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Biomedical subjects

J Dolovich

Publications and source records attributed to J Dolovich.

At least 91 records · Page 5Linked to original sources
PubMed1991

Immunologic characterization of a recombinant Kentucky bluegrass (Poa pratensis) allergenic peptide.

A recombinant peptide of Kentucky bluegrass (KBG) pollen was synthesized as a fusion protein (FP) in Escherichia coli by recombinant DNA procedures and was compared with its natural counterparts with respect to its allergenic properties. The FP was demonstrated to bind to the IgE antibodies (Abs) of greater than or equal to 95% of 55 individual sera examined. A positive correlation (r = 0.90) was observed between the levels of IgE Abs corresponding to the FP and the grass-pollen extract(s). With sera of five allergic patients, the IgE binding of three different protein preparations were compared, namely, KBG pollen proteins, 27 to 35 kd gel-purified pollen proteins, and the FP. Results indicated that about 50% of the total IgE binding of KBG pollen proteins was due to the IgE Abs specific to FP. Comparison of the above protein preparations with respect to their abilities to specifically stimulate murine popliteal lymph node cells in vitro indicated that the total pollen proteins stimulated the highest proliferation of lymph node cells. Interestingly, the FP supported higher proliferation of lymph node cells than the gel-purified proteins. Collectively, these results suggest that the recombinant peptide constitutes a major allergenic constituent of grass pollens and may be of diagnostic and therapeutic value.

Allergens↗
PubMed1991

Antibodies to toluene diisocyanate in patients with and without dialysis anaphylaxis.

In a majority of patients with anaphylaxis to dialysis, ethylene oxide has been identified as an etiologic agent. In a significant minority of patients sustaining such reactions, the antigen remains unidentified. Conflicting results have been published with regard to isocyanates as a possible antigen. The authors studied 19 hemodialysis patients with anaphylaxis in whom IgE against ethylene oxide-human serum albumin (ETO-HSA) was not identified (Group 1) and 25 peritoneal dialysis patients without anaphylaxis (Group 2). IgE against toluene diisocyanate-human serum albumin (TDI-HSA) was found in one patient in Group 1, and a similar incidence of IgG against TDI-HSA in Group 1 (16%) and Group 2 (12%) was noted. The results do not suggest that IgE against TDI-HSA is an important cause of dialysis anaphylaxis.

Anaphylaxis↗
PubMed1991

Structural cell-derived cytokines in allergic inflammation.

Based on observations of fluctuations in progenitors for inflammatory cells during allergic responses, we have proposed that a primary determinant of allergic inflammation involves microenvironmental influences on hemopoietic cell differentiation and phenotype; in addition, as a corollary of this, inflammatory cell burden is proposed as an important indicator of the severity and pattern of the inflammatory process in allergy. The studies outlined here focus on the effects of epithelial-cell- and fibroblast-derived cytokines on granulocytic and monocytic cell differentiation and activation in models involving allergic reactions in the upper and lower airways. Pure cultures of nasal or bronchial epithelial cells or fibroblasts are observed to give rise to cytokines important in inducing the differentiation of basophils, eosinophils, neutrophils and monocyte/macrophages. Gene expression, production and secretion of granulocyte/macrophage-colony-stimulating factor, interleukin-6 (IL-6) and IL-8 can be demonstrated in vitro and in vivo. Up-regulation of gene expression and production of these cytokines, which are important in inducing basophil, eosinophil and neutrophil/macrophage differentiation in several assays, is seen with IL-1 and the neuropeptide substance P; conversely, inhibition of cytokine production by structural cells is observed after pretreatment with corticosteroids in vitro, paralleling in vivo effects. Other modulatory effects also examined include: antiallergic compounds, which may affect posttranscriptional events in cytokine production, and heavy metal ions, which can also induce changes in gene expression. Structural-cell-derived extracellular matrices appear also to be important both in mast cell differentiation and in macrophage cytokine gene expression, both of which potentially feedback upon chronic allergic inflammatory processes, leading to their perpetuation.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchi↗
PubMed1991

Human upper airway epithelial cell-derived granulocyte-macrophage colony-stimulating factor induces histamine-containing cell differentiation of human progenitor cells.

Nasal polyps and allergic rhinitis are upper airway inflammatory conditions characterized by increased numbers of eosinophils and metachromatic cells in the epithelial layer of the nasal mucosa. The objective of the current studies was to investigate the potential contribution of epithelial cells to the accumulation of inflammatory cells in the tissue. We have established pure cultures of human upper airway epithelial cells from normal and inflamed nasal polyps and allergic rhinitis tissue and examined the ability of conditioned medium from these cells (EpCM) to induce differentiation of human hemopoietic progenitors in vitro. We show that, under appropriate culture conditions, EpCMs, particularly those from cells derived from inflamed tissues, induce histamine-containing cell differentiation of cells of the human HL-60 myeloid leukemia cell line. These EpCMs also induce the emergence of both eosinophil/basophil and granulocyte/macrophage colonies in methylcellulose cultures of human peripheral blood mononuclear cells. We also show that CMs from epithelial cells derived from inflamed tissues contain greater amounts of granulocyte-macrophage colony-stimulating factor (GM-CSF) compared to CMs from normal epithelial cells. Finally, we show that the histamine-containing cell differentiation of HL-60 cells as well as the colony growth induced by EpCM can be fully inhibited by preincubating this CM with a monoclonal neutralizing antibody to human GM-CSF. These studies: (a) illustrate the ability of human upper airway epithelial cells to secrete GM-CSF in vitro; (b) demonstrate differences between normal and inflamed tissue-derived epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1991

Allergen-induced asthmatic responses. Relationship between increases in airway responsiveness and increases in circulating eosinophils, basophils, and their progenitors.

The inflammatory response during allergen-induced asthma was assessed using serial measures of peripheral blood eosinophils (Eo), basophils (B), and Eo/B progenitor cells (Eo/B-CFU). A group of 14 stable asthmatic individuals (beta 2-agonists only as needed) had inhalation provocation tests with allergen (18 tests in total) and with diluent. Serial blood samples were taken before and 1 and 24 h after the tests; methylcellulose cultures for Eo/B-CFU and granulocyte-macrophage (GM-CFU) were scored at 14 days. Circulating Eo, B, and Eo/B-CFU were increased at 24 h after allergen inhalation when this resulted in increased histamine airway responsiveness (n = 13). In the 5 subjects with isolated early asthmatic responses the Eo, B, and Eo/B-CFU counts did not change. There was no change in the GM-CFU after allergen. The ratio change in circulating Eo/B-CFU was negatively correlated with baseline histamine airway responsiveness (r = -0.8, p less than 0.05). Four subjects who had an isolated early response and no blood changes to one allergen developed an increase in histamine airway responsiveness and an increase in Eo, B, and Eo/B progenitors after inhalation of a second different allergen. The results indicate that in subjects with an allergen-induced increase in histamine airway responsiveness, an inflammatory response occurs that includes an increase in the number of Eo/B progenitors. This response, possibly mediated by Eo/B growth and differentiation factors, could lead to the accumulation of these cells in the airway and contribute to the airways inflammation present in asthma.

Allergens↗
PubMed1991

Neutrophilic differentiation induced by human upper airway fibroblast-derived granulocyte/macrophage colony-stimulating factor (GM-CSF).

We have established primary lines of fibroblasts from nasal polyp (NP) tissues as well as from normal nasal (NN) mucosa and have examined the ability of these cells to release hormone-like peptide messenger molecules (cytokines). Our results show that human upper airway fibroblasts release granulocyte/macrophage colony-stimulating factor (GM-CSF), granulocyte-CSF (G-CSF), and macrophage-CSF (M-CSF) in vitro. We also show that fibroblasts derived from NP tissue express the gene for GM-CSF at a higher level, and release the GM-CSF product in greater amounts, than NN fibroblasts. In addition, we have examined the ability of these fibroblasts and their conditioned medium (CM) to induce differentiation of human hemopoietic progenitor cells. After 7 d, cultures of these cells in RPMI-10% fetal bovine serum contained 5 +/- 2.5% (mean +/- SD) neutrophils. In contrast, culture of progenitor cells with fibroblasts resulted in significantly greater neutrophilic differentiation (18 +/- 4%). Culture in fibroblast-CM induced a similar degree of differentiation, and fibroblast-CM from NP fibroblasts elicited greater differentiation compared to CM from NN fibroblasts (17.5 +/- 3 versus 12 +/- 3%). The neutrophilic differentiation induced by fibroblast-CM can be fully inhibited by preincubating this CM with a monoclonal neutralizing antibody to human GM-CSF. Thus, our results demonstrate: (1) the ability of human upper airway fibroblasts to release GM-, G-, and M-CSF in vitro; (2) that fibroblasts derived from NP tissues express the gene and release the product GM-CSF at greater levels compared to NN fibroblasts; and (3) that fibroblast-derived GM-CSF causes neutrophilic differentiation of human hemopoietic progenitors.

Animals↗
PubMed1991

Monocyte-macrophage differentiation induced by human upper airway epithelial cells.

We examined the ability of conditioned medium (CM) generated by human upper airway epithelial (Ep) cells from normal (NN) and inflamed, allergic rhinitis (AR) and nasal polyp (NP) tissues to induce monocytic differentiation of hemopoietic progenitors of the HL-60 myeloid leukemia cell line in vitro. In HL-60 cells cultured in RPMI with 10% FBS, there was differentiation to 0.4 +/- 0.4% monocytic cells. NN-, AR-, and NP-EpCM induced differentiation to 23 +/- 6%, 42 +/- 11%, and 71 +/- 10% monocytic cells, respectively. EpCM also induced isolated peripheral blood nonadherent mononuclear cells to express monocyte/macrophage-specific antigens as detected by immunohistochemistry using FMC-32 monoclonal antibodies (anti-CD14). We also examined the cytokine content of these EpCMs and found that they contained granulocyte/macrophage colony-stimulating factor (GM-CSF): 126 +/- 35, 198 +/- 22, and 489 +/- 118 pg/ml for NN-, AR-, and NP-EpCM, respectively. These CMs also contained granulocyte-CSF (G-CSF) and interleukin-6 (IL-6), but there were no significant differences between normal and inflamed tissue-derived cell supernatants. No macrophage-CSF (M-CSF) was detected in these EpCMs. Recombinant human GM-CSF, G-CSF, and IL-6, alone and in combinations, at doses similar to or greater than those found in the EpCMs, did not induce comparable monocytic differentiation of HL-60 cells. Preincubation of the EpCM with neutralizing anti-GM-CSF, anti-G-CSF, or anti-IL-6 antibodies did not significantly inhibit the monocytic differentiation induced by the EpCM.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Differentiation↗
PubMed1991

Promotion of eosinophil survival by human bronchial epithelial cells and its modulation by steroids.

Accumulation of eosinophils in the bronchial tissue occurs in a variety of inflammatory disorders of the human airway. We asked whether airway epithelial cells released factors that could influence eosinophil survival and thus contribute to accumulation of these cells in the tissues. Using conditioned medium (CM) generated from cultured human bronchial epithelial cells (HBEC), we examined the in vitro survival of eosinophils isolated from human peripheral blood. When cultured in control medium, more than 90% of the eosinophils were dead by day 4. In contrast, culture in HBEC-CM resulted in dose-dependent survival at day 6 of 69 +/- 9.4%, 40.5 +/- 5.9%, and 25 +/- 2% viability with 2, 0.5, and 0.1% HBEC-CM, respectively (n = 4). Granulocyte/macrophage colony-stimulating factor (GM-CSF) was detected in the HBEC-CM by enzyme-linked immunosorbent assay at levels of 22 to 48 pg/ml. Furthermore, preincubation of the HBEC-CM with a neutralizing monoclonal antibody to human GM-CSF completely inhibited this increased survival of eosinophils. Because corticosteroids are potent eosinopenic agents, we also examined the effects of the synthetic steroid budesonide on this system. Budesonide inhibited both spontaneous and interleukin-1 (IL-1)-induced GM-CSF production by cultured HBEC. In addition, preincubation of eosinophils with budesonide caused marked abrogation of the survival induced subsequently with either HBEC-CM or recombinant human GM-CSF. In summary, HBEC can support eosinophil survival via the elaboration of GM-CSF and thus may contribute to the local control of inflammatory cell accumulation. Steroids may modulate this process both by inhibiting cytokine production from HBEC and by a direct effect on eosinophils, preventing their response to cytokines.

Antibodies↗
PubMed1991

Granulocyte/macrophage colony-stimulating factor (GM-CSF) gene expression by eosinophils in nasal polyposis.

Nasal polyposis is a chronic inflammatory condition of the upper airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. Granulocyte/macrophage colony-stimulating factor (GM-CSF) is a cytokine with powerful biologic effects including the regulation of survival, proliferation, and activation of granulocytes as well as differentiation of hemopoietic cells. To examine the potential role of GM-CSF in the pathogenesis of this condition, we investigated gene expression and production of GM-CSF in nasal polyp tissues as well as in the normal nasal mucosa. Immunoreactive GM-CSF was detected by enzyme-linked immunosorbent assay in the 24-h supernatant of nasal polyp tissues placed in culture. By Northern blot analysis and Southern blot analysis following a reverse-transcription polymerase chain reaction using a human GM-CSF cDNA probe, we detected GM-CSF mRNA in nasal polyp tissues, as well as in the tissue from a patient with allergic rhinitis, but not in the normal nasal mucosa. By in situ hybridization using the same probe, cells expressing mRNA specific for GM-CSF were observed in nasal polyp tissues and in the allergic nasal mucosa. In addition, by the combination of in situ hybridization and counterstaining with chromotrope 2R, we demonstrated that approximately 30% of eosinophils infiltrating the polyp tissue express the GM-CSF gene. These results suggest a novel mechanism by which eosinophils may contribute to the pathogenesis of chronic inflammatory diseases such as nasal polyposis, allergic rhinitis, and, by implication, asthma.

Base Sequence↗
PubMed1991

Nasal polyposis: in search of a viral etiology using DNA hybridization.

The etiology of nasal polyps is unknown. Numerous theories have been proposed, with allergic and infectious causes predominant. A viral theory was postulated almost 40 years ago. In a pilot project, we studied 15 subjects comprising six controls and nine patients with nasal polyps. No known viruses were cultured from the nasal polyp tissue or nasal mucosal biopsies from the control subjects. DNA Hybridization for Epstein-Barr Virus, Herpes simplex virus, adenovirus type V, and Chlamydia trachomatis were also negative for all tissue studied. The use of molecular biological techniques is not widespread in otolaryngology and this is the first report, to the best of our knowledge, of the application of these techniques for the investigation of the viral etiology of nasal polyps.

Adult↗
PubMed1991

Evaluation of the burden of illness for pediatric asthmatic patients and their parents.

To examine the quality-of-life burden of asthma in a pediatric population, we systematically surveyed 100 patients with moderate asthma and one parent of each patient to determine the impact of the disease on day-to-day life. We found that perceptions of burden of illness varied by viewpoint. For patients, the symptoms of asthma form the largest component of the burden of the disease; in addition, more than half of the sample listed various emotional function items that were of at least moderate bother to them. Parents cited worry and concern about the disease and the medications used to treat it and their inability to relieve their child's symptoms as the major components of the burden of the disease. We conclude that although pediatric patients with moderate asthma find the respiratory symptoms of the disease troublesome, few children perceive that their asthma poses a major disruption of their lives. For the parents of these patients, strategies could be implemented by clinicians to ease the common worries and concerns surrounding the child's asthma.

Adolescent↗
PubMed1990

Sputum cell counts in airway disease: a useful sampling technique.

Quantitative sputum cell counts from patients with asthma and chronic bronchitis were performed and found to be reproducible. Sputum from carefully characterized subjects with asthma contained large numbers of eosinophils and formalin-sensitive metachromatic (mast) cells. In contrast, the macrophage was the dominant cell type in the sputum from smokers with chronic bronchitis. In a third group of patients with corticosteroid responsive-chronic cough and normal methacholine airway responsiveness the sputum contained eosinophils and metachromatic cells, similar to the asthmatic subjects. Sputum cell counts are a useful, noninvasive method for the identification of this pattern of inflammatory response in patients with airway diseases.

Humans↗
PubMed1990

The role of measurements of airway responsiveness.

In smokers with chronic airflow limitation (CAL), airway hyperresponsiveness (AHR) to stimuli like methacholine, which act directly on airway smooth muscle, are not specific for the pathogenesis which is responsible for AHR to methacholine in subjects with normal spirometry, nor predictive for a beneficial effect of glucocorticosteroid (GCS) treatment. In contrast, AHR to stimuli like hyperventilation, which act indirectly through mediator release, may be specific for the pathogenesis of asthma and predictive for a beneficial effect of GCS. The validation of this possibility requires the demonstration that patients with CAL and AHR to hyper-ventilation demonstrate improvement after treatment with GCS (and have an increase in eosinophils and metachromatic cells in the sputum or bronchoalveolar lavage (BAL), like that seen in asthmatics uncomplicated by CAL).

Asthma↗
PubMed1990

Occupational asthma caused by guar gum.

Some vegetable gums have been reported to cause asthma. We describe three subjects who were exposed at work to guar gum, which is derived from the outer part of Cyanopsis tetragonolobus, a vegetable that grows in India. The first subject worked for a pharmaceutical company; the second and third subjects worked at a carpet-manufacturing plant. All three subjects developed symptoms of rhinitis and asthma after the onset of exposure to guar gum. All subjects were atopic and demonstrated mild bronchial hyperresponsiveness to inhaled histamine at the time they were observed. Skin prick tests demonstrated an immediate skin reaction to guar gum. All three subjects had high levels of serum IgE antibodies to guar gum. Specific inhalation challenges in which the three subjects were exposed for short intervals (less than or equal to 4 minutes) to powder of guar gum elicited isolated immediate bronchospastic reactions in two subjects and a dual reaction in the other subject.

Adult↗
PubMed1990

A double-blind comparison of intranasal budesonide with placebo for nasal polyposis.

Intranasal budesonide, 400 micrograms two times a day, was evaluated in 36 patients referred for treatment of nasal polyposis. The age range was 20 to 68 years. Polypectomy was done 5.6 (mean) times previously. After a 5-week, treatment-free, baseline period, patients were treated in a double-blind fashion with either budesonide or placebo during 4 weeks. After this treatment period, placebo-treated patients started receiving budesonide in an open trial for an additional 4 weeks. The patients rated their nasal symptoms daily. Nasal examinations and nasal inspiratory flow rate (IFR) measurements were done at clinic visits. After 3 and 4 weeks of treatment, the response to budesonide was significantly greater than response to placebo. The greater reduction in nasal blockage caused by polyps, observed on physical examination, p = 0.005, was mirrored by an increase in nasal IFR (p = 0.0001). Patient rating of the severity and frequency of nasal blockage were reduced more by budesonide than by placebo (p less than or equal to 0.0005). Switching placebo-treated patients to budesonide treatment resulted in a reduction of nasal blockage (p less than 0.001) and an increase in nasal IFR (p less than 0.001). The results demonstrate that topical nasal budesonide, 400 micrograms two times a day, is an effective treatment of nasal polyps.

Administration, Intranasal↗