Lymphocyte proliferative response to mitogenic monoclonal antibodies in systemic sclerosis. Evidence for unresponsiveness to murine monoclonal antibodies of IgG1 isotype.
Proliferative response of peripheral blood mononuclear cells to phitohemoagglutinin and anti-CD3 mitogenic monoclonal antibodies (MoAbs) of the IgG2a (OKT3) and IgG1 (PanT2, CLB T3/4.1) isotypes was studied in 39 patients with systemic sclerosis (SSc) and in 82 control subjects. The effect of IL-2 on this response was also investigated. No difference in the response to PHA and to IgG2a anti-CD3 MoAb OKT3 was seen between scleroderma patients and controls. Both the patient and control groups contained responders and non-responders to IgG1 anti-CD3 MoAbs. The percentage of non-responders was significantly higher in scleroderma patients than in controls. When purified lymphocytes from non-responder scleroderma patients were cultured with monocytes from control responders, proliferative response to IgG1 MoAbs was restored. Our results show that monocytes from patients with systemic sclerosis bear a defect leading to IgG1 unresponsiveness by T lymphocytes.
Valentini
G
G
Clinica Medica, I Facoltà di Medicina e Chirurgia, Napoli, Italy.
Carandente Giarrusso
P
P
Gualdieri
L
L
Corbo
L
L
Alfinito
F
F
Turco
M C
MC
Venuta
S
S
Giordano
M
M
D000293:Adolescent; D000328:Adult; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D005260:Female; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology; D012595:Scleroderma, Systemic / Q000276:immunology*
D000911:Antibodies, Monoclonal; D007132:Immunoglobulin Isotypes