Immune System Stimulation by Probiotic Food Supplementation

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effects of a probiotic supplementation on adult volunteers with having caught the common cold more than 4 times in the past year. This study is a single center, double-blind, randomized, controlled, parallel-designed, prospective trial. Subjects received a probiotic drink containing probiotics of Lactobacillus paracasei (108 colony forming units (CFU)/ml), Lactobacilluscasei431® (108CFU/ml) and Lactobacillus fermentiumPCC® (106CFU/ml) or an identical placebo without probiotics for a 12-week study period. The incidence of flue and cold during the study period were compared between study groups. Blood and fecal samples were collected at baseline and at the end of the intervention. Fecal samples were collected for the secretory immunoglobulin A (sIgA) analysis. Blood sample was drawn for interferon γ (IFN-γ), interleukin 4 (IL-4), interleukin 10 (IL-10), immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) analysis.

Official Title
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Immune System Stimulation by Probiotic Food Supplementation: a Double-blind, Randomized, Controlled, Parallel-designed, Prospective Trial

Conditions
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Flu Symptom

Intervention / Treatment
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* Dietary Supplement: Weiquan Yogurt with probiotics
* Dietary Supplement: Weiquan Yogurt without probiotics


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: male or female between 25 to 45 years old; having caught the common cold or flu at least 4 to 6 times in the past calendar year; signed the informed consent forms before entering the study; fully understood the risks and potential benefits in participating this study. Exclusion Criteria: were diagnosed with the decreased immunity caused by any diagnosed chronic illness; having any gastrointestinal illness with medical treatment at the time of being enrolled; having any diagnosed respiratory illness with similar symptoms as the common cold and flu; currently taking any pain killer drug; having received any vaccine for the upper respiratory infection within 6 months before enrollment; having received any purgative drug or digestion related drug within 2 weeks before enrollment; having taken any dairy product containing prebiotics and probiotics within 10 days before enrollment; currently taking any preventive drug for upper respiratory infection; having received any drug which has impact with the immune system such as antibiotics within 3 months before enrollment; alcoholic or addicted to any drug; pregnant or breastfeeding mothers; having participated another clinical trial within 3 months before enrollment.

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Weiquan Yogurt with probiotics<br>Weiquan Yogurt with probiotics contained Lactobacillus paracasei (108 colony forming units (CFU)/ml), Lactobacillus casei 431® (108 CFU/ml) and Lactobacillus fermentum PCC® (106 CFU/ml) | Dietary Supplement: Weiquan Yogurt with probiotics<br>* 150 ml daily consumption for a total of 12 weeks<br>|
| Placebo Comparator: Weiquan Yogurt without probiotics<br>Weiquan Yogurt devoid of probiotics, but otherwise similar to the experimental product. | Dietary Supplement: Weiquan Yogurt without probiotics<br>* 150 ml daily consumption for a total of 12 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of flue symptoms during the study | Body temperature≥38.0℃, and have one or more symptoms of cough, runny nose, throat pain, headache, muscle pain, weak feeling, hard to breath, chest pain or loss of appetite. | end of week 12 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of cold symptoms during the study | Body temperature<38.0℃, and have one or more symptoms of cough, runny nose, throat pain, headache, muscle pain, weak feeling, hard to breath, chest pain or loss of appetite. | end of week 12 | 
| Number of accumulated days of having cold symptoms during the study | The total number of days of having one or more symptoms of cough, runny nose, throat pain, headache, muscle pain, weak feeling, hard to breath, chest pain or loss of appetite during the 12 week study period. | End of week 12 | 
| Serum IFN-γ concentration | Interferon gamma (unit: pg/ml) | Baseline, end of week 12 | 
| Serum IL-4 concentration | Interleukin 4 (unit: ng/ml) | Baseline, end of week 12 | 
| Serum IL-10 concentration | Interleukin 10 (unit: pg/ml) | Baseline, end of week 12 | 
| Serum IgA concentration | Immunoglobulin A (unit: g/L) | Baseline, end of week 12 | 
| Serum IgG concentration | Immunoglobulin G (unit: g/L) | Baseline, end of week 12 | 
| Serum IgM concentration | Immunoglobulin M (unit: g/L) | Baseline, end of week 12 | 
| Fecal sIgA concentration | Secretory Immunoglobulin A (unit: ng/ml) | Baseline, end of week 12 |