
Rottenberg ME, Bakhiet M, Olsson T, Kristensson K, Mak T, Wigzell H, Orn A:
Differential susceptibilities of mice genomically deleted of CD4 and
CD8 to infections with Trypanosoma cruzi or Trypanosoma brucei.
Infection & Immunity 1993 Dec;61(12):5129-33
ABSTRACT
The role of CD4+ and CD8+ T cells in the surveillance of Trypanosoma
cruzi or Trypanosoma brucei brucei was studied in mice which lacked
CD4 or CD8 molecules and which were generated by embryonic stem cell
technology. Whereas wild-type mice infected with T. cruzi (Tulahuen
strain) displayed low levels of parasitemia and no mortality,
striking increases in parasite growth and mortality occurred in both
CD8- and CD4- mice. On the contrary, CD8- and, to a lesser degree,
CD4- mice showed enhanced resistance to T. b. brucei.
T-cell-dependent immunoglobulin G-specific responses were produced
in CD8- but not CD4- mice. Normal T-cell proliferative responses
were measured in both CD4- and CD8- mice. Interleukin-4 production
after concanavalin A or anti-CD3 monoclonal antibody stimulation was
strikingly enhanced in CD8- but not CD4- spleen cells, whereas gamma
interferon production was normal in both CD4- and CD8- spleen cells.
Spleen and lymph node cells from CD8- (but not CD4-) mice at 20 days
postinfection with T. cruzi had higher levels of interleukin-4 mRNA
than the wild-type controls, as shown in a competitive polymerase
chain reaction assay. On the other hand, CD4- (but not CD8-) mice at
20 days postinfection with T. cruzi had lower levels of gamma
interferon mRNA than the wild-type mice.