In vitro cytokine production and proliferation of T cells from patients with anti-proteinase 3- and antimyeloperoxidase-associated vasculitis, in response to proteinase 3 and myeloperoxidase.
OBJECTIVE
To investigate in vitro proliferative responses of CD4+ T cells and generation of specific cytokines induced by stimulation of peripheral blood mononuclear cells (PBMCs) from patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis with the autoantigens proteinase 3 (PR3) and myeloperoxidase (MPO).


METHODS
PBMCs from vasculitis patients with PR3 ANCA or MPO ANCA and from healthy controls were stimulated for 7 days with PR3, MPO, or control stimuli. Proliferation of CD4+ T cells was assessed by flow cytometry, using the proliferation marker Ki-67. Levels of the pro-proliferative cytokines interleukin-2 (IL-2) and IL-6 and of the Th1 and Th2 cytokines interferon-gamma (IFN gamma) and IL-10 in culture supernatants were determined.


RESULTS
PR3 and MPO induced proliferative responses in CD4+ T cells from individual patients with ANCA-associated vasculitides and healthy controls in vitro. Neither PR3 nor MPO elicited significant IL-2 production. Levels of IL-6 were highest after stimulation with PR3 but low after stimulation with MPO, independent of study group. Stimulation with PR3, and to a lesser extent with MPO, induced a Th2 cytokine milieu, characterized by high production of IL-6 and IL-10 and low production of IFN gamma in patients and controls.


CONCLUSIONS
PR3 and MPO promote proliferation of CD4+ T cells from patients with ANCA-associated vasculitides, but also cross-stimulate T cells from healthy individuals. Strong IL-10 production elicited by PR3 in vitro may act as an inhibitory signal for T cell proliferation and may have an important immunoregulatory function in vivo.
Popa
E R
ER
Department of Clinical Immunology, University Hospital Groningen, Groningen, The Netherlands. E.Popa@med.rug.nl
Franssen
C F M
CF
Limburg
P C
PC
Huitema
M G
MG
Kallenberg
C G M
CG
Tervaert
J W Cohen
JW
D000328:Adult; D000368:Aged; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D051792:Basic Helix-Loop-Helix Proteins; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology*; D002455:Cell Division / Q000187:drug effects*; D016207:Cytokines / Q000096:biosynthesis*; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D053146:Myeloblastin; D009195:Peroxidase / Q000276:immunology*; D012697:Serine Endopeptidases / Q000276:immunology*; D014157:Transcription Factors / Q000096:biosynthesis; D018366:Vasculitis, Leukocytoclastic, Cutaneous / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
D019268:Antibodies, Antineutrophil Cytoplasmic; D001324:Autoantigens; D051792:Basic Helix-Loop-Helix Proteins; D016207:Cytokines; D004268:DNA-Binding Proteins; D007371:Interferon-gamma; D016753:Interleukin-10; D007376:Interleukin-2; D015850:Interleukin-6; D053146:Myeloblastin; D009195:Peroxidase; D012697:Serine Endopeptidases; D014157:Transcription Factors; C095572:Hand1 protein, mouse