The Journal of Experimental Medicine

Salvin, S. B.; Smith, Robert F.

doi: 10.1084/jem.109.4.325pmid: 13641560

The induction of delayed type of hypersensitivity to diphtheria toxoid in the guinea pig was not inhibited by total body irradiation up to 300 r in intensity. X-ray doses of 200 to 300 r administered about 18 hours before sensitization caused the period of delayed hypersensitivity to be extended to the 19th to 21st day postsensitization in. the absence of circulating antibody. X-ray doses of 50 to 100 r caused a decrease in the titer of circulating antibody, although delayed hypersensitivity lasted for a normal time. When 300 r irradiation was administered 18 hours after sensitization, delayed hypersensitivity lasted for the usual period and circulating antibody first appeared at the usual 13 to 14 days after sensitization. Introduction of normal serum or leucocytes into irradiated animals apparently did not reduce damage to the mechanism regulating the rate of antibody synthesis. Footnotes Submitted: 26 October 1958

Hall, Charles H.; Atkins, Elisha

doi: 10.1084/jem.109.4.339pmid: 13641561

Evidence has been presented that the fever elicited by intravenous administration of old tuberculin (O.T.) in BCG-infected rabbits is a specific property of this hypersensitivity system and is probably not due to contamination of tuberculin with bacterial endotoxins. Daily injections of O.T. in sensitized animals resulted in a rapid tolerance to its pyrogenic effect. Tuberculin tolerance can be differentiated from that occurring with endotoxins and was invariably associated with the development of a negative skin test. The mechanism of this tolerance would thus appear to be desensitization. A circulating pyrogen found during tuberculin fever was indistinguishable in its biologic effects from endogenous pyrogens obtained in several other types of experimental fever. This material produced fevers in normal recipients and therefore may be clearly differentiated from O.T. itself which was pyrogenic only to sensitized animals. Since the titer of serum pyrogen was directly proportional to the degree of fever induced by injection of O.T. in the donor animals, a causal relation is suggested. On the basis of these findings, it is postulated that tuberculin fever is due to a circulating endogenous pyrogen released by a specific action of O.T. on sensitized cells of the host. Footnotes Submitted: 11 December 1958

McCarty, Maclyn

doi: 10.1084/jem.109.4.361pmid: 13641562

A bacterial substance has been described which gives a precipitin reaction with certain antisera to Group A streptococci. The precipitating antigen is present in various Gram-positive bacteria, including most hemolytic streptococci, staphylococci, and aerobic sporulating bacilli. It is not present in any of the Gram-negative species examined or in pneumococci, clostridia, or corynebacteria. Analysis of purified preparations obtained from Group A streptococci indicates that the antigen is a simple polymer of glycerophosphate. The identification has been confirmed by immunochemical studies, including precipitin tests and specific inhibition with synthetic polyglycerophosphates. In addition, the infrared spectra of bacterial and synthetic polyglycerophosphate are shown to be closely similar. Immunochemical analysis suggests that the amount of polyglycerophosphate present in Group A streptococci and staphylococci is approximately 1 per cent of the dry weight of the cells. The cellular localization and function of the polyglycerophosphate have not been established. Footnotes Submitted: 18 December 1958

Rowe, Wallace P.; Hartley, Janet W.; Estes, John D.; Huebner, Robert J.

doi: 10.1084/jem.109.4.379pmid: 13641563

Three procedures have been compared for usefulness in titration and detection of polyoma virus: production of cytopathic effect (CPE) in mouse embryo tissue culture, production of HI antibody after inoculation into weanling mice (MAP test), and production of tumors in suckling hamsters during a 3 to 5 week observation period. The tissue culture and mouse antibody production tests were generally comparable in sensitivity, reproducibility, and time required to obtain results. Titration by tumor production in suckling hamsters was not suitable for quantitation because of marked variation in susceptibility among animals. Virus was detected in tissues of normal mice from spontaneously infected colonies by either production of CPE in mouse embryo tissue culture or by the MAP test; virus was found in organs of 15 (58 per cent) of 26 mice with antibody, and 2 (8 per cent) of 24 mice without antibody. Footnotes Submitted: 2 December 1958

Itoh, Heihachi; Melnick, Joseph L.

doi: 10.1084/jem.109.4.393pmid: 13641564

Virus particles derived from single cells infected with two enteroviruses have been studied. Evidence was obtained to indicate that phenotypic, but not genotypic, mixing occurs between Coxsackie A9 (CAP) and ECHO 7 (E7) viruses. Monkey kidney cultures in monolayer were doubly infected with high multiplicities of CA9 and E7 viruses. During the latent period, the infected cells were suspended, diluted, and distributed under oil into droplets each containing a single cell, as checked by microscopic observation. The virus particles released by individual cells into the microdrop were characterized in differential plaque neutralization tests. Fifteen per cent of the microdrops contained doubly neutralizable particles, 53 per cent yielded either CA9 or E7 particles, and 34 yielded particles of an intermediate character (deficits between 37 and 75 per cent). On passage, the doubly neutralizable particles yielded progeny of both parental types. All passage strains behaved like the corresponding parent strain as regards pathogenicity for newborn mice, which is to say that this property was limited to virus particles with CA9 antigenicity. Coxsackie A9 has a more rapid growth cycle than ECHO 7 in rhesus monkey kidney cell cultures, and a slower one in patas cultures. In rhesus, when E7 virus was added first, CA9 could be added up to 2 hours later, and still a significant number of cells yielded either CA9 or doubly neutralizable virus. The converse was observed in patas cells. Footnotes Submitted: 17 December 1958

Ginsberg, Harold S.; Dixon, Mary K.

doi: 10.1084/jem.109.4.407pmid: 13641565

During a single cycle of multiplication of type 4 adenovirus in HeLa cells an average 2-fold increase in total DNA occurred over that measured in uninfected cells. Of the total DNA from infected cells about 23 per cent was extractable into 0.15 M NaCl, a quantity approximately four and a half times greater than that of the DNA obtained from normal cells in 0.15 M NaCl. Ninety to 99 per cent of infectious virus was also extracted into the 0.15 M NaCl fraction. Concurrently with the accumulation of DNA in virus-infected cells there occurred a 2-fold increase in total protein. The proportionate increases in protein were approximately equal in 0.15 M NaCl and water extracts of infected cells. High speed centrifugation indicated that the bulk of the DNA and protein was not directly associated with infectious viral particles. Although in virus-infected cells a markedly increased synthesis occurred of a DNA which had solubility properties different from the major portion of normal host DNA, nucleotide analysis did not reveal any other qualitative differences. However, a marked change in nucleotide molar ratios was observed in the 0.15 M NaCl-soluble DNA from virus-infected cells. It seems apparent from the findings that the biochemical alterations found in HeLa cells infected with type 4 adenovirus are intimately related to the infectious process. Footnotes Submitted: 16 November 1958

Noyes, Wilbur Fiske

doi: 10.1084/jem.109.4.423pmid: 13641566

A method has been devised to determine the location of infective Shope virus in the papillomas of cottontail rabbits. Frozen sections of the growths were burned selectively with a microcautery to destroy either the keratinized or proliferating layer and the sections were then applied directly to the sensitized epidermis of domestic rabbits. No papillomas appeared when the keratohyaline and keratinized areas had been eliminated leaving the proliferating cell layer, whereas papillomas arose when the proliferating cell areas were destroyed leaving the keratohyaline and keratinized layers. The results indicate that infective Shope papilloma virus is situated mainly, perhaps entirely, in the keratohyaline and keratinized areas of cottontail papillomas. This is in accord with the previous disclosure by the fluorescence technique that virus antigen in demonstrable quantity is present only in these situations. Footnotes Submitted: 24 November 1958