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R P Daniele

Publications and source records attributed to R P Daniele.

At least 19 recordsLinked to original sources
PubMed1994

Role of microtubules in random cell migration: stabilization of cell polarity.

The role of microtubules in random cell migration was investigated using time-lapse videomicroscopy to record in vitro the shape and motile behavior of guinea pig alveolar macrophages before and after disrupting microtubules with colcemid. Cell migration was quantified in terms of directional persistence time and speed. Motility was also correlated with morphological polarity: cells having a single lamellipodal region (monopolar cells) migrated, whereas those lacking a lamellipod (apolar cells) or with opposing lamellipodal regions (bipolar cells) did not migrate. Within 2 hours, colcemid caused a shift in polarity from 80% monopolar cells to 40% monopolar and 40% bipolar cells and a corresponding decrease from 80% to 40% in the fraction of migrating cells. Mean persistence time and speed decreased only slightly (approximately 20%) for those cells (still monopolar) which continued to migrate in the presence of colcemid. Persistence time and speed actually increased for many individual cells, indicating that random migration did not require intact microtubules. We conclude that colcemid treatment destabilizes monopolarity, leading to the gradual loss of monopolarity and consequent inhibition of migration. While a cell remains monopolar, it will continue to migrate even in the absence of intact microtubules, but microtubules are required for the long-term maintenance of cellular monopolarity and, thus, for continued motility.

Animals↗
PubMed1990

Quantitative relationships between single-cell and cell-population model parameters for chemosensory migration responses of alveolar macrophages to C5a.

Phenomenological parameters from a mathematical model of cell motility are used to quantitatively characterize chemosensory migration responses of rat alveolar macrophages migrating to C5a in the linear under-agarose assay, simultaneously at the levels of both single cells and cell populations. This model provides theoretical relationships between single-cell and cell-population motility parameters. Our experiments offer a critical test of these theoretical linking relationships, by comparison of results obtained at the cell population level to results obtained at the single-cell level. Random motility of a cell population is characterized by the random motility coefficient, mu (analogous to a particle diffusion coefficient), whereas single-cell random motility is described by cell speed, s, and persistence time, P (related to the period of time that a cell moves in one direction before changing direction). Population chemotaxis is quantified by the chemotactic sensitivity, chi 0, which provides a measure of the minimum attractant gradient necessary to elicit a specified chemotactic response. Single-cell chemotaxis is characterized by the chemotactic index, CI, which ranges from 0 for purely random motility to 1 for perfectly directed motility. Measurements of cell number versus migration distance were analyzed in conjunction with the phenomenological model to determine the population parameters while paths of individual cells in the same experiment were analyzed in order to determine the single-cell parameters. The parameter mu shows a biphasic dependence on C5a concentration with a maximum of 1.9 x 10(-8) cm2/sec at 10(-11) M C5a and relative minima of 0.86 x 10(-8) cm2/sec at 10(-7) M C5a and 1.1 x 10(-8) cm2/sec in the absence of Ca; s and P remain fairly constant with C5a concentration, with s ranging from 2.1 to 2.5 microns/min and P varying from 22 to 32 min. chi 0 is equal to 1.0 x 10(-6) cm/receptor for all C5a concentrations tested, corresponding to 60% correct orientation for a difference of 500 bound C5a receptors across a 20 microns cell length. The maximum CI measured was 0.2. Values for the population parameters mu and chi 0 were calculated from single-cell parameter values using the aforementioned theoretical linking relationships. The values of mu and chi 0 calculated from single-cell parameters agreed with values of mu and chi 0 determined independently from population migrations, over the full range of C5a concentrations, confirming the validity of the linking equations. Experimental confirmation of such relationships between single-cell and cell-population parameters has not previously been reported.

Animals↗
PubMed1990

Clinical role of bronchoalveolar lavage in adults with pulmonary disease.

BAL remains a powerful investigative tool. In a short span of 20 yr, it has helped tremendously in understanding some of the aspects of the pathogenesis of diseases involving the lower respiratory tract. To realize its full potential in the diagnosis and management of diseases involving the lower respiratory tract, there is a great need for standardization of the technical aspects of BAL as well as processing and analysis of the BAL cellular- and fluid-phase components. Despite these hurdles, BAL has been found to be diagnostic in several infectious and noninfectious diseases involving the lower respiratory tract, and it provides valuable information that may be helpful in characterizing the prognosis and response to therapy in certain interstitial diseases of the lung. It is expected that with future research, in particular long-term prospective epidemiologic and clinical studies in pneumoconioses and in other interstitial lung disease, BAL will prove more valuable in the diagnosis and management of such disease.

Bronchoalveolar Lavage Fluid↗
PubMed1989

The motile response of alveolar macrophages. An experimental study using single-cell and cell population approaches.

In this report, we studied the applicability of a random walk model of individual cell motility in predicting the motile behavior of alveolar macrophage populations under agarose. The migration of a population of cells in the absence of a chemotactic or chemokinetic gradient can be characterized by the random motility coefficient, mu, which is analogous to a particle diffusion coefficient. Random walk theory relates this latter coefficient to particle speed and collision time (equivalent to the time between changes in particle direction). By analogy, according to a similar random walk theory for cell migration, mu for a cell population is a function of the speed and persistence time (with direction changes governed by cell behavioral processes rather than by collisions) of individual cells. To test the model, normal guinea pig alveolar macrophages were incubated in the presence or absence of uniform concentrations of the chemotactic tripeptide formyl-norleucyl leucyl phenylalanine (FNLLP) to elicit different levels of motile activity. Mu was calculated from cell population density profiles obtained by fixing and staining cultures after 2, 3, or 4 days. In parallel experiments, individual cell speeds and persistence times were measured from 1-h, time-lapse video microscopy recordings. The value of mu calculated from single-cell measurements was in good agreement with that from population studies for stimulated random migration (at 10(-7) to 10(-11) M FNLLP), but not in the absence of stimulant. Overall, these results support the applicability of the random walk model of individual cell migration to randomly migrating alveolar macrophage populations.

Animals↗
PubMed1988

The effect of alveolar macrophage chemotaxis on bacterial clearance from the lung surface.

In the distal airways, the alveolar macrophage plays a crucial role in defense of the lung against inhaled pathogens. These cells have been observed in vitro to move chemotactically in response to many types of attractants that may be present on the lung's surface during a bacterial or particulate challenge. This study investigated the hypothesis that chemotactic ability is an important part of the defensive action of these cells as they ingest bacteria on the lung surface. We compared our mathematical model for lung clearance to previously published bacterial clearance data and determined the amount of alveolar macrophage chemotactic ability required to account for observed clearance rates. The results showed that random motion is insufficient for clearance, and a moderate amount of chemotactic ability is necessary for our predicted clearance rates to agree with experimentally measured clearance rates.

Aerosols↗
PubMed1988

Interleukin-1-beta gene expression in human monocytes and alveolar macrophages from normal subjects and patients with sarcoidosis.

To assess the ability of human alveolar macrophages to produce interleukin-1-beta (IL1-beta), we examined IL1-beta mRNA accumulation in autologous monocytes and alveolar macrophages from normal volunteers. Escherichia coli lipopolysaccharide stimulation of monocytes induced rapid IL1-beta mRNA accumulation, reaching a maximum at 2 to 4 h and declining thereafter. Alveolar macrophages, however, accumulated much less mRNA than did monocytes. This difference could not be explained by differences in kinetics of IL1-beta gene expression between the 2 cell types, isolation techniques, or alveolar macrophage lidocaine exposure. This suggests that differences in transcription of the IL1-beta gene exist between these 2 cell types. Aging is a possible factor important in some functional differences between these 2 cell types. To determine if this difference in the capacity to express the IL1-beta gene might be a function of cell maturity, monocytes were aged in vitro for 7 days. After this culture period, monocytes had a marked decrease in the ability to accumulate IL1-beta mRNA, suggesting that cell aging may be one mechanism involved in producing these transcriptional differences. Because IL1-beta has also been implicated in the inflammatory and fibrotic responses in pulmonary sarcoidosis, 4 patients with newly diagnosed sarcoidosis underwent bronchoalveolar lavage, and IL1-beta mRNA accumulation was compared in their alveolar macrophages and blood monocytes. Comparing normal alveolar macrophages to those from patients with sarcoidosis showed no differences in the kinetics of IL1-beta mRNA expression or in the LPS-induced levels of IL1-beta mRNA accumulation. In addition, augmented levels of IL1-beta transcript were not noted in unstimulated sarcoid alveolar macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Northern↗
PubMed1988

Dexamethasone inhibition of interleukin 1 beta production by human monocytes. Posttranscriptional mechanisms.

Dexamethasone is known to have an inhibitory effect on IL-1 production. To determine the mechanism(s) of this inhibition, adherent human blood monocytes were stimulated with Escherichia coli lipopolysaccharide (LPS) (10 micrograms/ml) in the presence of dexamethasone. Nuclear transcription run-off assays showed that LPS induced IL-1 beta gene transcription two- to fourfold and that this induction was unaffected by dexamethasone exposure (10(-5) M). The lack of dexamethasone's transcriptional effects was further supported by the absence of any significant change in IL-1 beta mRNA accumulation between LPS-stimulated monocytes exposed or unexposed to dexamethasone, as determined by Northern blot analysis. Posttranscriptionally, dexamethasone was found to have multiple effects: slight prolongation of IL-1 beta mRNA half-life, moderate inhibition of translation of the IL-1 beta precursor, and profound inhibition of the release of IL-1 beta into the extracellular fluid. The data indicate that IL-1 beta is first translated as the 33,000-D pro-IL-1 beta protein, the predominant intracellular form, and the processed to a 17,500-D IL-1 beta protein before or during extracellular transport. The major inhibitory effects of dexamethasone appear to be directed at the translational and posttranslational steps involved in these events.

Dexamethasone↗
PubMed1988

Proliferative response of bronchoalveolar lymphocytes to beryllium. A test for chronic beryllium disease.

STUDY OBJECTIVE: to ascertain whether measuring the proliferative response of bronchoalveolar lymphocytes to beryllium salts is useful for diagnosing chronic beryllium disease. DESIGN: prospective case series compared to normal volunteers and patients with sarcoidosis. SETTING: university referral center. PATIENTS: twenty-three consecutive beryllium workers were evaluated. Fourteen had chronic beryllium disease diagnosed on the basis of histologic evidence of a progressive pulmonary granulomatosis. Four had biopsy evidence of non-beryllium disease. Three had probable chronic beryllium disease but did not have lung biopsies. Two did not have biopsies and had basilar fibrosis on chest roentgenogram suggestive of non-beryllium lung disease. These patients were compared with 6 normal volunteers and 16 patients with sarcoidosis. MEASUREMENTS AND MAIN RESULTS: bronchoalveolar lavage was done and the proliferative response of the lung cells to two beryllium salts was tested. A positive proliferative test was defined as a stimulation index of more than five on two determinations. The sensitivity of this test was 100% in the 14 patients with definite chronic beryllium disease. The specificity of the test was also 100% among the normal volunteers and the 16 patients with sarcoidosis. The test was positive in none of the four patients with biopsy evidence of non-beryllium disease, none out of two patients with lower lobe fibrosis suggestive of non-beryllium disease, and all of three patients with probable chronic beryllium lung disease. CONCLUSIONS: the proliferative response of bronchoalveolar lymphocytes to beryllium appears to be a useful test for chronic beryllium disease.

Berylliosis↗
PubMed1987

Differential prostaglandin production by unfractionated and density-fractionated human monocytes and alveolar macrophages.

Mononuclear phagocyte elaboration of E series prostaglandins (PGE) may be important in the regulation of inflammatory and fibrotic reactions. Mononuclear phagocytes are morphologically and functionally heterogeneous cells. To further understand the processes controlling inflammation and fibrosis, in particular that in the human lung, we characterized the ability of unfractionated and density-fractionated human alveolar macrophages and blood monocytes to elaborate PGE. Alveolar macrophages and blood monocytes constitutively elaborated small amounts of PGE, and their elaboration of PGE was increased with lipopolysaccharide (LPS) stimulation. Monocytes elaborated more PGE than autologous alveolar macrophages. In addition, denser monocytes (specific gravity greater than 1.055) and denser alveolar macrophages (specific gravity greater than 1.044) elaborated more PGE than less dense monocytes and alveolar macrophages, respectively. When monocytes were incubated in vitro, their constitutive PGE elaboration decreased with time. However, in vitro incubation did not cause monocytes to lose their capacity to elaborate PGE in response to LPS. Thus, mononuclear phagocyte populations differ in their ability to elaborate PGE. These differences can be only partially attributed to differences in cell maturation.

Cell Fractionation↗
PubMed1987

Chronic beryllium disease in a precious metal refinery. Clinical epidemiologic and immunologic evidence for continuing risk from exposure to low level beryllium fume.

Five workers at a precious metal refinery developed granulomatous lung disease between 1972 and 1985. The original diagnosis was sarcoidosis, but 4 of the workers were subsequently proved to have hypersensitivity to beryllium by in vitro proliferative responses of lymphocytes obtained by bronchoalveolar lavage. Review of medical records of coworkers and extensive industrial hygiene surveillance of the plant demonstrated that 4 cases occurred in the furnace area where air concentrations of beryllium fume were consistently below the permissible exposure limit of 2 micrograms/M3. A single case has been recognized from parts of the refinery where exposures to cold beryllium dust often exceeded the standard by as much as 20-fold. These data demonstrate that chronic beryllium disease still occurs and confirm the importance of specific immunologic testing in patients suspected of having sarcoidosis but with potential exposure to beryllium. The data raise concern about the adequacy of modern industrial controls, especially in the setting of exposure to highly respirable beryllium fume.

Adult↗
PubMed1987

Alveolar macrophages, blood monocytes, and density-fractionated alveolar macrophages differ in their ability to promote lymphocyte proliferation to mitogen and antigen.

We compared the relative abilities of alveolar macrophages (AM), blood monocytes (BM), and density-fractionated AM to support antigen- and mitogen-induced proliferation of autologous T cells in normal volunteers. The AM were able to promote the T-cell proliferative response to antigen, but they did so less effectively than did the BM. Density-fractionated AM were heterogeneous in their ability to support T-cell responses. More proliferation occurred with the densest AM than with the least dense AM. In contrast to antigen-induced responses, mitogen-induced responses were supported more effectively by AM and density-fractionated AM than by BM. The ability of AM, density-fractionated AM, and BM to support T-cell responses did not correlate with surface expression of class II major histocompatibility determinants. Addition of purified IL-1 resulted in a partial restoration of T-cell proliferation when low-density AM were used but no augmentation when unfractionated AM were used. This suggests that reduced IL-1 activity may partially explain the decreased ability of low density AM to promote T-cell responses, but that other processes may also contribute to differences in accessory cell function among AM, BM, and density-fractionated AM.

Antigens↗
PubMed1987

Carbohydrate differences in HLA-DR molecules synthesized by alveolar macrophages and blood monocytes.

Two-dimensional gel electrophoresis was used to compare immunoprecipitated, radiolabeled HLA-DR molecules synthesized by alveolar macrophages (AM) and blood monocytes (BM) of the same healthy, nonsmoking volunteers. No charge differences were noted by isoelectric focusing. Molecular weight analysis of HLA-DR from AM revealed a complex pattern of radioactive spots differing slightly in molecular weight. This pattern was apparent in both the alpha and the beta chains. In contrast, a simpler pattern without the slight molecular weight differences was noted in HLA-DR from BM. The differences were eliminated by labeling AM and BM in the presence of tunicamycin, a specific inhibitor of protein-carbohydrate linkages of the N-glycosidic type. Thus, it appears that neutral, N-linked carbohydrate moieties account for the differences in HLA-DR molecules between AM and BM. The differential glycosylation of HLA-DR molecules in AM and BM may relate to mononuclear phagocyte development as well as antigen-presenting function.

Carbohydrate Metabolism↗
PubMed1986

The role of the accessory cell in mitogen-stimulated human T cell gene expression.

The role of the accessory cell in optimizing T cell proliferative responses to mitogens is a well known but poorly understood phenomenon. To further dissect the function of the accessory cell in allowing T cell proliferation, we compared mitogen-induced c-myc, interleukin 2 (IL 2), and IL 2 receptor gene expression in peripheral blood mononuclear cells (PBMC) and in T cells rigorously depleted of accessory cells through differential adherence and anti-Dr (anti-class II major histocompatibility antigen) monoclonal antibody complement-directed cytotoxicity. In cultures stimulated with phytohemagglutinin (PHA), a mitogen that requires accessory cells to induce T cell proliferation, expression of all measured genes was accessory cell dependent, since accumulation of their mRNA in PBMC was greater than that in cultures depleted of accessory cells. These genes varied in their accessory cell dependence, with IL 2 expression most dependent, c-myc expression least dependent, and IL 2 receptor expression intermediate in dependency. Use of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or ionomycin, mitogens that stimulate T cell proliferation independent of accessory cells, induced equal levels of gene expression in PBMC and in T cells depleted of accessory cells. These results suggest that PHA-stimulated T cells are dependent on an accessory cell signal(s) for optimal expression of the genes for c-myc, IL 2, and IL 2 receptor, and for proliferation. In addition, this signal(s) appears to be delivered early in the course of T cell activation events, since it can be bypassed by mitogens that directly activate protein kinase C (TPA) or induce calcium translocation (ionomycin). In addition, these data provide further evidence that expression of the c-myc protooncogene is insufficient for T cell mitogenesis, since PHA-induced accumulation of c-myc mRNA was only partially accessory cell dependent, whereas proliferation was completely accessory-cell dependent.

Antigen-Presenting Cells↗