Immunological responses to monoassociated Bifidobacterium longum and their relation to prevention of bacterial invasion

Immunology. 1985 Sep;56(1):43-50.


After monoassociation of Bifidobacterium longum with germ-free BALB/c mice (nu/+, heterozygous to nu gene), B. longum was recovered (10(2)-10(4) viable units per organ) from the mesenteric lymph nodes, liver and kidneys for 2 weeks post intragastric inoculation, but not after 4 weeks and later. Cessation of bacterial translocation was not observed in monoassociated nude (nu/nu) mice. Anti-B. longum IgA antibody was detected by ELISA using B. longum cell wall antigen in bile from Week 1 and in ileac wall extract from Week 8 post-association in both nu/+ and nu/nu mice. Total IgA levels in bile, ileac wall extract and caecal contents were also elevated in both mice after monoassociation. Cell-mediated immunity measured by the footpad test and macrophage migration inhibition test using B. longum protein fraction was detected in nu/+ mice in Week 4 and later, but not in nu/nu mice. Nu/nu mice reconstituted 4 weeks prior to monoassociation with lymphocytes from flora bearing nu/+ mice developed delayed footpad reactivity and bacterial translocation stopped after 4 weeks. Cell-mediated immunity rather than IgA antibody correlated well with the cessation of translocation.

MeSH terms

  • Actinomycetales Infections / immunology*
  • Actinomycetales Infections / microbiology
  • Actinomycetales Infections / prevention & control
  • Animals
  • Antibodies, Bacterial / analysis
  • Antigens, Bacterial / immunology*
  • Bifidobacterium / immunology*
  • Female
  • Germ-Free Life
  • Immunity, Cellular
  • Immunization, Passive
  • Immunoglobulin A / analysis
  • Immunoglobulin A, Secretory / analysis
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude


  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Immunoglobulin A
  • Immunoglobulin A, Secretory