CXCL8 and incontinentia pigmenti: Further support for the importance of IFNγ-triggered cytokine cascades in IP derives from the parallel elevations of IFNγ and IFNγ-inducible protein of 10 kDa (IP-10) along with the Th2 cytokine, IL-4, and the chemokine, IL-8 (Figure 6).