Accession Number : ADA449199


Title :   Lactobacilli Activate Human Dendritic Cells that Skew T Cells Toward T Helper 1 Polarization


Corporate Author : ARMY MEDICAL RESEARCH INST OF INFECTIOUS DISEASES FORT DETRICK MD


Personal Author(s) : Mohamadzadeh, Mansour ; Olson, Scott ; Kalina, Warren V ; Ruthel, Gordon ; Demmin, Gretchen L ; Warfield, Kelly L ; Bavari, Sina ; Klaenhammer, Todd R


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/a449199.pdf


Report Date : 06 Jan 2005


Pagination or Media Count : 7


Abstract : Professional antigen-presenting dendritic cells (DCs) are critical in regulating T cell immune responses at both systemic and mucosal sites. Many Lactobacillus species are normal members of the human gut microflora and most are regarded as safe when administered as probiotics. Because DCs can naturally or therapeutically encounter lactobacilli, we investigated the effects of several well defined strains, representing three species of Lactobacillus on human myeloid DCs (MDCs) and found that they modulated the phenotype and functions of human MDCs. Lactobacillus-exposed MDCs up-regulated HLA-DR, CD83, CD40, CD80, and CD86 and secreted high levels of IL-12 and IL-18, but not IL-10. IL-12 was sustained in MDCs exposed to all three Lactobacillus species in the presence of LPS from Escherichia coli, whereas LPS-induced IL-10 was greatly inhibited. MDCs activated with lactobacilli clearly skewed CD4(+) and CD8(+) T cells to T helper 1 and Tc1 polarization, as evidenced by secretion of IFN-gamma, but not IL-4 or IL-13. These results emphasize a potentially important role for lactobacilli in modulating immunological functions of DCs and suggest that certain strains could be particularly advantageous as vaccine adjuvants, by promoting DCs to regulate T cell responses toward T helper 1 and Tc1 pathways.


Descriptors :   *POLARIZATION , *ESCHERICHIA COLI , *T LYMPHOCYTES , *CELLS(BIOLOGY) , *LACTOBACILLUS , *VACCINES , *SKEWNESS , FUNCTIONS , RESPONSE(BIOLOGY) , MYELOMA , MUCOUS MEMBRANES , ANTIGENS , IMMUNITY , MODULATION , IMMUNOLOGY , HUMANS , REPRINTS


Subject Categories : Biochemistry
      Medicine and Medical Research
      Microbiology


Distribution Statement : APPROVED FOR PUBLIC RELEASE