For example, ER HSP90 homolog GRP94 plays important role in immunosuppressive activity of T regulatory cells, in lymphopoiesis of T and B cells, in production of proinflammatory cytokines by tumor-associated macrophages, in the regulation of platelet GPIbα subunit of GPIb-IX-V complex and maturation of dendritic cells (195, 201, 202, 226–231). The gene discussed is GP1BA; the disease is neoplasm.