These include overrepresentation of clinically aggressive histologic types and frequent infection of Reed-Sternberg ( RS ) cells by Epstein-Barr virus ( EBV ) .
these include overrepresentation of clinically aggressive histologic types and frequent infection of reed-sternberg ( rs ) cells by epstein-barr virus ( ebv ) .
O O O O O O O O O O O O B-cell_line I-cell_line I-cell_line I-cell_line I-cell_line O B-virus I-virus O B-virus O O