Delayed-type hypersensitive (DTH) response was evaluated in C3H/HeJ mice in
testinally infected with Entamoeba histolytica. Infected and non-infected c
ontrol mice were challenged with amoebic antigen on day 5, 10, 15, 20, 25,
30, 40, 50, and 60 post-infection. Maximum footpad swelling was observed af
ter 24 hours of the challenge. The E. histolytica-infected mice exhibited a
DTH response on day 5, 15, 20, 25, 40, and 60 post-infection. However, on
day Ill, 30, and 50, such response was similar to that of the non-infected
control mice. The mice developed an evident DTH response late in the course
of infection (25 days post-infection). The infected mice did not show any
alteration to their DTH response against heterologous unrelated antigen (sh
eep red blood cells), suggesting that cellular anergy was antigen-specific.