Figure 8.

MutuDC lines are competent for MHC-I- and MHC-II-restricted presentation to T cells, including cross-presentation, similarly to splenic CD8α cDC. Two independent MutuDC lines (n = 2 per line) were directly compared to purified splenic cDC subsets for their capacity to present antigen to T cells(A). Direct MHC-I-restricted antigen presentation: DC were loaded with SIINFEKL peptide at the indicated concentrations and co-cultured with OT-1-transgenic CD8 T cells. MHC-II-restricted antigen presentation: DC were incubated with Ova^323–339 peptide at the indicated concentrations and co-cultured with OT-2-transgenic CD4 T cells. MHC-I-restricted cross-presentation: DC were co-cultured with ovalbumin-coated splenocytes (OCS) at the indicated numbers and further co-cultured with OT-1-transgenic CD8 T cells. T cell proliferation was quantified at day 3. The experiments are described in detail in Section “Materials and Methods.” Data are presented as mean ± SD (B). Values of the best-fit slope comparing each DC type (“subject” column: MutuDC lines or splenic cDC subsets) to the splenic CD8α⁺ or CD8α⁻ cDC references (in columns, as indicated). The data from (A) were analyzed by performing non-linear fit regressions (with robust fit) as a measure of the relative magnitude of the response induced by different DC types. A best-fit slope of 1 means the subject (DC type, left column) and reference (“versus” columns: CD8α⁺ or CD8α⁻ cDC) are equally competent; >1 means the subject is more competent than the reference; <1 = subject is less competent than the reference.