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1.
Migration of blood-borne lymphocytes into lymphoid tissues and sites of inflammation is initiated by vascular adhesion molecules and proinflammatory cytokines. Previous in vivo studies have shown that febrile temperatures dynamically stimulate adhesion in differentiated high endothelial venules (HEV), which are portals for lymphocyte extravasation. This report examines the direct effect of fever-range hyperthermia on the expression of adhesion molecules and cytokines by primary cultured endothelial cells. In both macrovascular (HUVEC) and microvascular (HMVEC) endothelial cells, fever-range hyperthermia (40°C for 6-12h) did not affect expression of adhesion molecules (ICAM-1, E-selectin, VCAM-1, P-selectin, PECAM-1, PNAd, MAdCAM-1), cytokine release (IL-1 &#103 , TNF- &#102 , IFN- &#110 , IL-6, IL-11, IL-12, IL-13), or chemokine secretion (IL-8, RANTES, MCP-1, MIP-1 &#103 , MIG). This is in contrast to the stimulatory effects of TNF- &#102 or 43°C heat shock. However, a novel role for fever-range hyperthermia was identified in augmenting actin polymerization in cultured endothelial cells and enhancing the ability of endothelial-derived factors to transactivate the &#102 4 &#103 7 integrin lymphocyte homing receptor. These findings provide insight into the tightly regulated effects of fever-range hyperthermia that exclude induction of adhesion in non-activated endothelium of normal blood vessels. Through these mechanisms, it is proposed that febrile temperatures associated with infection or clinical hyperthermia avoid the unproductive exodus of lymphocytes to non-involved extralymphoid tissues while simultaneously promoting lymphocyte delivery to sites of immune activation.  相似文献   

2.
Migration of blood-borne lymphocytes into lymphoid tissues is initiated by the L-selectin and alpha4beta7 integrin adhesion molecules. Previous studies have shown that L-selectin adhesion is dynamically regulated by febrile temperatures. It is now reported that fever-range hyperthermia also acts directly on lymphocytes to enhance selected adhesive functions of alpha4beta7 integrin. Fever-range hyperthermia treatment in vitro (40 degrees C, 12 h) of murine TK1 lymphoma cells and human peripheral blood lymphocytes (PBL) stimulates alpha4beta7 integrin-dependent adhesion to high endothelial venules (HEV) in Peyer's patch and mesenteric lymph node frozen sections. TK1 cells are alpha4beta7hi L-selectin(lo), allowing for the analysis of alpha4beta7 integrin without contributions from L-selectin. Adhesion was further shown to involve alpha4beta7 integrin and its endothelial counter-receptor, mucosal addressin cell adhesion molecule-1 (MAdCAM-1) using function-blocking antibodies (i.e. DATK32, HP2/1, MECA-367). Fever-range hyperthermia also promotes alpha4beta7 integrin-mediated aggregation of TK1 cells. In sharp contrast, hyperthermia fails to increase alpha4beta7 integrin adhesion to fibronectin by TK1 cells. Expression of the alpha4beta7 heterodimer on TK1 cells or human PBL is not altered by hyperthermia, suggesting that hyperthermia stimulates adhesion by enhancing alpha4beta7 integrin avidity rather than its cell surface density. These results provide a mechanism whereby febrile temperatures during infection or clinical hyperthermia potentially amplify the immune response by stimulating L-selectin and alpha4beta7 integrin-dependent homing of immune effector cells to lymphoid tissues.  相似文献   

3.
Migration of blood-borne lymphocytes into lymphoid tissues is initiated by the Lselectin and alpha4beta7 integrin adhesion molecules. Previous studies have shown that L-selectin adhesion is dynamically regulated by febrile temperatures. It is now reported that fever-range hyperthermia also acts directly on lymphocytes to enhance selected adhesive functions of alpha4beta7 integrin. Fever-range hyperthermia treatment in vitro (40oC, 12h) of murine TK1 lymphoma cells and human peripheral blood lymphocytes (PBL) stimulates alpha4beta7 integrin-dependent adhesion to high endothelial venules (HEV) in Peyer's patch and mesenteric lymph node frozen sections. TK1 cells are alpha4beta7hi L-selectinlo, allowing for the analysis of alpha4beta7 integrin without contributions from L-selectin. Adhesion was further shown to involve alpha4beta7 integrin and its endothelial counter-receptor, mucosal addressin cell adhesion molecule-1 (MAdCAM-1) using function-blocking antibodies (i.e. DATK32, HP2/1, MECA-367). Fever-range hyperthermia also promotes alpha4beta7 integrin-mediated aggregation of TK1 cells. In sharp contrast, hyperthermia fails to increase alpha4beta7 integrin adhesion to fibronectin by TK1 cells. Expression of the alpha4beta7 heterodimer on TK1 cells or human PBL is not altered by hyperthermia, suggesting that hyperthermia stimulates adhesion by enhancing alpha4beta7 integrin avidity rather than its cell surface density. These results provide a mechanism whereby febrile temperatures during infection or clinical hyperthermia potentially amplify the immune response by stimulating L-selectin and alpha4beta7 integrin-dependent homing of immune effector cells to lymphoid tissues.  相似文献   

4.
Immune protection from microbial invaders or malignant progression is dependent on the ability of lymphocytes to efficiently traffic across morphologically and biochemically distinct vascular sites throughout the body. Lymphocyte trafficking to target tissues is orchestrated by adhesion molecules and chemokines that stabilize dynamic interactions between circulating lymphocytes and endothelial cells lining blood vessels. While the molecular mechanisms that regulate the efficient migration of lymphocytes across specialized high endothelial venules (HEVs) in secondary lymphoid organs have been extensively characterized, there is a paucity of information available regarding the mechanisms that dictate the rate of lymphocyte entry into tumor tissues. This article summarizes recent evidence that inflammatory cues associated with fever-range thermal stress promote lymphocyte extravasation across HEVs of lymphoid organs through a highly regulated lymphocyte–endothelial–interleukin-6 (IL-6) biological axis. The potential for using thermally-based strategies to improve lymphocyte delivery to the tumor microenvironment during T cell-based immunotherapy will also be discussed.  相似文献   

5.
Immune protection from microbial invaders or malignant progression is dependent on the ability of lymphocytes to efficiently traffic across morphologically and biochemically distinct vascular sites throughout the body. Lymphocyte trafficking to target tissues is orchestrated by adhesion molecules and chemokines that stabilize dynamic interactions between circulating lymphocytes and endothelial cells lining blood vessels. While the molecular mechanisms that regulate the efficient migration of lymphocytes across specialized high endothelial venules (HEVs) in secondary lymphoid organs have been extensively characterized, there is a paucity of information available regarding the mechanisms that dictate the rate of lymphocyte entry into tumor tissues. This article summarizes recent evidence that inflammatory cues associated with fever-range thermal stress promote lymphocyte extravasation across HEVs of lymphoid organs through a highly regulated lymphocyte-endothelial-interleukin-6 (IL-6) biological axis. The potential for using thermally-based strategies to improve lymphocyte delivery to the tumor microenvironment during T cell-based immunotherapy will also be discussed.  相似文献   

6.
Carcinoembryonic antigen (CEA) has been reported to promote the metastatic potential in some experimental tumors. Adhesion molecules are known to play an important role in the process of metastasis. Cytokines, including interleukin 1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), which are produced by Kupffer cells, induce endothelial cells to express adhesion molecules. As a result, the present study was designed to investigate whether the interaction between CEA and Kupffer cells accelerated the metastatic potential of tumors in the liver. Kupffer cells isolated from the liver of male BALB/c mice were cultured with CEA, either with or without the addition of a cytokine inhibitor. The levels of IL-1beta and TNF-alpha were examined in a culture medium. An adhesion assay of colon cancer cell lines to human umbilical vein endothelial cells was also performed. When CEA was added to the Kupffer cell culture medium, cytokines were produced. Elevated levels of cytokines appeared to lead to increased rates of adhesion of cancer cells to endothelial cells. However, these phenomena were blocked by the addition of cytokine inhibitors. CEA stimulated Kupffer cells to produce cytokines. An elevated number of cytokines have been proven to promote the expression of adhesion molecules in endothelial cells. These processes are therefore considered to contribute to the metastasis of malignant cells to the liver. These results suggest that cytokine inhibitors may therefore play an important role in the inhibition of hepatic metastasis.  相似文献   

7.
The processes of lymphocyte-endothelial cell interaction and the in vitro assays employed in their study are the subjects of this review. In motility assays in porous filters and gel matrices, it has been shown that lymphocyte migration can be modulated by interleukin-2 (IL-2), IL-3, IL-4, IL-6, and IL-8. Cytokines can also modulate lymphocyte-endothelial adhesion. Endothelial intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) are induced or upregulated by IL-1 or tumor necrosis factor. In addition, interferon-gamma upregulates ICAM-1, and IL-4 can induce VCAM-1. The roles of these cytokines and adhesion molecules in transendothelial migration may be studied in assays in which lymphocytes penetrate layers of cultured endothelial cells. These models can distinguish lymphocyte adhesion from subsequent migration. Using such models, we and others have obtained evidence that both lymphocyte function-associated antigen-1 (LFA-1)/ICAM-1 and very late activation antigen 4 (VLA-4)/VCAM-1 interactions mediate lymphocyte adhesion to endothelial cells, but that LFA-1/ICAM-1 interactions play a greater role in transendothelial migration.  相似文献   

8.
In this experimental study, the influence of surgery-induced proinflammatory cytokines on tumor recurrence in the lung was investigated. A reproducible human in vitro assay was developed to study the adhesion of HT29 colon carcinoma cells to monolayers of microvascular endothelial cells of the lung (HMVECs-L) or human umbilical venous endothelial cells (HUVECs). Preincubation of HMVECs-L with maximally active concentrations of IL-1beta and TNF-alpha, but not with IL-6, resulted in at least 250% adhesion compared to control adhesion (p 相似文献   

9.
BACKGROUND AND AIM: The activation of NF-kappaB induces production of inflammatory cytokines and up regulation of endothelial cell adhesion molecules (ECAM). ECAM (e.g., E-selectin, VCAM-1 and ICAM-1) associates to the recruitment of leukocytes into tissue exposed to inflammatory situation. In this study, we investigated the effects of hyperthermia on the activation of NF-kappaB and the up regulation of E-selectin and VCAM-1 in human endothelial cells stimulated by TNF-alpha. METHODS: Human arterial endothelial cells (HAEC) were pretreated with hyperthermia for 60 min at 42 degrees C, followed by incubation at 37 degrees C in a passively cooled incubator, before TNF-alpha stimulation. To assess the effects of hyperthermia on TNF-alpha-induced up regulation of ECAM and TNF-alpha-induced activation of NF-kappaB, we measured ECAM by ELISA, and evaluated the activation of NF-kappaB by Western blotting after TNF-alpha stimulation. The accumulation of HO-1, Hsp70 and IkappaBalpha in hyperthermia-treated HAEC was also assessed by Western blotting. To investigate the role of Hsp70, we treated HAEC with geranylgeranylacetone (GGA, Hsp70 inducer) 2 h before hyperthermia, and then measured ECAM in TNF-alpha-stimulated HAEC by ELISA. RESULTS: Pretreatment of hyperthermia reduced TNF-alpha-induced up regulation of E-selectin and VCAM-1. In addition, accumulation of Hsp70, HO-1 and IkappaBalpha protein were up-regulated after hyperthermia. Furthermore, Western blotting analysis revealed that pretreatment of hyperthermia attenuated TNF-alpha-induced translocation of p65 into the nuclei of HAEC. Moreover, GGA enhanced Hsp70 accumulation induced by hyperthermia. Hyperthermia pretreatment combined with GGA induced further inhibition of TNF-alpha-induced up regulation of ECAM when compared with hyperthermia alone. CONCLUSION: Pretreatment of hyperthermia blocks TNF-alpha-induced NF-kappaB activation, resulting in the inhibition of ECAM up regulation in HAEC.  相似文献   

10.
In this study we examined the levels of IL-1 alpha, IL-1 beta, IL-2, IL-6, TNF-alpha and sIL-2R in the sera and culture supernatants of PHA-stimulated lymphocytes from a series of 90 cancer patients. The expression of the IL-2R p55 chain (alpha subunit) on PHA-stimulated lymphocytes was also evaluated together with the blastogenic response of peripheral blood mononuclear cells (PBMC) to PHA, PHA plus rIL-2 and rIL-2 alone. Ninety cancer patients (70 men and 20 women; mean age 57.8 years, range 27-80) with advanced solid malignancies at different sites were studied. The lymphocyte blastogenic response to PHA was significantly lower in cancer patients than in normal individuals. The proliferative response to rIL-2 alone was also significantly depressed in cancer patients. The frequency of CD25(+) PHA-stimulated lymphocytes from cancer patients was not significantly different from that of the control group. The serum values for IL-1 alpha, IL-1 beta, IL-6 and sIL-2R were significantly higher in cancer patients than in controls, while the serum level of IL-2 was within the normal range. The levels of sIL-2R released in the supernatant of PHA-stimulated PBMC of cancer patients were significantly lower than those of the control group. However, the levels of IL-1 alpha, IL-1 beta, IL-2, IL-6 and TNF-alpha, in the supernatants of PHA-stimulated PBMC of cancer patients were in the same range as those of the control group. These results suggest that the observed immune-deficiency in cancer patients cannot be explained on the basis of a defective production of key immunoregulatory cytokines since the lymphocytes from cancer patients produced physiological amounts of cytokines. We suggest that the observed defective cell-mediated immunity may be due to a defect in transmembrane signalling by the cytokines.  相似文献   

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12.
Bone marrow (BM) environment is thought to support the growth of myeloma cells and thus to play an important role in the pathogenesis of multiple myeloma (MM). Because interleukin-6 (IL-6) is an essential growth factor in MM, we have examined the effects of two myeloma cell lines (U266 and ARH-77) on the IL-6 production by BM stromal cells in a co-culture system. These cell lines strongly stimulate the IL-6 production and IL-6 triggering was partially dependent on physical contact between lines and stroma. The percentages of cell adhesion to stromal layers were 39% and 25% respectively for ARH77 and U266 cell lines. Inhibition studies with blocking monoclonal antibodies showed the importance of CD49d/CD106 and CD11a/CD54 interactions in the stimulation of IL-6 production by stromal cells. However, cell-to-cell contact was not an absolute requirement for IL-6 production. Cytokines, of which TNF-alpha and IL-1beta produced by MM or accessory cells, were also able to stimulate IL-6 production by fibroblasts and show additive effects. In adhesion assays, TNF-alpha and IL-1beta were able to increase the adhesion of MM cells to stromal cells. CD54 was upregulated by IL-1beta, TNF-alpha or a contact with MM cells while CD106 expression was not, suggesting only a functional change of this molecule. However, the role of monoclonal antibodies, directed against these factors, confirmed the role of TNF-alpha in the IL-6 production by stromal cells, while any IL-1beta intervention was not shown in our co-culture system. IL-6 favoured and maintained adhesion of MM cells to stromal cells spontaneously since its reintroduction in the favoured co-culture system restored their decreased adhesion observed on a glutaraldehyde fixed stromal layer. Overall our data suggest a functional overlap between cytokines and adhesion molecules for the paracrine IL-6 production.  相似文献   

13.
Microvascular endothelial cells play a critical role in tumor progression and metastasis by forming capillary networks that encourage tumor growth and by promoting the attachment of circulating tumor cells to the vascular wall of distant tissues. Efforts to study the molecular mechanisms that mediate these complex processes in different anatomical compartments have been impeded by difficulties in the isolation and propagation of endothelial cells from different organs. To overcome these limitations, we used two-color flow cytometry to identify and select microvascular endothelial cells from primary cultures obtained from different organs of mice whose tissues harbor a temperature-sensitive SV40 large T antigen (H-2K(b)-tsA58 mice; ImmortoMice). The selection strategy targeted cell populations expressing the inducible endothelial cell adhesion molecules, E-selectin and VCAM-1, and proved successful in generating microvascular endothelial cell lines from a number of different organs. When cultured under permissive temperatures (33 degrees C), individual cell lines displayed doubling times consistent with endothelial cells possessing an angiogenic phenotype. The transfer of endothelial cells to nonpermissive temperatures (37 degrees C) resulted in cell differentiation and the induction of a quiescent state. Established cell lines exhibited several inherent endothelial properties, including the expression of constitutive and inducible levels of endothelial cell adhesion molecules E-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, internalization of acetylated low-density lipoprotein, and formation of loop structures on Matrigel surfaces. The immortalized endothelial cell lines established from H-2K(b)-tsA58 mice provide, for the first time, a cell culture system to examine factors regulating angiogenesis and tumor cell arrest in different organ systems.  相似文献   

14.
Downregulating the leukocyte adhesion molecules expressed by endothelial cells that line tumor blood vessels can limit the entry of immune effector cells into the tumor mass, thereby contributing to tumoral immune escape. Egfl7 (also known as VE-statin) is a secreted protein specifically expressed by endothelial cells in normal tissues and by cancer cells in various human tumors. High levels of Egfl7 correlate with higher tumor grade and poorer prognosis. Here we show that expression of Egfl7 in breast and lung carcinoma cells accelerates tumor growth and metastasis in immunocompetent mice but not in immunodeficient mice. Tumors expressing Egfl7 were infiltrated relatively poorly by immune cells and were characterized by reduced levels of immunostimulatory cytokines [IFN-γ, interleukin-12 (IL-12)] and fewer endothelial adhesion molecules [intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1)]. In vitro studies revealed that Egfl7 inhibited the expression of leukocyte adhesion molecules by endothelial cells, preventing lymphocyte adhesion. In contrast, Egfl7 did not exert any effects on immune cell activation. Human breast cancer lesions expressing high levels of Egfl7 also expressed less ICAM-1 and VCAM-1 in their blood vessels, also indicating an inverse correlation between expression levels of Egfl7 and IFN-γ. Thus, Egfl7 expression in tumors promotes tumor progression by reducing the expression of endothelial molecules that mediate immune cell infiltration. Our findings highlight a novel mechanism through which tumors escape immune control.  相似文献   

15.
Freshly isolated tumor-infiltrating lymphocytes (TIL) and lymph node lymphocytes (LNL) in patients with head and neck cancer (HNC) often have low or undetectable functional responses. Because impaired ability of these cells to produce cytokines could be responsible for their functional incompetence, spontaneous and in vitro-induced production of interleukin-2 (IL2), interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and interferon gamma (IFN-gamma) by TIL, LNL from tumor-free as well as tumor-involved lymph nodes (LN), and peripheral blood lymphocytes (PBL) were measured. Although TIL or PBL of patients with HNC produced IL-1 beta and TNF-alpha spontaneously or after in vitro activation, LNL did not produce measurable levels of these cytokines. LNL also produced lower levels of IFN-gamma than PBL. In situ hybridization for cytokine mRNA performed with tumor tissues, and LN of patients with HNC showed that TIL as well as LNL localized in the immediate proximity of the tumor were activated, as evidenced by the expression of mRNA for IL2, IFN-gamma, IL-1 beta, TNF-alpha, and both alpha- and beta-chains of the IL2 receptor. In addition, many LNL located next to the tumor expressed mRNA for transforming growth factor-beta (TGF-beta). In contrast, LNL not adjacent to the tumor in involved LN, as well as those in tumor-uninvolved LN, did not express mRNA for cytokines or IL2 receptor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Bispecific antibody (BsMAb) BIS-1 has been developed to redirect the cytolytic activity of cytotoxic T lymphocytes (CTL) to epithelial glycoprotein-2 (EGP-2) expressing tumour cells. Intravenous administration of BIS-1 F(ab')2 to carcinoma patients in a phase I/II clinical trial, caused immunomodulation as demonstrated by a rapid lymphopenia prior to a rise in plasma tumour necrosis factor-alpha and interferon-gamma levels. Yet, no lymphocyte accumulation in the tumour tissue and no anti-tumour effect could be observed. These data suggest a BsMAb-induced lymphocyte adhesion to blood vessel walls and/or generalized redistribution of the lymphocytes into tissues. In this study, we describe the effects of BIS-1 F(ab')2 binding to peripheral blood mononuclear cells (PBMC) on their capacity to interact with resting endothelial cells in vitro. Resting and pre-activated PBMC exhibited a significant increase in adhesive interaction with endothelial cells when preincubated with BIS-1 F(ab')2, followed by an increase in transendothelial migration (tem). Binding of BIS-1 F(ab')2 to PBMC affected the expression of a number of adhesion molecules involved in lymphocyte adhesion/migration. Furthermore, PBMC preincubated with BIS-1 F(ab')2 induced the expression of endothelial cell adhesion molecules E-selectin, VCAM-1 and ICAM-1 during adhesion/tem. These phenomena were related to the CD3 recognizing antibody fragment of the BsMAb and dependent on lymphocyte-endothelial cell contact. Possibly, in patients, the BIS-1 F(ab')2 infusion induced lymphopenia is a result of generalized activation of endothelial cells, leading to the formation of a temporary sink for lymphocytes. This process may distract the lymphocytes from homing to the tumour cells, and hence prevent the occurrence of BIS-1 F(ab')2 - CTL-mediated tumour cell lysis.  相似文献   

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19.
Rheumatoid arthritis is a multisystem disease with underlying immune mechanisms. Osteoarthritis is a debilitating, progressive disease of diarthrodial joints associated with the aging process. Although much is known about the pathogenesis of rheumatoid arthritis and osteoarthritis, our understanding of some immunologic changes remains incomplete. This study tries to examine the numeric changes in the T cell subsets and the alterations in the levels of some cytokines and adhesion molecules in these lesions. To accomplish this goal, peripheral blood and synovial fluid samples were obtained from 24 patients with rheumatoid arthritis, 15 patients with osteoarthritis and six healthy controls. The counts of CD4 (+) and CD8 (+) T lymphocytes were examined using flow cytometry. The levels of some cytokines (TNF-alpha, IL1-beta, IL-10, and IL-17) and a soluble intercellular adhesion molecule-1 (sICAM-1) were measured in the sera and synovial fluids using enzyme linked immunosorbant assay. We found some variations in the counts of T cell subsets, the levels of cytokines and sICAM-1 adhesion molecule between the healthy controls and the patients with arthritis. High levels of IL-1beta, IL-10, IL-17 and TNF-alpha (in the serum and synovial fluid) were observed in arthritis compared to the healthy controls. In rheumatoid arthritis, a high serum level of sICAM-1 was found compared to its level in the synovial fluid. A high CD4(+)/CD8(+) T cell ratio was found in the blood of the patients with rheumatoid arthritis. In rheumatoid arthritis, the cytokine levels correlated positively with some clinicopathologic features. To conclude, the development of rheumatoid arthritis and osteoarthritis is associated with alteration of the levels of some cytokines. The assessment of these immunologic changes may have potential prognostic roles.  相似文献   

20.
Purpose: Exposure to increased environmental temperatures is commonly used as a non-pharmacological treatment modality in ankylosing spondylitis (AS). We aimed to investigate systemic immunological effects of moderate whole body hyperthermia in patients with AS compared to healthy control subjects. Materials and methods: Ten healthy control subjects and six AS patients underwent whole body hyperthermia treatment with 38.7–39?°C body core temperature over 60?min. Numbers of polymorphonuclear leucocytes and lymphocyte subsets, plasma concentrations of several acute phase reactants and cytokines, and gene expression levels of toll-like receptor 4 (TLR-4), interleukin 10 (IL-10) and heat shock protein beta 1 (HSPB1) were determined during and up to 24?h after treatment. Results: TLR-4, IL-10 and HSPB1 gene expression increased significantly up to 3?h post treatment, with an earlier, higher and more pronounced increase of IL-10 in patients with AS. An increase of natural killer cells and CD8+ T lymphocytes was noted during active heating, with a subsequent decrease up to 2 h after treatment. CD4+ T lymphocytes showed a short increase during active treatment in AS patients, while decreasing immediately after start of treatment in control subjects. Neutrophil granulocytes increased significantly up to 3?h after treatment, monocytes and B lymphocytes remained unchanged. Likewise, no significant changes were found concerning systemic cytokine concentrations and acute phase reactants. Conclusions: Our data support the concept of systemic immunological effects of moderate whole body hyperthermia in patients with AS.  相似文献   

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