GRIA4 and Alzheimer disease: In parallel with GluA4 and Loricrin, we also examined expression of TSLP, a cytokine implicated in AD.15,50 In both forearm and back skin epidermis of healthy skin, TSLP-IL expression coincided with GluA4-IL, with a similar expression gradient increasing from deep to superficial, with peak intensity in SG (Figs. 4A, 5A, B, D).