Branchial challenge of normal subjects with the endotoxin of Enterobacter agglomerans isolated from cotton dust.

Abstract

Endotoxin produced by a culture of Enterobacter agglomerans isolated from cotton dust was inhaled by 12 normal subjects. No significant airway constriction was obtained in doses equivalent to those experienced in a workshift in a dusty mill. There was a statistically significant difference between this result and the bronchoconstriction that had occurred after flax dust inhalation in the same subjects. It is suggested that Enterobacter agglomerans endotoxin is not the causative agent of the acute bronchoconstriction that follows inhalation of textile dust.Neal et al reported that inhalation of a sterile filtrate of a culture of Aerobacter cloacae by a volunteer resulted in fever, dyspnoea, and coughing.' Pernis et al administered the endotoxin of Escherichia coli to three subjects and the endotoxin of Salmonella abortus equi to two of these subjects in doses of 15, 30, and 60 ug.2 Coughing, slight dyspnoea, and slight reduction in forced expiratory volume in one second (FEV,) were reported along with fever, malaise, and a skin reaction. Cavagna et al found that two out of eight normal subjects inhaling 80 pg of E coli endotoxin showed a fall in FEV, of more than 10%.3 Van der Zwan et al found a 14% fall in FEV, in subjects with bronchial hyperreactivity after inhaling 4mg endotoxin from Haemophilis influenza.4These experiments suggested that the bacterial endotoxin content of textile dusts may be the causative agent of the bronchoconstriction that is the response of normal subjects to these dusts. The effects were, however, not easily comparable with the equivalent dose of endotoxin in textile dusts. A further uncertainty is the evidence that endotoxins from different bacteria have differing biological activities.5 7We have reported the ventilatory responses of a panel of 12 normal subjects to flax dust when we found a 30% reduction in this response after steam Accepted 26 November 1985 treatment which also reduced the endotoxin content by 50%.8 It is therefore of interest to compare the response of this panel of subjects with the direct inhalation of the appropriate endotoxin in the equivalent dose. Cotton and other organic dusts commonly contain Enterobacter agglomerans9 and this has also been found in flax dust (B Buick, personal communication). We have challenged our panel of normal subjects with the endotoxin produced by this organism, isolated and purified by the technique of Helander et al,6 and given in a dose guided by Limulus assay of the endotoxin content of flax dust. Methods SUBJECTSThe same panel of 12 normal subjects who participated in the flax dust trial8 were studied. One subject was a smoker but did not smoke on trial days. The subjects gave informed consent and the experiments had the approval of the ethical committee. ENDOTOXINThe endotoxin was prepared in Helsinki by Helander et al.6 The organism Ent agglomerans was isolated and cultured from the cotton dust and the lipopolysaccharide extract prepared from the culture. The endotoxin was dissolved in 2 ml of saline and inhaled b...

<i>Pantoea agglomerans</i>: a marvelous bacterium of evil and good. Part I. Deleterious effects: Dust-borne endotoxins and allergens – focus on cotton dust

“…The threshold doses causing symptoms, standardized by the Limulus test, were equal to 30 µg of LPS-PW or 300 µg of CE-A. The results of this research explained the negative results obtained earlier by Jamison and Lowry [99] from the University of Belfast in Northern Ireland, who did not observe a drop in spirometric values and occurrence of symptoms in human volunteers exposed to P. agglomerans LPS-PW in the doses of 5 μg and 12 μg, which were simply too low to evoke any reaction (except for a significant drop in DLCO after exposure to 12 μg of LPS). This assessment was supported later by Thorn [100] who assumed that inhalation of 30-40 μg LPS seems to be a threshold level for inducing clinical symptoms and lung function changes in healthy human subjects.…”

“…This assessment was supported later by Thorn [100] who assumed that inhalation of 30-40 μg LPS seems to be a threshold level for inducing clinical symptoms and lung function changes in healthy human subjects. The British authors [99] used purified LPS (LPS-PW), which was less appropriate for the study of exposure effects than CE-A. In the conclusion of their work, Rylander et al [28] expressed an opinion that their results support the hypothesis that bacterial endotoxins cause mill fever, grain handler's fever and humidifier fever.…”

The inflammatory response in humans after inhalation of bacterial endotoxin: a review

“…Saline solution has generally been used as the solvent rather than distilled water since the latter may cause bronchoconstriction [36]. Most investigators have used LPS from Escherichia coli [19, 23-29, 32, 34], although some have obtained extracts of LPS from Enterobacter agglomerans [21,22] and Haemophilus influenzae [20]. To my knowledge, there are no published reports (with human subjects) of a comparison of the responses to endotoxin from different Gram-negative bacteria or the different methods of extraction.…”

“…The different doses of LPS used in the studies suggest a threshold level for inducing clinical symptoms after LPS inhalation of approximately 30 -40 mg [22,34], while 12 and 20 mg of inhaled LPS was not found to induce any symptoms [21,29]. Larsson et al [38] showed that symptoms such as fever and malaise were induced in normal subjects using an endotoxin concentration of 0.08 -1.3 mg/m 3 in airborne swine dust, which roughly corresponded to approximately 2.0 to 3.0 mg LPS.…”

“…Jamison and Lowry [21] challenged 12 normal subjects with an inhalation of LPS produced by Enterobacter agglomerans isolated from cotton dust. The subjects first inhaled five mg and in a further trial 12 mg of LPS.…”