No abstract

Summary Skin (prick) and serological tests were made with enzyme preparations of Bacillus subtilis in exposed factory workers and potential ‘consumers’. Prick tests with these materials at 10 mg/ml gave positive immediate reactions in twenty‐six out of sixty‐five factory workers. Eighteen of the factory workers were classified as atopic because of allergy to common allergens and fifteen gave positive reactions to the enzymes compared with eleven out of forty‐seven non‐atopic workers. A group of eleven of the factory workers had consistent ventilatory impairment on repeated examination; all were prick test positive and seven were atopic, and four non‐atopic. Of 2500 patients attending for investigation of respiratory allergy, 40% were highly atopic, 40% moderately atopic and 20% non‐atopic. 80% were consumers of biological detergents. Only two gave weak, not clinically relevant, prick test reactions to the enzyme preparations. In radioallergosorbent (RAST) tests for specific IgE antibody against the enzyme preparations, counts in the present investigation of 600/30 sec or more corresponded best with prick test positivity, such values being found in twelve of the fifteen prick test positive atopics and in eight of the eleven workers with ventilatory impairment. Comparison of the RAST counts on sera from cord blood and from the patients who included non, light and heavy consumers showed increasingly higher specific IgE counts in these groups, although these counts were almost all below the level of 600/30 sec, which corresponded with skin test reactions and clinical relevance. Radioimmunodiffusion (RID) and radioimmunoelectrophoretic (RIEP) tests with enzyme preparations gave positive reactions only in the factory workers, of whom forty‐three had IgG and twenty‐one IgA antibody, none having only IgE antibody.

Summary A double‐blind statistically controlled study was carried out on ninety‐six patients with Type I allergy to D. pteronyssinus and a history of perennial asthma and/or rhinitis. Forty‐eight received injections of an extract of Dermatophagoides pteronyssinus and forty‐eight controls received injections of carbol saline. Both groups were closely comparable in all respects. Ninety‐one were available for assessment, forty‐six controls, and forty‐five treated. The D. pteronyssinus treated group showed a statistically significant decrease in nasal sensitivity to the mite extract after treatment and recorded less asthma, less use of drugs and an increased clinical tolerance of household dust. A significant rise in specific IgE to D. pteronyssinus was found in twenty‐three out of forty (58%) of the treated compared with eight out of forty‐one (20%) of the controls and a rise in total IgE in twenty out of forty (50%) of the treated compared with nine out of thirty‐nine (23%) of the control group. Specific IgG antibodies to D. pteronyssinus were found prior to treatment in twelve out of thirty‐nine (30%) of controls and twelve out of forty (31%) of the treated group. There was a significant increase in the number of patients with specific IgG antibody after injections of D. pteronyssinus extract as compared with the controls. This increase was associated with clinical improvement which occurred mainly in subjects who showed a decrease, little change or an increase of less than 30% in specific IgE antibody. In those with an increase of more than 30% in specific IgE antibody there was no evidence of clinical improvement even if specific IgG was produced. Diminished release of histamine from leucocytes was found after treatment in six out of ten treated compared with three out of eleven controls. There were, however, no differences between treatment and control groups in lymphocyte transformation and the liberation of leucocyte inhibitory agents. Clinical improvement was significantly better in those treated patients who gave strong nasal and skin reactions before treatment than in those with weak nasal and skin reactivity, who were no different from the controls.

No abstract

Summary Tests of the sera of fifty‐eight bird fanciers, comprising eighteen pigeon faticiers, thirty‐five budgerigar fanciers and five exposed to other birds, against the sera of the pigeon, budgerigar, hen, turkey, pheasant, canary and finch, showed the presence in the avian sera of antigenically related serum albumin and some β‐globulin components. Pigeon serum macro‐ and γ‐globulin components reacted specifically only with the pigeon faticiers'sera, and budgerigar γ‐globulin and a β‐globulin Bβ2G reacted specifically only with budgerigar fanciers'sera. The pigeon fanciers'sera contained the largest amounts of precipitating and haemagglutinating antibody. Avian serum proteins are present in bird droppings, so that the common antigens may cause reactions in affected subjects on exposure to the droppings dust of different birds. The patients'sera may also be useful for characterization of the avian serum proteins.