Fig. 3.

Binding assays of HLA I/HCMV-peptide-specific Fab tetramers to HCMV-infected fibroblasts. Tetramerized HCMV-specific Fab antibodies restricted to the HLA alleles A*0101, A*0201 and B*0702 show binding only to HCMV infected fibroblasts expressing the respective HLA allele and not to uninfected primary human skin fibroblasts (histograms on the left). All generated primary fibroblast cell cultures are shown in Table S4. A*0101: Both Fabs A6 and F3 show binding capacity to the HCMV infected primary fibroblast cells of Fibro2. As negative controls infected as well as uninfected fibroblasts were incubated with the Fabs C7 and 2A2 which are HCMV-specific but restricted to the HLA alleles B*0702 and B*0801 not expressed by Fibro2. A*0201: Tetramerized Fab C1 bound specifically to HCMV infected fibroblasts of Fibro5. As negative controls fibroblasts were incubated with the A*0101 and A*2402 restricted Fabs A6 and C12.2. B*0702: The C7 Fab tetramer and not the tetramers of C1 and C12.2, which are HCMV specific but restricted to the HLA I alleles A*0201 and A*2402, bound to the HCMV infected primary skin fibroblast cell culture Fibro4. None of the Fabs bound to uninfected fibroblasts of Fibro4