TISSUE PERMEABILITY AND THE SPREADING FACTORS IN INFECTION : A Contribution to the Host:Parasite Problem.

Nature of collagen diseases.

The Newer Knowledge of Bacteriology and Immunology

Publisher Summary The principles of measuring the concentration of virus particles are based on the techniques evolved for counting bacteria. In this chapter, the principles are discussed along with their application to certain animal viruses. Three aspects of this subject are discussed: (1) measurement of the infectivity titer of a preparation, (2) measurement of the total number of virus particles in a preparation, and (3) calculation of the ratio of the infectivity titer to the virus particle count and the significance of different ratios. There are three types of method used for measuring virus infectivity: direct method, all-or-none response method, and indirect methods. Measurement of the total number of virus particles in a preparation includes those methods in which the particles can be seen and counted directly in the electron microscope such as calculations from the mass, volume, and density. Direct methods (including electron microscopic enumeration) and indirect methods (dosage–response curve) are used. It is suggested that virus particle counting techniques may be useful in searching for incomplete forms of other viruses, and in trying to elucidate which properties of the virus particles and which cell constituents are important in determining what will be the end result of the virus-cell interaction.

Particle counts and infectivity titrations for animal viruses.

Male mice have been noted to be more susceptible to encephalomyocarditis (EMC) virus than female animals. Castration of male mice abolished this difference and resulted in enhanced resistance similar to that of female mice. This increase in resistance in castrated males could be eliminated by adrenalectomy. Adrenalectomy alone increased susceptibility in male mice but not in female mice. The administration of a long-acting preparation of testosterone markedly increased susceptibility both in castrated male and female mice, as well as in intact females. Testosterone also had a similar effect in immature mice of both sexes. On the other hand, estradiol, but not progesterone, increased susceptibility to EMC virus in castrated mice of both sexes. These data indicate that testicular, ovarian, and adrenal hormones may influence resistance to EMC virus in the mouse and may be critical determinants of the clinical outcome of infection with this virus.

https://iai.asm.org/content/iai/5/5/637.full.pdf

Differential susceptibility of male and female mice to encephalomyocarditis virus: effects of castration, adrenalectomy, and the administration of sex hormones.

The essential findings of these experiments may be summarized as follows: The estrogenic hormone after being given for 1 week slows up the spread of India ink but allows it to reach and exceed a normal spread after 24 hours. After injections of the estrogenic hormone for 3 weeks the spread of India ink is much less than in the control animals. The resistance of the rabbit to vaccinia is increased if the rabbit has been castrated and then given the estrogenic hormone for a period of 3 weeks before being vaccinated. At the present time nothing can be said about the action of the gonadotropic hormone on India ink, as the experiments did not agree.

https://rupress.org/jem/article-pdf/67/1/159/1181136/159.pdf

Studies on the relationship of the sex hormones to infection : i. the effect of the estrogenic and gonadotropic hormones on vaccinia and the spreading factor.

In a recent publication (1), we reported that the estrogenic hormone, when injected into castrate rabbits, decreased the spread of India ink and increased the resistance of the rabbit to infection with vaccinia. In another paper, pseudopregnancy was shown to decrease the spread of India ink (2). In these papers, we cited a number of other workers who had shown that related endocrine states caused a change in the resistance of the host to infection. A further study of the relationship of the endocrine pattern of the host to infection was considered desirable. The value of such a study would be greatly enhanced, furthermore, if the resistance of the host could be determined on a quantitative basis. The only report of a quantitative study which we found was the paper by Rosahn, Hu and Pearce (3). These workers showed by the statistical analysis of data derived from a large number of rabbits that pregnancy increases the resistance of rabbits to infection.

Studies on the Relationship of Sex Hormones to Infection III. A Quantitative Study of the Increased Resistance to Vaccinial Infection Produced by the Estrogenic Hormone and Pseudopregnancy

Experiments are reported which show that the virulent Bordet-Gengou bacillus can produce a significant lymphocytosis and an interstitial mononuclear pneumonia in both the monkey and the rabbit. Both of these reactions occur apparently as the result of a toxic material formed in vivo from the Bordet-Gengou bacillus and are not dependent on the multiplication of the organism itself. It was also shown that the strictly avirulent form could also cause an interstitial mononuclear pneumonia but no lymphocytosis. This interstitial mononuclear pneumonia was thought to be the result of the foreign substance produced by the organism when it was in this stage. This was substantiated by the fact that this lesion could be produced both by living and dead organisms.

/pdf/results-of-the-intratracheal-injection-of-the-bordet-gengou-5d1pvmnabr.pdf

Results of the intratracheal injection of the bordet-gengou bacillus in the monkey and rabbit

IN RECENT YEARS it has become increasingly evident that sex and certain endocrine states play an important role in the host's response to disease incitants. Schultz (i) in 1934 reported that factors associated with sexual maturity in females reduces their reactivity to serum. Recently von Hamm and Rosenfeld (2) have reported that theelin affects antibody formation in pneumococcus infections. In preceding papers we have shown that pregnancy (3) pseudopregnancy (4) and the estrogenic hormone (5) modify the rabbit's response to viral infection. It was also found that there is a close correlation between the spread of India ink in the skin and the rabbit's susceptibility to infection. This is in line with the findings of DuranReynals (6). In these papers we have extensively reviewed the literature and these references will not be repeated here. It was found early in the course of this work that extreme variations occurred in SO-Called normal

Studies on the relationship of sex hormones to infection iv. a study of the dispersion or concentration of india ink in skin by certain sex hormones1,2

SEVERAL YEARS ago one of us (i) reported that pregnancy in rabbits altered the reactivity of the tissues to the virus of infectious myxomatosis. In the first paper of this series (2) we showed that the injection of estrone into castrated male rabbits decreased the spread of India ink in the skin and also increased the rabbits'resistance to infection with vaccinia. These papers together with the literature indicate that variations in the sex hormones can cause modification in the susceptibility of the rabbit to infection. This fact seemed of sufficient importance to warrant further study. In the present experiment we have thought it desirable to learn more concerning the spread of materials in the normal animal before continuing the study of changes produced by the injection of the various hormones. Pseudopregnancy in the rabbit offered an excellent opportunity for this study, since it is not complicated by the presence of a fetus and a placenta

Studies on the relationship of the sex hormones to infection ii. the effect of pseudopregnancy on the spread of india ink in the skin of rabbits

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