Tubercle bacilli of the pathogenic human strain H37Rv had previously been shown to multiply, after ingestion by cultured mouse peritoneal macrophages, within phagosomes that tended to remain unfused with secondary lysosomes. Means were sought therefore for promoting experimentally a modification of the host response so as to attain a high level of phagolysosome formation, enabling tests to be made of any effects on the course and outcome of the intracellular infection. This was achieved by exposing viable bacilli to specific rabbit antiserum before their ingestion. Quantitative assessments, using electron microscopy, now showed that a majority of the phagosomes containing intact bacilli had fused with ferritin-labeled lysosomes, and frequently the fusion was massive. Bacterial viability studies established that the serum pretreatment was not itsel bactericidal. In the course of progressive infections with strain H37Rv, monitored by counts both of viable bacterial units and of intracellular acid-fast organisms, no appreciable difference was found between the intracellular growth rates of control and antiserum-treated bacilli. Concurrent electron microscopy showed that bacilli could remain intact and multiply both in phaagolysosomes and in unfused phagosomes, ruling out the possibility of selective growth of antiserum-pretreated bacilli within the minority of phagosomes that remained unfused. It was concluded that "turning on" phagosome-lysosome fusion in normal macrophages did not influence the outcome of infection with virulent M. tuberculosis; lysosome contents manifestly failed to exercise an antibacterial effect on this organism. Nevertheless, the possibility remains that the lysosomes of specific immune macrophages have antituberculous potentiality. In that case the experimental "turning on or off" of fusion could be a decisive factor in the outcome of a virulent challenge. Should it not be, the antibacterial capabilities of immune cells would need to be ascribed to factors other than lysosomal attack, the latter being essentially for disposal of the dead organisms.

https://rupress.org/jem/article-pdf/142/1/1/1267442/1.pdf

Phagosome-lysosome interactions in cultured macrophages infected with virulent tubercle bacilli. Reversal of the usual nonfusion pattern and observations on bacterial survival.

The authors argue that plague should be taken much more seriously by the international health community.

/pdf/plague-past-present-and-future-4yvkf2520n.pdf

Plague: past, present, and future.

A. Macrophage-Dependent Resistance in the Absence of Specific Immune Responses.... 1223 B. Augmentation of Macrophage Numbers by Local Proliferation and Influx of Monocytes from the Blood 1223 C. Granuloma Formation 1224 D. Macrophage Activation 1224 E. The Genetic Basis of Mononuclear Phagocyte-Dependent Resistance ......... 1226 F. Role of Polymorphonuclear Leukocytes .... 1226

The Role of Cell-Mediated Immunity in Bacterial Infections

Brucellosis vaccines: past, present and future.

(1973). Bacterial Assimilation of iron. CRC Critical Reviews in Microbiology: Vol. 2, No. 3, pp. 273-331.

Bacterial Assimilation of iron

Comparison of the Brucella-immune and the BCG-immune histiocyte, each of which is resistant to necrotization by either Brucella or mycobacteria, has revealed a number of dissimilarities in their behavior. The Brucella-immune histiocyte was found to be incapable of transferring its resistance to the cells of normal animals; it was also unable to achieve attenuation of virulent tubercle bacilli. In contrast, the BCG-immune histiocyte and certain of its subcellular components (ribosomes and ribosomal RNA) were effective in inducing cellular resistance in normal animals against both Brucella and mycobacteria. When RNA was used, only immune ribosomal RNA was effective; when intact ribosomes were used, both immune and recipient ribosomes proved active. These investigations have also shown that the resistance of the BCG-immune histiocyte against Brucella and mycobacteria was of long duration and not readily dissociable.

https://rupress.org/jem/article-pdf/120/5/885/1081748/885.pdf

Studies of Tubercle Bacillus-Histiocyte Relationships. VIII. Comparative Study of Cellular Resistance induced by Brucella and Mycobacteria.

Glenchur et al. [1] demonstrated that Brucella melitensis produces as many as 36 precipitinogens, varying considerably in quantity with the different strains. They also showed [2] that the soluble constituents of B. melitensis induce antibodies active in agglutination, precipitation, blocking reactions, and cutaneous hypersensitivity. Other workers [3-7] developed a passive hemagglutination test for Brucella infection and immunity studies. Diaz et al. [8] studied in detail 2 antigenic preparations involved in the passive hemagglutination test: the NaOH-treated etherwater extract (EW-T) of smooth Brucella and the water-soluble extract of sonic-vibrated smooth or

Immunization against Brucella infections: serological and immunological studies on a soluble antigen from Brucella melitensis.

Serum-mediated immune cellular responses to Brucella melitensis. 7. The separation and assay of serum globulins responsible for macrophage stimulation and Brucella inhibition.

An effort has been made to increase our knowledge of the proliferating capacity of the rabbit peritoneal histiocyte which we have employed for several years in a study of the infection process by species of Brucella and Mycobacterium.l-3 Conflicting results and interpretations of data obtained from cell cultures concerning the response of host cells in vitro to Brucella infection' 5revealed a need for attention to the fate of the host cell.6 Results obtained from experiments employing "flying coverslip" techniques differ in kind and degree from results obtained in microchambers such as the Mackaness cell. It therefore seemed to be of importance to learn the extent of the histiocyte's ability to multiply under the conditions of "flying coverslip" technique, employing autoradiography with tritium-labeled thymidine to attempt to define the proliferative tendencies of the rabbit peritoneal histiocyte. A later report will compare in detail the behavior of histiocytes in both kinds of cell maintenance conditions.

Proliferation of rabbit peritoneal histiocytes as revealed by autoradiography with tritiated thymidine

Ultrastructural identification and localization of the fraction 1 "envelope" antigen in the plague bacillus Yersinia pestis were the primary objectives of this brief study. The antigenicity of extra-cellular material between the bacilli in undisturbed cultured colonies and that of the pathogen per se were measured and correlated by means of the semi quantitative complement fixation method after incubation for 72 h at 37 C. When the amount of extracellular substance in wild-type T1 (virulent) bacteria was compared by electron microscopy with that in avirulent strains of Y. pestis, with and without passage through guinea pigs, we found that the material of interest was greatly attenuated or even absent in colonies that had not been passed through animals, whereas passage markedly augmented production of the material. We also explored the requirement for larger quantities of Ca(2+) and Mg(2+) in the culture media and discovered that without these ions production of the extracellular material was limited. These observations support the hypothesis that this extracellular substance between cultured Y. pestis bacilli of various strains represents the source of the fraction 1 envelope antigen.

https://iai.asm.org/content/iai/11/6/1382.full.pdf

Sanford S. Elberg

Papers

Studies of Tubercle Bacillus-Histiocyte Relationships. VIII. Comparative Study of Cellular Resistance induced by Brucella and Mycobacteria.

Immunization against Brucella infections: serological and immunological studies on a soluble antigen from Brucella melitensis.

Serum-mediated immune cellular responses to Brucella melitensis. 7. The separation and assay of serum globulins responsible for macrophage stimulation and Brucella inhibition.

Proliferation of rabbit peritoneal histiocytes as revealed by autoradiography with tritiated thymidine

Yersinia pestis: Correlation of Ultrastructure and Immunological Status