Figure 2.

DCs from P. yoelii-infected mice can process exogenous antigen for MHC class II presentation but not for MHC class I. (A,B) DCs pre-incubated with uninfected (black circles) or P. yoelii-infected (white circles) erythrocytes for 24 h, were incubated with OVA at the indicated concentrations for 5 h. DCs were then fixed and incubated with hybridoma B3Z specific for OVA epitope 257–264/H-2^b (MHC-I) (A) or hybridoma DO11.10 specific for OVA epitope 323–339/I-A^d (MHC-II) (B). (C,D) DCs were incubated with BSA (5 mg/ml; balck bars) as negative control or OVA (5 mg/ml; white bars) for 5 h before addition or not of LPS for 16 h. DCs were then incubated with B3Z (C) or DO11.10 (D) hybridomas for 24 h. (E-H) DCs alone, pre-incubated with uninfected or P. yoelii-infected erythrocytes (E,F) or CD11c⁺ DCs isolated from infected mice at different times during blood-stage infection (G,H) were incubated with OVA 5 mg/ml (white bars) or BSA 5 mg/ml as negative control (black bars) for 5 h before addition of LPS for 16 h. DCs were fixed and incubated with hybridoma B3Z (E,G) or hybridoma DO11.10 (F,H). After 24 h, secretion of IL-2 by hybridomas in the culture medium was detected by ELISA.