The Extent of Local Dispersion of Infectious Agents as a Factor in Resistance to Infection

Abstract

The reactions of the host to bacterial and virus infections have been measured in terms of the minimal lethal dose for different sites of inoculations, and they have been appraised in terms of damage to tissues and in terms of tissue specificity; but the extent of dispersion of the infective agents as affecting the results has in the past been accorded little attention. In recent work from this laboratory a chemical fraction which causes dispersion of particulate matter injected with it into the skin and extracts from testicle (1) and from invasive bacteria (2), which have the same effect, served as a tool to show that the extent of dispersion of the infectious agent importantly influences the size of the lesions due to infection. It was found that intracutaneous inoculations into rabbits of testicle extract together with concentrated suspensions of bacteria resulted in more widespread lesions than inoculations of equally concentrated suspensions of bacteria in isotonic saline (3). It was later observed that inoculations of testicle extract with dilute suspensions of staphylococcus either produced lesions which were less widespread than those produced by saline suspensions or failed to produce a lesion (4). These results led to the supposition that in the case of bacteria there could be determined a critical concentration, the minimal effective concentration per unit area of infection, below which no reaction would occur, and above which the intensity of the reaction would be roughly proportional to the concentration. The critical concentration is presumably the resultant of local resistance of the host tissues, and of local virulence of the bacteria.

Tissue Permeability and the Spreading Factors in Infection 1

“…from testicle (50, 55, 150, 159, 151), snake venom (61), staphylococcus (54), and by azoproteins (38,40) tested on the skin of rabbits and guinea pigs. The group includes the viruses: vaccinia (50,150,55,93) herpes, vesicular stomatitis (110), rabbit fibroma (55), rabbit myxoma (213), Rous sarcoma (113,66) and virus III (55).…”

“…This concept was evolved from studies in our laboratory in which the S.F. was employed as a tool for studying the effects of the local on September 23, 2020 by guest http://mmbr.asm.org/ Downloaded from dispersion of the infectious agent as a factor in resistance to infection (53,55). The results obtained in bacteria can be summarized as follows:…”

Tissue Permeability and the Spreading Factors in Infection

“…This concept was evolved from studies in our laboratory in which the S.F. was employed as a tool for studying the effects of the local on December 13, 2020 by guest http://mmbr.asm.org/ Downloaded from dispersion of the infectious agent as a factor in resistance to infection (53,55). The results obtained in bacteria can be summarized as follows:…”

The Degree of Dispersion of the Bacillus as a Factor in Infection and Resistance in Experimental Tuberculosis

“…The spreading agent used throughout this investigation was testicle extract. The fact that this extract acts by markedly increasing the permeability of the tissues has been proven in a series of studies (5)(6)(7)(8).…”