A Subset of Splenic Macrophages Process and Present Native Antigen to Naive Antigen-Specific CD4+T-Cells from Mice Transgenic for an αβ T-Cell Receptor

The progeny of individual macrophage precursors from mouse spleen were examined for their ability to constitutively process and present native pigeon cytochrome c or a peptide fragment of this antigen to naive CD4+T-cells from mice transgenic for a Vα11/Vβ3 TCR that recognizes an epitope in the antigen fragment. The results show that constitutive Ag processing and presentation is a stable characteristic restricted to the progeny of approximately 20% of splenic macrophage precursors. This property does not appear to be randomly acquired, but to reflect the ability of certain macrophages to produce IL-12.