There are 2 clinical trials
The purpose of this study is to determine whether a single oral dose of vitamin D given to infants prior to Bacille-Calmette-Guerin (BCG) vaccination will enhance the immune response to BCG vaccination.
The investigators will also determine whether specific host genetic variants including the Fok-I(rs2228570T/C), Bsm-I(rs1544410A/G), GC(rs2282679A/C), DHCR7(rs12785878G/T) and CYP2R1 (rs10741657A/G) polymorphisms affect baseline vitamin D levels and alter the response to vitamin D supplementation.. Bacille-Calmette-Guerin (BCG) vaccine efficacy.
The investigators will determine whether specific host genetic variants including the Fok-I(rs2228570T/C), Bsm-I(rs1544410A/G), GC(rs2282679A/C), DHCR7(rs12785878G/T) and CYP2R1 (rs10741657A/G) polymorphisms affect the response to BCG vaccine in infants receiving either vitamin D or placebo.. Inclusion Criteria: - Healthy mothers > 18 years of age - Term, healthy infants eligible to receive the Bacille-Calmette- Guerin (BCG) vaccine Exclusion Criteria: - Recent maternal history of tuberculosis (within 1 year) or active tuberculosis - Known maternal human immuno-deficiency virus (HIV) infection - Maternal fever or chorio-amnionitis - Maternal use of vitamin D, steroids or immuno-regulatory medications - Household member with active tuberculosis Inclusion Criteria: - Healthy mothers > 18 years of age - Term, healthy infants eligible to receive the Bacille-Calmette- Guerin (BCG) vaccine Exclusion Criteria: - Recent maternal history of tuberculosis (within 1 year) or active tuberculosis - Known maternal human immuno-deficiency virus (HIV) infection - Maternal fever or chorio-amnionitis - Maternal use of vitamin D, steroids or immuno-regulatory medications - Household member with active tuberculosis Tuberculosis Tuberculosis In 2000, there were an estimated 884,000 cases of tuberculosis (TB) in children with many developing severe, disseminated disease.
Description: BCG vaccine efficacy will be assessed by measuring the host immune response against BCG at 2 months, 6 months and one year after BCG immunization. A whole blood assay will be used to measure multiple cytokines and mycobacterial growth suppression.
Measure: Bacille-Calmette-Guerin (BCG) vaccine efficacy Time: 2 monthsDescription: Serum 25 hydroxy (OH) vitamin D levels will be measured prior to vitamin D supplementation and at 2 months, 6 months and one year after BCG immunization. The investigators will also determine whether specific host genetic variants including the Fok-I(rs2228570T/C), Bsm-I(rs1544410A/G), GC(rs2282679A/C), DHCR7(rs12785878G/T) and CYP2R1 (rs10741657A/G) polymorphisms affect baseline vitamin D levels and alter the response to vitamin D supplementation.
Measure: Effect of a single dose of 50,000 IU vitamin D3 on serum vitamin D levels Time: 2 monthsDescription: The investigators will determine whether specific host genetic variants including the Fok-I(rs2228570T/C), Bsm-I(rs1544410A/G), GC(rs2282679A/C), DHCR7(rs12785878G/T) and CYP2R1 (rs10741657A/G) polymorphisms affect the response to BCG vaccine in infants receiving either vitamin D or placebo.
Measure: Bacille-Calmette-Guerin (BCG) vaccine efficacy Time: 1 yearSkin pigmentation (melanin) absorbs ultra violet type B (UVB) radiation found in sunlight and is believed to be responsible for darker-skinned persons' generally low 25(OH)D status. This phenomenon is found in immigrants living in Northern countries and their 25(OH)D responses to UVB-irradiation seem low. We hypothesized that objectively measured skin pigmentation and/or pigment genes influence UVB-induced 25(OH)D increase significantly in combination with other influential parameters. The influence of objectively measured constitutive and facultative skin pigmentation on UVB-induced 25(OH)D increase over time was investigated together with other possible influential parameters. These other influential parameters include sex, age, weight, height, BMI, number of fatty fish meals per week, Fitzpatrick Skin Type and 25(OH)D start level. The genetic parameters include 33 Vitamin D receptor and pigment SNPs. This is a single-centre, open and non-blinded clinical trial. No randomisation was used, as the participants were allocated into two groups based on their Fitzpatrick Skin type and ethnic origin. The light-skinned group included participants with Fitzpatrick Skin type II-IV and were of Northern origin (Denmark, the Faroe Islands and the UK). The darker-skinned included Fitzpatrick Skin Types V-VI originating from countries located at latitudes below 50 degrees N. Thus, it could be ensured that the participants represented a wide range of skin pigmentation. The light-skinned (N = 22) and the darker-skinned subjects (N = 18) were exposed to identical UVB doses on identical body areas over nine weeks with weekly measurements of 25(OH)D. The UVB-induced 25(OH)D synthesis was investigated in summer-pigmented skin with melanin throughout the epidermis and during winter when ambient UVB exposure is negligible. Demographic data (gender, age, weight, height, Fitzpatrick Skin Type, measured constitutive and facultative skin pigmentation (PPF)) was collected/measured and registered in prior to study start. The number of daily consumed fatty fish meals was recorded in a questionnaire. Serum 25(OH)D was analysed weekly.
The influence of the vitamin D receptor gene was investigated by genotyping the two single nucleotide polymorphisms (SNP), rs1544410 (BsmI) and rs2228570 (FokI), located in the gene (ENSG00000111424, Chromosome 12q13) as previously described.
Description: Serum 25(OH)D is a marker of vitamin D increase induced by UVB
Measure: Change in serum 25(OH)D Time: Measured at study start and weekly over nine weeks