Optimizing NK-92 serial killers: gamma irradiation, CD95/Fas-ligation, and NK or LAK attack limit cytotoxic efficacy

Table 1 Compound effects of viable cell recovery and impaired lytic activity on NK-92 cell functionality one day after irradiation*

Irradiation (Grays)	% Control viable cell recovery⁺	Serial KF	% Control KF	% Remaining functional activity based on KF^#	LU₅₀ per 10⁶ NK-92 cells	% Control lytic units	% Remaining functional activity based on lytic units^{^}
0	100	5.6	100	100	815.5	100	100
2.5	53.4	3.9	69.6	37.2	419.8	51.5	27.5
5	56.8	2.5	44.6	25.4	215.9	26.5	15.0
10	39.0	1.5	26.8	10.4	23.8	2.9	1.1

*Raji 'target' cells at E:T 1:16 after 8 h. This representative experiment was comparable to two other replicate experiments
⁺Cells proliferated to increase 75–80% from time of initial culture without irradiation
^#Calculated as the fraction representing viable cell recovery multiplied by the fraction of control KF
^{^}Calculated as the fraction representing viable cell recovery multiplied by the fraction of lytic unit activity that was retained compared to untreated NK-92 cells

ISSN: 1479-5876