To investigate the value of apoptosis of the allo-antigen specific T cells induced by Fas/FasL pathway in preventing graft-versus-host disease (GVHD), the CD34+ cells transfected with FasL or not, used as stimulus cells, were mixed with allo-antigen specific T lymphocytes in presence or absence of IFN-gamma and IL-2. After 5 days, apoptosis of T cells was detected by TdT nick end mediated dUTP labeling (TUNEL) and flow cytometry (FCM). The affects of these two cytokines on CD34+ cells in the graft were also compared. The ratio of apoptosis of T cells was 12.1+/-1.5% when CD34+ cells transfected with FasL was used as stimulus cells, much higher than that of CD34+ cells non-transfected (3.2+/-1.1%, P<0.01). And in presence of IFN-gamma or IL-2, the ratio reached 20.1+/-2.3%, 17.6+/-1.3% respectively (P<0.01). However, IFN-gamma up-regulated Fas expression of CD34+ cells and increased the sensibility of CD34+ cells to soluble FasL (sFasL); IL-2 showed no such effect. It is possible to induce apoptosis of the allo-antigen specific T cells of grafts activated by allo-antigen by exogenous Fas ligand expressed on recipient cells and this might provide a new approach for preventing GVHD and IL-2 may be more suitable for clinical application.
Antigens, CD34 ; biosynthesis ; immunology ; Apoptosis ; Cytotoxicity, Immunologic ; DNA, Complementary ; genetics ; Fas Ligand Protein ; Graft vs Host Disease ; prevention & control ; Interferon-gamma ; biosynthesis ; immunology ; Interleukin-2 ; biosynthesis ; immunology ; Membrane Glycoproteins ; biosynthesis ; immunology ; T-Lymphocytes ; cytology ; physiology ; fas Receptor ; biosynthesis ; immunology

OBJECTIVETo investigate the clinical characteristics of a Chinese pedigree with cardiac conductive disease complicated by atrial fibrillation and the therapeutic effect of the treatments.

METHODSAll the family members including the proband were screened with routine examination, electrocardiography, echocardiograpy, Holter recording, chest X-ray, blood biochemistry tests and autoantibody test. The proband received dual chamber pacemaker implantation combined with oral amiodarone treatment for 3 months. The patient was monitored for thyreoid function and chest X-ray during the treatments, and was followed up for another 3 months.

RESULTSClinical evidence of organic heart disease was found in none of the family members. The proband showed recurrent dizziness and chest distress, which exacerbated after exercise, and ECG showed atrial fibrillation and severe A-V block. The proband's uncle was found to have atrial fibrillation and III degree A-V block after a syncope episode at the age of 30, and received a pacemaker treatment. Her grandpa died from a heart attack without detailed clinical documentations. No other family members showed abnormal ECG or a history of any heart events. The proband's condition was improved by treatments, after which ECG and Holter recording showed pace rhythm without atrial fibrillation.

CONCLUSIONCardiac conductive disease with atrial fibrillation can present in one family, and can be managed effectively and safely with implantation of dual chamber pacemaker combined with oral amiodarone.

Asian Continental Ancestry Group ; Atrial Fibrillation ; complications ; genetics ; therapy ; Atrioventricular Block ; complications ; genetics ; therapy ; Cardiac Resynchronization Therapy ; Female ; Heart Conduction System ; abnormalities ; Humans ; Pedigree ; Young Adult

To assess the value of CD34+ cells transferred exogenous Fas ligand (FasL) in inducing apoptosis of human leukemic cells, the CD34+ cells transfected with FasL or without, pretreated with mitomycin C, was mixed with leukemic cell line U937 cells in presence or absence of daunorubicin (DNR) or cytosine arabinoside (Ara-C). After 18 h, apoptosis of cells was detected by FCM and TUNEL. Induced for 18 h by CD34+ cells transfected with FasL or without, the ratio of apoptosis of U937 cells was (5.0 +/- 1.3)%, (10.8 +/- 0.6)% (P < 0.01), respectively. Induced by FasL+ CD34+ + DNR, FasL+ CD34+ + Ara-C, the ratio was (13.4 +/- 1.0)% (P < 0.05), (17.9 +/- 1.3)% (P < 0.01), respectively. The result demonstrated that CD34+ cells transfected with exogenous FasL could induce apoptosis of human leukemic cells and showed a cytotoxic synergistic effect when used in combination with chemotherapeutic drugs, suggesting that it was possible to develop a new method in treatment of leukemia.
Antigens, CD34 ; analysis ; Apoptosis ; drug effects ; Cell Communication ; physiology ; Cytarabine ; pharmacology ; DNA, Complementary ; genetics ; Daunorubicin ; pharmacology ; Fas Ligand Protein ; Humans ; Membrane Glycoproteins ; genetics ; Mitomycin ; pharmacology ; Transfection ; U937 Cells ; fas Receptor ; genetics ; metabolism

In order to regulate the apoptosis induced by Fas-FasL system, a soluble isoform of mouse Fas was cloned from thymocytes of immature mice with the primers designed according to the full-length Fas cDNA sequence in the GeneBank. It was directionally inserted into the intermedium vector pUC19. DNA sequencing proved that it was consistent with the expected sequence. Then it was subcloned into the eukaryotic expression vector pCA13, which was used to construct the recombinant vector pCA13-FasC. By lipofectamine (LF2000)-mediated transfection, pCA13-FasC was transfected into the 293 cells. RT-PCR and Western blot indicated that the murine soluble Fas C protein was expressed in the 293 cells. Apoptosis inducing test showed that the expression of this murine Fas C could block the Fas-induced apoptosis, which confirmed the biological activity of the recombinant Fas C.
Amino Acid Sequence ; Animals ; Animals, Newborn ; Base Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Fas Ligand Protein ; Gene Expression ; Membrane Glycoproteins ; biosynthesis ; genetics ; Mice ; Molecular Sequence Data ; Recombinant Proteins ; biosynthesis ; Sequence Analysis, DNA ; Sequence Homology, Amino Acid ; Transfection ; fas Receptor ; biosynthesis ; genetics

In order to explore a new special and effective way to prevent graft versus host disease (GVHD) after allogenic bone marrow transplantation (allo-BMT), the stem cell antigen-1 (Sca-1) + early hematopoietic cells (EHC) from BALB/c mouse (H-2d) were introduced with exogenous mouse Fas ligand (mFasL) cDNA gene by the retrovirus-mediated gene transfer and expanded for one week, and then they were co-cultured with the spleen mononuclear cells (SMNC) from BAC mouse (H-2dxb) as one way mixed lymphocyte reaction (OWMLR). The cytotoxicity of treated BAC mouse SMNC against Na2 51CrO4 labeling SMNC from BALB/c mouse was observed. The bone marrow mononuclear cells (BMMNC) from BAC mouse treated by the above methods were transplanted into lethally-irradiated congenic BALB/c mice to observe the occurrence of GVHD. The results showed that the SMNC from BAC mouse after OWMLR with exogenous mFasL cDNA gene-transduced hematopoietic cells (HC) from BALB/c mouse in a ratio of 1 to 5 exhibited an obvious inhibition of the cytotoxicity against the BALB/c mouse spleen cells at different effector/target ratios as compared to the control group (P<0.01). The grade I GVHD or no GVHD and the 80% survival rate at day 60 post-BMT were observed in the BALB/c mouse receiving BAC mouse BMMNC treated with similar way, while the grade II - III GVHD and the 20% survival rate were noted in the control group (P<0.01). It is suggested that the attenuation of GVHD in allo-BMT recipient could be successfully achieved through FasL-Fas pathway in an H-2 haplotype disparate mouse combination.
Animals ; Bone Marrow Transplantation ; Fas Ligand Protein ; Female ; Graft vs Host Disease ; immunology ; therapy ; H-2 Antigens ; genetics ; Haplotypes ; Hematopoietic Stem Cells ; cytology ; immunology ; Membrane Glycoproteins ; immunology ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Rats ; Rats, Wistar ; Signal Transduction ; Spleen ; cytology ; immunology ; T-Lymphocytes ; immunology ; Transfection ; fas Receptor ; immunology