Abstract: Some biological charateristics(proliferation response, cytotoxicity,phenotype)of PHA-LAKcells under different preming and cultivating conditions were studied. The proliferation responses showed that the number of PHA-LAKcells after co priming for 48 h with PHA/rIL-2 declined dramatically during the first two days, and reached the peak value of proliferation on the same day(day 6 after priming)as did those PHA-LAKcells primed with PHAalone under the same cultivating condition, and the differences in the peak value and multiplication fold on every same day between the PHApreming alone and the PHA-LAKco priming group were statistically insignificant(P>0.05). The cytotoxicity results showed that the peak time of cytotoxicity of PHA-LAKcells co primed with PHA/rIL-2 against K₅₆₂ and Raji cell reached on day 6 after co priming, two days earlier than that of PHA-LAKcells premied with PHAalone and the peak value of the former against Raji cells was higher than that of the latter(P<0.01). The phenotype analysis showed that about 0.60～0.77 of PHA-LAKcells were CD3⁺ cells under different priming and cultivating condition, and CD3⁺,CD8⁺ cells of PHA-LAKprimed with PHA/rIL-2 were more than those of PHA-LAKprimed with PHAalone(P<0.05).

Key words: PHA-LAK cells, proliferation, cytotoxicity, phenotype