FIG. 7.

Neutralization assays confirm TNF-α and IFN-γ drive fractalkine induction in AEC. Neutralization carried out directly in cocultivations of CD4⁺ lymphocytes or PBMC with AEC. (A) Demonstration by ELISA screens of culture supernatants, showing loss of fractalkine in supernatants with neutralizing antibodies to target TNF-α and IFN-γ. In this sample, CD4⁺ cells were set up to scale with PBMC. Specific antibody blocks and controls are identified on the x axis as follows: No Ab, positive control with no antibody block; Iso, isotype control antibody; TNFa Ab block, antibody-treated sample to specifically neutralize TNF-α; IFNg Ab block, specific neutralization with IFN-γ antibody; Dual Ab block, combined anti-IFNγ and TNF-α antibodies; IL-12 Ab block, antibody to specifically neutralize IL-12. (B) In this sample, CD4⁺ cells are not set to scale but were loaded at ∼10⁶ cells per well, ∼4-fold above scale to the level of CD4⁺ cells in PBMC. Antibody blocks and controls are as described for panel A on the x axis; “Dual Ab block per day” refers to combined anti-IFN-γ and TNF-α antibodies added on each of the 3 days during cocultivation. The data are representative of three separate experiments with different donor samples.