title: Presentation of cartilage proteoglycan to a T cell hybridoma derived from a mouse with proteoglycan-induced arthritis.
abstract: Immunization of BALB/c mice with human fetal cartilage proteoglycan (PG) produces progressive polyarthritis, and T cells play key roles in the development of the disease. To gain an understanding of how PG is presented to autoreactive T cells by synovial antigen-presenting cells (APC), we examined the abilities of various syngeneic APC in presenting PG to a specific T cell hybridoma 5/4E8, derived from a mouse with PG-induced arthritis. A20 B lymphoma cells and spleen cells were strong presenters of PG, but synoviocytes and P388D1 macrophages could only present PG effectively after stimulation with interferon-gamma (IFN-gamma). The IFN-gamma exerted its effect by up-regulating both MHC class II and intercellular adhesion molecule-1 (ICAM-1) expression by these cells as neutralizing antibodies to Ia, LFA-1 and ICAM-1 inhibited presentation. Our studies also showed that synoviocytes and spleen cells took up and processed PG more rapidly than the cell lines. Cysteine and serine protease-dependent antigen presentation of PG was blocked at 4 degrees C, 18 degrees C and by chloroquine treatment, indicating that presentation required active uptake and processing in an acidic compartment, probably in lysosomes. Also, keratan sulphate-depleted and cyanogen bromide (CNBr) and 2-nitro-5-thiocyanobenzoic acid (NTCB)-cleaved PG elicited stronger T cell responses, as they were more easily processed than the native molecule. Furthermore, CNBr-generated peptides were presented by fixed APC, indicating that core protein fragments of cartilage PG can be presented directly by APC in context with MHC class II molecules.
authors.affiliation: Department of Biochemistry, Rush Medical University at Rush-Presbyterian-St Luke's Medical Centre, Chicago, IL 60612, USA.
authors.forename: F R
authors.initials: FR
authors.lastname: Brennan
authors.forename: G
authors.initials: G
authors.lastname: Negroiu
authors.forename: E I
authors.initials: EI
authors.lastname: Buzás
authors.forename: C
authors.initials: C
authors.lastname: Fülöp
authors.forename: K
authors.initials: K
authors.lastname: Holló
authors.forename: K
authors.initials: K
authors.lastname: Mikecz
authors.forename: T T
authors.initials: TT
authors.lastname: Glant
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology*; D001168:Arthritis / Q000276:immunology*; D001692:Biological Transport; D002356:Cartilage / Q000276:immunology*; D002738:Chloroquine / Q000494:pharmacology; D006825:Hybridomas / Q000276:immunology; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007376:Interleukin-2 / Q000096:biosynthesis; D016169:Lymphocyte Function-Associated Antigen-1 / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011480:Protease Inhibitors / Q000494:pharmacology; D011509:Proteoglycans / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000276:immunology*; D013696:Temperature
chemical_list: D007376:Interleukin-2; D016169:Lymphocyte Function-Associated Antigen-1; D011480:Protease Inhibitors; D011509:Proteoglycans; D018799:Intercellular Adhesion Molecule-1; D002738:Chloroquine