CD40 expression by human monocytes: regulation by cytokines and activation of monocytes by the ligand for CD40.

Abstract

SummaryCD40 is a member of the tumor necrosis factor (TNF) receptor family of cell surface proteins and was originally described as a B cell restricted antigen. Treatment of primary human monocytes with granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), or interferon 3' (IFN-3') resulted in the induction of CD40 mRNA and enhancement of cell surface protein expression. CD40 was found to mediate monocyte adhesion to cells expressing recombinant CD40 ligand. CD40 ligand-transfected cells provided a potent costimulus for monocyte TNF-ot and IL-6 production in the presence of GM-CSF, IL-3, or IFN-3', and enhanced IL-8 production stimulated by GM-CSF or IL-3. In addition, CD40 ligand-transfected cells acting in the absence of a costimulus induced monocytes to become tumoricidal against a human mdanoma cell target. Collectively, these data indicate that CD40 ligand is pleiotropic with potent biological activity on monocytes.C D40 is a 50-kD molecule expressed on B cells, dendritic cells, some carcinoma cell lines, and human thymic epithelium (1-3). Abs specific for CD40 exhibit stimulatory effects on IL-4 activated B cells, including the induction of B cell growth, IgE secretion, and expression of CD23 (4-7). Human and murine forms of a ligand for CD40 (CD40L) 1 were recently cloned and demonstrated to be type II integral membrane proteins expressed primarily on activated CD4 + T cells (8)(9)(10)(11). CD40L provides a strong stimulatory signal to B cells from both species (8-10), however little is known about the regulation of expression of CD40 and the effects of CD40L on other cell types.Monocytes express a variety of cell surface proteins that are thought to play an important role in antigen presentation and the cell contact-dependent interaction of monocytes with other leukocytes. The expression of many of these proteins on monocytes can be regulated by a variety of cytokines, including GM-CSF, IL-3, IL-4, IFN-3", and . In this paper, we demonstrate that GM-CSF, IL-3, and IFN-'r enhance expression of CD40 by normal human monocytes. In addition, culture of monocytes with CD40L resulted in the stimulation or costimulation of cytokine production and in the induction of monocyte tumoricidal activity. Thus, CD40L is involved in the regulation of several critical aspects 1 Abbreviation used in this paper: L, ligand. of the immune response, and may be important in the cell contact-dependent activation of both T cells and monocytes during antigen presentation. Materials and MethodsMonocyte Purification and Culture. Monocytes were purified from normal donor PBMC by countercurrent elutriation (17) and were ~95 % pure by microscopic examination of Giemsa-stained cytocentrifuge preparations. Cells were cultured in RPMI 1640 medium containing 10% low endotoxin FBS, 50 U/ml penicillin, 50/zg/ml streptomycin, and 5 x 10 -s M 2-ME. Monocytes were cultured in polypropylene tubes (Falcon; Becton Dickinson Labware, Lincoln Park, NJ) for flow cytometry and mRNA analysis, in 24-well plates (Costar Corp., C...

Induction of antitumor immunity by transduction of CD40 ligand gene and interferon-γ gene into lung cancer

“…26 In addition, CD40 ligation on macrophages or monocytes enhances their TNF -production, and induces tumoricidal activity. 27 We have previously demonstrated that the 3LLSA -CD40L used in this study could activate murine alveolar macrophages and enhance their tumoricidal activity in vitro. 11 It is also known that CD40 ligation inhibits spontaneous or tumor-induced apoptosis of dendritic cells.…”

“…One is that macrophages or dendritic cells at the tumor site are activated through CD40 ± CD40L interaction, and they release cytokines and mediators such as TNF -or nitric oxide to kill tumor cells. 27 They also release IL-12 to recruit NK cells those are important for eliciting local antitumor response. 32 Our imunohistochemical study showing the enhanced infiltration of NK cells into 3LLSA -CD40L tumor may support this scenario.…”

Expression of accessory molecules and cytokines in acute EAE in marmoset monkeys (Callithrix jacchus)

“…CD40 can also be functionally expressed on Ž . macrophages Alderson et al, 1993 , and mediates T Ž cell-macrophage interactions Wiley and Harmsen, 1995;Campbell et al, 1996;Kamanaka et al, 1996;Soong et al, . 1996;Stout et al, 1996 .…”

“…tion function of macrophages Kiener et al, 1995 . Functionally, CD40L supplied a costimulus for production of the pro-inflammatory cytokines TNF-a, IL-1b, IL-6, IL-8 Ž and IL-12 Alderson et al, 1993;Wagner et al, 1994;Shu et al, 1995;Kennedy et al, 1996 . Ž .…”

Types I and II interferons upregulate the costimulatory CD80 molecule in monocytes via interferon regulatory factor-1

“…Previous studies have shown that TNF-, IFN- and IFN- upregulate CD40 expression in various cell types including monocytes [24,25]. NF-B and IRF-1 have been implicated in the regulation of CD40 expression [26][27][28].…”