Figure 1.
Injection of anti-CD25 mAb sufficiently depletes CD4+CD25+ regulatory T cells in vivo continuously.
(A) C57BL/6 mice were treated i.p. with 100 µg anti-CD25 mAb or control IgG, the percentage of CD4+CD25+ Treg cells in the spleen was assayed by using anti-CD4 and CD25 mAb by flow cytometry. (n = 5) (B) Percentage of CD4+ T cells expressing CD25 was shown in the graph. (n = 5) (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05).
Figure 2.
Depletion of Treg cells increases the accumulation of inflammation cells in lung response to silica.
The total cells (A), neutrophils (B), macrophages (C) and lymphocytes (D) in BALF were counted by using Giemsa staining. (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05; #, as compare with 7day of the same group, P<0.05; &, as compare with 28day of the same group, P<0.05).
Figure 3.
Histopathology changes in mouse lungs after instillation with HE staining (x200).
a1-a3, day 7; b1-b3, day 28 and c1-c3, day 56. a1-c1, saline group; a2-c2, silica group; a3-c3,silica+anti-CD25mAb.
Table 1.
Silicotic nodule of the mice lungs in each group at day 7, 28 and 56.
Figure 4.
CD4+CD25+FOXP3+ T cells were the functional fraction of Treg cells in the silica-induced lung fibrosis.
Treg cells in HLN (A), spleen (C) and BALF (E) were calculated by flow cytometry. (n = 5) The percentage of CD4+ T cells expressing CD25 and FOXP3 was shown in the graph (B, HLN; D, spleen; F, BALF) (n = 5) (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05; #, as compare with 7day of the same group, P<0.05; &, as compare with 28day of the same group, P<0.05).
Figure 5.
Treg cells affect the Th1/Th2 balance in the mice model of silica-induced lung fibrosis.
Typical Th1 (IL-2) (A) and Th2 (IL-4)(B) cytokines were assayed by realtime RT-PCR by using -△△Ct method. (n = 5) (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05; #, as compare with 7day of the same group, P<0.05).
Figure 6.
The expression of CTLA-4 in Treg cells in the HLN and spleen.
CTLA4 expressed in CD4+CD25+FOXP3+ Treg cells of HLN (A) and spleen (C) was assayed by flow cytometry. (n = 5) The number of Treg cells expressing CTLA4 of HLN (B) and spleen (D) was shown in the graph. (n = 5) (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05; #, as compare with 7day of the same group, P<0.05; &, as compare with 28day of the same group, P<0.05).
Figure 7.
The function of Treg cells depends on both IL-10 (A) and TGF-β (B).
The IL-10 and TGF-β mRNA were assayed by realtime RT-PCR by using -△△Ct method. (n = 5) (*, as compare with the saline control group, P<0.05; △, as compare with the silica group, P<0.05; #, as compare with 7day of the same group, P<0.05; &, as compare with 28day of the same group, P<0.05).