TABLE 2.

Effects of PKA and PTK inhibitors on TNF-α induction and proliferation

Inhibitor	Enzyme target	TNF-α production (pg/ml)a	Proliferationb (%)
None (SEB alone)		2,377.6 ± 59.4	100
H1004	PKA	2,345.7 ± 18.0	Not determined
H89	PKA	2,379.0 ± 95.6	98.3 ± 4.1
Tyrophostin 23	PTK	2,479.0 ± 47.8	97.4 ± 3.3
AG1288	PTK	2,474.7 ± 69.6	101.7 ± 6.8
Genistein	PTK-PKC	1,357.6 ± 1.5c	53.4 ± 2.9d

^aFor TNF-α determinations, cells were plated in four replicates and incubated with inhibitors H89 (100 nM), HA1004 (20 μM), genistein (20 μM), tyrophostin 23 (20 μM), and AG1288 (20 μM) for 60 min followed by stimulation with 100 ng of SEB per ml for 20 h. Media were collected and analyzed in duplicate for TNF-α by using ELISA kits. 

^bFor proliferation, mixed cultures of monocytes and lymphocytes (1:4 ratio) were plated in replicates of six and incubated with the inhibitors as indicated above for 30 min prior to addition of SEB at 50 ng/ml (see Fig. 3B). Thymidine incorporation was determined as described in Materials and Methods. Lower concentrations of genistein did not show inhibition. 

^cStatistical analysis (t test) of significant differences compared to SEB alone showed P < 0.05. 

^dComparisons were made for each inhibitor with SEB alone, and significant differences were determined by analysis with Student's t test. Indicated values showed P < 0.0005.