BCG vaccination of infants confers Mycobacterium tuberculosis
strain-specific immune responses to leucocytes
Abstract
The efficacy of bacille Calmette-Guerin (BCG) vaccination against
tuberculosis is highly variable, and protective immunity elicited by BCG
is poorly understood. We compared the cytokine/chemokine profiles of
peripheral blood mononuclear cells (PBMC) obtained from infants
BCG-vaccinated at birth and from non-vaccinated infants. The PBMC from
10-week old BCG-vaccinated infants released higher levels of
pro-inflammatory molecules than PBMCs from the non-vaccinated
counterpart. In vitro exposure of PBMCs from BCG-vaccinated infants, to
two different Mycobacterium tuberculosis strains, showed distinct pro-
and anti-inflammatory patterns. Thus, BCG-induced infant immune
responses and their protective ability may be shaped by the nature of
the infecting Mtb strain.