T lymphocytes from patients with systemic lupus erythematosus show increased response to interleukin-2 after costimulation with OKT3 monoclonal antibody and phorbol esters.
In the present study we have examined the potential contribution of IL-2/IL-2R interactions in CD3-mediated responses by T lymphocytes from patients with systemic lupus erythematosus (SLE). T-cells from SLE patients showed normal IL-2 production when activated with OKT3 MAb and submitogenic concentrations of PMA, in cultures in which uptake of endogenous IL-2 was prevented by pretreatment with anti-Tac MAb. In contrast, PHA-induced IL-2 production was lower in patients under the same conditions. Under these stimulatory conditions the proportions of T-cells expressing IL-2R CD25 molecules was comparable in patients and controls. There was earlier and higher binding of exogenously added IL-2 in T lymphocytes from patients activated via the CD3 pathway. Furthermore, these cells responded to IL-2 with stronger proliferative responses than cells from control subjects. These findings may partly explain the increased proliferative responses of SLE T-cells when stimulated via the CD3 pathway.
Blasini
A M
AM
Centro Nacional de Enfermedades Reumaticas, Hospital Universitario de Caracas, Venezuela.
Stekman
I L
IL
Gonzalez
F
F
Tositti
M L
ML
Rodriguez
M A
MA
D000328:Adult; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism / Q000494:pharmacology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008213:Lymphocyte Activation; D008875:Middle Aged; D016853:Muromonab-CD3 / Q000276:immunology*; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D007376:Interleukin-2; D016853:Muromonab-CD3; D015375:Receptors, Interleukin-2; D013755:Tetradecanoylphorbol Acetate