Effects of glucose-regulated protein94 (Grp94) on Ig secretion from human blood mononuclear cells

• DOI: 10.1007/s12192-010-0245-3
• Publication Date: 2010-11-30T19:55:57Z
• Authors: Elisa Tramentozzi; Rita Zamarchi; Andrea Pagetta; Anna Maria Brunati; Elisabetta Rossi; Elena Tibaldi; Paola Finotti
• Keywords: Adult; Male; 0303 health sciences; Membrane Glycoproteins; Time Factors; MAP Kinase Signaling System; Intracellular Space; Immunoglobulins; Middle Aged; Rats; Enzyme Activation; 03 medical and health sciences; Leukocytes, Mononuclear; Animals; Humans; Female; Extracellular Signal-Regulated MAP Kinases; Cell Shape; Heat-Shock Proteins; Cell Proliferation

Grp94 is the main endoplasmic reticulum-resident heat shock protein (HSP) that besides chaperoning native proteins, displays important modulatory effects on both innate and adaptive immune response. Since knowledge of a direct influence humoral response lacking, in this work we tested effect Ig secretion from peripheral blood mononuclear cells (PBMCs) five normal volunteers. The concentration secreted medium after incubation 15 days was found increased dose-dependent manner presence Grp94, used at final concentrations 10 100 ng/ml. However, by measuring different times, it apparent maximal percent stimulation occurred 7 days, decreasing thereafter. In addition, pattern time significantly differed with respect to control PBMCs. also stimulated PBMC proliferation, an preceded accompanied morphological changes similar those induced pokeweed mitogen. Effects PBMCs were mediated intense activation MEK-ERK1/2 pathway expression HSP90. Results indicate can activate cytokine-like, cell-mediated mechanism leads accelerated process B cell maturation differentiation.