Localization of alpha/beta and gamma/delta T lymphocytes in Cryptosporidium parvum-infected tissues in naive and immune calves.
The nature of the host's T-lymphocyte population within the intestinal villi following Cryptosporidium parvum infection was characterized with a bovine model of cryptosporidiosis. In naive animals, infection with C. parvum resulted in substantial increases in the numbers of alpha/beta T cells, both CD4+ (150%) and CD8+ (60%), and of gamma/delta T cells (70%) present within the intestinal villi of the infected ileum. In immune animals, the host T-lymphocyte response to a challenge infection with C. parvum was restricted to alpha/beta T cells. The number of CD4+ T cells within the Peyer's patch of the ileum increased dramatically; however, there was little change in the number or localization of CD4+ T cells within the intestinal villi. In contrast, the number of CD8+ T cells within the intestinal villi increased following a challenge infection. In addition, the CD8+ T cells were found to be intimately associated with the epithelial cells of the intestinal villi. The precise correlation between the accumulation of CD8+ T cells and the normal site of parasite development suggests an important role for CD8+ T cells in the immune animal.
Abrahamsen
M S
MS
Department of Veterinary PathoBiology, University of Minnesota, St. Paul 55108, USA. abrah025@gold.tc.umn.edu
Lancto
C A
CA
Walcheck
B
B
Layton
W
W
Jutila
M A
MA
D000818:Animals; D002417:Cattle; D003457:Cryptosporidiosis / Q000276:immunology*; D016785:Cryptosporidium parvum; D007082:Ileum / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta