Table 1.

Involvement of TNF-α in the suppressive activity of LNCi

CultureaProliferation (cpm)bNO production (μM)cIFN-γ production (U/ml)d
LNCn (WT)220,952 ± 1,7522.5 ± 14 ± 0.7
LNCn (TNF-α−/−)226,699 ± 3,1112.2 ± 0.83.1 ± 0.8
LNCn (WT) + LNCi (WT)831 ± 12144.5 ± 5.0511 ± 42
LNCn (WT) + LNCi (TNF-α−/−)203,378 ± 18,74031.5 ± 4.3138 ± 11
  • a LNC cultures at a concentration of 2 × 106/ml were stimulated with ConA. Cocultures of LNCn (2 × 106/ml) and LNCi (2 × 106/ml) were made in order to evaluate the suppressive activity of LNCi on the response of LNCn. The role of TNF-α in the suppressive activity was analyzed by using LNCi from wild-type (WT) mice as well as LNCi from TNF-α−/− mice.

  • b Proliferation of cell cultures was measured by [3H]thymidine incorporation after 48 h of incubation in the presence of ConA. Representative results are shown as mean cpm ± standard deviation.

  • c NO production was quantified by nitrite accumulation (Griess reaction) in the supernatants of cell cultures stimulated with ConA for 48 h. Results from triplicate measurements are shown as means ± standard deviations.

  • d IFN-γ production was quantified by specific ELISA (Pharmingen) in the supernatants of cell cultures stimulated with ConA for 48 h. Results from triplicate measurements are shown as means ± standard deviations.