Anti–IFN-α Neutralizing Antibody Restores the Lymphocyte Proliferative Response to Mitogen and Recall Antigen
| . | IFN-α Neutralizing Antiserum . | Nonimmune Sheep Serum . | P Value . | ||||
|---|---|---|---|---|---|---|---|
| . | Mock CM . | CMV CM . | Inhibition (%) . | Mock CM . | CMV CM . | Inhibition (%) . | . |
| Mitogens (day 3) | |||||||
| Control medium | 1.2 ± 0.44-150 | 0.9 ± 0.44-150 | 1.7 ± 0.44-150 | 0.8 ± 0.24-150 | |||
| PHA | 155.4 ± 31.2 | 130.5 ± 23.0 | 14 ± 44-151 | 153.0 ± 27.2 | 112.8 ± 16.0 | 24 ± 54-151 | .039‡ |
| PWM | 28.6 ± 11.6 | 24.4 ± 8.6 | 12 ± 1 | 24.6 ± 7.8 | 19.0 ± 4.7 | 23 ± 7 | .073 |
| Recall antigen (day 6) | |||||||
| Control medium | 25.6 ± 7.5 | 11.0 ± 7.4 | 32.6 ± 0.4 | 6.8 ± 1.9 | |||
| TT | 48.8 ± 4.1 | 31.8 ± 5.8 | 35 ± 7 | 54.5 ± 8.6 | 16.8 ± 3.2 | 70 ± 2 | <.001 |
| . | IFN-α Neutralizing Antiserum . | Nonimmune Sheep Serum . | P Value . | ||||
|---|---|---|---|---|---|---|---|
| . | Mock CM . | CMV CM . | Inhibition (%) . | Mock CM . | CMV CM . | Inhibition (%) . | . |
| Mitogens (day 3) | |||||||
| Control medium | 1.2 ± 0.44-150 | 0.9 ± 0.44-150 | 1.7 ± 0.44-150 | 0.8 ± 0.24-150 | |||
| PHA | 155.4 ± 31.2 | 130.5 ± 23.0 | 14 ± 44-151 | 153.0 ± 27.2 | 112.8 ± 16.0 | 24 ± 54-151 | .039‡ |
| PWM | 28.6 ± 11.6 | 24.4 ± 8.6 | 12 ± 1 | 24.6 ± 7.8 | 19.0 ± 4.7 | 23 ± 7 | .073 |
| Recall antigen (day 6) | |||||||
| Control medium | 25.6 ± 7.5 | 11.0 ± 7.4 | 32.6 ± 0.4 | 6.8 ± 1.9 | |||
| TT | 48.8 ± 4.1 | 31.8 ± 5.8 | 35 ± 7 | 54.5 ± 8.6 | 16.8 ± 3.2 | 70 ± 2 | <.001 |
PBMC were incubated with cell-free inactivated HCMV or with the mock preparation in the absence or in the presence of anti–IFN-α neutralizing antibody or nonimmune sheep serum. Antibody was added at the beginning of the culture and after 6, 15, and 21 hours. The CM were obtained after 24 hours, treated to remove the virus, and then tested in the proliferative assay.
3H-thymidine incorporation assays are shown as the mean cpm/well ± SD multiplied per 103, obtained with 3 different PBMC cultures from CMV seronegative donors. Each assay was done in triplicate.
Percentage of inhibition = 100 minus (value obtained with CMV CM/its mock control multiplied by 100).
P value = one-tailed unpaired t-test, the proliferative responses obtained with CM from PBMC incubated with HCMV in the presence of anti-IFN-α neutralizing antibody was compared with the nonimmune sheep serum.