of Algire Algire, G. The increased absorbancy at 430 mfx is suggestive of a transition in the mitochondria of state 3 to state 4. The electrode is polarized at —0-6 v and reduces oxygen to either peroxide or water, depending upon the experimental conditions at the tip of the electrode. Another point, following on what Dr.
Billingham: I couldn't exclude that possibility on the basis of our present knowledge. As a group, even the healthy homo- grafts showed more tendency to contract than did the isografts. You might find that these changed tumours would sensitize if you trypsinized the cells. The cells spleen or foetal Hver were inoculated 24 hours following X-irradiation, and the tumours were grafted subcutaneously immediately afterwards. This seems very improbable, because for saturation you will need at least a degree of isohaemagglutinins which will be detected serologically.
Experimental findings l The fate of cheek pouch skin isografts To provide the necessary controls, 40 C. They remained highly vascular, being flush pink in colour, and their hairless epithelial surface usually displayed a characteristic pattern of fme ridges or corrugations. I should like to comment also on a brief communication in a recent British Medical Journal Hackett, E. In low concentrations and with phylloquinone as acceptor this enzyme shows a turnover number of about 1,200,000 per molecule per minute. Furthermore Lejeune and Kandutsch this vol.
Thanks are due to Miss A. I think it still remains to be shown whether the entire cortisone effect on metastasis is not due to an inhibition of homo- graft reaction. Surely there must be a transitional stage between tolerance responsiveness and immune responsiveness. Boyse in unpubhshed work at this laboratory has subjected enhanced mammary tumours, dissociated by an enzymic method, to cytotoxic tests and found that no change in population susceptibility to isoantibody could be associated with enhanced growth. Starting with extracts of beef liver, which is the best source of this enzyme, an overall purification of more than 4,000-fold had to be performed before an electrophoretically pure pre- paration was obtained. In The Mechanism of Enzyme Action, p. Chance: Yes, this was actually mistaken for the reduced form.
But I should not say that they were conclusive. Description : Medical research systems in europeciba foundation symposium 21 new series pp 335 illustrated 1650 excerpta medica amsterdam 1973research and medical practice their interaction. There is no effect in the suspension to which no substrate has been added but which is rich in carbohydrate and lactate, or after addition of lactate or fumarate. Pathways of glucose metabolism in animal tissues. We have to keep in mind another possibility e. I quite agree that humoral antibody synthesis by transferred cells of tliis type ought to be measured but we have not yet done so.
Phosphorylase kinase was prepared according to Krebs and Fischer 1956. The main points are that proliferation is compelling if antibody production of the clone is to be increased from its usually sub-detectable level to one which is easily measurable whether in terms of cellular or humoral immunity , and that this proliferation brings the clone to occupy a much higher proportion of the total population of immuno- logically competent cells. The rejection of homo- grafts of both tumours by the genetically foreign spleen chimeras, and their progressive growth in the foetal liver chimeras, indicate that the immune response has been produced by the donor-type cells. The Foundation convenes many other in- formal discussions between research workers of different dis- ciplines and different nationalities and each year invites an outstanding authority to deliver a special lecture. BiUingham: It seems to be localized to the pouch. Baker's yeast suspended in phosphate buffer and aerated for 18 hours has a very low respiratory activity. The related enzymic changes are particularly clearly seen in Novikoff hepatoma where there is a very marked decrease in phospho- glucomutase activity to less than 10 per cent of that in normal liver and a complete absence of fructose diphosphatase, an enzyme of importance in the synthesis of glucose from pyruvate and lactate Weber and Cantero, 1957.
Krohn concerning the origin of placenta: if M. Control of Oxygen Utilization 101 and further oxidation in response to further additions of phosphate. Woodruff: There is a tendency to look at it that way, but I think it would be going much too far to suggest that the capacity for immuno- logical reaction is of no value for survival. In Biological Problems of Grafting, p. However, it is possible that the lipid material is more than an accidental contaminant of mitochrome. Similar con- clusions have recently been drawn from experiments with irradiated mitochondria Beyer, 1958 , and in bacterial systems, also, vitamin K is necessary for electron transport and phosphorylation, as has been shown by Brodie, Weber and Gray 1957. We have recently found it possible to dissociate the enzyme catalysing reaction 3 in soluble form from the digitonin fragments and have purified it substantially by classical fractionation methods.
Initiation of respiratory activity upon glucose addition is also a rapid but somewhat more complicated reaction Chance, 1954, 1955. Cooper, C, and Lehninger, A. After expenditure of the added. In order to illustrate the principles used, the measurements obtained from the remaining two assays have been plotted in Fig. Simonsen: I fmd it hard to beheve that it is all due to increased re- activity of cells which do not multiply. In this experiment the recipients had recently been sensitized to paternal antigens by A-strain skin grafts in order to accentuate any reaction which might occur.