Somatic Proteins Research Articles

Immunological characterization of the entomopathogenic hyphomycetes Beauveria and Metarhizium

Immunological comparison among Beauveria species and Metarhizium strains isolated from insect larvae were made using immunoelectrophoresis. Antigens consisted of somatic or metabolic buffer-soluble proteins. Antisera were produced in rabbits against each of the 6 fungal strains. Each antigen was tested against the homologous antiserum non-adsorbed or cross-adsorbed with one other antigen and against the heterologous antisera. The immunoelectrophoresis slides were analyzed in terms of the number of precipitin arcs obtained with cross-reacting and reference antigens, with any one antiserum. Immunoelectrophoregrams were also considered.

Gluconeogenesis, ureagenesis, and ketogenesis during sepsis.

Abstract : Acute sepsis is characterized by an accelerated catabolism of somatic proteins, an increased rate of oxidation and transamination of branched-chain amino acids within muscle, an enhanced formation of lactic acid, alanine and glutamine in muscle, an enhanced flux of these substrates from muscle to liver, and an acceleration of the synthesis and release of glucose from the liver. Endocrine responses which influence these metabolic changes include an enhanced secretion of both insulin and glucagon from pancreatic islet cells and a resultant decrease in the molar ratio of insulin to glucagon in plasma. The secretion of the adrenal glucocorticoids and growth hormone are increased as may be the secretion of catecholamines. The accelerated release of glucose from the liver is generally accompanied by an increase in glucose pool size and an increase in the rate of glucose utilization as a cellular fuel. The hormonal, enzymatic, and substrate interrelationships within the liner combine in their effects to inhibit Ketogenesis and stimulate hepatic lipogenesis during acute sepsis.

Somatic mutations and proteins.

A large body of data has now been accumulated concerning the ways in which heritable mutations can affect protein structure. Such mutations are usually presumed to arise in the germ line, and are studied by progeny analyses of various types. Today, I would like to consider how somatic mutations might be genetically predisposed and thereby made available to an organism during its adaptation to environmental hazards or during its development. The highly specialized immune system of higher animals can profitably be discussed from this viewpoint, and I shall describe a possible molecular mechanism (Smithies 1965) for implementing the immune response, and then consider very briefly its relevance to other adaptive and developmental processes. The immune response The essential questions which are posed by the immune system can be stated simply: (i) How can many different antibodies be specified by an initially fixed genetic endowment? (ii) How can selection be made against anti-self antibodies and for anti-foreign antibodies? (iii) How can an antigen instruct the organism to respond more effectively to repeated encounters with the same foreign substance? (i) Antibody variability could be the consequence of the organism having a relatively large number of related but not identical genes in the initial zygote from which to select combinations forming useful antibodies. This possibility is un­attractive for reasons of economy, and such a system would probably be genetic­ally unstable. I have consequently preferred to explore one of many alternative possibilities, namely that there are a limited number of genetic loci determining antibody structure which have evolved so that they can provide many different proteins as a result of genetically predisposed somatic mutations.

A METHOD OF TYPING HAEMOPHILUS INFLUENZAE BY THE PRECIPITIN REACTION

A method of typing H. influenzae by the precipitin reaction is described. The procedure consists of dissolving the bacterial culture in 90% phenol to destroy the specificity of the somatic proteins followed by alcoholic precipitation of the denatured proteins and type specific polysaccharide. The carbohydrate is extracted from the precipitate with saline and portions of the saline extract added to samples of the six type specific antisera. A positive test is indicated only by a marked turbidity, which develops within five minutes after mixing and denotes the extraction of at least 0.01 mgm. of polysaccharide. A strong positive test is, of course, regularly obtained in the case of cultures shown to be encapsulated by the usual capsular swelling technique. However, the method was devised as an attempt to ascertain whether non-typable (by the capsular swelling technique) derivatives of strains of known type or non-typable, but suspected respiratory pathogens, isolated from clinical material, contained detectable quantities of any of the known type specific polysaccharides.

Value of H and O Agglutination in Diagnosis of Typhoid

Since the advent of prophylactic vaccination against typhoid fever, the interpretation of agglutination reactions has been confusing. This is due to the fact that the serum of inoculated persons will agglutinate the organism in question. In view of this fact Dreyer introduced his method of repeated estimation of the agglutinin content of the patient's serum. However, in the case of Salmonella paratyphi (B. paratyphosus A), the agglutinin response may be so slight as to render the repeated estimations uncertain. Recently, Felix published evidence to show that protective inoculations lead to the formation of large flaking agglutinins, while the agglutination in typhoid fever and in a non-inoculated person is, without exception, of the small flake type. The explanation of the small and large flaking forms is found in the work of Weil and Felix who showed that Proteus X exists in two forms (0 and H forms), which differ from each other morphologically, biologically and serologically. They represent two forms of variation mutually transferable into each other. The anti-O-serum contains one agglutinin which reacts specifically with the homologous organisms agglutinating them in small flakes (O-agglutination); antiserum against the H type contains two agglutinins, the specific small flaking O and a nonspecific large flaking H which reacts with heterologous as well as with homologous organisms. The 0 receptors are thermostabile while the H receptors are thermolabile (Sachs). Burnet believed that the O types are due to the somatic proteins, and the H type to the flagellar proteins. Accordingly,

Renaissance of Pre-Ehrlich Immunology

Summary There is convincing evidence that injected antigens undergo a series of chemical “hybridizations” in animal tissues, and suggestive evidence that the resulting antigen-tissue “hybrids” become semi-permanently “symbiotic” with these tissues, both terms, of course, being used metaphorically. Whether or not these “symbiotic hybrids” are to be regarded as partially homologized antigens, as specifically alienated somatic proteins (30), or as antigen-somatic-protein conjugates can not be predicted from present biochemical knowledge. There is convincing evidence that some of these antigen-tissue “hybrids” have properties simulating those of specific antibodies, but no proof thus far that they are identical with these antibodies. There is, however, no evidence at the present time that there is any other physiological method of specific antibody formation.