title: Systemic immune responses in Alzheimer's disease: in vitro mononuclear cell activation and cytokine production.
abstract: To investigate the systemic signs of immune-inflammatory responses in Alzheimer's disease (AD), in the present study we have analyzed blood lymphocyte subsets and the expression of activation markers on peripheral blood mononuclear cells (PBMCs) from AD patients and age-matched healthy controls (HC) activated in vitro by recombinant amyloid-beta peptide (rAbeta42). Our study of AD lymphocyte subpopulations confirms the already described decrease of the absolute number and percentage of B cells when compared to HC lymphocytes, whereas the other subsets are not significantly different in patients and controls. We report the increased expression of the activation marker CD69 and of the chemokine receptors CCR2 and CCR5 on T cells but no changes of CD25 after activation. B cells are also activated by rAbeta42 as demonstrated by the enhanced expression of CCR5. Moreover, rAbeta42 induces an increased expression of the scavenger receptor CD36 on monocytes. Some activation markers and chemokine receptors are overexpressed in unstimulated AD cells when compared to controls. This is evidence of the pro-inflammatory status of AD. Stimulation by rAbeta42 also induces the production of the pro-inflammatory cytokines IL-1beta, IL-6, IFN-gamma, and TNF-alpha, and of the anti-inflammatory cytokines IL-10 and IL-1Ra. The chemokines RANTES, MIP-1beta, and eotaxin as well as some growth factors (GM-CSF, G-CSF) are also overproduced by AD-derived PBMC activated by rAbeta42. These results support the involvement of systemic immunity in AD patients. However, our study is an observational one so we cannot draw a conclusion about its contribution to the pathophysiology of the disease.
authors.affiliation: Dipartimento di Biopatologia e Biotecnologie Mediche e Forensi, Università di Palermo, Palermo, Italy.
authors.forename: Mariavaleria
authors.initials: M
authors.lastname: Pellicanò
authors.forename: Matteo
authors.initials: M
authors.lastname: Bulati
authors.forename: Silvio
authors.initials: S
authors.lastname: Buffa
authors.forename: Mario
authors.initials: M
authors.lastname: Barbagallo
authors.forename: Anna
authors.initials: A
authors.lastname: Di Prima
authors.forename: Gabriella
authors.initials: G
authors.lastname: Misiano
authors.forename: Pasquale
authors.initials: P
authors.lastname: Picone
authors.forename: Marta
authors.initials: M
authors.lastname: Di Carlo
authors.forename: Domenico
authors.initials: D
authors.lastname: Nuzzo
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Candore
authors.forename: Sonya
authors.initials: S
authors.lastname: Vasto
authors.forename: Domenico
authors.initials: D
authors.lastname: Lio
authors.forename: Calogero
authors.initials: C
authors.lastname: Caruso
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Colonna-Romano
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000276:immunology* / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000494:pharmacology; D000704:Analysis of Variance; D016022:Case-Control Studies; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000494:pharmacology; D013997:Time Factors
chemical_list: D016229:Amyloid beta-Peptides; D016207:Cytokines; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)