Keratinocyte-derived IL-1α regulates G-CSF production during OPC.

(A) Il1a and Il1b mRNA was quantified in the tongues of naïve (n) and infected (inf) WT mice by qRT-PCR 24 hours post-infection. (B–C) WT, Il1a^-/- and Il1b^-/- mice were infected with C. albicans. Csf3 mRNA levels in naïve and infected tongue tissue were determined by qRT-PCR (B), and G-CSF serum levels were measured by ELISA (C) before infection (open bars) and 24 hours post-infection (closed bars). (D) Immunofluorescent staining of sagittal tongue sections from naïve and infected WT and Il1a^-/- mice stained for IL-1α (yellow) and DAPI (blue) 24 hours post-infection. (E) Immunofluorescent staining of sagittal tongue sections from infected WT mice stained for keratin-6 (K6, left) or keratin-14 (K14, right) in red, as well as IL-1α (yellow) and DAPI (blue) 24 hours post-infection. Note that the IL-1α signal is absent in neutrophil-rich areas. The white arrow serves as orientation. (F) IL-1α and IL-1β mRNA expression in the tongues of naïve WT and infected WT, Il1a^-/- and Il1b^-/- mice was measured by qRT-PCR 24 hours post-infection. The detection limit, which was calculated using the average Ct (Actb) of all samples and Ct (Il1a) or Ct (Il1b) = 50, is depicted by a dotted line. Each symbol represents an individual mouse (A–B, F) and the lines represent the geometric mean of each group. The bar graph in C shows the group mean + SD. Data are representative of two independent experiments (A, D–E), or pooled from two independent experiments (B–C, F), with the exception of the naïve groups in C, which are the mean + SD of 4 (WT) or 3 (Il1a^-/-, Il1b^-/-) animals from one experiment. Statistical analysis was performed using log₁₀ transformation (A–B, F) and Student’s t-test with Welch’s correction (A), a one-way ANOVA with Dunnett’s test (B, F) or two-way ANOVA with Tukey’s test (C).