Functional interaction between interleukin-9/P40 and interleukin-4 in the induction of IgE production by normal human B lymphocytes.
Interleukin-4 (IL-4) has been shown to induce a high rate of IgE production by normal B lymphocytes from peripheral blood without preactivation of these cells. In the present study, significant IgE production was observed at the concentration of 30 U/mL IL-4 (0.5 ng IgE/mL), and a plateau value was reached at 300 U/mL (1.2 ng IgE/mL). In these experiments, recombinant human (rh) and murine (rm) interleukin-9/P40 (IL-9/P40) were unable to induce such an IgE production by human B lymphocytes. However, in the presence of a suboptimal dose of IL-4 (100 U/mL), both rh and rm IL-9/P40 enhanced the IgE production in a dose-dependent manner (from 3 to 1000 U/mL). Under these experimental conditions, the slight but significant (p < 0.01, Student's t test) production of IgG (50 ng/mL) was also potentiated when the cell cultures were performed in the presence of 300 U/mL of IL-9/P40. The IL-4-induced IgG and IgM production by purified B lymphocytes preactivated with Staphylococcus aureus Cowan strain I was also potentiated in the presence of 300 U/mL of rh IL-9/P40, indicating a direct effect of this cytokine on this cell type. In contrast, IgE production by Staphylococcus aureus Cowan strain I-activated B lymphocytes was never observed. Taken together these data suggested a direct role for IL-9/P40 in the regulation of immunoglobulin production by B lymphocytes.
Institut Henri Beaufour, Les Ulis, France.
B
B
Dugas
J
J
Van Snick
J C
JC
Renauld
P
P
Braquet
J M
JM
Mencia-Huerta
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007073:Immunoglobulin E / Q000096:biosynthesis*; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D015847:Interleukin-4 / Q000494:pharmacology*; D016906:Interleukin-9 / Q000494:pharmacology*; D008213:Lymphocyte Activation; D051379:Mice; D011994:Recombinant Proteins / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000276:immunology
D007074:Immunoglobulin G; D007075:Immunoglobulin M; D016906:Interleukin-9; D011994:Recombinant Proteins; D015847:Interleukin-4; D007073:Immunoglobulin E