Table 2.

TNF-α (IU/ml)-like activity in cannulated, untreated (control) rats

Rat	Plasma alone	Plasma + NRS (1:100)	Plasma + anti-TNF-α (1:100)
1	291	356	<38
2	134	193	<38
3	206	243	<45
4	90	180	<63
5	<63	89	<63

Blood samples were collected from individual rats 48 h after insertion of jugular venous catheters, and plasma samples were incubated with L929 cells to determine TNF-α-like activity. Samples were incubated in the assay, either alone or in the presence of a 1:100 dilution of either normal rabbit serum (NRS) or rabbit anti-TNF-α. Results are expressed as international units per milliliter (IU/ml).