Threshold detection of self-antigen/MHC class II complexes formed in vivo: Constitutive presentation of an immunodominant epitope of hen egg lysozyme (HEL) in HEL-transgenic mice

Abstract

Hen egg lysozyme (HEL)-specific T hybridomas were used to study the presentation of HEL as a self component in tolerant, HEL-transgenic mice expressing different serum levels of HEL (AL3, 3-7 nM: ML5, 1-3 nM). Constitutive presentation of the HEL46-61 determinant was detectable in antigen presenting cell (APC)-enriched preparations of spleen, thymus, and lymph node from AL3 transgenic mice. The most likely cell responsible for constitutive presentation of HEL antigen was a non-B cell. In addition, constitutive presentation of HEL46-61 was clearly evident in thymic rosettes (complexes of macrophages or dendritic cells and lymphold cells) derived from AL3 HEL-transgenic mice, but not from ML5 ..