Study of Probiotic Potential of Lactobacillus Strains in the Upper Respiratory Tract After Nasal Spray Application

Antwerp University Hospital (UZA)

Status: Unknown

Conditions: Healthy Volunteers; Nasal Disease; Sprays; Probiotics; Chronic Rhinosinusitis (Diagnosis)

Treatments: Other: Placebo nasal spray; Other: Probiotic nasal spray

Study type: Interventional

Funder types: Other

Identifiers

NCT03587545

B300201835709

Details and patient eligibility

About

Probiotics are defined as "live micro-organisms that, when administered in adequate amounts, confer a health benefit to the host" (Hill et al, 2014). These microbes are generally applied in the gastrointestinal tract via fermented food products or capsules. In previous research, the investigators isolated bacterial strains with potential probiotic properties for the upper respiratory tract based on in vitro laboratory tests, in vivo mice experiments and genome sequencing.

In this study, the investigators want to deliver the Proof-of-Concept that the most promising isolated strain, Lactobacillus casei AMBR2 (LAMBR2) and the well-documented probiotic strain Lactobacillus rhamnosus GG (LGG) also have interesting properties in humans, i.e. that these strains are able to -temporarily- persist in the upper respiratory tract of healthy volunteers and CRS patients after daily nasal application via a nasal spray for 2 weeks. In addition, the investigators aim to explore whether the application of these strains has an impact on the nasopharyngeal microbiome via 16S rRNA amplicon sequencing and dedicated qPCR analysis.

Therefore, bacterial DNA from nasal swabs will be isolated via commercially available DNA extraction kits, followed by Illumina MiSeq sequencing in order to identify the bacterial species present in these samples. Furthermore, the concentration of the Lactobacillus and specific pathogens will be monitored via qPCR.

Enrollment: 120 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• CRS patient group: CRS diagnosed

Exclusion criteria

• no patients with trisomy 21
• no pregnant women
• no breastfeeding women
• no acute or chronic airway infections (except for CRS patients in CRS patient group)
• no cancer
• no autoimmune diseases

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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120 participants in 6 patient groups, including a placebo group

Healthy probiotic group LGG

Experimental group

Description:

Daily intake by healthy volunteers of 2 dosages of LGG spray during 2 weeks. Probiotic nasal spray.

Treatment:

Other: Probiotic nasal spray

Healthy probiotic group LAMBR2

Experimental group

Description:

Daily intake by healthy volunteers of 2 dosages of LAMBR2 spray during 2 weeks. Probiotic nasal spray.

Treatment:

Other: Probiotic nasal spray

Healthy placebo group

Placebo Comparator group

Description:

Daily intake by healthy volunteers of 2 dosages of placebo spray during 2 weeks. Placebo nasal spray.

Treatment:

Other: Placebo nasal spray

CRS probiotic group LGG

Experimental group

Description:

Daily intake by CRS patients of 2 dosages of LGG spray during 2 weeks. Probiotic nasal spray.

Treatment:

Other: Probiotic nasal spray

CRS probiotic group LAMBR2

Experimental group

Description:

Daily intake by CRS patients of 2 dosages of LAMBR2 spray during 2 weeks. Probiotic nasal spray.

Treatment:

Other: Probiotic nasal spray

CRS placebo group

Placebo Comparator group

Description:

Daily intake by CRS patients of 2 dosages of placebo spray during 2 weeks. Placebo nasal spray.

Treatment:

Other: Placebo nasal spray