Elevated levels of soluble adhesion molecules in sera and BAL fluid of individuals infected with human T-cell lymphotropic virus type 1

STUDY OBJECTIVE: T-lymphocytic alveolitis and increased levels of interleukin-2 receptor-alpha (CD25)-bearing T cells in the BAL fluid (BALF) of human T-cell lymphotropic virus type 1 (HTLV-1) carriers have been reported. Several chemokines and adhesion molecules may contribute to the accumulation of T lymphocytes in the lungs of HTLV-1 carriers. To clarify the correlation between adhesion molecules and HTLV-1-associated pulmonary disorders, we compared the distribution of T-lymphocyte subsets and soluble adhesion molecules, including soluble intercellular adhesion molecule (sICAM)-1, soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble L-selectin (sL-selectin), soluble E-selectin (sE-selectin), and soluble P-selectin (sP-selectin), in BALF and peripheral blood, between HTLV-1 carriers and noninfected healthy subjects. DESIGN: Flow cytometric analysis with monoclonal antibodies to cell-surface antigens was used to identify T-lymphocyte subsets in BALF samples from HTLV-1 carriers (n = 13) and noninfected healthy control subjects (n = 10). The levels of various soluble adhesion molecules in serum and in BALF were estimated by enzyme-linked immunosorbent assay. RESULTS: Higher percentages of CD3+ cells, CD3-expressing human leukocyte antigen-DR antigen, and CD3+CD25+ cells were detected in the BALF of HTLV-1 carriers than in that of noninfected control subjects. The concentrations of sICAM-1, sVCAM-1, sL-selectin, SE- selectin, and sP-selectin in the sera of patients were significantly higher than those in noninfected healthy control subjects. The concentration of sICAM-1 in the BALF of patients was significantly higher than that in noninfected healthy control subjects, and the concentration of sICAM-1 correlated well with the percentage of CD3+CD25+ cells. CONCLUSION: The concentrations of adhesion molecules in the sera of and sICAM-1 in the BALF of HTLV-1 carriers were significantly higher than those in noninfected individuals, and the concentration of sICAM-1 correlated well with the percentage of CD3+CD25+ cells in BALF. Our results suggest a possible interaction between activated T cells bearing CD25 and soluble adhesion molecules, especially sICAM-1, which may contribute to the pulmonary involvement in HTLV-1 carriers.     

Soluble form of fas and fas ligand in BAL fluid from patients with pulmonary fibrosis and bronchiolitis obliterans organizing pneumonia

STUDY OBJECTIVES: The Fas-Fas ligand (FasL) pathway is a representative system of apoptosis-signaling receptor molecules. We previously described that this pathway may play an important role in the pathogenesis of fibrosing lung diseases. In this study, we hypothesized that soluble form of Fas (sFas) and FasL (sFasL) may also be associated with this disorder. MEASUREMENTS AND RESULTS: We measured sFas and sFasL levels in BAL fluid (BALF) from patients with idiopathic pulmonary fibrosis (IPF), interstitial pneumonia associated with collagen vascular diseases (CVD-IP), and bronchiolitis obliterans organizing pneumonia (BOOP), using enzyme-linked immunosorbent assay. BALF from all patients was obtained before prednisolone therapy. sFasL levels were relatively increased in IPF patients (p = 0.084), and significantly increased in CVD-IP patients (p < 0.05) and BOOP patients (p < 0.05), compared with control subjects. BALF sFasL levels were elevated in the IPF or CVD-IP subgroups with an indication for prednisolone therapy, compared with those without an indication for therapy. The BALF sFasL level in IPF patients was correlated with the number of total cells and lymphocytes. The BALF sFasL level in BOOP patients was relatively or significantly correlated with the number of total cells or lymphocytes, respectively. The BALF sFas level was significantly increased in BOOP patients, but not in IPF or CVD-IP patients. CONCLUSIONS: We conclude that BALF sFasL levels may be associated with the accumulation of inflammatory cells and reflect the degree of lymphocyte alveolitis in IPF. The elevation of sFasL may be associated with the deterioration of IPF and CVD-IP. The elevation of the BALF sFas level may abrogate the cytotoxicity of FasL in BOOP patients, which may be associated with better prognosis of BOOP, compared with IPF or CVD-IP.     

Analysis of cytotoxic T lymphocytes and Fas/FasL in Japanese patients with non-small cell lung cancer associated with HLA-A2

PURPOSE: In recent years, the use of immunotherapy for malignant tumors has been proposed. To explore the significance of immunotherapy for lung cancer, we examined two systems : the HLA class I and cancer-reactive CTL system, and the Fas-FasL system. METHODS: HLA class I (HLA-A, -B, and -C) antigens were determined in 61 patients with lung cancer and in 30 healthy controls. The HLA class I phenotype was investigated by serological techniques. HLA-A2 alleles were investigated by polymerase chain reaction sequence-specific primer analysis. We analyzed lymphocytes isolated from 61 patients with two-color surface labeling and flow cytometry. Furthermore, we analyzed sFas and sFasL expression by enzyme-linked immunosorbent assay (ELISA). We also examined lung cancer cell line-induced apoptosis of CD8(+) lymphocytes using confocal laser scanning microscopy. RESULTS: The HLA-A2 allele was observed in 27 of 61 patients with lung cancer. There were no differences in HLA-A2 allele classifications between lung cancer patients and controls. Thirty-six of the 61 lung cancer patients (57%) had elevated levels of sFas, and 16 of the 61 patients (26.2%) had elevated levels of sFasL. The sFas level of lung cancers with HLA-A2 was significantly higher than that of cancers without HLA-A2 ( P<0.01). This tendency was observed in every lung cancer tissue type, and the sFas levels of lung cancers with HLA-A2 associated significantly with the CTL levels of lung cancers with HLA-A2. Furthermore, compared to lung cancers without HLA-A2, CD8(+) T-cell levels were elevated in lung cancers with HLA-A2. In contrast, sFas levels of non-small cell lung cancers without HLA-A2 were higher than those in lung cancers with HLA-A2. In an in vitro experiment using lung cancer cell lines, we observed apoptosis of CD8(+) lymphocytes induced by lung cancer cells. Lung cancer-reactive CTLs are mobilized easily by restriction of HLA-A2, but this restriction is not always specific. In addition, FasL derived from lung cancer cells can induce apoptosis of CD8(+) T-cells, and the frequency of this phenomenon is increased in small cell lung cancers without HLA-A2. CONCLUSION: Our findings suggest that the effect of immunotherapy may be insufficient for non-small cell lung cancer without HLA-A2.     

The evaluation of soluble Fas and soluble Fas ligand levels of bronchoalveolar lavage fluid in lung cancer patients

Fas-Fas Ligand (FasL) is one of the major mediator system that activates programmed cell death. Cleavage of membranebound FasL by a metalloproteinase-like enzyme resulted in the formation of soluble FasL (sFasL). sFasL as well as the transmembrane form of FasL binds to Fas and transduces apoptotic signal in Fas-expressing cells. It's suggested that soluble Fas (sFas) and sFasL has an impact on tumor progress and immune escape feature of tumor cells from the host immune system. Since Fas antigen expression in the lungs has been localized to alveolar and bronchial epithelial cells, in this study we aimed to investigate the sFas (pg/mL) and sFasL levels (pg/mL) of bronchoalveolar lavage (BAL) fluid in lung cancer patients. Study population was consisted of 27 patients with lung cancer (mean age 62.9 +/- 10.7 years, 25 control subjects (mean age 47.9 +/- 13.9 years). BAL was performed under local anesthesia, on the unaffected lung of patients; either subsegments of right middle or lingula. BAL sFas and sFasL were evaluated by using ELISA method. The mean levels of sFas was 60.8 +/- 56.8 in lung cancer patient and 39.5 +/- 25.9 in control subjects (p> 0.05). The mean levels of sFasL was 51.6 +/- 39.2 in cancer patient and 41.2 +/- 27.4 in control subjects (p> 0.05). In conclusion, although we did not observe any significant difference between two groups, higher BAL levels of sFas and sFasL levels in lung cancer patients than control subjects, made us thought that apoptosis might have a role development and progression of lung cancer.     

Influence of levothyroxine treatment on serum levels of soluble Fas (CD95) and Fas Ligand (CD95L) in chronic autoimmune hypothyroidism

Fas/FasL-mediated apoptosis results in the destruction of thyrocytes in chronic autoimmune hypothyroidism (CAIH). In this study, we examined the serum levels of soluble Fas (sFas) and soluble sFas ligand (sFasL) in euthyroid patients with chronic autoimmune hypothyroidism, who were taking levothyroxine (euthyroid, LT4-CAIH), to investigate the possible role of thyroid hormone therapy in down-regulation of apoptotic factors. Fifty euthyroid patients with CAIH on levothyroxine (median of duration 36 months, range 6-228 months) were compared with 75 age- and sex-matched healthy individuals. Serum levels of soluble Fas and soluble Fas Ligand, autoantibodies to thyroid peroxide and thyroglobulin were measured using ELISA. Serum levels of sFas were significantly higher in the euthyroid, LT4-CAIH group [median 9.12 ng/ml, interquartile range (7.86-10.72 ng/ml)] than in the controls [6.11 ng/ml (5.60-6.81 ng/ml)] (P < 0.0001). Compared with controls [80.33 pg/ml (68.22-103.70 pg/ml)], the euthyroid, LT4-CAIH group [125.71 pg/ml (106.11-149.48 pg/ml)] had significantly higher levels of sFasL (P < 0.0001). In a chronological study, there was no significant correlation between sFas, sFasL, and the duration of levothyroxine therapy. In conclusion, normalization of serum sFas and sFasL levels cannot be achieved during levothyroxine treatment in patients with CAIH. It appears that levothyroxine therapy has no important effect on down-regulation of apoptotic factors in CAIH. Thus, like thyroid autoantibodies, monitoring of serum levels of sFas/sFasL is not indicated during thyroid hormone therapy.     

Serum concentration of sFas and sFasL in healthy HBsAg carriers, chronic viral hepatitis B and C patients

AIM: To estimate the amount of apoptosis among healthy HBsAg carriers, patients with chronic HBV infection treated with lamivudine and patients with chronic HCV infedJon treated with interferon alpha and ribavirin. Activity of apoptosis was evaluated by serum sFas/sFasL concentration measurement.Moreover dependence between apoptosis and HBV-DNA or HCV-RNA levels was studied.METHODS: Eighty-six persons were included into study: 34 healthy HBsAg carriers, 33 patients with chronic HBV infection and 19 patients with chronic HCV infection. Serum levels of sFas/sFasL were measured by ELISA assay. HBV-DNA and HCV-RNA were measured by RT-PCR assay. Levels of sFas/sFasL were determined before and 2 and 12 wk after therapy in patients with chronic hepatitis B and C infection.HBV-DNA or HCV-RNA was detected before treatment and 6 mo after treatment.RFSULTS: Twenty-four (71%) healthy HBsAg carriers showed HBV-DNA over 10^5/mL, which was comparable to the patients with chronic hepatitis B. Independently from HBV-DNA levels,the concentration of sFas among healthy HBsAg carriers was comparable to healthy persons. Among patients with chronic hepatitis B and C, the concentration of sFas was significantly higher in comparison to healthy HBsAg carriers and healthy persons. In chronic hepatitis B patients the concentration of sFas was decreased during lamivudine treatment. Among chronic hepatitis C patients the concentration of sFas was increased during IFN alpha and ribavirin treatment, sFasL was not detected in control group. Furthermore sFasL oo:urred more frequently in chronic hepatitis C patients in comparison to chronic hepatitis B patients.CONCLUSION: There are no correlations between apoptosis and HBV-DNA levels. However ther is an association between apoptosis and activity of inflammation in patients with chronic HBV infection. Apoptosis can be increased in patients with chronic hepatitis C by effective treatment which may be a result of apoptosis stimulation by IFN-α.     

Fas/Fas-Ligand pathway is impaired in patients with type 2 diabetes. Influence of hypertension and insulin resistance

OBJECTIVES: In type 2 diabetic patients with no cardiac history or symptoms, 1) to evaluate whether the soluble forms of Fas (sFas) and Fas-ligand (sFasL), involved in apoptosis, may be markers of silent coronary disease or related to hypertension or microangiopathic complications; 2) to examine the effect of short-term glycemic control on sFas and sFasL. METHODS: (1) sFas and sFasL were measured with the ELISA method in 44 asymptomatic diabetic patients, 33 with hypertension, and with a normal myocardial scintigraphy (n=14), with silent myocardial ischemia (SMI) and without (n=15) or with (n=15) significant coronary stenoses; and in 14 controls; (2) sFas and sFasL were measured in 15 poorly controlled diabetic patients before and after 7 days of CSII treatment. RESULTS: (1) sFas and sFasL differed in the four groups of patients (p=0.003 each). sFas was significantly higher in the patients with SMI without (p=0.035) and with coronary stenoses (p=0.002) than in the control group. sFasL was lower in the three groups of diabetic patients (p<0.05 each) than in control group. In the diabetic population, sFas correlated positively with hypertension (p=0.021), and sFasL negatively with hypertension (p=0.027) and HOMA index in the non-insulin treated patients (p=0.049); (2) sFas did not differ before or after CSII, and there was a marginal decrease in sFasL. CONCLUSION: Fas-mediated apoptosis is involved in type 2 diabetes and might be associated with hypertension and/or its vascular consequences. sFasL might be affected by insulin resistance. sFas and sFasL are not effective markers of SMI.     

Increased levels of soluble Fas in serum from diabetic patients with neuropathy.

OBJECTIVE: The aim of this study was to investigate circulating soluble Fas (sFas) and Fas ligand (sFasL), two transmembrane glycoproteins involved in apoptosis, in the serum of diabetic patients.MATERIAL AND METHODS: We assessed sFas and sFasL serum levels in normal controls (n=15), and in both 42 diabetic patients without complications, or with predominant retinopathy or neuropathy, using sFas and sFasL specific ELISA method.RESULTS: sFasL serum levels were less than 0.1 ng/ml in normal controls and in each group of diabetic patients. In diabetic patients with a predominant neuropathy, sFas serum levels were significantly increased not only when compared with normal controls (13.5 +/- 3.6 ng/ml vs 7.1 +/- 1.1 ng/ml, p<0.001), but also when compared with patients without complications (vs 9.1 +/- 1.8 ng/ml, p<0.001) or with a predominant retinopathy (vs 8.7 +/- 1.9 ng/ml, p<0.001).CONCLUSIONS: These preliminary data suggest that a dysregulation of the Fas system in peripheral neuronal cells may be involved in the increase of sFas observed in diabetic patients with neuropathy.     

可溶性Fas,可溶性Fas配体与细胞因子在1型糖尿病发病中的意义

目的　研究可溶性Fas(sFas)和可溶性Fas配体(sFasL)与细胞因子在1型糖尿病发病中的作用。方法　32名1型糖尿病患者和20名正常人的血清,采用夹心BAS-ELISA法分别检测sFas,sFasL,γ干扰素(IFN-γ)及白细胞介素-1(IL-1)含量。结果　1型糖尿病血清中sFas,IFN-γ及IL-1含量分别为(1　　546±685,1　　074±451与1　　406±721)ng/L,显著高于正常组;sFasL为(211±73)mg/L,低于正常组但差异无显著性。在1型糖尿病患者中高浓度sFas伴高IFN-γ者共12例,低浓度sFas伴低IFN-γ者共9例。结论　1型糖尿病患者血清中的sFas,IFN-γ及IL-1高于正常人,sFas与IFN-γ浓度呈正相关(r=0.79,P＜0.05)。对1型糖尿病患者血清进行sFas,IFN-γ及IL-1等检测可作为反映胰岛细胞病变的辅助指标,有助于对疾病的诊断与治疗。     

Increased circulating levels of soluble Fas ligand are correlated with disease activity in patients with fibrosing lung diseases

OBJECTIVE: The Fas-Fas ligand (FasL) pathway is one of the important apoptosis-signalling molecule systems. We previously determined that this pathway may be involved in the pathogenesis of fibrosing lung diseases. In the present study, we evaluated the clinical significance of the levels of soluble forms of Fas (sFas) and FasL (sFasL) in serum from patients with fibrosing lung diseases. METHODOLOGY: We measured sFas, sFasL, KL-6 (a measure of alveolar type II cell damage), surfactant protein D (SP-D), and surfactant protein A (SP-A) levels in serum from 35 patients with idiopathic pulmonary fibrosis (IPF), 17 patients with interstitial pneumonia associated with collagen vascular diseases (CVD-IP), and 13 normal healthy controls using enzyme-linked immunosorbent assays (ELISA). RESULTS: The serum levels of sFasL were significantly increased in patients with active IPF and CVD-IP, compared with those with inactive disease and controls. There was no significant difference in sFasL levels between patients with inactive disease and controls. Serum sFasL levels were significantly correlated with lactate dehydrogenase and KL-6 levels in IPF. The decrease in sFasL levels following corticosteroid therapy was not correlated with the clinical course of IPF. There was no significant difference in serum sFas levels between IPF or CVD-IP patients and controls. CONCLUSIONS: Although further studies need to be performed on a large number of patients with histologically proven IPF or CVD-IP, it would seem that serum sFasL levels may reflect the activity of IPF and CVD-IP.     

sFas与sFasL在自身免疫疾病中的意义

目的　研究sFas与sFasL在系统性红斑狼疮 (SLE)等自身免疫疾病中的意义及抗单链DNA(ssDNA)抗体与sFas和sFasL介导凋亡的相关性。方法　采用夹心ELISA方法检测 31例SLE病人 ,32例类风湿关节炎 (RA)病人 ,2 0例 1型糖尿病 (IDDM )病人及 5例多发性硬化病 (MS)病人血清中sFas与sFasL含量及抗ssDNA抗体水平。结果　在SLE、RA、IDDM及MS患者血清中的sFas含量 (pg/ml)分别为 2 881± 16 5 3 ,988± 6 96 ,135 2± 413 ,15 40± 5 6 6 ,明显高于正常对照 (P <0 0 0 2 ) ,SLE病人sFas含量高于RA ,MS ,IDDM病人。SLE、RA患者血清sFasL含量 (pg/ml)分别为5 35± 431、12 38± 1184,明显高于正常对照 (P <0 0 2 ) ,MS、IDDM患者血清sFasL含量 (pg/ml)分别为 2 5 1± 140 ,2 11± 73 ,低于正常对照 (P >0 0 5 )。在SLE、RA病人中 ,高浓度sFasL者伴有高浓度sFas。在SLE病人中 ,所有抗ssDNA抗体阳性者均伴有高浓度sFas,所有抗sFas阴性者 ,ssDNA抗体也为阴性。结论　在SLE等疾病中sFas水平明显高于正常人 ,可作为疾病进展与治疗效果的判断指标。抗ssDNA抗体与sFas具有关联性。sFas与sFasL在疾病中的相互作用及动态变化有待进一步研究     

Increased soluble Fas in HIV-infected hemophilia patients with CD4+ and CD8+ cell count increases and viral load and immune complex decreases

Previous studies interpreted increases of soluble Fas (sFas) in the plasma during disease progression in HIV-infected patients as evidence of increased apoptosis of CD4(+) lymphocytes. We studied whether sFas and sFas ligand (sFasL) plasma levels are associated with CD4(+) and CD8(+) lymphocyte counts, plasma viral load, and IgM, IgG, C3d, and gp120 complexes on circulating CD4(+) blood lymphocytes in long-term surviving HIV-infected hemophilia patients, most of whom were receiving HAART. Twenty-six hemophilia patients who were infected with HIV in the early 1980s were investigated in 1997, 1998, and 1999. HAART was initiated in 1996 and 1997 in most patients. Lymphocyte subpopulations and immune complex-coated CD4(+) lymphocytes in the blood were investigated by flow cytometry, plasma viral load (HIV-1 mRNA copies/ml plasma) was tested with HIV-1 QT Nuclisens kits, sFas (ng/ml) and sFasL (ng/ml) plasma levels were measured with MBL ELISA kits, and the in vitro response of patient lymphocytes was tested in cell cultures. During the period from 1997 to 1999 we observed an increase in sFas plasma levels (p = 0.003) as well as in CD4(+) (p = 0.004) and CD8(+) (p = 0.023) cell counts; a decrease in IgG (p = 0.047), C3d (p = 0.024), and gp120 (p = 0.001)-coated CD4(+) lymphocytes in the blood; and a decrease in the number of impaired mitogen stimulation assays (p = 0.013). sFas was negatively associated with viral burden (r = -0.662, p = 0.0002) as well as with CD4(+)IgM(+) (r = -0.554, p = 0.004), CD4(+)IgG(+) (r = -0.431, p = 0.031), CD4(+)C3d(+) (r = -0.551, p = 0.041), and CD4(+)gp120(+) (r = -0.430, p = 0.041) blood lymphocytes, CD8(+)DR(+) cell counts (r = -0.700, p = 0.016), and impaired in vitro responses of patient lymphocytes to PHA (r = -0.475, p = 0.016). sFasL was negatively associated with total lymphocyte counts (r = -0.433, p = 0.027), as well as with absolute numbers of CD3(+) (r = -0.492, p = 0.011) and CD8(+) (r = -0.432, p = 0.027) cells. We conclude that, contrary to expectations, sFas plasma levels increased in long-term surviving HIV-infected hemophilia patients receiving HAART, concomitant with increases in CD4(+) and CD8(+) cell counts. Increased sFas may reflect the growing pool of T lymphocytes that recovers because of a decreasing viral burden and a decreasing immune complex load of CD4(+) lymphocytes.     

Circulating soluble Fas ligand correlates with disease activity in Graves' hyperthyroidism

Apoptosis of thyrocytes may play an important role in the pathogenesis of autoimmune thyroiditis. Meanwhile, the Fas/Fas ligand (FasL) apoptosis pathway has received much attention in physiological homeostasis and immune regulation in various thyroid diseases, including Graves' hyperthyroidism (GD). FasL is a type II membrane protein of the tumor necrosis factor family, and induces apoptosis when it binds to Fas. Soluble FasL (sFasL) may also exert cytotoxic activity against Fas-expressing cells by producing trimerization of Fas molecule, but soluble Fas (sFas) is an apoptotic inhibitor. To determine the role of circulating sFas/sFasL in modulating disease activity of GD, we examined the circulating levels of sFas/sFasL in GD patients with various levels of anti-thyrotropin-stimulating hormone (TSH) receptor antibodies (TRAb). Serum samples were obtained from 22 consecutive untreated hyperthyroid GD patients with higher TRAb level (63.8% +/- 12.5%, group I) and 22 treated euthyroid GD patients, who were in a state of disease remission, with lower TRAb level (7.9% +/-5.9%, group II). The levels of sFas were significantly higher in group I (1.56 +/- 0.26 ng/mL) than in group II (0.76 +/- 0.26 ng/mL, P <.01). The levels of sFasL were also significantly higher in group I patients (0.153 +/- 0.018 ng/mL) than in group II patients (0.126 +/- 0.012 ng/mL, P <.01). A significant correlation was found between sFasL levels and TRAb activity in all GD patients (r = 0.69, P <.01). Because changes in sFasL levels and TRAb levels occur in parallel, increased serum sFasL in patients with GD may contribute to homeostasis in the thyroid. Serum sFasL may be considered to be a candidate marker for evaluating disease aggression or regression in GD.     

Relationship between HBxAg and Fas/FasL in patients with hepatocellularcarcinoma

AIM To assess the relationship between HBV X-gene, X-gene product and Fas/ FasL which mediatehepatocellular apoptosis in patients with hepatocellular carcinoma.METHODS Tissue from 34 patients with hepatocellular carcinoma was tested for the expression of HBxAg.Quantitative ELISA assay was used to detect sFas; and sFasL and PCR were used to detect the HBV X-genein sera from 30 patients with hepatocellular carcinoma, 32 patients with liver cirrhosis and 20 normalcontrols.RESULTS The positive expression of HBxAg, Fas and FasL in carcinoma tissue was 97.06%, 85.29% and100%, respectively. The positive signal was mainly presented in the plasma, and all of these three positivestaining may appear in the same area. Redit analysis showed that there was no significant difference amongthese three positive staining (P >0.05). The mean levels of sFas in sera from hepatocellular carcinoma, livercirrhosis and normal controls were 722.97±321.12, 801.90±419.94 and 224.07±148.23, respectively,showing that sFas levels in patients with hepatocellular carcinoma and liver cirrhosis were significantlyelevated than that in normal controls (P < 0.0l). The mean levels of sFasL in sera from hepatocellularcarcinoma, liver cirrhosis and normal controls were 152.27±7.99, 162.97±12.40 and 154.99 ± 6.96,showing that sFasL level in patients with liver cirrhosis was significantly higher than that in patients withhepatocellular carcinoma and normal controls (P< 0.01). HBV X-gene was found to be positive in sera of30% patients with hepatocellular carcinoma; HBV X-gene was found to be positive in sera of 43.75% ofpatients with liver cirrhosis. There was no significant difference in sFas/sFasL level between HBV X-genepositive patients and HBV X-gene negative patients (P >0.05).CONCLUSION The expression of HBxAg and Fas/FasL in the tissue of hepatocellular carcinoma seemed tobe almost the same, but relation between cause and effect is unclear. The detection of sFas and sFasL inpatient sera may reflect the state of apoptosis mediated by Fas/FasL system. Our data showed that HBV X-gene expression in sera seemed to have no relation to sFas/sFasL level; however, these data also suggestedthat some patients with negative HBsAg in sera might have integrated HBV X-gene in liver tissues, andtherefore X-gene is detectable in those patient sera.     

Elevation of soluble Fas and soluble Fas ligand in reactive macrophage activation syndromes

Derailed T-cell activation can give rise to life-threatening macrophage activation, the final common pathway of the different forms of reactive macrophage activation syndromes (rMAS). Besides inappropriate activation of the immune system, impaired termination of immune responses might be another mechanism leading to rMAS. The Fas (CD95)/Fas ligand (CD95 ligand) system functions in turning off immune responses by executing activation-induced cell death (AICD). Soluble Fas (sFas) and Fas ligand (sFasL) can interfere with their corresponding membrane-bound counterparts, qualifying them as potential parameters of impaired immune termination. Hence, sFas and sFasL were analyzed in sera of rMAS patients. We show that soluble Fas/CD95 (sFas) is elevated >2 SD over the mean of controls in all 8 rMAS episodes studied (mean 12.08 +/- 6.12 ng/mL, range 3.7-20.2; controls 2.46 +/- 0.49, range 1.5-2.9). sFasL was detected during five rMAS episodes (0.70 +/- 0.49 ng/mL, range 0.16-1.28; controls all below the limit of detection of 0.1). In addition, both parameters decrease during convalescence, reflecting clinical evolution. In conclusion, sFas seems to be consistently elevated during acute rMAS. sFasL is detected only in a subgroup of our adult rMAS patients extending the recent finding of sFasL elevation in a majority of children with macrophage activation syndromes (Hasegawa et al. Blood 1998;91(8):2793-2799). By interfering with AICD, sFas and sFasL might contribute to the pathogenesis of at least a subset of rMAS.     

Increased levels of soluble Fas receptor and Fas ligand in the cerebrospinal fluid of HIV-infected patients

Analyses of serum samples and blood cells have revealed a dysregulation of the Fas/Fas ligand (FasL) system during HIV infection, which may be related to disease progression. As Fas and FasL have been suggested to participate in brain injury in a variety of CNS disorders, the aim of this study was to determine (1) whether soluble Fas and FasL can be detected in cerebrospinal fluid (CSF) samples from HIV-infected patients, (2) whether levels of these molecules are related to disease progression, and (3) whether levels of sFasL are related to other laboratory findings. Soluble Fas was detected in 38 of 56 (68%) and soluble Fas ligand in 17 of 56 (30%) CSF samples from HIV-infected patients. CSF levels of both molecules correlated neither with the CSF-to-serum albumin ratio nor with corresponding serum concentrations. This finding suggests that they are at least in part produced intrathecally. Levels of both CSF sFas and sFasL correlated significantly and inversely with the blood CD4+ cell counts, suggesting that the intrathecal release of both molecules is increased during progression to advanced immunodeficiency.     

Serum levels of soluble molecules associated with evasion of immune surveillance: a study in biliary disease.

BACKGROUND: Biliary carcinoma cells produce the transmembrane proteins, Fas, FasL, and RCAS1. It has been demonstrated that the Fas/FasL and RCAS1 systems induce apoptosis of activated immune cells and that the soluble isoforms of these proteins (sFas, sFasL, and sRCAS1) also exhibit this function. METHODS: We measured serum levels of these soluble-types in patients with biliary disease by ELISA and investigated their clinical significance. RESULTS: In some cases of cholangitis and autoimmune biliary disease, serum sFasL values were over 0.1 ng/ml but the protein was undetectable in any patients with biliary carcinoma. sFas levels were significantly higher in the autoimmune disease (mean, 6.83 ng/ml) and cancer (mean, 6.42 ng/ml) groups than in the cholangitis group (mean, 4.23 ng/ml) and normal controls (mean, 2.93 ng/ml). However, the sFas values in malignancy did not correlate with the progression of clinical stage. The percentage positive for serum sRCAS1 was 9.7% in benign disease but was 63.4% in cancer. CONCLUSIONS: Our data suggest that serum sFasL in biliary disease may be derived predominantly from activated immune cells and not from cancer cells and that autoimmune biliary disease may be mediated by the Fas/FasL apoptotic system. sRCAS1 is highly tumor-specific and may be of value in the diagnosis of malignancy.     

Overexpression of HBxAg in hepatocellular carcinoma and its relationship with Fas／FasL system

AIM: To study the expression and serum level of HBxAg,Fas and FasL in tissues of HCC patients, and to assess the relationship between HBxAg and Fas/FasL system.METHODS: Tissues from 50 patients with HCC were tested for the expression of HBxAg, Fas and FasL by S-P immunohistochemistry. Serum levels of sFas/sFasL and HBsAg/HBeAg were measured by ELISA assay. HBV X gene was detected by PCR in serum and confirmed by automatic sequencing. Fifty cases of liver cirrhosis and 30 normal controls were involved in serum analysis.RESULTS: The expression of HBxAg, Fas and FasL in carcinoma tissues was 96 %, 84 % and 98 %, respectively.Staining of HBxAg, Fas and FasL was observed predominately in cytoplasms, no significant difference was found in intensity between HBxAg, Fas and FasL (P＞0.05). HBxAg, Fas and FasL might express in the same area of carcinoma tissues and this co-expression could be found in most patients with HCC. The mean levels of sFas in serum from HCC, cirrhosis and normal controls were 762.29±391.56 μg@ L-1 835.36±407.33 μg@L-1 and 238.27±135.29 μg@L-1. The mean levels of sFasL in serum from HCC, cirrhosis and normal controls were 156.36±9.61iμg@ L-1, 173.63±18.74 μg@L-1 and 121.96±7.83 μg@ L-1.Statistical analysis showed that both sFas and sFasL in HCC and cirrhosis patients were significantly higher than those in normal controls (P＜0.01). Serum HBV X gene was found in 32 % of HCC patients and ,46 % of cirrhotic patients.There was no significant relationship between serum level of sFas/sFasL and serum X gene detection (P＞0.05). Eight percent of HCC patients with negative HBsAg and HBeAg in serum might have X gene in serum and HBxAg expression in carcinoma tissues.CONCLUSION: Our data suggest that HBxAg and Fas/FasL system plays an important role in the development of human HCC. Expression of HBxAg can leads to expression of Fas/FasL system which and reverse apoptosis of hepatocellular carcinoma induced by FasL.     

Association among Fas expression in leucocytes,serum Fas and Fas‐ligand concentrations and hepatic inflammation and fibrosis in chronic hepatitis C

Background: Replication of the hepatitis C virus (HCV) in peripheral blood mononuclear cells (PBMC) may impair immune functions and establish persistent infection. The aim of this study was to assess the influence of HCV on PBMC and their susceptibility to apoptosis in relation to liver inflammation and fibrosis. Methods: Eighty‐one patients with chronic hepatitis C (CHC) were enrolled in this study. Flow cytometry was used to determine the amount of T cells (CD4⁺, CD8⁺), B cells (CD19⁺), monocytes (CD14⁺) and natural killer cells (CD16⁺) in the peripheral blood and the expression of CD95⁺ (CD95/APO‐1) in each subset. Serum concentrations of sFas and sFasL were assessed by the enzyme‐linked immunosorbent assay method. Results: An increased expression of Fas was observed in CD4⁺ and CD8⁺ cells in CHC. There was a more prominent expression of Fas on CD4⁺ cells in HCV genotype 1b in contrast to 3a. Increased Fas expression on CD4⁺ cells was seen in advanced stages of liver disease. Fas expression on monocytes was lower in advanced stages of liver inflammation and fibrosis. Serum sFas concentration was higher in CHC compared with the control group. There was an association between sFasL concentration and inflammatory activity in the liver. Serum sFasL concentration correlated positively with the mean intensity of fluorescence of the Fas receptor in CD4⁺ and CD8⁺ cells, granulocytes and monocytes. Conclusion: These findings indicate that there is an increased susceptibility of PBMC to apoptosis, which can be attributed to the constant contact of leucocytes with the inflamed liver tissue, or from direct HCV influence.     

Soluble Fas and Fas ligand in pregnancy: influence of hypertension

The pathophysiology of pregnancy-induced hypertension and preeclampsia may involve abnormalities in placentation and the Fas/Fas ligand system. Hypothesizing abnormal plasma Fas and Fas ligand in pregnancy-induced hypertension, we recruited 20 hypertensive pregnant women at mean week 15 and 29 at week 30: 18 were studied at both time points. Control groups were 20 normotensive pregnant women at week 20, 29 women at week 27, and 50 nonpregnant women. sFas and sFas ligand (sFasL) were measured by enzyme-linked immunosorbent assay (ELISA). The hypertensive women had lower sFasL at both stages of their pregnancy (P < .05). There were no differences in sFas. In 18 hypertensive pregnant women, sFasL fell from week 15 to week 29 (P < .03). We conclude that sFas and sFasL is unchanged in normal pregnancy. Hypertension in pregnancy is characterized by low sFasL, and levels fall from weeks 15 to 29. This may reflect differences in placentation in the differing physiological and pathological states.