title: Increased activation-induced cell death in peripheral lymphocytes of rheumatoid arthritis patients: the mechanism of action.
abstract: Recently, we have described a soluble survival signal for activated lymphocytes from CD14(+) cells. As a result of the importance of T lymphocytes in the pathogenesis of rheumatoid arthritis (RA), we speculate a possible role for CD14(+) cells in supporting the outgrowth of autoreactive lymphocytes in RA. To address this issue further, supernatants from activated CD14(+) cells (CD14 cocktails) in both normal controls and RA patients were collected. The relative strength of the CD14 cocktails from normal controls and RA patients was compared. The data showed that depletion of CD14(+) cells resulted in a much higher increase of activation-induced cell death (AICD) and a decrease of lymphocyte proliferation in the peripheral blood mononuclear cells of RA patients compared to normal controls. Interestingly, CD14 cocktails from RA patients provide much stronger protection against AICD compared to those from normal controls. The observed soluble survival signal from CD14(+) cells is a general phenomenon because CD14 cocktails prevent both phytohaemagglutinin A-p- and anti-CD3-induced AICD. Furthermore, supernatants collected from human dendritic cell cultures also prevent activated lymphocytes from undergoing AICD. The data implicate an important role of the CD14(+) cell and its secreted form of survival signal in the pathogenesis of RA.
authors.affiliation: The Department of Microbiology and Immunology, the Arizona Arthritis Center, the University of Arizona, Tucson, AZ 85721, USA. charles.x.l.tang@cheerful.com
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Tang
authors.forename: David E
authors.initials: DE
authors.lastname: Yocum
authors.forename: David
authors.initials: D
authors.lastname: Dejonghe
authors.forename: Kathryn
authors.initials: K
authors.lastname: Nordensson
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Lake
authors.forename: John
authors.initials: J
authors.lastname: Richard
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D016022:Case-Control Studies; D016923:Cell Death; D002478:Cells, Cultured; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology; D018950:Lipopolysaccharide Receptors / Q000276:immunology*; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000276:immunology / Q000473:pathology*; D008875:Middle Aged; D018709:Statistics, Nonparametric; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D001324:Autoantigens; D007376:Interleukin-2; D018950:Lipopolysaccharide Receptors