Aberrant oxygen metabolism in neoplastic cells injured by cytotoxic macrophages.
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Animals↗
Biomedical subjects
D L Granger
Publications and source records attributed to D L Granger.
Virulence of Cryptococcus neoformans. Regulation of capsule synthesis by carbon dioxide.
Cryptococcus neoformans is variably encapsulated in vitro, whereas in tissues it develops a large capsule. We observed that cells of a strain with thin capsules, when growing in a standard fungal culture medium, became heavily encapsulated when incubated in serum-free cell culture medium (Dulbecco's modified Eagle's medium [DME]). Capsule size was quantitated physically by measuring cell volume, and chemically by determining the content of a capsular monosaccharide, glucuronate. The CO2/HCO-3 couple stimulated capsule development, resulting in visible enlargement by 3 h after exposure to high CO2/HCO-3. The amount of capsule per cell was directly proportional to the total millimolar CO2/HCO-3 concentration between 24 and 2.4 mM at pH 7.35, but at constant PCO2 (40 torr) and varying [HCO-3], the cells were heavily encapsulated down to pH 6.8. Concentration of CO2/HCO-3 in the physiologic range increased elaboration of polysaccharide into the medium and slowed the cell generation time from 2 to 6 h. Four other first-passage clinical isolates were all heavily encapsulated in DME with CO2/HCO-3, but variably encapsulated in DME without CO2/HCO-3. Exposure of yeast to increased CO2/HCO-3 caused a marked reduction in complement-mediated phagocytosis by mouse macrophages. A stable clone was isolated which contained capsular polysaccharide, but lacked the CO2-inducible phenotype. This clone was avirulent for steroid-treated rabbits. Thus, the prevailing CO2 concentration in mammalian tissues may be one stimulus for capsular polysaccharide synthesis. This could serve as an adaptive mechanism favoring parasite survival in the host.
Animals↗
Secondary syphilis masquerading as AIDS in a young gay male.
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Acquired Immunodeficiency Syndrome↗
Activated macrophage mediated cytotoxicity for transformed target cells.
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Animals↗
Sites of inhibition of mitochondrial electron transport in macrophage-injured neoplastic cells.
Previous work has shown that injury of neoplastic cells by cytotoxic macrophages (CM) in cell culture is accompanied by inhibition of mitochondrial respiration. We have investigated the nature of this inhibition by studying mitochondrial respiration in CM-injured leukemia L1210 cells permeabilized with digitonin. CM-induced injury affects the mitochondrial respiratory chain proper. Complex I (NADH-coenzyme Q reductase) and complex II (succinate-coenzyme Q reductase) are markedly inhibited. In addition a minor inhibition of cytochrome oxidase was found. Electron transport from alpha-glycerophosphate through the respiratory chain to oxygen is unaffected and permeabilized CM-injured L1210 cells oxidizing this substrate exhibit acceptor control. However, glycerophosphate shuttle activity was found not to occur within CM-injured or uninjured L1210 cells in culture hence, alpha-glycerophosphate is apparently unavailable for mitochondrial oxidation in the intact cell. It is concluded that the failure of respiration of intact neoplastic cells injured by CM is caused by the nearly complete inhibition of complexes I and II of the mitochondrial electron transport chain. The time courses of CM-induced electron transport inhibition and arrest of L1210 cell division are examined and the possible relationship between these phenomena is discussed.
Animals↗
Induction of resistance to tuberculosis in mice with defined components of Mycobacteria and with some unrelated materials.
Factors contributing to protection against experimental tuberculosis have been studied with refined and well-characterized fractions from mycobacteria and with certain unrelated antigens. Mice were vaccinated intravenously with various combinations of materials presented on minute oil droplets in saline emulsion and were later challenged by aerosol. The minimal composition of an effective vaccine was P3 (a trehalose mycolate similar to cord factor) plus an antigen, which could be tuberculo-protein, or a low-molecular-weight tuberculin-active peptide, or unrelated antigen such as bovine serum albumin or bacterial endotoxin. Development of a hypersensitivity granuloma in the lungs appeared to be essential to protection in this laboratory model.
Animals↗
Induction of resistance to tuberculosis in mice with defined components of mycobacteria and with some unrelated materials.
Factors contributing to protection against experimental tuberculosis have been studied with refined and well characterized fractions from mycobacteria and with certain unrelated antigens. Mice were vaccinated intravenously with various combinations of materials presented on minute oil droplets in saline emulsions and were later challenged by aerosol. The minimal composition of an effective vaccine was P3 (a trehalose mycolate similar to cord factor) plus an antigen, which could be tuberculoprotein, or a low-molecular-weight tuberculin-active peptide, or unrelated antigen such as bovine serum albumin or bacterial endotoxin. Development of a hypersensitivity granuloma in the lungs appeared to be essential to protection in this laboratory model.
Animals↗
Inhibition of pulmonary granuloma formation in mice by treatment with Mycobacterial protoplasm and immuno-suppressants and its relation to protection against aerosol infection with virulent Mycobacterium tuberculosis.
Because the pulmonary granuloma formation by mycobacterial cell walls (CW) is likely mediated by cellular immunity, the effect of specific antigens and various immunosuppressants on pulmonary granuloma formation and protection against virulent m. tuberculosis, strain H37Rv was investigated in mice immunized with oil-treated CW from BCG or M. Tuberculosis, strain Aoyama B. Results of desensitization experiments with specific antigens showed that multiple intravenous injections of BCG protoplasm inhibited the footpad delayed hypersensitivity, macrophage migration inhibitory activity of lung cells and pulmonary granuloma formation as well as the enhancement of resistance against aerosol challenge with M, tuberculosis, strain H37Rv. However, treatment with nonspecific immunosuppressants like con A, silica or carrageenan induced only abrogation of footpad delayed hypersensitivity but not prevention of pulmonary granuloma formation or resistance against aerosol challenge. These results suggest a close relationship between pulmonary granuloma formation and protection against H37Rv in mice immunized with oil-treated mycobacterial CW.
Aerosols↗
Injury of neoplastic cells by murine macrophages leads to inhibition of mitochondrial respiration.
Cytotoxic activated macrophages (CM) inhibited the growth of neoplastic L1210 cells in vitro but L1210 cell death was minimal to nonexistent. L1210 cells injured by CM were separated from macrophages and studied in an isolated system. CM-injured L1210 cells had an absolute requirement for glucose or another glycolyzable hexose (mannose or fructose) for at least 40 h after removal from macrophages. If the culture medium lacked sufficient concentration of one of these sugars, CM-injured L1210 cells died within 4 h. Uninjured L1210 cells cultured alone or with peptone-stimulated macrophages had no such requirement and maintained complete viability in hexoseless medium. The hexose requirement of CM-injured L1210 cells could not be fulfilled by other naturally occurring monosaccharides, glucose or mannose derivatives, or substrates that can be oxidized by mitochondria. The concentration requirements for glucose, mannose, and fructose by CM-injured L1210 cells correlated with the concentrations required to support maximal glycolysis of these sugars by other murine ascites cells. A concentration of 2-deoxy-D-glucose which completely inhibited L1210 cell glycolysis also complete prevented the ability of glucose or mannose to maintain viability of CM-injured L1210 cells. Interaction with CM led to inhibition of L1210 cell mitochondrial oxidative phosphorylation. This was supported by the findings that: (a) CM-injured L1210 cells had no Pasteur effect; their rate of aerobic glycolysis was the same as the rate of anaerobic glycolysis of uninjured L1210 cells, (b) Endogenous respiration of CM-injured L1210 cells was 15% of normal. Maximal inhibition of uninjured L1210 cell respiration by a specific mitochondrial poison (oligomycin) was nearly the same (13% of normal). It followed that CM-injured L1210 cells required hexose for chemical energy production via the glycolytic pathway. CM-induced mitochondrial injury occurred in five other neoplastic cell lines tested.
Animals↗
Immunotherapy with nonviable microbial components.
Structural components of microorganisms have been studied for immunopotentiating effect with the aid of transplantable (line 10) tumors in syngeneic guinea pigs. Microbial components were associated with oil droplets, suspended in Tween-saline, and injected intralesionally. BCG cell walls, given in this way, produced regression and cure of 50-60% of established tumors, as did viable BCG. Lipid extraction markedly reduced the tumor-regressing potency of cell walls, but P3, a trehalose mycolate present in the extract, restored full activity to the cell wall residue. P3 alone was nonsensitizing and had no antitumor activity, but it enhanced the latter property of various other microbial products. For example, the cure rates produced by cell walls of M. tuberculosis, M. bovis, M. phlei, or M. smegmatis were enhanced from 20-60% to as much as 90% by addition of P3. P3 also conferred antitumor activity on products from unrelated microbes, such as cell walls of E. coli, and in combination with endotoxins from rough Re mutant salmonellae, it produced cure rates of up to 93%. These results suggest that P3 is essential to the immunopotentiating activity of mycobacteria and that it may be broadly applicable in immunotherapy of cancer with microbial agents.
Animals↗
Cutaneous granulomatous response to BCG cell walls with reference to cancer immunotherapy.
A chronic inflammatory response produced by cell walls of Mycobacterium bovis strain BCG associated with microscopic oil droplets (BCG CW-O) was studied with reference to the tumor-regressing ability of this preparation. When BCG CW-O was injected intradermally in the footpads of guinea pigs, intense inflammation developed at the site of injection and in the draining popliteal lymph node. This was characterized histologically as granulomatous inflammation. The intensity of the response was related to the dose of BCG CW-O. Cell walls without oil produced the same type of inflammation but much less in degree. Data are presented that demonstrate the immunological nature of this response and classify it as a cell-mediated immune reaction. Ramifications of this chronic inflammatory reaction occurring at the site of a tumor are discussed.
Animals↗
Delayed hypersensitivity and granulomatous response after immunization with protein antigens associated with a mycobacterial glycolipid and oil droplets.
A myocardial glycolipid (P3) mixed with protein antigens in oil-in-water emulsion induced lasting delayed hypersensitivity (DH) and granulomatous inflammation after intradermal injection into guinea pigs. This did not occur when P3 and bovine serum albumin (BSA) were given in Freund's incomplete adjuvant. The oil-in-water emulsions consisted of microscopic oil droplets suspended in aqueous medium. By separating oil and aqueous phases from BSA + P3 emulsion it was shown that antigen retained with oil droplets led to DH and granuloma formation. The association of antigen with oil droplets was P3 dependent and was quantitated with 125I-labeled BSA. The same phenomenon occurred with 125I-labeled rabbit gamma-globulin (RGG) + P3 emulsion. Fluorescein-conjugated RGG was observed in a particulate state within or on oil droplets in emulsion containing P3. These physical characteristics of antigen + P3 emulsion appeared to be important for immunogenicity.
Animals↗
Tumor regression caused by endotoxins and mycobacterial fractions.
A transplantable hepatocarcinoma of guinea pigs was used as an experimental model for immunotherapy of cancer. Earlier work showed that complete regression of 6- to 7-day-old tumors could be obtained in about 60% of cases by inoculation of the tumors with live BCG or certain fractions of BCG attached to minute oil droplets and suspended in Tween-saline. One of the most essential fractions was P3, a nonsensitizing, nonantigenic trehalose mycolate related to, but not identical with, cord factor. We now report that oil-droplet preparations containing P3 and bacterial endotoxin (ET) produced cure rates of up to 90% in the same system. In addition, regression was faster than with BCG, and older tumors could be treated successfully. The most effective ET's were from rough strains of salmonellae, known as Re mutants, which could not synthesize and attach the polysaccharide portion of endotoxin.
Animals↗
Migration inhibitory factor and type II interferon in the circulation of mice sensitized with mycobacterial components.
Migration inhibitory factor (MIF) and type II interferon were released into the circulation after mice had been sensitized i.v. with a bacillus of Calmette and Guerin (BCG) cell-wall-in-oil vaccine and then challenged four weeks later with 50 mg old tuberculin. At least two components of BCG, protein (PPD) and lipid (P-3), have been identified which are essential for the type of sensitization in which mediators are released after appropriate challenge. The route of sensitization had a marked effect on the development of delayed footpad reactions, release of lymphokines, and resistance to infection with virulent tubercle bacilli. Sensitization by the subcutaneous route tended to induce more pronounced delayed footpad reactions, whereas the i.v. route of sensitization was associated with maximum release of mediators. A close correlation existed between the conditions of sensitization that resulted in maximum production of lymphokines (MIF and Type II interferon) and those that caused protection against aerosol challenge with a virulent strain of Mycobacterium tuberculosis.
Animals↗