Does the immune system of milk increase activity for infants experiencing infectious disease episodes in Kilimanjaro, Tanzania?
Am J Hum Biol
; 35(8): e23897, 2023 08.
Article
in En
| MEDLINE
| ID: mdl-36951242
ABSTRACT
INTRODUCTION:
Multiple studies have reported that milk immune content increases for infants experiencing infectious disease (ID) episodes, suggesting that the immune system of milk (ISOM) offers enhanced protection when needed to combat ID.METHODS:
To test the hypothesis that ISOM content and/or activity increases during an infant's ID episode, we characterized milk secretory immunoglobulin A (sIgA; a major ISOM constituent) and in vitro interleukin-6 (IL-6) responses to Salmonella enterica and Escherichia coli, as system-level biomarkers of ISOM activity, in a prospective study among 96 mother-infant dyads in Kilimanjaro, Tanzania.RESULTS:
After control for covariates, no milk immune variables (sIgA, Coef 0.03; 95% CI -0.25, 0.32; in vitro IL-6 response to S. enterica, Coef 0.23; 95% CI -0.67, 1.13; IL-6 response to E. coli, Coef -0.11; 95% CI -0.98, 0.77) were associated with prevalent ID (diagnosed at the initial participation visit). Among infants experiencing an incident ID (diagnosed subsequent to the initial participation), milk immune content and responses were not substantially higher or lower than the initial visit (sIgA, N 61; p 0.788; IL-6 response to S. enterica, N 56; p 0.896; IL-6 response to E. coli, N 36; p 0.683); this was unchanged by exclusion of infants with ID at the time of initial participation.CONCLUSION:
These findings are not consistent with the hypothesis that milk delivers enhanced immune protection when infants experience ID. In environments with a high burden of ID, dynamism may be less valuable to maternal reproductive success than stability in the ISOM.
Full text:
1
Collection:
01-internacional
Health context:
2_ODS3
/
3_ND
Database:
MEDLINE
Main subject:
Salmonella Infections
/
Immunoglobulin A, Secretory
/
Interleukin-6
/
Salmonella enterica
/
Escherichia coli
/
Escherichia coli Infections
/
Milk, Human
Type of study:
Observational_studies
/
Risk_factors_studies
Limits:
Adult
/
Female
/
Humans
/
Infant
/
Newborn
Country/Region as subject:
Africa
Language:
En
Journal:
Am J Hum Biol
Year:
2023
Document type:
Article