Pressure and protein denaturation

Kinetic analyses have indicated that moderate hydrostatic pressures, up to some 700 atmospheres, oppose reversible and irreversible denaturations of certain enzyme systems, apparent at temperatures above the normal optimum of the enzyme reaction, as well as at lower temperatures in the presence of denaturants such as alcohol (1-4). Qualitative observations have shown that such pressures also retard the precipitation of highly purified human serum globulin and egg albumin at 65° (5) and slow the destruction of specific antitoxic activity at the same temperature (6). In this study we have obtained quantitative data with regard to the influence of various pressures, up to 10,000 pounds per sq. in., and of low concentrations of ethyl alcohol on the time course of precipitation of human serum globulin (1) at 65° and pH 6.0

The manufacture of antibodies in vitro

A protein solution with the properties of a specific antiserum to the triphenylmethane dye methyl blue has been made by treating a solution of bovine gamma-globulin and the dye with alkali and then slowly neutralizing the alkali. Some success has been obtained also in the formation of antibodies from other serum proteins and by other denaturation-renaturation procedures. By heating solutions of gamma-globulin and antigen to 57°C. for several days antisera homologous to the antigens have been prepared. This method has been used successfully with the azodye 1,3-dihydroxy-2,4,6-tri(p-azophenyl-arsonic acid) benzene and with pneumococcus polysaccharide Type III. The antipneumococcus sera were found to precipitate the polysaccharide of Type III but not those of Types I and VIII and to agglutinate pneumococci of Type III but not those of Types I and II

The retention of S35-labelled bovine serum albumin on normal and immunized rabbit liver tissue

The S35-label of S35-BSA was detected in the liver tissue of rabbits to the extent of 0.02 per cent (10 µg or sime 1014 molecules) of the injected material at 140 days after injection. The rate of loss of antigen at the termination of the experiment was of such an order that significant amounts would be expected to persist for at least several years. Data are reported which extend the retention data previously reported on S35-labelled hemocyanin. They indicate that amounts of the order of 0.05 per cent (25 µg.) of antigen material persist at 330 days after injection. All of the radioactivity of material retained in the liver tissue 6 weeks after injection was immunologically related to the original S35-BSA antigen. Preliminary studies are reported which indicate that the retained antigen is bound to ribonucleic acid. A new method is described for the isolation of p-azophenylsulfonate bovine serum albumin from tissue extracts by means of a Dowex 2 adsorbent

Heterologous carriers in the anamnestic antihapten response

Anamnestic antihapten responses were obtained to trinitrophenyl (TNP) when rabbits sensitized to trinitrophenyl-hemocyanin (TNP-KLH) were challenged with TNP-heterologous protein conjugates. Hapten-heterologous carrier conjugates elicited antihapten titers similar in magnitude to those elicited by the homologous carrier conjugate. Hapten-heterologous carrier recall of antihapten was successful as early as 37 days and as late as 11 months after sensitization. There was no correlation between anti-TNP-precipitating antibody titer after sensitization and the ability to respond to challenge by hapten-heterologous carrier. The results are discussed in terms of immunogenicity of sensitization, suppressive effects of persisting postsensitization antibody, and submolecular haptenic environment as factors possibly affecting the heterologous recall process

The biological activity of soluble antigen-antibody complexes: II. Physical properties of soluble complexes having skin-irritating activity

Previous work by Germuth and McKinnon (1), Trapani et al. (2), and ourselves (3) has established the fact that soluble antigen-antibody complexes formed in excess antigen can, (a) induce symptoms similar to anaphylaxis, (b) cause contraction of isolated smooth muscle from normal guinea pigs, and (c) increase the permeability of skin capillaries in a manner similar to that obtained in passive cutaneous anaphylaxis. These findings immediately raise many questions as to the fundamental mechanisms involved. For example, is the free antigen playing some role; is the toxicity dependent upon some change in the molecular structure of either antigen or antibody upon combination; is the complex itself toxic without any change in the molecular structure of the components; is the antigen-antibody ratio important; and, is complement involved? The work reported here involves a study of the possible role of free antigen and the nature of the complex. Some study was also made of untreated and decomplemented antiserums and, although there was no difference, this cannot rule out the possible participation of the test animal's (guinea pig's) own complement

Competition of haptens

Groups of rabbits were injected with either bovine serum albumin, sheep red cell stroma, or keyhole limpet hemocyanin to which 2,4-dinitrophenyl and/or p-azophenyl arsonate groups had been coupled. Groups of animals received either doubly coupled antigen or an equivalent mixture of singly coupled antigens. Materials were injected intravenously as a solution or subcutaneously and intramuscularly in complete Freund's adjuvant. The presence of dinitrophenyl groups on the immunizing antigen could suppress, partially or completely, the antibody response to p-azophenyl arsonate when this hapten was located on the same molecule. Suppression was dependent on the ratio of haptenic groups on the molecule, appeared to be greatly affected by the method of immunization, and could be demonstrated in all three antigen systems. Partial suppression was manifested in decreased frequency and delayed appearance of the response as well as decreased maximal antibody titers. These findings appear irreconcilable with the possibility of direct clonal selection of antibody-producing cells by unprocessed antigen

Qudit Colour Codes and Gauge Colour Codes in All Spatial Dimensions

Two-level quantum systems, qubits, are not the only basis for quantum computation. Advantages exist in using qudits, d-level quantum systems, as the basic carrier of quantum information. We show that color codes, a class of topological quantum codes with remarkable transversality properties, can be generalized to the qudit paradigm. In recent developments it was found that in three spatial dimensions a qubit color code can support a transversal non-Clifford gate, and that in higher spatial dimensions additional non-Clifford gates can be found, saturating Bravyi and K\"onig's bound [Phys. Rev. Lett. 110, 170503 (2013)]. Furthermore, by using gauge fixing techniques, an effective set of Clifford gates can be achieved, removing the need for state distillation. We show that the qudit color code can support the qudit analogues of these gates, and show that in higher spatial dimensions a color code can support a phase gate from higher levels of the Clifford hierarchy which can be proven to saturate Bravyi and K\"onig's bound in all but a finite number of special cases. The methodology used is a generalisation of Bravyi and Haah's method of triorthogonal matrices [Phys. Rev. A 86 052329 (2012)], which may be of independent interest. For completeness, we show explicitly that the qudit color codes generalize to gauge color codes, and share the many of the favorable properties of their qubit counterparts.Comment: Authors' final cop

The in vivo stability of antibody

Our previous studies, concerned largely with antigen retention and the characterization of antigen in tissues, led us to suspect that some antibody, like antigen, may be stabilized in tissue sites (1). The purpose of the present investigation was to study further, such antibody which appeared to be bound with antigen and perhaps normal tissue constituents. The investigation was carried out in the following manner: rabbits were first immunized by a series of intravenous injections of antigen and at the height of precipitin production they were fed S35-labelled yeast cells. Newly produced antibody, like the other plasma proteins, became readily labelled with S35 amino acids within a few hours. After varying lengths of time, when circulating antibody had declined, antigen was again injected. Serum samples were then taken at various intervals and the specific activity of antibody was measured as soon as antibody reappeared in the circulation. The specific activity of antibody was measured in the antigen-antibody precipitates obtained, both in the period when the antibody had been allowed to decline and also after antigen had been reinjected to induce an anamnestic response. A comparison of antibody-specific activity provided evidence that there was a release of antibody which had been made at the time of S35 feeding and stored in some stabilized form in tissues. The results are discussed with respect to the anamnestic response and the retention of antigen in tissues

EFFECT OF SECONDARY INJECTIONS OF ANTIGEN UPON THE RETENTION IN LIVER OF A PRIMARY INJECTION

The retention of antigen in rabbit liver tissue, resulting from a primary intravenous injection, is influenced by immunization brought about by subsequent intravenous injections of the same antigen. In rabbits given a single primary intravenous injection of radioactive antigen, the retention of radioactivity in liver tissue, after a period of 21 days, was greater than when the primary injection was followed by secondary injections of the same, but non-radioactive antigen. The results were similar for both S35-azohemocyanin and S35-azo-bovine-serum-albumin, except the hemocyanin was retained to a greater extent than the albumin. There was very little if any correlation between the number of secondary injections and retention of the initial injection. Quantitative antibody nitrogen data, obtained for the serum of each rabbit showed, in general, an inverse relationship between circulating antibody and radioactivity retained, i.e. the higher the circulating antibody titer, the lower the retention of radioactivity in liver tissue. Passively administered homologous antibody did not produce a change in the retention of the primary injection of antigen nor did secondary injections of a heterologous native protein injected according to the same immunization schedule as the homologous azoprotein. From these results it may be concluded that an intracellular antibody-forming activity influences the loss (or retention) of antigen deposited in liver tissue and that the mechanism is immunologically specific

URINARY EXCRETION OF FOREIGN ANTIGENS AND RNA FOLLOWING PRIMARY AND SECONDARY INJECTIONS OF ANTIGENS

Two soluble antigens, BSA and KLH labeled with sulfanilate-35S, when injected intravenously into normal animals, were excreted in the urine to over 70% in 24 hr. Over the next 6 days, 25% more was excreted after which time only a trace could be detected. Much of the antigen remaining from the primary injection appeared in the urine following a secondary injection of the unlabeled protein carrier at 7 days after primary injection. The antigen material found in the urine was quite heterogeneous with respect to physical properties and much of it was associated with RNA material as shown by chromatographic analyses. The main difference between the labeled material released following the primary and secondary injection was the higher degree of association of antigen material with nucleotide material after secondary injection as compared with primary injection. Further study is needed to distinguish qualitative from quantitative changes of the components, antigen and nucleic acid, and also the nature of their association. Possible similarities were found for the RNA-antigen material released from tissue after secondary injection of unlabeled antigen, and the material that was isolated previously from liver