Probiotic Ingestion and Isoagglutinin Titers

Summary

Background:

* Probiotics are oral food supplements containing live bacteria that may be beneficial to a person s digestion or general health. Probiotics are available as tablets, powder, or liquid supplements and are frequently used to supplement yogurt. They are available for purchase without prescription in most supermarkets.
* The bacteria in probiotic supplements commonly express sugar substances on their surface. These sugar substances are similar to group A and B blood group sugars, called antigens. These antigens determine a person s blood group. Researchers are studying the effect of probiotic supplements on the amount of blood group antibodies that are present in a person s blood.

Objectives:

* To determine whether taking oral probiotic supplements increases anti-A and anti-B isoagglutinins (antibodies that cause red blood cells to clump together) in healthy subjects.
* To study the frequency of these effects and determine whether there is a dose-response relationship with probiotics and isoagglutinin titers.

Eligibility:

* Healthy adults, 18 years or older, with type A, B, or O blood.
* Female participants need to have undergone menopause or have had a hysterectomy.
* Individuals are ineligible if they currently donate platelets; have a history of ulcerative colitis or Crohn s disease; have had major bowel surgery; are pregnant or capable of becoming pregnant; have a bleeding or clotting disorder; have a history of a blood disorder or immune deficiency; have a history of high-risk behaviors for exposure to HIV or hepatitis B or C; have diabetes; have received vaccinations in the past 2 months, with the exception of the flu vaccine; are currently taking immunosuppressive medications; are currently taking antibiotics; or have taken probiotic supplements within the last 12 months.

Design:

* Researchers will conduct the following tests throughout the 28-week study:

* Blood samples will be drawn every 2 weeks to measure the quantity of isoagglutinin titers.
* Depending on individual results, continued blood testing may be done every 3 months for 1 year, then every 6 to 12 months for up to 5 years.
* Study subjects will take a probiotic supplement at a dose of 1 to 3 caplets per day for 18 consecutive weeks according to the following schedule:

* During the first 6-week period, the subject will take one probiotic tablet daily.
* During the second 6-week period, the subject will take one probiotic tablet twice daily.
* During the third 6-week period, the subject will take one probiotic tablet three times daily.
* Control group subjects will be followed in a similar manner but will not take probiotic supplements.
* The outcome measure is the percent of probiotic ingestors (the study subjects) versus control group subjects who experience a fourfold or greater rise in isoagglutinin titer.
* Study subjects will receive the following financial compensation: $10 per blood sample, for a maximum of $240 if all 24 samples are collected; $100 after completing the first 6-week period; $150 after completing the second 6-week period; and $200 after completing the third 6-week period.
* Control subjects will receive $10 per blood sample, for a maximum of $150 if all 15 samples are collected.

Conditions

• Isoagglutinin-Mediated Hemolysis
• Probiotic Toxicity

Interventions

DIETARY_SUPPLEMENT

Probiotic Supplement

Sponsors & Collaborators

• National Institutes of Health Clinical Center (CC)

  lead NIH

Principal Investigators

• Susan F Leitman, M.D. · National Institutes of Health Clinical Center (CC)

Study Design

Allocation

NON_RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2009-04-28

Primary Completion

2011-04-06

Completion

2011-04-06

Countries

• United States

Study Locations