Table 3.

Effects of Tonsil Cell Supernatants on Spontaneous Interleukin-8 Release by IPEC J2 Cells

Treatment	IL-8 (pg/mL±1 SD)
IPEC-J2 untreated cells	565±207
IPEC-J2 cells+tonsil cell supernatant	1055±338*
IPEC-J2 cells+tonsil cell supernatant+rIFN-α at 100 U/mL	820±244
IPEC-J2 cells+tonsil cell supernatant+rIFN-α at 1 U/mL	820±348

Pig tonsils were collected at the slaughterhouse. Viable tonsil mononuclear leukocytes of 5 healthy pigs were resuspended at 3 million mL^–1 and cultivated in RPMI 1640 medium+2-mercaptoethanol (5×10⁻⁴ M)+10% fetal calf serum. Tonsil cells were treated with rIFN-α at 0, 1, and 100 U/mL, and then incubated at 37°C in 5% CO₂. Supernatants were harvested 24 h later and stored under aseptic conditions in aliquots at −80°C. IPEC-J2 cells at confluence were washed once with MEM and treated with 1:4 diluted tonsil cell supernatants for 18 h at 37°C in 5% CO2. Supernatants were harvested 18 h later and stored under aseptic conditions in aliquots at −80°C for an IL-8 ELISA assay.

Results are shown in terms of pg/mL of IL-8±1 standard deviation in 5 tests. The asterisk indicates a significant difference with regard to untreated control cells (one-way ANOVA for repeated measures, P<0.05).

IL, interleukin.

^*P<0.05.