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J R Hoidal

Publications and source records attributed to J R Hoidal.

140 records · Page 8Linked to original sources
PubMed1980

Phagocytosis by human alveolar macrophages and neutrophils: qualitative differences in the opsonic requirements for uptake of Staphylococcus aureus and Streptococcus pneumoniae in vitro.

The opsonic requirements for uptake of 3H-adenine-labeled Staphylococcus aureus (strains 502A, Wood 46, or 209) or Streptococcus pneumoniae (Type VII) by human alveolar macrophages (AM) or neutrophils (PMN) were evaluated and compared using a quantitative assay of phagocytosis. AM readily engulfed S. aureus organisms preopsonized with 1% albumin, serum, or serum that had been heated (56 degrees C for 30 min) to inactivate complement, whereas uptake of S. aureus by PMN occurred only after preopsonization with unheated, complement replete serum (2.5%). In contrast, uptake of S. pneumoniae organisms by AM or PMN did not occur with only albumin preopsonization, but required high concentrations (more than 40%) of unheated serum. The results indicate that there are qualitative and quantitative differences in the requirements for optimal ingestion of bacteria by human AM or PMN that relate not only to the type of organism but also to the type of phagocyte. Variations in opsonic requirements may be a key factor in the different cellular responses and clearances of inhaled S. aureus or S. pneumoniae organisms by the lungs.

Adenine↗
PubMed1979

Production of hydroxyl radical by human alveolar macrophages.

Stimulated human alveolar macrophages were demonstrated to oxidize B-methyl proprionaldehyde (methional) or 2-keto-4-thiomethylbutyric acid to ethylene (C2H4). Agents which are believed to scavenge the hydroxyl radical (.OH), sodium benzoate, and mannitol, as well as scavengers of superoxide anion (O2-) or hydrogen peroxide, decreased C2H4 production, implicaing .OH as the oxidizing radical. Differences in C2H4 rpoduction, as well as oxygen uptake and O2- release between human alveolar macrophages and polymorphonuclear leukocytes, were also documented.

Aldehydes↗
PubMed1979

Defective oxidative metabolic responses in vitro of alveolar macrophages in chronic granulomatous disease.

After stimulation with bacteria, alveolar macrophages (AM) from uninfected normal subjects or persons with pneumonia approximately doubled their rates of O2 consumption, superoxide anion generation, and glucose (1(-14)C) oxidation. In contrast, bacteria-stimulated AM from a patient with chronic granulomatous disease (CGD) failed to consume more O2, make superoxide anion, or oxidize glucose. In addition, AM from the patient with CGD did not respond to stimulation by a chemical agent, phorbol myristate acetate, which increased the metabolic activities of AM from control subjects. The appearance, esterase and Gomori acid phosphatase staining, phagocytic ability, unstimulated O2 consumption, and response to methylene blue of AM from the CGD patient were normal. The results extend the biochemical defect in patients with CGD beyond abnormalities in their circulating neutrophils and monocytes, to their tissue-associated lung macrophages. The results also indicate that AM from patients with CGD may have an additional abnormality in metabolism, which is a lack of enhanced mitochondrial respiration during phagocytosis. The studies also document the selective action of phorbol myristate acetate, which stimulated the metabolic activities of normal AM, but not of those from the patient with CGD.

Adolescent↗
PubMed1979

Generation of hydroxyl radical by enzymes, chemicals, and human phagocytes in vitro. Detection with the anti-inflammatory agent, dimethyl sulfoxide.

Methane (CH(4)) production from the anti-inflammatory agent, dimethyl sulfoxide (DMSO), was used to measure .OH from chemical reactions or human phagocytes. Reactions producing .OH (xanthine/xanthine oxidase or Fe(++)/EDTA/H(2)O(2)) generated CH(4) from DMSO, whereas reactions yielding primarily O-(2) or H(2)O(2) failed to produce CH(4). Neutrophils (PMN), monocytes, and alveolar macrophages also produced CH(4) from DMSO. Mass spectroscopy using d(6)-DMSO showed formation of d(3)-CH(4) indicating that CH(4) was derived from DMSO. Methane generation by normal but not chronic granulomatous disease or heat-killed phagocytes increased after stimulation with opsonized zymosan particles or the chemical, phorbol myristate acetate. Methane production from DMSO increased as the number of stimulated PMN was increased and the kinetics of CH(4) production approximated other metabolic activities of stimulated PMN. Methane production from stimulated phagocytes and DMSO was markedly decreased by purportedly potent .OH scavengers (thiourea or tryptophane) and diminished to lesser degrees by weaker .OH scavengers (mannitol, ethanol, or sodium benzoate). Superoxide dismutase or catalase also decreased CH(4) production but urea, albumin, inactivated superoxide dismutase, or boiled catalase had no appreciable effect. The results suggest that the production of CH(4) from DMSO may reflect release of .OH from both chemical systems and phagocytic cells. Interaction of the nontoxic, highly permeable DMSO with .OH may explain the anti-inflammatory actions of DMSO and provide a useful measurement of .OH in vitro and in vivo.

Cells, Cultured↗
PubMed1979

Influence of cationic local anesthetics on the metabolism and ultrastructure of human alveolar macrophages.

The concentrations of cationic local anesthetics present in effluents from subsegmental bronchoscopic lavage were determined. Subsequently, the effect of these agents on lavaged human AM was evaluated in vitro. The results indicate that concentrations of LDC that may alter human AM function are present in effluents during routine subsegmental bronchopulmonary lavage. LDC and TRC in a dose-dependent fashion rapidly inhibited oxygen consumption and superoxide anion (O-2.) release by unstimulated human AM or AM stimulated by bacteria or the membrane-active chemical PMA. Concentrations of 2 mM TRC or 16 mM LDC reduced O2 consumption and O-2. release by unstimulated AM by more than 70% and blocked the usual spurt in O2 uptake and O-2. release observed for stimulated AM. This inhibition was not due to cytotoxicity, since washing n a balanced salt solution restored the metabolic function of treated AM. TRC or LDC also had effects on the morphology of washed human AM, causing rounding of the cell surface (scanning electron microscopy). In summary, the findings show that anesthetic agents routinely present in lavage effluents have the capacity to alter the function and structure of human AM. Although the effect must be considered in the design and interpretation of studies using AM obtained by bronchopulmonary lavage, the cationic anesthetics may also prove to be valuable agents for evaluating cell membrane-related events of human AM.

Anesthetics, Local↗
PubMed1978

Reversible impairment of the adherence of alveolar macrophages from cigarette smokers.

The nylon fiber adherence in vitro of alveolar macrophages (AM) from cigarette smokers was uniformly decreased. The mean adherence of AM from 16 cigarette smokers was 53 +/- 3.0 per cent, compared to a mean adherence of 77.2 +/- 1.7 per cent for AM from control nonsmokers. The defect was not present after the subjects quit smoking, was not a result of factors in lavage fluids from smokers, and was not apparent in polymorphonuclear leukocytes. The morphologic features of the surface of AM were examined with scanning electron microscopy to determine whether morphologic changes paralleled the decreased adherence of AM from smokers. Marked alterations in the surface of AM from cigarette smokers, which could affect the ability of AM to adhere optimally, were demonstrated before attachment to the fiber. In summary, there exists a reversible, intrinsic defect in the structure and adherence of AM from cigarette smokers that may influence their function and may accout, in part, for the increased yield of AM from the lavage fluid of cigarette smokers.

Cell Adhesion↗
PubMed1978

The effect of phorbol myristate acetate on the metabolism and ultrastructure of human alveolar macrophages.

In the present investigation we examined the influence of the surface-active agent phorbol myristate acetate (PMA) and opsonized heat-killed bacteria (HKB) on oxygen consumption, superoxide release, and glucose oxidation of human alveolar macrophages (AM). Both PMA and HKB produced a surge in oxygen consumption, superoxide release, and oxidation of 1-14C-glucose and 6-14C-glucose by human AM. Examination of AM by electron microscopy following stimulation by these two agents demonstrated membrane ruffling, loss of microvilli, and increased vacuolization in PMA-treated cells and phagocytic vacuoles containing bacteria in HKB-treated cells. The vacuolization produced by PMA-treated AM was much less striking than the vacuolization produced in PMA-treated leukocytes. The similarity in the metabolic and some of the physical responses of AM stimulated by PMA and HKB suggest that PMA may be a useful agent for evaluating cell-membrane-related events of phagocytosis in AM.

Cell Membrane↗
PubMed1978

Comparison of the metabolism of alveolar macrophages from humans, rats, and rabbits: phorbol myristate acetate.

Metabolic activities of unstimulated or stimulated AMs from humans, rats, and rabbits were examined and compared in vitro. Rates of oxygen consumption, chemiluminescence, and glucose (1- or 6-14C) oxidation by unstimulated AMs from these three species increased following stimulation of the AMs by bacteria or PMA. Although the absolute metabolic responses of AMs from humans, rats, or wild rabbits were different, the metabolic activities from each species were nearly identical when compared on the basis of protein content of the cells. In contrast to the enhanced biochemical responses of AMs from humans, rats, or wild rabbits, stimulated AMs from certain commercially supplied rabbits failed to increase their metabolism. The failure of AMs from these rabbits to respond metabolically was probably due to an acquired abnormality resulting from their care and storage at the supplier. The defect was associated with the presence of large numbers of Bordetella bronchiseptica organisms in the lavage effluents from these commercially supplied rabbits. This abnormality in metabolism of AMs was reversed following prolonged residence of the rabbits in the laboratory, and the correction of the defect was accompanied by a disappearance of B. bronchiseptica from the lavage fluid. The results comprehensively compare and contrast the metabolism of AMs from humans and animals and emphasize the need to document the appropriateness of animal models before using them to predict biologic reactions of humans.

Animals↗
PubMed1978

Production of C2 by human alveolar macrophages.

Human and rat alveolar macrophages produce haemolytic C2 during in vitro culture. We conclude that C2 synthetic ability is maintained during in vivo maturation of human monocytes to macrophages and that production of complement components by mature tissue macrophages may be important for optimal generation of inflammatory responses.

Animals↗
PubMed1977

Chemiluminescence by human alveolar macrophages: stimulation with heat-killed bacteria or phorobol myristate acetate.

Chemiluminescence of human alveolar macrophages (AM) was evaluated in vitro. Unstimulated AM generated chemiluminescence that remained constant during incubation. Addition of heat-killed Staphylococcus aureus 502A (HKB) or a chemical agent, phorbol myristate acetate, produced high rates of chemiluminescence that were significantly (P less than 0.05) increased over unstimulated AM. Phorbol myristate acetate-and HKB-stimulated increases in AM chemiluminescence were completely blocked by the enzyme superoxide dismutase. In comparison with unstimulated polymorphonuclear leukocytes, unstimulated AM had significantly (P less than 0.005) greater levels of chemiluminescence. However, after stimulation by phorbol myristate acetate or HKB, AM showed less chemiluminescence than similarly treated polymorphonuclear leukocytes.

Humans↗