The Epstein-Barr virus ( EBV ) nuclear antigen 2 ( EBNA-2 ) protein is essential for the immortalization of human primary B cells by EBV .
the epstein-barr virus ( ebv ) nuclear antigen 2 ( ebna-2 ) protein is essential for the immortalization of human primary b cells by ebv .
O B-virus I-virus O B-virus O O O O O B-protein_molecule O O O O O O O O B-cell_type I-cell_type I-cell_type I-cell_type O B-virus O