tokens: However , its activity becomes lower in the double-positive and a fraction of the CD4+ CD8int/- cell population , indicating that an additional enhancer , located in either the first or the third intron of the CD4 gene , is required for CD4 gene expression in this population .
folded_tokens: however , its activity becomes lower in the double-positive and a fraction of the cd4+ cd8int/- cell population , indicating that an additional enhancer , located in either the first or the third intron of the cd4 gene , is required for cd4 gene expression in this population .
labels: O O O O O O O O O O O O O O B-cell_type I-cell_type I-cell_type I-cell_type O O O O O O O O O O O O O O O O O O B-DNA_domain_or_region I-DNA_domain_or_region O O O O B-DNA_domain_or_region I-DNA_domain_or_region O O O O O