However, CD4+ T cells recognizing epitopes derived from unmodified apolipoprotein B100 (ApoB) has also been found, first in human ApoB100 transgenic mice [22], and more recently in the blood from subjects with and without atherosclerosis, by using an MHC class II-tetramer loaded with an ApoB epitope [23]. The gene discussed is CD4; the disease is atherosclerosis.