Efficacy of Newborn Vitamin A Supplementation in Improving Immune Function
|ClinicalTrials.gov Identifier: NCT01583972|
Recruitment Status : Completed
First Posted : April 24, 2012
Last Update Posted : August 26, 2014
|Condition or disease||Intervention/treatment|
|Vitamin A Deficiency||Dietary Supplement: retinyl palmitate Dietary Supplement: Placebo|
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||300 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)|
|Official Title:||Efficacy of Newborn Vitamin A Supplementation in Improving Immune Function|
|Study Start Date :||January 2012|
|Primary Completion Date :||July 2013|
|Study Completion Date :||August 2014|
Experimental: Vitamin A
50,000 IU vitamin A in edible oil
Dietary Supplement: retinyl palmitate
50,000 IU vitamin A in oil given within 48 h of birth from single-dose capsule
Other Name: Vitamin A
Placebo Comparator: Placebo
edible oil used as diluent for vitamin A
Dietary Supplement: Placebo
edible oil used as diluent for vitamin A given within 48 h of birth from single-dose capsule identical in appearance to vitamin A capsule
- Thymus size measured by ultrasound [ Time Frame: through 15 wk of age ]Thymus size will be assessed sonographically using a validated method in which the transverse diameter of the thymus and the sagittal area of its largest lobe are multiplied to give a volume-related thymic index (TI). This index has been shown to correlate with thymus weight and has been used to show that the human thymus is sensitive to environmental influences during infancy.
- peripheral blood naive T-helper lymphocyte concentration [ Time Frame: through 15 wk of age ]Naive and memory CD4 T lymphocytes will be measured by flow cytometric analysis using the CD45RA and CD45RO markers to identify naive and memory CD4+ T-cells, respectively. Naive T cells develop in the thymus and their level in peripheral blood is an index of thymic function.
- T-cell receptor excision circle (TREC) level in peripheral blood mononuclear cells (PBMC) [ Time Frame: through 15 wk of age ]Thymic T-cell production can be assessed by measuring signal-joint T cell receptor excision circles (TRECs) as a traceable molecular marker in newly produced naive T-cells. Thus, the content of TRECs in peripheral blood is an indicator of thymopoiesis or newly synthesized and exported naive T-cells. TREC assessment will be conducted in the stored peripheral blood mononuclear cells (PBMC) isolated from infant's blood by standard Ficoll density gradient methods.
- T-cell response to BCG (Bacillus Calmette-Guérin; to protect against tuberculosis) and oral polio virus (OPV) immunization [ Time Frame: through 15 wk of age ]The Flow-cytometric Assay of Specific Cell-mediated Immune response in Activated whole blood (FASCIA) will be used on peripheral blood mononuclear cells to determine the percentage of CD4+ T cells that that are responsive to the BCG and OPV vaccines given at birth (OPV is given again at 6, 10 and 14 wk of age). The BCG response will be elicited using purified protein derivative of M. tuberculosis and the OPV response using formalin-inactivated polio virus antigen (types 1, 2 and 3).
- Antibody response to oral polio virus (OPV) immunization [ Time Frame: through 15 wk of age ]The antibody in lymphocyte supernatant (ALS) assay will be used to assess the production of polio-specific antibody by peripheral blood mononuclear cells (PBMC) at 15 wk of age and the secretory IgA response to OPV will be assessed at 6, 11 and 15 wk of age by measuring antibody in stool
- T-cell and antibody response to tetanus toxoid (TT) and hepatitis B virus (HBV) vaccinations given at 6, 10 and 14 wk of age [ Time Frame: through 15 wk of age ]The Flow-cytometric Assay of Specific Cell-mediated Immune response in Activated whole blood (FASCIA) will be used to measure the T-cell response to TT and HBV immunization using these vaccine antigens to stimulate a response at 6 and 15 wk of age. The antibody in lymphocyte supernatant assay (ALS) will be used to measure the antibody responses to these vaccines at 15 wk of age.
- bacterial translocation to blood [ Time Frame: through 15 wk of age ]Bacterial lipopolysaccharide (LPS) concentrations will be measured in plasma as a marker of bacterial translocation.
- vitamin A status by modified, relative dose-response (MRDR) test [ Time Frame: through 15 wk of age ]vitamin A status will be measured using the MRDR in a subset of 30 subjects in each study arm.
- bulging fontanelle [ Time Frame: 48 h after vitamin A dosing ]The crainial fontanelle will be examined by study personnel to identify "bulging" as in indication of increased intracranial volume.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01583972
|International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b)|
|Principal Investigator:||Charles B. Stephensen, Ph.D.||USDA, Western Human Nutrition Research Center|