Fig. 6.

Relationship between TNF-alpha, GM-CSF, and G-CSF mRNA expression and FIPV replication in macrophages. SPF-cat-derived alveolar macrophages (2 × 10⁶ cells) were cultured with medium alone, FIPV, or FIPV and MAb 6-4-2. The cells were collected at 0 h (as a control) and 72 h. The intracellular TNF-alpha, GM-CSF, and G-CSF mRNA expression levels were measured by RT-PCR. TNF-alpha, GM-CSF, and G-CSF mRNA were quantitatively analyzed in terms of the relative density value to mRNA for the housekeeping gene GAPDH. n = 6