Intestinal TTFC-specific immunoglobulinAwas induced only
after immunization with the recombinant L. plantarum mutant
strain. This conclusion, however, was not unequivocal because
the gene encoding TTFC was expressed in the LAB
carriers from promoters that are difficult to compare (a nisininducible
promoter and a constitutive promoter) (Grangette
et al. 2004)