Ignite Creation Date:
2024-05-06 @ 2:20 AM
Last Modification Date:
2024-10-26 @ 11:17 AM
Study NCT ID:
NCT02027610
Status:
COMPLETED
Last Update Posted:
2015-11-18
First Post:
2013-12-23
Brief Title:
Vitamin A Stool Microbiota and Vaccine Response in Bangladeshi Infants
Sponsor:
USDA Western Human Nutrition Research Center
Organization:
USDA Western Human Nutrition Research Center
Study Overview
Official Title:
Newborn Vitamin A Supplementation Gut Microbiota and Vaccine Response During the Second Year of Life in Bangladeshi Infants
Status:
COMPLETED
Status Verified Date:
2015-11
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Vitamin A deficiency VAD increases the risk of death from infections in infants and young children The World Health Organization WHO recommends high-dose vitamin A supplementation VAS from 6-59 months of age to reduce the risk of death in countries where VAD is common Such countries include Bangladesh where this study is being conducted While providing VAS at 6 months is recommended providing VAS at birth may also decrease the risk of death since newborn infants are also at risk of VAD VAS presumably reduces infant mortality by improving the immune response to infection and immunization Vitamin A particularly affects the development and function of T cells which develop in the thymus and are a key component of the memory response to infection and immunization Vitamin A is important for development of an important class of T cells regulatory T-cells in the intestine Regulatory T-cells prevent over-reaction of the immune system to substances the immune system might otherwise treat as harmful such as food or the healthy bacteria in the intestine VAD could disrupt the normal colonization of the infants intestinal tract and cause a condition called dysbiosis where abnormal bacteria flourish and adversely affect the infants immune system Dysbiosis may disrupt the immune response to injectable and oral vaccines VAS at birth may prevent dysbiosis and thus improve immune function response to vaccines and child survival The investigators recently completed an intervention trial in Bangladeshi infants NCT01583972 examining the effect of VAS at birth on immune function and response to vaccines administered from birth to 14 wk of age The present study will recruit infants who completed NCT01583972 when they are from 12 to 24 m of age to determine if VAS at birth affects the responses to these same vaccines when they are measured during the second year of life The investigators will examine the effect of VAS at birth on gut microbiota measured early in infancy and during the second year of life and explore the association of the gut microbiota with vaccine response Mothers of study infants will participate in the study because the breast milk oligosaccharide content strongly affects gut microbiota composition and the secretor status of the mother which can be determined from maternal FUT2 genotype strongly affects breast milk oligosaccharide content
Detailed Description:
Hypotheses and Specific Aims The investigators will test the hypotheses that VAS at birth will 1 improve production of new T cells at 1-2 yr of age 2 improve T-cell memory responses at 1-2 yr of age to vaccines given early in infancy birth - 14 wk and 3 alter intestinal colonization early in infancy 6 11 and 15 wk and at 1-2 yr of age to increase Bifidobacterium and other healthy bacteria and decrease Proteobacteria and other harmful bacteria Because the secretor status of the mother affects the carbohydrate content of the breastmilk which can in turn affect Bifidobacterium growth in the infant gut the secretor status of the mother will be determined Furthermore these differences in composition of the intestinal bacteria will be associated with greater immunologic responses to oral and systemic vaccines
Specific Aim 1 Determine if VAS or placebo at birth affect the blood concentration and thymic output of naïve T-cells at 1-2 yr of age Specific Aim 2 Determine if VAS or placebo at birth affect T-cell mediated responses at 1-2 yr of age to vaccines given early in infancy including serum and intestinal antibody levels vaccine-specific proliferative responses by T cells and cytokine production by T cells Specific Aim 3 Determine if VAS or placebo at birth affect the relative abundance of healthy intestinal bacteria and common harmful bacteria in the feces at 6 11 and 15 wk of age and at 1-2 yr of age and determine if relative abundance of these bacteria correlates with vaccine responses shortly after vaccination 6 11 15 wk and later in infancy 1-2 yr As part of Aim 3 the secretor status genotype FUT2 gene of the mother will be determined from a cheek swab DNA sample
Specific Aim 1 Determine if VAS or placebo at birth affect the blood concentration and thymic output of naïve T-cells at 1-2 yr of age Specific Aim 2 Determine if VAS or placebo at birth affect T-cell mediated responses at 1-2 yr of age to vaccines given early in infancy including serum and intestinal antibody levels vaccine-specific proliferative responses by T cells and cytokine production by T cells Specific Aim 3 Determine if VAS or placebo at birth affect the relative abundance of healthy intestinal bacteria and common harmful bacteria in the feces at 6 11 and 15 wk of age and at 1-2 yr of age and determine if relative abundance of these bacteria correlates with vaccine responses shortly after vaccination 6 11 15 wk and later in infancy 1-2 yr As part of Aim 3 the secretor status genotype FUT2 gene of the mother will be determined from a cheek swab DNA sample
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None