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Biomedical subjects

J Brostoff

Publications and source records attributed to J Brostoff.

At least 109 records · Page 6Linked to original sources
PubMed1981

Allergenic activity of fractions of cocksfoot (Dactylis glomerata) pollen. Definition of active components by skin testing, and inhibition RAST.

With the combined use of skin tests, RAST and isoelectric focusing, a potency profile of a cocksfoot ((Dactylis glomerata) pollen extract was prepared. It was found that two fractions with pI 4.5 and 6.0 were the most allergenic, had the highest protein concentration and were also the most easily extracted. The importance of converting mean weal sizes into potency units when comparing the allergenicity of pollen fractions is emphasized.

Allergens↗
PubMed1981

HLA dependence of sensitivity to nickel and chromium.

A group of patients with cutaneous sensitivity was compared with another group with cement dermatitis who showed sensitivity to chromate. HLA typing for A and B locus antigens demonstrated a 29% incidence of B21 in the nickel sensitive group (control population 4.9%) and the antigen was not found in 16 patients with chromium sensitivity. It is suggested that this may represent a hapten specific HLA dependent immune response in man.

Chromium↗
PubMed1981

T gamma cells in sarcoidosis: E rosetting monocytes suppress lymphocyte transformation.

Increased suppressor T gamma lymphocytes have been described in sarcoidosis. We have shown that a proportion of these cells are esterase-positive, phagocytic, adherent to plastic and stain with an anti-monocyte serum. Removal of these cells or the addition of indomethacin increases the lymphocyte transformation to Con A. Transformation was still reduced in spite of preincubation with plastic and the addition of indomethacin suggesting that a further abnormality exists. Thus, within the increased number of T gamma cells there exists a population of activated monocytes which rosette with sheep red blood cells and could therefore be mistaken for T cells.

Adult↗
PubMed1980

Food allergy in migraine. Study of dietary exclusion and RAST.

Two-thirds of severe migraineurs were allergic to certain foods, shown by dietary exclusion and subsequent challenge. Radioallergosorbent test confirmed the relevance of these foods. Oral sodium cromoglycate protected these patients from food challenges. The initial specific allergic reaction in the gut may result in increased mucosal permeability which allows food antigens, complexes, or mediators to be absorbed and cause symptoms.

Antigens↗
PubMed1980

The atopic syndrome: in vitro immunological characteristics of clinically defined subgroups of atopic subjects.

Total IgE, selected specific IgE antibody levels, C2 and yeast opsonization were measured in four clinically defined subgroups of atopic patients who had previously been HLA-typed. Each group was characterized by a distinctive mean total IgE level and profile of specific IgE responses. All groups gave comparable levels of IgE antibodies to Timothy grass pollen but in patients initially presenting with infantile eczema and who subsequently developed asthma and/or hay fever, IgE antibodies to bovine milk proteins, egg ovalbumin and cat dander were frequently observed whereas in patients initially presenting with hay fever later in life these antibodies were usually absent. Computer assisted analysis failed to show any association between IgE antibody responses and (a) the HLA phenotypes A1,B8 and A3,B7 (b) C2 levels and (c) the yeast opsonization index.

Adult↗
PubMed1980

Histamine suppression of lymphocyte activation.

Histamine suppresses lymphocyte transformation induced by the mitogen Con A. The effect is dose-related and is not blocked by H1 or H2 antagonists. High dose of H2 antagonists (10(-3) M) enhances the suppression induced by histamine. The proliferation of T cells alone cultured with histamine is suppressed indicating that histamine can exert its effect directly on T cell proliferation without the requirement for accessory cells. Atopic subjects are more sensitive to histamine-induced suppression than normals. The presence of histamine produced locally during a Type I response may provide a mechanism for preventing the proliferation of sensitized T cells which enter the site of antigen stimulation. In the atopic, who already has the immunological machinery to mount cell-mediated immune responses to pollens, this increased histamine sensitivity may be protective in suppressing unwanted delayed hypersensitivity reactions.

Adult↗
PubMed1979

Production of IgE complexes by allergen challenge in atopic patients and the effect of sodium cromoglycate.

Specific IgE complexes and symptoms of asthma and eczema were produced in two allergic patients by oral challenge with food allergen. Both symptoms and IgE complexes could be prevented by pre-treatment with oral sodium cromoglycate. The IgE complexes can fix complement and may therefore provide the vehicle of the "late" responses seen in immediate hypersensitivity. The central role of gut sensitivity is emphasised by the protection afforded by sodium cromoglycate both when given acutely, against the effects of an oral challenge, and when given continuously for asthma and eczema due to food allergy.

Adult↗
PubMed1979

Immune complexes containing food proteins in normal and atopic subjects after oral challenge and effect of sodium cromoglycate on antigen absorption.

After ingestion of food, immune complexes containing food proteins as antigens were demonstrated in the serum of normal and atopic subjects. In the atopic patients challenged with the food to which they were sensitive, abnormal levels were detected. The same atopic patients pretreated with oral sodium cromoglycate had less antigen entry, diminished immune-complex formation, and no atopic symptoms. Tests for antigen entry and immune-complex formation after oral challenge may permit objective assessment of food allergy and may show whether drugs such as oral sodium cromoglycate are likely to benefit individual patients.

Absorption↗
PubMed1979

An anomalous effect of allergen concentration on weal size elicited by skin testing for immediate hypersensitivity.

We report the finding of anomalous responses in the skin of atopic individuals when prick tested with serial dilutions of cocksfoot grass pollen extracts. Each pollen extract was standardized using RAST inhibition activity related to the WHO standard for IgE. 75% of the patients gave a larger weal area with an allergen concentration of 1:10(5) than with the next higher concentration, i.e. 1:10(4). Possible mechanisms whereby a larger skin weal is elicited with a lower concentration of allergen are discussed. This is not a rare finding and can be observed in patients undergoing routine skin testing in the clinic, even where extracts are diluted over a relatively narrow concentration range.

Allergens↗
PubMed1979

'Barn allergy': asthma and rhinitis due to storage mites.

The differential diagnosis of asthma in farm workers is between a type I hypersensitivity to a pollen or dust allergen and a type III hypersensitivity to mould antigens. We describe asthma and rhinitis, and not farmer's lung, in a farming population due to the non-pyroglyphid grain storage mite. Before a diagnosis of farmers' lung due to mouldy hay is made in any patient whether or not precipitins to Micropolyspora faeni are present, skin tests for storage mite should be made. If these are positive a diagnosis of 'barn allergy' should be considered and a trial of sodium cromoglycate be given.

Adolescent↗
PubMed1979

Standardization of radioallergosorbent test (RAST) and allergen extracts in terms of the WHO standard for IgE.

An 131I-labelled IgE myeloma, standardized against the WHO reference serum for IgE was bound in varying concentrations to discs bearing anti-human light chain. These were used to construct a calibration curve for the subsequent binding of 125I-labelled anti-IgE, thus relating 125I counts to WHO IgE units. The calibrated anti-IgE could then be used to measure the actual amount of specific IgE bound to an allergen disc in the radioallergosorbent test. Using this standardized system, soluble allergen extracts could then be assayed by their ability to inhibit the binding of a defined amount of specific IgE, thereby enabling their activity to be expressed in WHO IgE units.

Allergens↗
PubMed1978

Skin-test anomaly.

Explore the source record for details and available documents.

Dose-Response Relationship, Immunologic↗
PubMed1978

Allergenic activity of fractions of cocksfoot (Dacylis glomerata) pollen.

A cocksfoot (Dactylis glomerata) pollen extract has been fractionated by isoelectric focusing in polyacrylamide gel, the separated components extracted from the gel and assayed by three methods: prick tests in human skin, RAST and PCA tests in monkey skin. Prick testing in human skin showed that subjects responded differently to the separated components, indicating the presence of more than one antigenic determinant, and a profile of antibody activity against each fraction could be constructed. In general, good agreement was observed between RAST profiles and skin test profiles, although some patients who gave positive skin tests lacked circulating IgE and consequently did not give a RAST profile or a monkey PCA. These studies emphasize the current difficulty in attempting to isolate a single pure allergen from cocksfoot which can be used either diagnostically for the detection of pollen allergy, or for the standardization of diagnostic extracts.

Adolescent↗
PubMed1978

Do fatty acids exert a specific effect on human lymphocyte transformation in vitro?

Both saturated and unsaturated fatty acids (FA) bound to albumin inhibit phytohaemagglutinin (PHA) transformation of human lymphocytes cultured in fetal calf serum (FCS). With two unsaturated FA inhibition is maintained, however, when saturated and unsaturated FA are added simultaneously the inhibition is abolished. When lymphochtes are cultured in human AB serum, fatty acids neither inhibit nor stimulate PHA transformation. The reasons for the difference between FCS and human serum are discussed. These results argue against reports that unsaturated FA plays an immunoregulatory role in humans.

ABO Blood-Group System↗