Search results for "Lymphokine"

Lymphokine profile and activation pattern of two unrelated antigen- or idiotype-specific T suppressor cell clones.

1992

Two T suppressor (Ts) clones of different specificity have been analyzed for their lymphokine spectrum. BVI/5 is an I-Ek-restricted bovine serum albumin (BSA)-specific Ts cell clone from a CBA/J mouse tolerized by low doses of BSA. It affects directly or indirectly the function of BSA-specific T helper (Th) cells. The Ts cell clone 178-4 from a BALB/c mouse is I-Ed restricted and recognizes the public J558 Id on B cells. It prevents alpha(1----3)dextran B 1355S (Dex)-specific IgG antibody production and drives Dex-specific J558 idiotype-bearing B cells into an anergic B IgG memory cell state. Both Ts cell clones thus cause specific suppression, yet in different experimental systems using di…

Interleukin-7

2003

This chapter discusses interleukin (IL)-7, which is an important lymphopoietin that plays a critical role in both B- and T-cell development. IL-7 promotes expansion of T lymphocytes exhibiting antigen-specific reactivity. IL-7 may be implemented to promote strong and effective immune responses against tumor cells, or directed against microbial or viral infections. It may also be useful in reconstituting an effective, and functional immune system after bone marrow transplantation, or helping to design novel strategies for immune reconstitution in patients with cancer or with HIV infection. IL-7 serves as the major growth and differentiation factor for both thymic and extrathymic development …

Human interleukin 2: molecular biology, physiology and clinical possibilities.

1986

T cell factor (interleukin 2) allows in vivo induction of T helper cells against heterologous erythrocytes in athymic (nu/nu) mice.

1980

Mice carrying the nude mutation (nu/nu) lack a functioning thymus and do not contain detectable levels of immunocompetent T cells. We now report that nu/nu mice do have lymphocytes which can be activated in vivo by heterologous erythrocytes and a Lyt-1 T cell-derived factor (interleukin 2) to generate T helper cells. Thus, a lymphokine is described which is able to restore in vivo T helper cell immunocompetence of nu/nu mice. The data may suggest that nu/nu mice contain a low number of T lymphocytes influenced by the cystic remnant of the nu/nu thymus anlage. Alternatively, the data imply that interleukin 2 circumvents the requirement of a thymus during ontogeny of T lymphocytes.

Establishment of different T cell sublines using either interleukin 2 or interleukin 4 as growth factors

1990

Purified protein derivative reactive T cell lines were established under identical conditions with the exception that different lymphokines, namely interleukin (IL) 2 and IL 4 were employed as growth factors. IL 2 favored the development of T cell lines (LNC.2) which upon activation by concanavalin A (Con A) secreted predominantly lymphokines characteristic of TH1 cells. By contrast, T cell lines established with the aid of IL 4 as growth factor (LNC.4) produced mainly lymphokines representative of TH2 cells. Apart from their pattern of lymphokine secretion LNC.2 and LNC.4 T cells were found to differ in their proliferative response to lymphokines and Con A. LNC.2 T cells proliferated only …

B8, DR3 antigens and production of human leucocyte migration inhibitory factor (LIF) by mononuclear cells stimulated with concanavalin A (Con A)

2008

LIF release by Con A stimulated mononuclear cells was evaluated in 67 randomly selected healthy Sicilians typed for HLA antigens. The results show that B8 and/or DR3 positive subjects release less LIF than negative ones, suggesting that this immunological response might be controlled by HLA-linked immune response (Ir) gene(s).

Spontaneous lymphokine production by human B lymphocytes.

2009

When human blood lymphocytes are cultured in vitro without any intended stimulus, they produce activities in the supernatant resembling lymphokine. This phenomenon was further investigated in the present study, where it has been demonstrated by physicochemical characterization and inhibition experiments that leukocyte migration inhibitory activity in the supernatants is due to leukocyte inhibitory factor (LIF). When T and B lymphocytes were purified by carbonyl iron and SRBC-rosette sedimentation, only B cells produced LIF and leukocyte chemotactic lymphokine(s) in subsequent cultures. B cells elaborated lymphokines without the help of T cells, the need for co-operation of monocytes was als…

Modulation of Forssman Glycosphingolipid Expression by Murine Macrophages: Coinduction with Class II MHC Antigen by the Lymphokines IL4 and IL6

1990

In contrast to murine spleen M phi, resident peritoneal M phi from health mice express very little Forssman glycolipid antigen (Fo). The following experiments suggest that Fo expression by peritoneal M phi may be associated with inflammation. Balb/c and CBA/J mice were given inflammatory stimuli by i.p. injection of live BCG, thioglycollate (TG), Corynebacterium parvum (CP), proteose peptone (PP), or LPS. Control animals received pyrogen-free saline. Expression of Fo and Ia antigen by peritoneal M phi was determined by immunofluorescence after 4 d. Application of TG or CP led to an up to 30-fold increase in Fo+, Ia+ double positive M phi over that in control animals. LPS caused mainly an in…

Interleukin 2 and interleukin 15 differentially predispose natural killer cells to apoptosis mediated by endothelial and tumour cells

2001

Human natural killer (NK) cells constitutively express the beta- and gamma-chains of the interleukin 2 (IL-2)/IL-15 receptor, and both IL-2 and IL-15 are able to activate NK cell proliferation and cytotoxicity. When IL-2-primed human NK cells are exposed to sensitive targets (i.e. K562) they undergo apoptosis mediated by the beta(2)-integrin CD18. Here, we demonstrate that: (i) endothelial cells, similar to K562 tumour target cells, induce apoptosis of IL-2-primed NK cells; (ii) endothelial- and K562 cell-induced apoptosis is significantly lower in IL-15 than in IL-2-stimulated NK cells; (iii) a critical role in the apoptosis of IL-2-primed NK cells is played by the alpha-chain of the IL-2 …

CD4+CD25+ regulatory T cells inhibit natural killer cell functions in a transforming growth factor-beta-dependent manner.

2007

Tumor growth promotes the expansion of CD4+CD25+ regulatory T (T reg) cells that counteract T cell–mediated immune responses. An inverse correlation between natural killer (NK) cell activation and T reg cell expansion in tumor-bearing patients, shown here, prompted us to address the role of T reg cells in controlling innate antitumor immunity. Our experiments indicate that human T reg cells expressed membrane-bound transforming growth factor (TGF)–β, which directly inhibited NK cell effector functions and down-regulated NKG2D receptors on the NK cell surface. Adoptive transfer of wild-type T reg cells but not TGF-β−/− T reg cells into nude mice suppressed NK cell–mediated cytotoxicity, redu…