Aspergillus fumigatus Crf1/p41-specific T-cell clones show highly specific cross-reactivity to C albicans and can be activated by different clinical isolates of both fungi. (A) All A fumigatus Crf1/p41-specific T-cell clones from different donors respond to stimulation with inactivated C albicans yeast (n = 3). Shown is 1 clone per antigen and donor. (B) Aspergillus fumigatus Crf1/p41-specific T-cell clones respond to different inactivated clinical isolates of germinating A fumigatus conidia and C albicans yeast (n = 3). (C) Aspergillus fumigatus Crf1/p41-specific T-cell clones from donors with different MHC class II restriction were stimulated with A fumigatus Crf1/p41 peptide, the homologous peptides of C albicans, A flavus, A nidulans, A terreus, and A niger (supplemental Figure 4B) or the unrelated peptides CMV pp65 KPG (KPGKISHIMLDVAFT) and A fumigatus Crf1/p1 and p59 (supplemental Table 1; representative experiments).