Limits...
CD47 ligation selectively downregulates human interleukin 12 production.

Armant M, Avice MN, Hermann P, Rubio M, Kiniwa M, Delespesse G, Sarfati M - J. Exp. Med. (1999)

Bottom Line: CD47 ligation did not alter transforming growth factor (TGF)-beta and IL-10 production, and the suppressive effect on IL-12 was not due to autocrine secretion of TGF-beta or IL-10.The IL-12 inhibition was not mediated by Fcgamma receptor ligation, did not require extracellular Ca(2+) influx, but was reversed by two phosphoinositide 3-kinase inhibitors (wortmannin and Ly294002).The pathway may be relevant in limiting the duration and intensity of the inflammatory response, and in developing novel therapeutic strategies for Th1-mediated diseases.

View Article: PubMed Central - PubMed

Affiliation: Laboratoire Allergie, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CHUM), Campus Notre-Dame, Quebec H2L 4M1, Canada.

ABSTRACT
Interleukin (IL)-12 plays a key role not only in protective innate and adaptive T helper cell type 1 (Th1) responses but also in chronic inflammatory diseases. We report here that engagement of CD47 by either monoclonal antibody, its natural ligand thrombospondin (TSP), or 4N1K (a peptide of the COOH-terminal domain of TSP selectively binding CD47) inhibits IL-12 release by monocytes. The suppression occurred after T cell-dependent or -independent stimulation of monocytes and was selective for IL-12 inasmuch as the production of tumor necrosis factor (TNF)-alpha, IL-1, IL-6, and granulocyte/macrophage colony-stimulating factor was not inhibited. CD47 ligation did not alter transforming growth factor (TGF)-beta and IL-10 production, and the suppressive effect on IL-12 was not due to autocrine secretion of TGF-beta or IL-10. The IL-12 inhibition was not mediated by Fcgamma receptor ligation, did not require extracellular Ca(2+) influx, but was reversed by two phosphoinositide 3-kinase inhibitors (wortmannin and Ly294002). Thus, engagement of CD47 on monocytes by TSP, which transiently accumulates at the inflammatory site, is a novel and unexplored pathway to selectively downregulate IL-12 response. The pathway may be relevant in limiting the duration and intensity of the inflammatory response, and in developing novel therapeutic strategies for Th1-mediated diseases.

Show MeSH

Related in: MedlinePlus

CD47 mAb selectively inhibits IL-12 release by purified monocytes. (A) Monocytes (106/ml) were cultured with SAC (0.01%; n = 5), SAC plus IFN-γ (500 U/ml; n = 12), or sCD40L (1 μg/ml) plus GM-CSF (25 ng/ml) plus IFN-γ (500 U/ml; n = 6) in the absence or presence of CD47 mAb (IgG1) or isotype-matched control mAb (cont; 10 μg/ml). IL-12p70 was measured in the culture supernatants after 20 h. (B) Monocytes were stimulated with SAC and IFN-γ (n = 6) in the presence of CD47 or control mAb. TNF-α, IL-1β, IL-6, and GM-CSF were measured after 20 h. Data are mean values ± SEM of n separate experiments from n different donors. ***P < 0.005; *P < 0.05. (C) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; IL-10 and TGF-β were measured after 20 h. Data are mean values ± SEM from six experiments using six different donors. (D) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; neutralizing anti–IL-10 (10 μg/ml), anti–TGF-β (30 μg), or isotype-matched control mAbs were added to the cultures. Data are mean values of duplicate cultures and represent one of three experiments using three different donors.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2195669&req=5

Figure 1: CD47 mAb selectively inhibits IL-12 release by purified monocytes. (A) Monocytes (106/ml) were cultured with SAC (0.01%; n = 5), SAC plus IFN-γ (500 U/ml; n = 12), or sCD40L (1 μg/ml) plus GM-CSF (25 ng/ml) plus IFN-γ (500 U/ml; n = 6) in the absence or presence of CD47 mAb (IgG1) or isotype-matched control mAb (cont; 10 μg/ml). IL-12p70 was measured in the culture supernatants after 20 h. (B) Monocytes were stimulated with SAC and IFN-γ (n = 6) in the presence of CD47 or control mAb. TNF-α, IL-1β, IL-6, and GM-CSF were measured after 20 h. Data are mean values ± SEM of n separate experiments from n different donors. ***P < 0.005; *P < 0.05. (C) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; IL-10 and TGF-β were measured after 20 h. Data are mean values ± SEM from six experiments using six different donors. (D) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; neutralizing anti–IL-10 (10 μg/ml), anti–TGF-β (30 μg), or isotype-matched control mAbs were added to the cultures. Data are mean values of duplicate cultures and represent one of three experiments using three different donors.

Mentions: We examined the effect of soluble CD47 mAb on IL-12 release by purified monocytes costimulated by IFN-γ and T cell–dependent (sCD40L and GM-CSF) or –independent (SAC) signals. As depicted in Fig. 1 A, CD47 mAb significantly suppressed IL-12 secretion in response to either stimuli, whereas isotype-matched IgG1 mouse mAb had no effect. In agreement with Marth and Kelsall 3, anti-CD18 mAb, used as a cell-binding irrelevant mAb, did not suppress IL-12 production (data not shown). We noted an inhibition of IL-12 release even when monocytes were cultured with SAC alone, indicating that CD47 mAb did not simply impair the enhancing effect of IFN-γ on IL-12 production. Our unpublished observations revealed a similar suppressive effect by CD47 mAb after LPS and IFN-γ costimulation.


CD47 ligation selectively downregulates human interleukin 12 production.

Armant M, Avice MN, Hermann P, Rubio M, Kiniwa M, Delespesse G, Sarfati M - J. Exp. Med. (1999)

CD47 mAb selectively inhibits IL-12 release by purified monocytes. (A) Monocytes (106/ml) were cultured with SAC (0.01%; n = 5), SAC plus IFN-γ (500 U/ml; n = 12), or sCD40L (1 μg/ml) plus GM-CSF (25 ng/ml) plus IFN-γ (500 U/ml; n = 6) in the absence or presence of CD47 mAb (IgG1) or isotype-matched control mAb (cont; 10 μg/ml). IL-12p70 was measured in the culture supernatants after 20 h. (B) Monocytes were stimulated with SAC and IFN-γ (n = 6) in the presence of CD47 or control mAb. TNF-α, IL-1β, IL-6, and GM-CSF were measured after 20 h. Data are mean values ± SEM of n separate experiments from n different donors. ***P < 0.005; *P < 0.05. (C) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; IL-10 and TGF-β were measured after 20 h. Data are mean values ± SEM from six experiments using six different donors. (D) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; neutralizing anti–IL-10 (10 μg/ml), anti–TGF-β (30 μg), or isotype-matched control mAbs were added to the cultures. Data are mean values of duplicate cultures and represent one of three experiments using three different donors.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2195669&req=5

Figure 1: CD47 mAb selectively inhibits IL-12 release by purified monocytes. (A) Monocytes (106/ml) were cultured with SAC (0.01%; n = 5), SAC plus IFN-γ (500 U/ml; n = 12), or sCD40L (1 μg/ml) plus GM-CSF (25 ng/ml) plus IFN-γ (500 U/ml; n = 6) in the absence or presence of CD47 mAb (IgG1) or isotype-matched control mAb (cont; 10 μg/ml). IL-12p70 was measured in the culture supernatants after 20 h. (B) Monocytes were stimulated with SAC and IFN-γ (n = 6) in the presence of CD47 or control mAb. TNF-α, IL-1β, IL-6, and GM-CSF were measured after 20 h. Data are mean values ± SEM of n separate experiments from n different donors. ***P < 0.005; *P < 0.05. (C) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; IL-10 and TGF-β were measured after 20 h. Data are mean values ± SEM from six experiments using six different donors. (D) Monocytes were stimulated with SAC and IFN-γ in the presence of CD47 or control mAb; neutralizing anti–IL-10 (10 μg/ml), anti–TGF-β (30 μg), or isotype-matched control mAbs were added to the cultures. Data are mean values of duplicate cultures and represent one of three experiments using three different donors.
Mentions: We examined the effect of soluble CD47 mAb on IL-12 release by purified monocytes costimulated by IFN-γ and T cell–dependent (sCD40L and GM-CSF) or –independent (SAC) signals. As depicted in Fig. 1 A, CD47 mAb significantly suppressed IL-12 secretion in response to either stimuli, whereas isotype-matched IgG1 mouse mAb had no effect. In agreement with Marth and Kelsall 3, anti-CD18 mAb, used as a cell-binding irrelevant mAb, did not suppress IL-12 production (data not shown). We noted an inhibition of IL-12 release even when monocytes were cultured with SAC alone, indicating that CD47 mAb did not simply impair the enhancing effect of IFN-γ on IL-12 production. Our unpublished observations revealed a similar suppressive effect by CD47 mAb after LPS and IFN-γ costimulation.

Bottom Line: CD47 ligation did not alter transforming growth factor (TGF)-beta and IL-10 production, and the suppressive effect on IL-12 was not due to autocrine secretion of TGF-beta or IL-10.The IL-12 inhibition was not mediated by Fcgamma receptor ligation, did not require extracellular Ca(2+) influx, but was reversed by two phosphoinositide 3-kinase inhibitors (wortmannin and Ly294002).The pathway may be relevant in limiting the duration and intensity of the inflammatory response, and in developing novel therapeutic strategies for Th1-mediated diseases.

View Article: PubMed Central - PubMed

Affiliation: Laboratoire Allergie, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CHUM), Campus Notre-Dame, Quebec H2L 4M1, Canada.

ABSTRACT
Interleukin (IL)-12 plays a key role not only in protective innate and adaptive T helper cell type 1 (Th1) responses but also in chronic inflammatory diseases. We report here that engagement of CD47 by either monoclonal antibody, its natural ligand thrombospondin (TSP), or 4N1K (a peptide of the COOH-terminal domain of TSP selectively binding CD47) inhibits IL-12 release by monocytes. The suppression occurred after T cell-dependent or -independent stimulation of monocytes and was selective for IL-12 inasmuch as the production of tumor necrosis factor (TNF)-alpha, IL-1, IL-6, and granulocyte/macrophage colony-stimulating factor was not inhibited. CD47 ligation did not alter transforming growth factor (TGF)-beta and IL-10 production, and the suppressive effect on IL-12 was not due to autocrine secretion of TGF-beta or IL-10. The IL-12 inhibition was not mediated by Fcgamma receptor ligation, did not require extracellular Ca(2+) influx, but was reversed by two phosphoinositide 3-kinase inhibitors (wortmannin and Ly294002). Thus, engagement of CD47 on monocytes by TSP, which transiently accumulates at the inflammatory site, is a novel and unexplored pathway to selectively downregulate IL-12 response. The pathway may be relevant in limiting the duration and intensity of the inflammatory response, and in developing novel therapeutic strategies for Th1-mediated diseases.

Show MeSH
Related in: MedlinePlus