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Enhanced antitumor immunity in mice deficient in CD69.

Esplugues E, Sancho D, Vega-Ramos J, Martínez C, Syrbe U, Hamann A, Engel P, Sánchez-Madrid F, Lauzurica P - J. Exp. Med. (2003)

Bottom Line: The enhanced anti-tumor response was NK cell and T lymphocyte-mediated, and was due, at least in part, to an increase in local lymphocytes.Resistance of CD69-/- mice to MHC class I- tumor growth was also associated with increased production of the chemokine MCP-1, diminished TGF-beta production, and decreased lymphocyte apoptosis.In addition, CD69 engagement induced NK and T cell production of TGF-beta, directly linking CD69 signaling to TGF-beta regulation.

View Article: PubMed Central - PubMed

Affiliation: Departmento de Fisiología, Universidad de Barcelona, Barcelona 08080 Spain.

ABSTRACT
We investigated the in vivo role of CD69 by analyzing the susceptibility of CD69-/- mice to tumors. CD69-/- mice challenged with MHC class I- tumors (RMA-S and RM-1) showed greatly reduced tumor growth and prolonged survival compared with wild-type (WT) mice. The enhanced anti-tumor response was NK cell and T lymphocyte-mediated, and was due, at least in part, to an increase in local lymphocytes. Resistance of CD69-/- mice to MHC class I- tumor growth was also associated with increased production of the chemokine MCP-1, diminished TGF-beta production, and decreased lymphocyte apoptosis. Moreover, the in vivo blockade of TGF-beta in WT mice resulted in enhanced anti-tumor response. In addition, CD69 engagement induced NK and T cell production of TGF-beta, directly linking CD69 signaling to TGF-beta regulation. Furthermore, anti-CD69 antibody treatment in WT mice induced a specific down-regulation in CD69 expression that resulted in augmented anti-tumor response. These data unmask a novel role for CD69 as a negative regulator of anti-tumor responses and show the possibility of a novel approach for the therapy of tumors.

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Attenuation of spontaneous cell death of CD69−/− lymphocytes. (A) Unfractionated peritoneal cells of untreated mice were seeded in culture medium and cell survival was measured by PI staining. Values show the percentage of PI+ cells (mean ± SD; n = 3 for each group). Results are representative of three independent experiments. (B) Analysis of intracellular caspase-3 activity of spleen cells from WT (left) and CD69−/− (right) challenge mice (3 d with 105 RM-1). Caspase-3 activation was detected with fluorogenic substrate PhiPhiLux-G1D2. PhiPhiLux staining on FL-1 versus forward scatter channels was displayed. (C) After gating on DX5+ cells from spleen, caspase-3 activity was assayed. At least 100,000 events were collected per sample. Experiments were done twice with four and six mice per group; and similar results were obtained.
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fig6: Attenuation of spontaneous cell death of CD69−/− lymphocytes. (A) Unfractionated peritoneal cells of untreated mice were seeded in culture medium and cell survival was measured by PI staining. Values show the percentage of PI+ cells (mean ± SD; n = 3 for each group). Results are representative of three independent experiments. (B) Analysis of intracellular caspase-3 activity of spleen cells from WT (left) and CD69−/− (right) challenge mice (3 d with 105 RM-1). Caspase-3 activation was detected with fluorogenic substrate PhiPhiLux-G1D2. PhiPhiLux staining on FL-1 versus forward scatter channels was displayed. (C) After gating on DX5+ cells from spleen, caspase-3 activity was assayed. At least 100,000 events were collected per sample. Experiments were done twice with four and six mice per group; and similar results were obtained.

Mentions: In the periphery, homeostatic mechanisms regulate the expansion and elimination of activated cells (25). To investigate the mechanism of lymphocyte accumulation in CD69−/− mouse spleen and peritoneum, we analyzed immune cell survival in these mice. When peritoneal cell viability was studied in vitro, an increase in cell survival was detected in CD69−/− compared with WT mice (Fig. 6 A). A significant decrease in spontaneous apoptosis (24 h) of spleen lymphocytes from RM-1–challenged CD69−/− (23.36 ± 1.73%, n = 9) compared with WT mice (28.89 ± 1.18%, n = 9) was detected as reduced DNA content by cell cycle analyses (unpublished data; P ≤ 0.02). In addition, a significant decrease in spontaneous apoptosis (48 h) of spleen lymphocytes from RM-1–challenged CD69−/− (25.46 ± 0.5%, n = 6) compared with WT mice (44.56 ± 1.3%, n = 6) was also measured by caspase-3 activation analysis (Fig. 6 B; P ≤ 0.0001). Likewise, a significant decrease in spontaneous apoptosis (48 h) was observed when caspase-3 activation analyses were performed in DX5+ CD3− NK splenocytes from RM-1–challenged CD69−/− (36.98 ± 1.5%, n = 4) compared with WT mice (49.78 ± 3.9%, n = 4; Fig. 6 C, P ≤ 0.02). Thus, it appears that differences in lymphocyte survival may contribute to the elevated spleen size and cellularity observed in peritoneum of CD69−/− mice.


Enhanced antitumor immunity in mice deficient in CD69.

Esplugues E, Sancho D, Vega-Ramos J, Martínez C, Syrbe U, Hamann A, Engel P, Sánchez-Madrid F, Lauzurica P - J. Exp. Med. (2003)

Attenuation of spontaneous cell death of CD69−/− lymphocytes. (A) Unfractionated peritoneal cells of untreated mice were seeded in culture medium and cell survival was measured by PI staining. Values show the percentage of PI+ cells (mean ± SD; n = 3 for each group). Results are representative of three independent experiments. (B) Analysis of intracellular caspase-3 activity of spleen cells from WT (left) and CD69−/− (right) challenge mice (3 d with 105 RM-1). Caspase-3 activation was detected with fluorogenic substrate PhiPhiLux-G1D2. PhiPhiLux staining on FL-1 versus forward scatter channels was displayed. (C) After gating on DX5+ cells from spleen, caspase-3 activity was assayed. At least 100,000 events were collected per sample. Experiments were done twice with four and six mice per group; and similar results were obtained.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2193974&req=5

fig6: Attenuation of spontaneous cell death of CD69−/− lymphocytes. (A) Unfractionated peritoneal cells of untreated mice were seeded in culture medium and cell survival was measured by PI staining. Values show the percentage of PI+ cells (mean ± SD; n = 3 for each group). Results are representative of three independent experiments. (B) Analysis of intracellular caspase-3 activity of spleen cells from WT (left) and CD69−/− (right) challenge mice (3 d with 105 RM-1). Caspase-3 activation was detected with fluorogenic substrate PhiPhiLux-G1D2. PhiPhiLux staining on FL-1 versus forward scatter channels was displayed. (C) After gating on DX5+ cells from spleen, caspase-3 activity was assayed. At least 100,000 events were collected per sample. Experiments were done twice with four and six mice per group; and similar results were obtained.
Mentions: In the periphery, homeostatic mechanisms regulate the expansion and elimination of activated cells (25). To investigate the mechanism of lymphocyte accumulation in CD69−/− mouse spleen and peritoneum, we analyzed immune cell survival in these mice. When peritoneal cell viability was studied in vitro, an increase in cell survival was detected in CD69−/− compared with WT mice (Fig. 6 A). A significant decrease in spontaneous apoptosis (24 h) of spleen lymphocytes from RM-1–challenged CD69−/− (23.36 ± 1.73%, n = 9) compared with WT mice (28.89 ± 1.18%, n = 9) was detected as reduced DNA content by cell cycle analyses (unpublished data; P ≤ 0.02). In addition, a significant decrease in spontaneous apoptosis (48 h) of spleen lymphocytes from RM-1–challenged CD69−/− (25.46 ± 0.5%, n = 6) compared with WT mice (44.56 ± 1.3%, n = 6) was also measured by caspase-3 activation analysis (Fig. 6 B; P ≤ 0.0001). Likewise, a significant decrease in spontaneous apoptosis (48 h) was observed when caspase-3 activation analyses were performed in DX5+ CD3− NK splenocytes from RM-1–challenged CD69−/− (36.98 ± 1.5%, n = 4) compared with WT mice (49.78 ± 3.9%, n = 4; Fig. 6 C, P ≤ 0.02). Thus, it appears that differences in lymphocyte survival may contribute to the elevated spleen size and cellularity observed in peritoneum of CD69−/− mice.

Bottom Line: The enhanced anti-tumor response was NK cell and T lymphocyte-mediated, and was due, at least in part, to an increase in local lymphocytes.Resistance of CD69-/- mice to MHC class I- tumor growth was also associated with increased production of the chemokine MCP-1, diminished TGF-beta production, and decreased lymphocyte apoptosis.In addition, CD69 engagement induced NK and T cell production of TGF-beta, directly linking CD69 signaling to TGF-beta regulation.

View Article: PubMed Central - PubMed

Affiliation: Departmento de Fisiología, Universidad de Barcelona, Barcelona 08080 Spain.

ABSTRACT
We investigated the in vivo role of CD69 by analyzing the susceptibility of CD69-/- mice to tumors. CD69-/- mice challenged with MHC class I- tumors (RMA-S and RM-1) showed greatly reduced tumor growth and prolonged survival compared with wild-type (WT) mice. The enhanced anti-tumor response was NK cell and T lymphocyte-mediated, and was due, at least in part, to an increase in local lymphocytes. Resistance of CD69-/- mice to MHC class I- tumor growth was also associated with increased production of the chemokine MCP-1, diminished TGF-beta production, and decreased lymphocyte apoptosis. Moreover, the in vivo blockade of TGF-beta in WT mice resulted in enhanced anti-tumor response. In addition, CD69 engagement induced NK and T cell production of TGF-beta, directly linking CD69 signaling to TGF-beta regulation. Furthermore, anti-CD69 antibody treatment in WT mice induced a specific down-regulation in CD69 expression that resulted in augmented anti-tumor response. These data unmask a novel role for CD69 as a negative regulator of anti-tumor responses and show the possibility of a novel approach for the therapy of tumors.

Show MeSH
Related in: MedlinePlus