Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transgenic CD1 mice expressing beta-galactosidase were used as myoblast donors. The myoblasts were injected in normal or mdx muscles previously irradiated and injected with notexin. Twenty-eight days after myoblast transplantation, the percentage of muscle fibers beta-glactosidase-positive was low in mice not immunosuppressed but was high (80%) in those treated with FK506. In mdx mice, muscle fibers expressing beta-galactosidase were also dystrophin positive. Most of the mice not treated with FK506 produced antibodies against the donor myoblasts. These results indicate that FK506 is a very useful immunosuppressive drug for myoblast transplantation in mice. Irradiation and notexin injection used in our experiments are, however, not feasible in humans. Other manipulations capable of increasing the participation of donor myoblasts to regeneration will therefore have to be identified before new clinical trials are attempted.
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PMID:Very efficient myoblast allotransplantation in mice under FK506 immunosuppression. 752 8

The effect of pretreatment of cultures with basic fibroblast growth factor (bFGF) on myoblast allotransplantation to C57BL/10ScSn mdx/mdx mouse (mdx mouse) muscles not previously damaged and not irradiated was studied. Transgenic CD1 mice which have a beta-galactosidase gene under the control of the promoter of the quail fast skeletal muscle troponin I gene, were used as donors. The myoblasts were grown with 100 ng/mL bFGF during the last 2 days before injecting them in the left tibialis anterior (TA) muscles of mdx mice. Myoblasts from the same primary cultures were also grown without bFGF and injected in the right TA muscles as control. The recipient mice were immunosuppressed with FK 506. Twenty-eight days after myoblast transplantation, the percentage of beta-galactosidase-positive fibers was significantly higher (more than fourfold) following culture with bFGF than without bFGF. Almost all beta-galactosidase-positive fibers were also dystrophin positive. Direct intramuscular injections of bFGF or of Hank's balanced salt solution (HBSS) at the time of myoblast transplantation and at several intervals afterwards were also investigated. The percentage of beta-galactosidase-positive fibers did not differ significantly following intramuscular injection of bFGF from controls injected with HBSS. In vitro, this high concentration of bFGF significantly reduced the formation of myotubes, and the percentage of mononuclear cells which were myoblasts was significantly increased by 34%. These observations alone do not account for the fourfold increase in transplantation success. The presence of bFGF in the culture did not significantly increase the cell survival 3 days after their transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pretreatment of myoblast cultures with basic fibroblast growth factor increases the efficacy of their transplantation in mdx mice. 763 Mar 43

CD28 is a 44 kDa Ig superfamily cell surface molecule expressed on most mature T cells. Through its interaction with the recently identified B7/BB1 counter-receptor, it is believed to play an important role as a co-stimulator of T cells along with the TCR-CD3 complex. Activation of T cells with CD28 mAbs synergizes with TCR-CD3 and CD2 stimulation, resulting in long term T cell proliferation, differentiation of cytotoxic T cells and production of large amounts of cytokines. In order to further delineate the role of CD28 in signal transduction and T cell activation, human CD28 was transfected into CD3+ murine T cell hybridomas. High levels of cell surface CD28 expression was achieved by protoplast fusion. The transfected molecule retained all the native CD28 mAb epitopes found on human T cells. In these transfectants, CD28 mAbs, similarly to CD3 mAbs, were able to induce Ca2+ mobilization, IL-2 promoter induction (measured as beta-galactosidase activity in T cells hybridomas pre-transfected with the IL-2-lac Z reporter gene), IL-2 secretion, TNF alpha production and apoptosis (observed as growth arrest and genome fragmentation). The parental host cells, or cells transfected with vector alone, responded only to mAbs to CD3. IL-2 secretion in the transfectants was obtained using either an IgM mAb to CD28 or IgG mAbs presented on the surface of IgG-FcR+ B lymphoma cells. Optimal activation via CD28 was inhibited by suboptimal concentrations of soluble CD3 mAb, suggesting an interaction between the two pathways. The immunosuppressive drugs Cyclosporin A and FK506 completely blocked CD28 and CD3 mediated IL-2 production in these transfectants whereas rapamycin had only a partial inhibitory effect. Finally, since the transfected human CD28 molecule confers full functional responsiveness to the murine T cell hybridomas without the need for costimulators such as PMA, this model is ideal for studying the structure-function relationships of the CD28 molecule as well as the transmembrane and cytoplasmic associations implied in CD28 signaling.
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PMID:Functional expression of human CD28 in murine T cell hybridomas. 830 98

Despite good initial success in vivo, gene transfer using first-generation replication-defective adenovirus has been reported to lead to transient reporter gene expression and to trigger inflammatory reactions in various organs and animal models. To gain more knowledge on this phenomenon, immune reactions were investigated following in vivo transfection of adult immunocompetent mouse muscle using a delta E1/E3a adenoviral vector encoding a beta-galactosidase (beta-Gal) expression cassette. Cellular and humoral immune reactions, and rejection of beta-Gal-positive muscle fibers, occurred within 3 weeks. The muscles showed massive infiltration by macrophages, natural killer cells, and CD8+ leukocytes. The mRNA levels of granzyme B and interferon-gamma were increased 6 days after vector injection, indicating that the infiltrating lymphocytes were activated. Antibodies were formed against the adenovirus group antigen and the beta-Gal gene product 2 weeks after construct injection. The immunosuppressant FK506, however, blocked the cellular infiltration and the humoral response and allowed strong, stable transgene expression over 1 month. These data emphasize the immune problems related to the use of delta E1/E3a adenoviruses as vectors for gene therapy, and they underline the potential of FK506 as an immunosuppressant adjunct treatment for adenovirus-mediated gene transfer.
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PMID:FK506 immunosuppression to control the immune reactions triggered by first-generation adenovirus-mediated gene transfer. 857 12

Laminin-2 is a component of skeletal and cardiac basal lamina expressed in normal mouse and human. Laminin alpha2 chain (LAMA2), however, is absent from muscles of some congenital muscular dystrophy patients and the dystrophia muscularis (dy/dy) mouse model. LAMA2 restoration was investigated following cell transplantation in vivo in dy/dy mouse. Allogeneic primary muscle cell cultures expressing the beta-galactosidase transgene under control of a muscular promoter, or histocompatible primary muscle cell cultures, were transplanted into dy/dy mouse muscles. FK506 immunosuppression was used in noncompatible models. All transplanted animals expressed LAMA2 in these immunologically-controlled models, and the degrees of LAMA2 restoration were shown to depend on the age of the animal at transplantation, on muscle pretreatment, and on duration time after transplantation in some cases. LAMA2 did not always colocalize with new or hybrid muscle fibers formed by the fusion of donor myoblasts. LAMA2 deposition around muscle fibers was often segmental and seemed to radiate from the center to the periphery of the injection site. Allogeneic conditionally immortalized pure myogenic cells expressing the beta-galactosidase transgene were characterized in vitro and in vivo. When injected into FK506-immunosuppressed dy/dy mice, these cells formed new or hybrid muscle fibers but essentially did not express LAMA2 in vivo. These data show that partial LAMA2 restoration is achieved in LAMA2-deficient dy/dy mouse by primary muscle cell culture transplantation. However, not all myoblasts, or myoblasts alone, or the muscle fibers they form are capable of LAMA2 secretion and deposition in vivo.
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PMID:Partial laminin alpha2 chain restoration in alpha2 chain-deficient dy/dy mouse by primary muscle cell culture transplantation. 860 7

Myoblasts were grown from monkey muscle biopsies and infected in vitro with a defective retroviral vector containing a cytoplasmic beta-galactosidase (beta-gal) gene. These myoblasts were then transplanted to 14 different monkeys, 6 of which were immunosuppressed with FK506. Without immunosuppression, only a few myoblasts and myotubes expressing beta-gal were observed 1 week after the transplantation, but no cells expressing beta-gal were observed after 4 weeks. This result was attributed to immune responses since infiltration by CD4+ or CD8+ lymphocytes was abundant 1 week after transplantation but not after 4 weeks. The expression of interleukin 6 (IL-6), interleukin 2 (IL-2), granulocyte/macrophage colony stimulating factor (GM-CSF), transforming growth factor-beta (TGF-beta) and granzyme B mRNAs was increased in the myoblast-injected muscle indicating that the infiltrating lymphocytes were activated. Moreover, antibodies against the donor myoblasts were detected in 3 out of 6 cases. When the monkeys were immunosuppressed with FK506, muscle fibers expressing beta-galactosidase (beta-gal) were present 1, 4 and 12 weeks after the transplantation. There was neither significant infiltration by CD4 or CD8 lymphocytes, nor antibodies detected. The mRNA expression of most cytokines was significantly reduced as compared to the nonimmunosuppressed monkeys. These results indicate that FK506 is effective in controlling short-term immune reactions following myoblast transplantation in monkeys and suggest that it may prove useful for myoblast transplantation in Duchenne Muscular Dystrophy patients.
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PMID:Myoblast transplantation in monkeys: control of immune response by FK506. 864 94

The therapeutic potential of adenovirus-mediated gene transfer using first-generation vectors is severely limited by the fact that only transient expression is achievable in immunocompetent animals. The loss in transgene expression can be attributed at least in part to the appearance of detrimental immune responses directed toward vector and/or transgene-encoded determinants. FK506 and cyclosporin A both reduced these immune responses. These immunosuppressants, however, may induce many severe side effects during prolonged use. An alternative strategy has been developed to overcome these problems following in vivo transfection of muscles of adult immunocompetent mice with a delta E1/E3a adenoviral vector encoding a beta-galactosidase (beta-Gal) expression cassette. YTS 177 (an anti-CD4 monoclonal antibody) as well as CTLA4Ig, a recombinant protein, partially controlled the immune responses. They were indeed able to reduce the muscle infiltration by CD4+ and CD8+ cells but they failed to repress the humoral response. Co-administration of YTS 191 (an anti-CD4), YTS 169 (an anti-CD8), and TIB 213 (an anti-CD11a) was, however, very efficient in blocking both cellular and humoral immune reactions. This combination of monoclonal antibodies allowed strong and stable transgene expression over 1 month. These data underline the potential of monoclonal antibodies as immunosuppressive adjunct treatment for adenovirus-mediated gene transfer.
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PMID:Prevention of immune reactions triggered by first-generation adenoviral vectors by monoclonal antibodies and CTLA4Ig. 884 5

First generation, replication-defective adenoviral vectors are highly effective for gene transfer into the central nervous system, but the host's immune response limits the utility of this vector for possible therapy of neurological disease or long-term gene transfer studies in experimental animals. We have demonstrated the effectiveness of FK506 (tacrolimus), a powerful immunosuppressant that readily crosses the blood-brain barrier, in maintaining adenovirus-mediated reporter gene transfer following stereotaxic injection of the recombinant (AdCMVlacZ) into mouse striatum. After 28 days, beta-galactosidase expression was reduced by 75% relative to day 10 in immunocompetent animals, accompanied by an inflammatory reaction in the region of transduced cells; however, in mice receiving daily s.c. injections of FK506, beta-galactosidase activity was maintained at the 10 days post-injection level.
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PMID:The immunosuppressant FK506 prolongs transgene expression in brain following adenovirus-mediated gene transfer. 924 94

Myoblast transplantation is a potential treatment for Duchenne muscular dystrophy. One of the problems possibly responsible for the limited success of clinical trials is the rapid death of the myoblasts after transplantation. To investigate this problem, myoblasts expressing beta-galactosidase were injected in the tibialis anterior muscles of mice. Beta-galactosidase activity was reduced by 74.7% after 3 days. Myoblast death observed at 3 days was reduced to 57.2% when the hosts were irradiated. This result suggested that host cells were contributing to this phenomenon. Transplantation in SCID and FK506-treated mice did not reduce cell death, indicating that mortality was not due to an acute specific reaction. In contrast, administration of the anti-LFA-1 (TIB-213) mAb markedly reduced myoblast death at 3 days without altering leukocyte tissue infiltration. We postulated that neutrophils were mediating myoblast mortality by an LFA-1-dependent mechanism. To test this hypothesis, IL-1beta-activated myoblasts were loaded with 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate, di(acetoxymethylester) (DCFH), a marker for oxidative stress. Addition of neutrophils and zymosan-activated serum resulted in a time-dependent DCFH fluorescence; this neutrophil-induced oxidation was considerably inhibited by TIB-213. These results indicate that an effective control of the inflammatory reaction will be necessary for any new clinical trials of myoblast transplantation and suggest that neutrophil-mediated myoblast injury occurs by an LFA-1-dependent pathway.
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PMID:Prevention by anti-LFA-1 of acute myoblast death following transplantation. 927 46

The host immune response limits the duration of expression of adenovirally transduced genes and precludes long-term gene expression upon re-administration of the virus. In this study we wished to evaluate whether short-term immunosuppression of the host, at the time of recombinant virus administration, would allow expression of the therapeutic gene product upon virus reinjection. Gunn rats were used as recipients of recombinant adenoviruses expressing human BUGT (Ad-hBUGT) or E. coli beta-galactosidase (Ad-LacZ). Rats were treated with FK506 (1-1.5 mg/kg, per OS daily) for three days beginning 24 hours before each virus injection. Control groups did not receive any immunosuppressant. The serum bilirubin level was reduced from 7.1 +/- 0.75 mg/dL to 2.0 +/- 0.7 mg/dL within two days of viral injection in both FK506 treated and control groups, and then gradually increased in 6 weeks. FK506-treated rats had low or undetectable antibody titers against the recombinant adenovirus and minimal or no cytotoxic T lymphocyte (CTL) response against adenovirus-infected cells. The tolerized rats received two subsequent injections 42 and 98 days after the first injection, which reduced the bilirubin levels again to 2.0 +/- 0.56 and 2.2 +/- 0.61 mg/dL, respectively. In contrast, control rats developed high titer neutralizing antibodies and a CTL response, and their serum bilirubin levels were not reduced following subsequent injections. We conclude that short-term FK506 treatment around the time of virus administration prevents the host immune response, permitting long-term gene therapy by repeated administration of the recombinant virus.
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PMID:Transient immunosuppression with FK506 permits long-term expression of therapeutic genes introduced into the liver using recombinant adenoviruses in the rat. 932 18


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