ESL ( + ) A 2 and ESL( - ) B 5 cells had the relatively stronger LIF mRNA or antisense LIF RNA expression, and LIF overexpression in ESL( + )A 2 cells was shown by biological assay for ES cell differentiation inhibition.

• 形态学观察发现,体外悬滴培养中经10~(-6)mol/L RA诱导后,过度表达LIF并未产生抑制ESL(+)A2细胞分化的现象,和亲本ES-5细胞比较,也未发现其明显改变了10~(-6)mol/L RA对ESL(+)A2细胞诱导分化的方向;