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Biomedical subjects

H F Kauffman

Publications and source records attributed to H F Kauffman.

At least 127 records · Page 7Linked to original sources
PubMed1987

The beta-adrenergic system of non-allergic patients with chronic airflow obstruction and early morning dyspnoea.

Lymphocyte beta-adrenergic receptor function and urinary excretion of catecholamines were measured in eight non-allergic patients with partially reversible chronic airflow obstruction (CAO) and early morning dyspnoea (EMD), and in eight matched healthy control subjects. In order to establish a possible relationship between the early morning dyspnoea and a reduced beta-adrenergic activity, these parameters were measured during the "morning dip" in FEV1 and in the afternoon, when lung function is maximal. No differences were observed for lymphocyte beta-adrenergic receptor characteristics (beta-receptor number, Kd, for 3H-dihydroalprenolol, and cAMP response to isoproterenol) between patients and controls, when determined at 8 AM or at 4 PM. Nor was there a significant circadian variation in these parameters present in both groups. By contrast, the patients showed a significantly reduced urinary excretion of epinephrine and norepinephrine, as measured in four-hourly urine portions collected between 8 and 12 AM and between 4 and 8 PM, respectively. In addition, the urinary excretion of epinephrine showed a significant circadian variation in the patients, which was correlated with the FEV1 (% predicted). Such a relationship was not found for norepinephrine. The results suggest that a (generalized) dysfunction of the beta-adrenergic receptor is not involved in the pathogenesis of CAO or EMD. However, reduced beta-adrenergic receptor stimulation due to decreased levels of catecholamines may contribute to the observed (variation in) airflow obstruction of the patients.

Adult↗
PubMed1986

Phorbol 12-myristate 13-acetate induces beta-adrenergic receptor uncoupling and non-specific desensitization of adenylate cyclase in human mononuclear leukocytes.

Tumour-promoting phorbol esters such as phorbol 12-myristate 13-acetate (PMA) have been reported to modulate beta-adrenergic receptor responses in various cell types, presumably by the activation of protein kinase C. In the present investigation we assessed the effect of PMA on the beta-adrenergic receptor-adenylate cyclase system of human mononuclear leukocytes (MNL). It was found that incubation of MNL with PMA resulted in a time- and concentration-dependent desensitization of isoproterenol-induced adenylate cyclase activity. However, the effect of PMA was not restricted to the beta-adrenergic receptor system, since basal adenylate cyclase activity and histamine-, prostaglandin E1-, 5'-guanylylimidodiphosphate (GppNHp)-, and NaF-stimulated values were also reduced. By contrast, no effect was found on the forskolin-induced adenylate cyclase activity. The inactive phorbol ester, 4 alpha-phorbol 12,13-didecanoate had no effect on adenylate cyclase at all, suggesting that the observed PMA effect was specifically mediated by activation of protein kinase C. The reduced beta-adrenergic response induced by PMA was not associated with a reduced beta-adrenergic receptor number, indicating uncoupling of this receptor from adenylate cyclase. Isoproterenol competition curves for 3H-dihydroalprenolol binding to membranes from untreated and PMA-treated cells demonstrated that the uncoupling was due to a reduced ability of the agonist to promote formation of the guanine nucleotide-sensitive high affinity state of the receptor. The results indicate that PMA may cause desensitization of catecholamine-responsive adenylate cyclase in MNL, and that the major locus of alteration is the guanine nucleotide regulatory protein.

Adenylyl Cyclases↗
PubMed1986

Class-specific antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. III. Comparative study: IgG, IgA, IgM ELISA titers, precipitating antibodies and IgE binding after fractionation of the antigen.

IgG, IgA and IgM ELISA antibody titers against Aspergillus fumigatus were elevated in sera of patients with aspergilloma and allergic bronchopulmonary aspergillosis (ABPA), showing higher titers for the IgG antibodies compared with the IgA and IgM antibodies. No differences were found between titers of identical antibody classes in the two groups of sera. IgG and IgA ELISA titers were highly specific whereas IgM ELISA showed more unspecific binding of IgM antibodies. Antibodies, as measured by ELISA, studied after fractionation of the antigen into fractions of decreasing molecular weight, showed a preferential binding by the high molecular weight fractions. Precipitating antibodies studied in patient sera did not always correspond with the IgG ELISA titers. IgE antibody binding was observed in all fractions from Sephadex G-100 fractionated components; maximum binding was found with fractions of 28,000-60,000 daltons. The low molecular weight fractions (18,000-less than 5,000 daltons) showed less IgE binding but the quantity of this fraction was higher. The discrepancies noted between the IgG and IgA ELISA titers and the binding of IgM or IgE antibodies indicate that antigenic components may in part differ in the binding of antibody classes.

Antibodies, Fungal↗
PubMed1986

Specific immunological modulation of lymphocyte adenylate cyclase in asthmatic patients after allergenic bronchial provocation.

Adenylate cyclase responses to isoproterenol, histamine, 5'-guanylylimidodiphosphate (GppNHp) and NaF were measured in lymphocyte membranes of allergic asthmatic patients and healthy control subjects, just before and 24 h after inhalation challenge with house dust mite allergen or histamine. In the nonacute phase before the challenges, the adenylate cyclase responses in the cell membranes of the patients were not significantly different from those in membranes of the control subjects. House dust mite challenge caused a significant decrease of all adenylate cyclase responses in the cell membranes of the patients by about 40-50%. By contrast, histamine provocation of the patients had no effect on these parameters, nor was there any effect of both challenges on the adenylate cyclase activity of the control membranes. The results indicate that allergen-induced asthmatic reactions may cause nonspecific refractoriness of lymphocyte adenylate cyclase. Since histamine-induced bronchial obstruction had no effect in the patients, it appears that the adenylate cyclase response is specifically modulated by the allergic process.

Adenylyl Cyclases↗
PubMed1986

The eosinophilic granulocyte an active participant in the late phase asthmatic reaction?

The role of the eosinophilic granulocyte in immediate hypersensitivity reactions is generally believed to be a beneficial one since this cell may phagocytose mast cell granules and inactivate certain mast cell mediators. However it has become clear that the eosinophilic granulocyte also has potent secretory capacities, and by this property may contribute in a detrimental way to the allergic process. In studying the late phase allergen induced bronchoconstriction by means of bronchoalveolar lavage (BAL) an evident infiltration of eosinophilic granulocytes in the bronchioli in the beginning of the late phase asthmatic reaction was noticed. Since also eosinophil cationic protein (ECP) has been reported to be elevated in the lavage fluid an active secretory role of the eosinophil in the late phase asthmatic reaction seemed likely. Although the release of ECP and other granular proteins may contribute to epithelial damage and inflammation and thereby to an increase in bronchial hyperreactivity they do not explain the late phase bronchoconstrictive reaction. Since leukotrienes were thought possible candidates to cause this reaction it was decided to isolate eosinophils from human peripheral blood and to study their leukotriene synthesis pattern. To our surprise purified human eosinophils almost exclusively synthesize the strongly bronchoconstrictive leukotriene LTC4 in considerable quantities upon in vitro stimulation with either the calcium-ionophore A23187 or opsonized zymosan. These findings suggest that the eosinophil may play an active role in causing the late phase asthmatic reaction.

Asthma↗
PubMed1985

Histamine in late asthmatic reactions following house-dust mite inhalation.

In order to investigate the role of histamine in the late asthmatic reaction (LAR) following house-dust mite (HDM) inhalation, we studied, with hourly intervals, urinary N tau-methylhistamine (an important metabolite of histamine) in 14 allergic asthmatic patients before and after broncho provocation with HDM. Four patients showed an early asthmatic reaction (EAR), while 10 patients developed a LAR as well. In the hour following the EAR a significant increase in urinary N tau-methylhistamine was observed as compared to the control day (0.01 less than p less than 0.05). During the LAR no increase of this metabolite was detected in the urine of the patients. Additionally, histamine was measured in broncho alveolar lavage fluid (BAF) obtained from 6 patients during the HDM-provoked LAR and compared to histamine levels in BAF from patients without a LAR, following broncho provocation. In the LAR group higher histamine levels were found than in the other patient and control groups. For the whole patient group no correlation was found between the degree of bronchial obstruction during the LAR and the BAF histamine values. No difference was found in N tau-methylhistamine in BAF between patients with LAR and controls. Thus histamine metabolite studies in the urine failed to provide evidence of involvement of histamine in the LAR, while further data are needed to interpret the results of local sampling in the lung.

Adolescent↗
PubMed1985

Standardization of house dust mite extracts. Liberation of allergenic and antigenic components in relation to extraction conditions.

The spontaneous release of house dust mite components from cultures of Dermatophagoides pteronyssinus into slightly buffered water was studied against time, using both continuous and discontinuous extraction procedures. It was shown that proteins, carbohydrates, IgE binding components and precipitating antigenic components were rapidly released from the house dust mite cultures, reaching a maximal liberation within 1 h of extraction. Repeated extractions of house dust mite cultures (discontinuous extraction) showed an additional release of IgE components but the IgE binding potency declined after successive extractions, while showing increasing release of immunological inactive components. IgE binding to antigens immobilized to polystyrene surfaces (IgE-ELISA) appeared to be less sensitive compared with cyanogen-bromide activated discs (IgE-RAST). It was concluded that extraction procedures of house dust mite cultures with short incubation time of 1 h or less are to be preferred.

Allergens↗
PubMed1985

Volumetric aerobiological survey of conidial fungi in the North-East Netherlands. I. Seasonal patterns and the influence of metereological variables.

In order to obtain actual data about the qualitative and quantitative occurrence of airborne fungi in The Netherlands, a viable-volumetric sample survey with the Andersen sampler was undertaken. From April 1981 to the end of June 1983, one day a week samples were taken on the unobstructed rooftop of a hospital in the N-E Netherlands. An average of 268 Colony Forming Units (CFU), per sample, per cubic metre of air were found. Almost three-quarters of the total catch consisted of seven genera, Cladosporium predominating. Botrytis showed in surprisingly high numbers when compared with other surveys, while Alternaria occurred in very low concentrations. Most atmospheric airborne spora were found between May and September. Aspergillus and Penicillium prevailed in the autumn and winter months, although were present the year-round. Momentary weather conditions seemed less important for the overall spore picture than the average meteorological characteristics for a whole season. The obtained aero-mycological information may be useful in determining clinical strategies for skin testing and serological investigations in patients with suspected mould allergies.

Air Microbiology↗
PubMed1985

Volumetric aerobiological survey of conidial fungi in the North-East Netherlands. II. Comparison of aerobiological data and skin tests with mould extracts in an asthmatic population.

A study was undertaken to see whether the principal airborne fungi in the North-East Netherlands were also found to be the most reactive in skin testing. Atmospheric samples were taken weekly with the Andersen sampler, from April 1981, up to and including, June 1983. At the same time skin tests of 833 patients referred to the outpatient Departments of Pulmonology and Allergology, because of recurrent bronchial obstructive complaints and a suspected allergy, were studied for strongly positive skin reactivity to fungi. 4.6% of the patients reacted with a wheal of 10 mm diameter or more to one or more of the tested fungi. Almost three-quarters of the airborne fungal "flora" was composed of seven genera, namely (in order of occurrence): Cladosporium (42.6%), Botrytis (8.6%), Yeasts (7%), Penicillium (5.8%), Basidiomycetes (5.7%), Aspergillus (3.7%), and Alternaria (0.9%). In skin-testing, however, a different order of occurrence existed: namely: Beauveria (6.8%), Botrytis (6.1%), Aspergillus (4.7%), Mucor (3.8%), Epicoccum (3%), Cladosporium (2.3%), and Alternaria (1.1%). It is concluded that the most prevailing airborne moulds are not necessarily the most potent allergens, at least in skin testing. Aspergillus and Botrytis showed a high sensitization rate, while Cladosporium and Alternaria did not. Botrytis deserves further study because of its frequent airborne occurrence and marked allergenic properties.

Air Microbiology↗
PubMed1985

Cultivation of fungi in synthetic and semi-synthetic liquid medium. I. Growth characteristics of the fungi and biochemical properties of the isolated antigenic material.

Four allergologically important fungi, viz. Aspergillus fumigatus, Alternaria Penicillium notatum, and Cladosporium herbarum, were cultured in a pure synthetic medium and the patterns of growth as characterized by the pH, protein and carbohydrate concentration of the culture fluid, were studied. A fumigatus and P. notatum showed a similar growth pattern, characterized by a rapid decrease in the pH of the culture medium (pH 7.4----4.0), while proteins were slowly released and saccharose poorly consumed. In contrast, A. alternata and C. herbarum demonstrated a different pattern of growth, in which the pH of the culture hardly changed during incubation. Enrichment of the synthetic medium with yeast extract greatly improved the growth of all four fungi, as was confirmed by the enhanced yield of antigenic material and strongly increased consumption of saccharose. The yeast extract especially changed the growth pattern of A. fumigatus and P. notatum, which now is characterized by three phases. Phase I: fall in pH of the growth medium and excretion of proteins; phase II: increase in pH and fall in protein concentration; phase III: stabilization of pH at alkaline values and renewed excretions of proteins. It is concluded that during cultivation of the fungi, the metabolic state of the culture changes, influencing the antigenic composition of the extracts obtained after different periods of cultivation.

Antigens↗
PubMed1985

Cultivation of fungi in synthetic and semi-synthetic liquid medium. II. Immunochemical properties of the antigenic and allergenic extracts.

Four allergologically important fungi, viz. Aspergillus fumigatus, Penicillium notatum, Alternaria alternata, and Cladosporium herbarum were cultured in a liquid synthetic medium, with or without addition of 0.1% yeast extract (YE). After 10 and 28 days of cultivation, immunochemical properties of the fungal extracts, characterised by precipitation pattern and IgG- and IgE-binding capacity, were studied. In pure synthetic medium no large differences were observed in number of precipitates, as measured by DID, among the four antigenic fractions of each fungus (metabolic and mycelial antigens of both early and late phase cultures). Addition of YE to the growth medium hardly changed the number of precipitates and generally caused a decrease in IgG-binding capacity of the extracts. In contrast to these observations were the findings with the IgE-binding capacities of the fungal extracts as measured by RAST. Most allergenic fractions demonstrated an increase (sometimes strong) in IgE-binding capacity after YE was added to the growth medium. It is concluded that the time of cultivation influences the immunochemical characteristics of fungal extracts and that mycelial as well as metabolic antigens of both early and late phase cultures should be used in order to obtain a wide spectrum of allergens in extracts used for diagnostic purposes.

Allergens↗
PubMed1985

Reduced adenylate cyclase responsiveness to histamine in lymphocyte membranes of allergic asthmatic patients after allergen challenge.

The adenylate cyclase response to histamine was measured in lymphocyte membranes of allergic asthmatic patients and healthy control subjects, just before and 24 h after inhalation challenge with house dust mite allergen. In the non-acute phase before allergen challenge, the histamine response in the membranes of the patients was not significantly different from that in membranes of the control subjects. After the house dust mite-induced asthmatic reaction, however, the adenylate cyclase response to histamine in the membranes of the patients was significantly reduced by 47%, whereas allergen inhalation had no effect on the histamine response of the control membranes. The results suggest that allergic asthmatic reactions may cause reduced lymphocyte adenylate cyclase responsiveness to histamine. A similar mechanism in the airways might contribute to allergen-induced enhanced airway reactivity to histamine.

Adenylyl Cyclases↗
PubMed1985

Antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. I. Liberation of polystyrene binding components during cultivation.

The liberation of polystyrene binding antigenic components (PBC) of Aspergillus fumigatus involved in ELISA IgG measurements was studied during cultivation in the culture filtrates. PBC were rapidly liberated into the culture medium during the logarithmic phase of growth (phase I), were in part degraded or reconsumed during the stationary phase (phase II) and again secreted (other PBC) during the lytic phase (phase III). ELISA IgG titers and numbers of precipitating components are not always related with one another, may show an inverse relationship; maximal ELISA titers are reached during phase I when precipitating components are limited. The striking similarity between the liberation of PBC and IgE-binding components is discussed.

Antibodies, Fungal↗
PubMed1985

Antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. II. Physico- and immunochemical properties of the polystyrene-binding components.

Polystyrene-binding antigenic components (PBC) of Aspergillus fumigatus involved in ELISA IgG antibody determinations and the corresponding numbers of precipitates found by double immunodiffusion (DID) and/or crossed immunoelectrophoresis (CIE) were studied using culture filtrate antigenic preparations fractionated by Sephadex G-100 chromatography, concanavalin A (ConA) affinity chromatography, isoelectric focusing (IEF) and TCA precipitation. It is shown that PBC, immunologically active in ELISA, are characterized by high molecular weights and ConA-binding properties. The pI values of these components were 3.5-6 and above 8. The glycoprotein and/or mucopolysaccharide nature is suggested by the binding to ConA and their partial resistance to trichloroacetic acid treatment. By contrast, low-molecular weight components and antigenic components that are not absorbed by ConA being active in DID and/or CIE showed less or absence of binding to the polystyrene surface.

Antibodies, Fungal↗
PubMed1985

Bronchoalveolar eosinophilia during allergen-induced late asthmatic reactions.

In order to obtain information about the nature of the local inflammatory process during late asthmatic reactions after house dust mite inhalation, bronchoalveolar lavage (BAL) was performed in 19 asthmatic patients and in 5 control subjects. In 16 of the patients and in all of the control subjects, BAL was performed 6 to 7 h after allergen inhalation. Six of the patients showed early and late asthmatic reactions (LAR), 5 showed early reactions, and 5 showed no reactions. Bronchoalveolar lavage was also performed shortly after the early reaction in 5 patients with documented combined early and late reactions. In the BAL fluid of the patients with LAR, a significant eosinophilia (0.01 less than p less than 0.05) was found compared with that in all other patient groups and with that in the control subjects. This bronchoalveolar eosinophilia was accompanied by elevated eosinophil cationic protein/albumin ratio in the BAL fluid (0.01 less than p less than 0.05). These observations suggest that eosinophils and their mediators might be involved in the development of LAR after allergen inhalation.

Adult↗
PubMed1985

Standardization of allergenic extracts of Aspergillus fumigatus. Liberation of IgE-binding components during cultivation.

During cultivation of Aspergillus fumigatus a rapid liberation of IgE-binding components was found reaching maximum values during the logarithmic phase of growth (phase I). After a fall in IgE-binding titers during phase II, appearance of additional IgE-binding components was noted during the period of lysis of the microorganism (phase III). These latter allergenic components are different from the phase I IgE-binding components, as was shown by crossed-inhibition studies. The number of precipitating antigenic components was not related with the corresponding IgE-binding titers and showed an increase during all phases of growth. The rapid changes in both IgE- and IgG-binding properties and the discrepancies between precipitating properties and IgE binding are discussed in relation to standardization and quality control of aspergillus extracts.

Allergens↗