Cytotoxic T cell (CTL) covers several subtypes, which are CD8+, CD4 and CD4-CD8-. CTL derives from T cell repertoire in lymphoid hematopoietic stem cells. It matures in thymus and is activated in peripheral lymphoid tissues. Effector CTL kills the target cells by 2 ways. One is apoptotic effect mediated by FasL-Fas pathway and the other one is cytolytic effect mediated by granzymes. CTL has aroused great attention due to its significance in anti-tumor and anti-virus.
Animals ; Fas Ligand Protein ; Humans ; Membrane Glycoproteins ; immunology ; Perforin ; Pore Forming Cytotoxic Proteins ; T-Lymphocytes, Cytotoxic ; immunology ; fas Receptor ; immunology

CD40 Ligand ; pharmacology ; HL-60 Cells ; drug effects ; Humans ; fas Receptor ; metabolism

OBJECTIVETo investigate the relationship of Fas mRNA and protein expression and apoptosis in human oral squamous cell carcinoma.

METHODSNorthern blot and flow cytometry (TUNEL method) were used to detect the expression of Fas mRNA and Fas protein, cell cycle and apoptotic level in oral squamous cell carcinoma. The relationship between Fas gene expression and OSCC apoptosis was analyzed statistically.

RESULTSFas mRNA and protein could be detected in all five normal oral mucosa specimens. There was positive correlation between expression of Fas mRNA/protein and cell differentiation as well as apoptosis in OSCC (P < 0.005).

CONCLUSIONThe expression of Fas gene was highly correlated with the differentiation and apoptosis in OSCC.

Apoptosis ; Carcinoma, Squamous Cell ; metabolism ; Humans ; Mouth Neoplasms ; metabolism ; fas Receptor ; metabolism

OBJECTIVE: To observe the expression of Fas receptor and ligand in human laryngocarcinoma cell line, Hep-2 and to investigate the possible mechanism of immune escape through Fas/FasL pathway in Hep-2 cell. METHOD: The mRNA and protein expressions of Fas and FasL in Hep-2 cell were analyzed by RT-PCR and flow cytometry (FCM). Growth curve of Jurkat cell was drawer based on the results of MMT, and apoptosis of Jurkat cell were determined by FCM and Hoechst 33342 staining after coculturing with Hep-2 cell. RESULT: The expressions of Fas and FasL in Hep-2 cell line were evaluated by flow cytometry and the mean fluorescence intensity were (32.91 +/- 5.6) and (25.57 +/- 7.1) respectively. After coincubation with Hep-2 cell (1 X 10(9)/L), the apoptosis rates of Jurkat cells were (38.95 +/- 0.11) % and (13.28 +/- 0.14) %, with planting concentration at 1 x 10(8)/L and 5 x 10 (8)/L respectively. In contrast, the apoptosis rate of Jurkat cultured separately was (7.53 +/- 0.17)%. The proliferation of Jurkat cell was obviously inhibited after coculture. However, the apoptosis rate was significantly decreased after adding neutralizing antibody of FasL. CONCLUSION Laryngocarcinoma cell could induce apoptosis of T lymphocytes through Fas-FasL system, thus it provided a potential mechanism to escape from immune surveillance of host.
Apoptosis ; Cell Line ; immunology ; Cell Line, Tumor ; Fas Ligand Protein ; metabolism ; Flow Cytometry ; Humans ; T-Lymphocytes ; immunology ; Tumor Escape ; fas Receptor ; metabolism

Aged ; Aged, 80 and over ; Biomarkers ; blood ; Chronic Disease ; Fas Ligand Protein ; Female ; Heart Failure ; blood ; etiology ; Humans ; Male ; Membrane Glycoproteins ; blood ; Middle Aged ; fas Receptor ; blood

This paper is to investigate the apoptosis effect of ovarian cancer SKOV3 cells induced by nanosecond plused electric fileds (nsPEFs) and to study its influence on Fas-mediated apoptosis. SKOV3 cell were exposed to the 45kV/cm of field intensity, 30 pulses, and 50ns, 100ns, and 200ns of pulse width, respectively. Flow cytometry were used to assay apoptosis. Agarose gel electrophoresis was used to detect DNA ladder. Real time PCR (RT-PCR) and Western blot analysis were used to measure the expression level of Fas, FasL, caspase-8 and Bid. Flow cytometry results revealed that the late apoptosis rates and (or) necrosis were significantly higher than those in control group (3.03% +/- 0.57%) (P < 0.05), with apoptosis rates and (or) necrosis being (18.31 +/- 0.65%), (45.55% +/- 3.71%), (47.47% +/- 7.01%) in the groups of 50ns, 100ns, 200ns, respectively. A typical DNA ladder pattern of internucleosomal fragmentation was observed in the groups of 50ns and 100ns, but not clear in the 200ns group. RT-PCR results revealed that the mRNA expression of Fas, FasL, caspase8 and Bid were significantly increased in groups of 50ns, 100ns, but significantly decreased in group of 200ns (P < 0.05). Meanwhile, Western blot analysis demonstrated that the Fas, FasL, Caspase-8 and Bid expression were significantly higher in groups of 50ns, 100ns, but significantly lower in group of 200ns (P < 0.05). It indicated that 45kV/cm, 50ns, 100ns nsPEFs could induce apoptosis in ovarian cancer SKOV3 cells and activate Fas-mediated apoptosis pathway.
Apoptosis ; radiation effects ; Caspase 8 ; metabolism ; Cell Line, Tumor ; Electromagnetic Fields ; Electroporation ; methods ; Fas Ligand Protein ; Female ; Humans ; Ovarian Neoplasms ; pathology ; fas Receptor ; metabolism

The aim of this study was to investigate the effects of the traditional Chinese medicine psoralen (PSO) plus long wave ultraviolet A (PUVA) on apoptosis in HL-60 leukemia cells and its mechanism. The effect of PUVA on HL-60 cell growth was assayed by MTT method and the changes of ultrastructure of cells were observed by electron microscopy. The apoptosis ratios, changes of mitochondrial membrane potential, expression of Fas and FasL protein and Fas and FasL mRNA were detected by FCM and fluorescent quantitation RT-PCR respectively. The expression of Caspase 8 and Caspase 3 protein were detected by immunocytochemistry (ICC). The results showed that the growth of HL-60 cells were inhibited by PUVA in time-and concentration-dependent manner through inducing cell apoptosis. When the irradiation time of long wave ultraviolet A lasted 15 minutes and the concentration of PSO was 80 microg/ml, the inhibition of HL-60 cell proliferation and apoptosis ratios reached the peak. There were obvious apoptotic ultrastructure changes and decrease of mitochondrial membrane potential in HL-60 cells after treatment with PUVA. The expression of Fas mRAN increased and expression of FasL mRNA decreased after treating with PUVA for 4 hours, and the same results of Fas, FasL expression on protein level were obtained also after treating with PUVA for 24 hours. The expression of caspase 8 and caspase 3 protein enhanced and reached the peak after treating with PUVA for 8 hours. It is concluded that the PUVA can inhibit the growth of HL-60 cells and induce apoptosis of these cells. The possible mechanism is supposed to be up-regulating Fas, down-regulating FasL levels and then activating the levels of caspase 8 and caspase 3. The decreasing of mitochondrial membrane potential may be involved in this process probably.
Apoptosis ; drug effects ; radiation effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Fas Ligand Protein ; metabolism ; Ficusin ; pharmacology ; HL-60 Cells ; Humans ; Ultraviolet Rays ; fas Receptor ; metabolism

The purpose of this study was to investigate the expression of Fas, Fas ligand (FasL) and CD80 and function of FasL on the surface of acute myelomonocytic leukemia cells from WEHI-3 line. The expression of Fas, FasL and CD80 on the surface of WEHI-3 were detected by flow cytometry, the apoptosis of YAC-1 cell induced by FasL on the surface of WEHI-3 were detected by (3)H-TdR incorporation. The results showed that the expression rate of Fas, FasL and CD80 on the surface of WEHI-3 cells were (6.75 +/- 2.31)% (n = 5), (63.73 +/- 5.23)% (n = 5) and (5.06 +/- 0.41)% (n = 5) respectively. The apoptosis rate of YAC-1 cells (target cells) co-cultured with WEHI-3 cells (Effector cells) at the rate of 1:3, 1:10 and 1:30 were (26 +/- 4.5)%, (35 +/- 3.2)% and (43 +/- 2.7)% (n = 5) respectively. It is concluded that WEHI-3 cells have high expression of FasL and low expression of Fas and CD80 on their cell membrane, and can induce the apoptosis of Fas(+) YAC-1 cells.
Apoptosis ; physiology ; B7-1 Antigen ; biosynthesis ; Cell Membrane ; metabolism ; Fas Ligand Protein ; biosynthesis ; Humans ; Leukemia, Myelomonocytic, Acute ; metabolism ; pathology ; Tumor Cells, Cultured ; fas Receptor ; biosynthesis

OBJECTIVETo observe the serum and placental levels of FAS and FASL in preeclampsia (PE) and to study its relationship with the disease.

METHODSForty women with preeclampsia and 39 healthy pregnant women were recruited and samples of serum and placentas were collected. The expression of Fas and FasL in placentas was detected with Western blot and the concentration of soluble Fas and FasL in serum was detected with ELISA method.

RESULTSerum levels of soluble Fas in PE group were significantly higher than those of healthy pregnant women (2.11+/-0.95 mg/L compared with 1.57+/-0.60 mg/L, P<0.05), and serum levels of soluble FasL in PE group were also significantly higher than those in controls (4.43+/-1.90 g/L compared with 3.48+/-1.53 g/L, P<0.01). There were no significant differences in Fas and FasL levels in placentas between PE group and healthy pregnant women (P>0.05 for both).

CONCLUSIONThe elevated serum Fas and FasL levels are closely associated with preeclampsia, which may play an important role in the pathogenesis of the disease.

Adult ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Fas Ligand Protein ; blood ; Female ; Humans ; Placenta ; metabolism ; Pre-Eclampsia ; blood ; metabolism ; Pregnancy ; fas Receptor ; blood

OBJECTIVETo investigate the mechanism of immune escape in renal cell carcinoma(RCC).

METHODSFas and FasL expressions were examined by immunohistochemical technique in 44 RCC patients, with the Ki67 expression and apoptosis of tumor infiltrating lymphocytes(TIL) monitored simultaneously. Cytokines including IL2 and IFN alpha were used to induce the expression of the renal carcinoma cell lines 786-0 cells. Combination treatment of 786-0 with cytokines and Anti-Fas monoclonal antibody (FasAb) was used to induce apoptosis. FasL function was assessed by in vitro co-culture assays using renal cancer cells 786-0 and Fas-sensitive Jurkat T-cells.

RESULTS(1) Fas expression rate in RCC(22.8%) was lower than that in the controlled normal kidney tissues(53.8%, P < 0.01). FasL expression rate in RCC (46.5%) was higher than that in the controlled normal kidney tissues (23.2%, P < 0.01). That of Ki67 was 32.8%, with the expressions of Fas and Ki67 showing a negative correlation (r = -0.62, P < 0.05). In contrast, the expressions of FasL and Ki67 showed a positive correlation. (r = 0.93, P < 0.01). The Fas expression of stage I was significantly higher than that of stages III and IV. The expression rate of FasL in RCC was significantly increased with RCC stage (P < 0.01). (2) The apoptotic rate of TIL in RCC (33.9%) was significantly higher than that of the normal kidney tissues (3.5%, P < 0.01). The expression of FasL and the apoptotic rate of TIL in RCC gave a positive correlation (r = 0.96, P < 0.01). (3) Fas expression rate in 786-0 cells was 13.7%. The apoptotic rate mediated by FAsAb was 9.6%. IFN alpha was able to up-regulate the Fas expression and subsequently augment the FasAb-mediated apoptosis in 786-0 cells. But IL2 did not show similar effects. (4) The FasL expression rate of 786-0 was 18.6%. FasL expressed by 786-0 cells was able to induce apoptosis of Jurkat T-cells in co-culture assays and the apoptosis of Jurkat T-cells was significantly lowered after blocking the effect of FasL with Fas-neutralizing antibody NOK-2, giving the apoptotic rates of 14.9% and 2.0%, respectively, the difference therein is statistically significant (P < 0.01).

CONCLUSIONDown-regulation of Fas expression and up-regulation of FasL-expression are the mechanisms through which the RCC cells escape from immune attack.

Adult ; Aged ; Carcinoma, Renal Cell ; immunology ; Fas Ligand Protein ; Female ; Humans ; Ki-67 Antigen ; immunology ; Kidney Neoplasms ; immunology ; Male ; Membrane Glycoproteins ; immunology ; Middle Aged ; fas Receptor ; immunology