Accessory cells induce a polyphosphatidylinositol response when cultured with mitogen-activated T lymphocytes.
Monocytes (MO) influenced phosphoinositide metabolism when human T lymphocytes, isolated from peripheral blood, were activated by polyclonal mitogens. In the 3 hr immediately following mitogenic challenge, the synthesis of phosphatidylinositol (PI) was augmented and the synthesis of PI-4-phosphate (PIP) and PI-4,5-bisphosphate (PIP2) was induced in cultures of T lymphocytes and MO. In addition, MO induced a rapid and transient degradation of PIP and PIP2 in T cells prelabeled with [32P]PL and subsequently activated by mitogen. Induction of a PIP/PIP2 response correlated well with induction of DNA replication by MO when T cells were activated by phytohemagglutinin or by neuraminidase plus galactose oxidase. MO did not influence polyphosphoinositide metabolism when T cells were stimulated by the nonmitogenic lectin wheat germ agglutinin. Interleukin 1 could not substitute for monocytes in inducing a polyphosphoinositide response. By causing a rapid and transient release of the second messengers diacylglycerol and inositol phosphates and by subsequently increasing their cellular precursors, MO may induce the interleukin 2 responsive state in T lymphocytes.
Akeson
A L
AL
Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Ohio 45267-0575.
Mitani
K
K
McCarthy
B M
BM
Harmony
J A
JA
D000938:Antigen-Presenting Cells / Q000502:physiology*; D005692:Galactose Oxidase / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000502:physiology*; D008934:Mitogens / Q000494:pharmacology*; D009000:Monocytes / Q000502:physiology*; D009439:Neuraminidase / Q000494:pharmacology; D010716:Phosphatidylinositols / Q000096:biosynthesis*; D010743:Phospholipids / Q000378:metabolism; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D014909:Wheat Germ Agglutinins / Q000494:pharmacology
D008934:Mitogens; D010716:Phosphatidylinositols; D010743:Phospholipids; D010835:Phytohemagglutinins; D014909:Wheat Germ Agglutinins; D005692:Galactose Oxidase; D009439:Neuraminidase