HSP90AB1 and Alzheimer disease: In cultured primary human keratinocytes stimulated with proinflammatory cytokine combinations (TNF/IFNγ or TNF/IL-4), pharmacological blockade of Hsp90 with the small-molecule inhibitor RGRN - 305 led to a substantial downregulation of genes involved in both Th1 and Th2 immune responses, including proinflammatory cytokines (TNF, IL1B, IL6) and chemokines typically upregulated in AD (CCL17, CCL22, TSLP).