title: Cholecystokinin octapeptide inhibits immunoglobulin G1 production of lipopolysaccharide-activated B cells.
abstract: Cholecystokinin octapeptide (CCK-8) is a typical brain-gut peptide that exerts a variety of physiological actions in both the peripheral and central nervous systems. Our laboratory has previously reported that CCK-8 produces immunoregulatory action through activating CCK receptor (CCK1R/CCK2R) expression on immune cell surfaces. In the present study, we investigated the effect of CCK-8 on immunoglobulin G1 (IgG1) production in lipopolysaccharide (LPS)-activated B cells in vitro. CCK-8 inhibited the proliferation and IgG1 mRNA expression of LPS-activated B cells and therefore inhibited IgG1 production. The mechanism may be associated with the regulation of CCK-8 on transcription factors Blimp1, Pax5, Xbp1 and Bcl6. CCK-8 inhibited the expression of Blimp1, while the effect on Pax5, Xbp1 and Bcl6 varied with time, suggesting that CCK-8 acted as a complex regulator of LPS-activated B cells. The inhibitory action of CCK-8 was mainly mediated through the CCK2R pathway. These studies indicate that CCK-8 attenuates humoral immune responses and acts as endogenous immune deactivators in autoimmune diseases.
authors.affiliation: Basic Medical College, Hebei Medical University, Shijiazhuang 050017, People's Republic of China.
authors.forename: Jing-Ge
authors.initials: JG
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Cong
authors.forename: Xian-Xian
authors.initials: XX
authors.lastname: Jia
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Qiao-Xia
authors.initials: QX
authors.lastname: Li
authors.forename: Chun-Ling
authors.initials: CL
authors.lastname: Ma
authors.forename: Yu
authors.initials: Y
authors.lastname: Feng
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D007074:Immunoglobulin G / Q000096:biosynthesis* / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors / Q000502:physiology; D012844:Sincalide / Q000494:pharmacology* / Q000502:physiology; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D011949:Receptors, Cholecystokinin; C440499:lipopolysaccharide, Escherichia coli O111 B4; D012844:Sincalide