Tolerability and Clinical Outcome of Coseasonal Treatment with <b><i>Escherichia coli</i></b> Strain Nissle 1917 in Grass Pollen-Allergic Subjects

Abstract

Background: Nonpathogenic Escherichia coli strain Nissle 1917 (EcN) has immunomodulatory properties and can act on different cells which are important for the allergic immune response. Herein, we investigated the efficacy and tolerability of EcN in subjects with grass pollen-dependent allergic rhinoconjunctivitis. Methods: Grass pollen-allergic subjects were randomly allocated to receive EcN in a double-blind, placebo-controlled manner. The treatment was performed from 2 months before onset until the end of one grass pollen season (in total: 6 months). The clinical symptom score and the intake of symptomatic medications were assessed. A skin prick test and grass pollen-specific immunoglobulin (Ig) E and IgA were evaluated before and after treatment. Results: Our results show that coseasonal treatment with EcN in grass pollen-allergic subjects was not superior to placebo as assessed using the symptom-medication score (p = 0.257). Interestingly, an increase [median (range)] in grass pollen-specific IgA was detectable in the EcN group [20,556 LU/ml (1,812-60,800)] versus placebo [5,246 LU/ml (944-50,467)] (p = 0.048). Conclusions: The results indicate that 6 months of coseasonal nonspecific immunomodulation by EcN is not sufficient to achieve clinical efficacy in grass pollen-allergic subjects. Future approaches in which such immunomodulators are combined with an allergen-specific protocol might enhance the clinical efficacy of the allergen-specific treatment.

A systematic review and meta‐analysis of probiotics for the treatment of allergic rhinitis

“…The term “probiotic” is an all‐encompassing term, but the efficacy of particular formulations is largely dependent on geography, dietary practices, and prevailing gut microflora. This is echoed in the current study, with certain strains ( Lactobacillus paracasei 33) proving effective for treatment of grass pollen allergies, whereas others ( Escherichia coli strain Nissle 1917) proved ineffective . Similar differences in efficacy have been noted in other atopic diseases, with one probiotic strain proving effective for the treatment of atopic dermatitis in a comparative RCT, whereas another was completely ineffective …”

Insights from 100 years of research with probiotic E. coli

“…Less successful was an attempt to treat subjects with hay fever (grass pollen-allergic rhinoconjunctivitis). A randomized double-blind clinical trial with 6 months of treatment covering the full exposure season did not show effects on symptoms, pollen-specific humoral IgE or IgA levels, or a skin prick test [ 50 ]. Mutaflor was also not able to reduce carriage of multidrug-resistant E. coli in elderly residents of long-term care facilities [ 51 ], though, in this study, only two out of 12 treated subjects had detectable EcN in their feces.…”

Oral administration of Lactobacillus paracasei NCC 2461 for the modulation of grass pollen allergic rhinitis: a randomized, placebo‐controlled study during the pollen season

“…In our current in-season trial, exposure of each subject to grass pollen occurred in a natural and obviously non-controlled manner, and allergen doses might have varied considerably over time as well as within the whole study population. In addition to pollen counts, the country in which the study was performed, as well as other environmental factors such as climate and air pollution could also influence the results of a trial conducted during the pollen season [ 15 , 16 ].…”