Diminished suppressor cell function in patients with asbestosis.

Epidemiological and immunological studies of asbestos workers documented abnormalities in humoral and cell-mediated immunity which could result from defective immunoregulation. This study tests this hypothesis with comparison of lymphocyte function in age-, sex- and smoking-matched subjects with asbestosis. In vivo measure of delayed hypersensitivity (i.e. skin test response) was significantly depressed to two recall antigens, SKSD and Candida, in asbestosis patients. Skin reaction to dinitrochlorobenzene (DNCB) was not depressed, although lymphocytes of patients giving positive skin test reactions demonstrated a significantly lower (P less than 0.001) proliferative response to dinitrobenzene sulphonic acid (DNBSO3) in vitro. T cell counts (E-rosettes) were normal in patients with asbestosis, although a subset of T cells, those forming sheep erythrocyte rosettes after prolonged incubation (Elate), were significantly depressed (P less than 0.003). This population has been equated with 'suppressor' cells (Grossi et al., 1978). Numbers of B cells were increased nearly two-fold over controls. Mitogen response of lymphocytes was normal except at suboptimal doses of mitogens where the response is known to be influenced by suppressor cell activity, which was significantly elevated. Suppressor cell function, as determined by stimulation of peripheral blood lymphocytes preincubated with concanavalin A, was also significantly decreased in asbestosis patients (P less than 0.01).

Aerosol bronchodilator therapy: a comparison of the effects of bronkometer with isoetharine, isoproterenol and phenylephrine.

The bronchodilator action and cardiovascular toxicity of aerosols of (1) isoetharine, (2) isoetharine in combination with phenylephrine, (3) isoproterenol, and (4) phenylephrine were compared in a group of severe stable ambulatory asthmatics. All preparations except phenylephrine produced reduction in specific airway resistance and increased flow rates which peaked at 15 minutes. The action of isoproterenol and the two isoetharine preparations peaked at 15 minutes while the peak effect of isoetharine and isoetharine in combination with phenylephrine continued for 60 minutes. The difference between isoproterenol and isoetharine alone or in combination with phenylephrine was not statistically significant. None of the drugs produced any cardiovascular side effects. The authors conclude that isoetharine, though less potent than isoproterenol on a weight-for-weight basis, is an effective and safe bronchodilator. Addition of phenylephrine to isoetharine does not potentiate or prolong the action of the latter.

A comparison of the prevalence of sensitization to Aspergillus antigens among asthmatics in Cleveland and London.

A survey of the frequency of sensitization to Aspergillus antigens was conducted in a group of asthmatics in Cleveland and compared with a group of asthmatics in London, using common antigens for testing purposes. The two groups were comparable except for earlier onset, longer duration of asthma, and a larger number of males in the London group. Twenty-eight per cent of the asthmatics from Cleveland and 23% from London had immediate skin reactivity to Aspergillus. Seven and one-half percent from the Cleveland group and 10.5% of the London group had Aspergillus precipitins in the serum. Aspergillus skin test reactivity was related to the severity of airways obstruction (p less than 0.01) but was not influenced by other factors. We conclude that sensitization to Aspergillus antigens occur with equal frequency in both the United States and the United Kingdom.

Pulmonary injury following exposure to chlorine gas. Possible beneficial effects of steroid treatment.

Two sisters were exposed to chlorine gas in toxic quantities in the same room of their home during an industrial accident. One was hospitalized and treated with corticosteroids and oxygen therapy, while the other received evaluation in the emergency room, and brief oxygen therapy and was released without corticosteroid therapy. Pulmonary physiologic studies have been performed on both patients at intervals following the exposure. The treated patient was stable, with normal results on studies of pulmonary function at the end of two years, while the sibling not treated with corticosteroids had demonstrable abnormalities of gas exchange which persisted during 55 months of observation. This "natural experiment" gives evidence of prolonged detrimental effects of sublethal exposure to chlorine gas on human pulmonary function in some patients. The effect of the differences in treatment between the two siblings cannot be definitely assessed in this single situation.