Table 3.
Innate and pro-inflammatory cytokine profiles by ELISA in sera of gnotobiotic 9-day-old pigs inoculated with virulent US PEDV strain PC21A or mock at post-inoculation hour (PIH) 16 when or shortly after vomiting was first detected.
| Group | Pig no. | Clinical signs | Histological characteristics | Innatea |
Pro-inflammatorya |
|||
|---|---|---|---|---|---|---|---|---|
| IFNα (pg/ml) | IL-22 (pg/ml) | TNFα (pg/ml) | IL-6 (pg/ml) | IL-12 (pg/ml) | ||||
| PEDV-infected |
1 |
None |
Enterocyte necrosis is in progress, with incomplete villous atrophy |
1 |
186 |
10 |
213 |
27 |
| 2 |
None |
14 |
155 |
14 |
331 |
41 |
||
|
3 |
Vomitingb |
Complete villous atrophy |
119b |
943 |
46 |
817 |
102 |
|
| Mean (SD)c |
45 (65) |
428 (446) |
23 (20) |
454 (320) |
57 (40) |
|||
| Mock-infected |
4 |
None |
None |
1 |
4 |
4 |
151 |
19 |
| 5 |
None |
None |
1 |
4 |
4 |
66 |
8 |
|
| 6 |
None |
None |
1 |
15 |
4 |
209 |
26 |
|
| Mean (SD)c |
1 (0) |
8 (6) |
4 (0) |
142 (72) |
18 (9) |
|||
The samples were tested in duplicate, and cytokine levels were expressed as the mean values. Detection limits of our ELISA were 1 pg/ml for IFNα and IL-12, 4 pg/ml for TNFα and IL-22, and 16 pg/ml for IL-6, respectively.
Bold fonts and numbers, pig 3 with vomiting at PIH 16 showed higher serum IFNα, TNFα, IL-6, IL-12, and IL-22 cytokine levels compared with the other infected Gn pigs 1 and 2 with no vomiting, or uninfected Gn pigs 4–6.
Since there were no or little standard deviations of mean values of some cytokines in mock-inoculated pigs and large standard deviations of mean values of most of the cytokines in infected pigs as well as too few animals in each group, statistical analysis was not conducted.