title: Mycobacterium bovis bacille Calmette-Guerin vaccination of cattle: activation of bovine CD4+ and gamma delta TCR+ cells and modulation by 1,25-dihydroxyvitamin D3.
abstract: METHODS
  1,25-dihydroxyvitamin D3 (1,25(OH)(2)D(3)) is a potent modulator of immune responses and may be beneficial in the treatment of tuberculosis. Recent evidence suggest that 1,25(OH)(2)D(3) may affect T-dependent responses in cattle; however, mechanisms by which this vitamin modulates activation of bovine T cells are unclear.
  
  
  OBJECTIVE
  Determine the effects of 1,25(OH)(2)D(3) on the expression of CD25, CD44, and CD62L by bovine T cell subsets proliferating in response to antigen stimulation.
  
  
  METHODS
  Antigen-specific recall responses of Mycobacterium bovis bacille Calmette-Guerin (BCG) vaccinated cattle were used as a model system to evaluate effects of 1,25(OH)(2)D(3) on the proliferation and activation of bovine T cell subsets.
  
  
  RESULTS
  CD4(+) and gamma delta TCR(+) cells were the predominant T cell subsets responding to soluble crude M. bovis-derived antigens (i.e., purified protein derivative and a BCG whole cell sonicate) by proliferation and activation-induced alterations in phenotype. These subsets exhibited increased CD25 and CD44 mean fluorescence intensity (mfi) and decreased CD62L mfi upon antigen stimulation. Addition of 1,25(OH)(2)D(3) inhibited proliferation of CD4(+) cells and decreased the expression of CD44 on responding (i.e., proliferating) CD4(+) and gamma delta TCR(+) cells.
  
  
  CONCLUSIONS
  These findings suggest that the production of 1,25(OH)(2)D(3) by macrophages within tuberculous lesions would inhibit proliferation and CD44 expression by co-localized CD4(+) and gamma delta TCR(+) cells.
authors.affiliation: US Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Bacterial Diseases of Livestock Research Unit, P.O. Box 70, Ames, IA 50010, USA. rwaters@nadc.ars.usda.gov
authors.forename: W R
authors.initials: WR
authors.lastname: Waters
authors.forename: B J
authors.initials: BJ
authors.lastname: Nonnecke
authors.forename: M R
authors.initials: MR
authors.lastname: Foote
authors.forename: A C
authors.initials: AC
authors.lastname: Maue
authors.forename: T E
authors.initials: TE
authors.lastname: Rahner
authors.forename: M V
authors.initials: MV
authors.lastname: Palmer
authors.forename: D L
authors.initials: DL
authors.lastname: Whipple
authors.forename: R L
authors.initials: RL
authors.lastname: Horst
authors.forename: D M
authors.initials: DM
authors.lastname: Estes
mesh_terms: D000818:Animals; D001500:BCG Vaccine / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002117:Calcitriol / Q000494:pharmacology*; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018960:Hyaluronan Receptors / Q000378:metabolism; D019041:L-Selectin / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D014380:Tuberculosis, Bovine / Q000276:immunology*; D014611:Vaccination
chemical_list: D001500:BCG Vaccine; D018960:Hyaluronan Receptors; D016692:Receptors, Antigen, T-Cell, gamma-delta; D015375:Receptors, Interleukin-2; D019041:L-Selectin; D002117:Calcitriol