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Sample records for cell specific cytotoxicity

  1. Concanavalin A-induced activation of lymphocytic choriomeningitis virus memory lymphocytes into specifically cytotoxic T cells

    DEFF Research Database (Denmark)

    Marker, O; Thomsen, Allan Randrup; Andersen, G T

    1977-01-01

    When spleen cells, which have been primed to Lymphocytic Choriomeningitis (LCM) virus during a primary infection several months previously, are stimulated in vitro with Con A. highly specific secondary cytotoxic effector cells are generated. The degree of cytotoxicity revealed by such Con A...

  2. Mechanism of arctigenin-mediated specific cytotoxicity against human lung adenocarcinoma cell lines.

    Science.gov (United States)

    Susanti, Siti; Iwasaki, Hironori; Inafuku, Masashi; Taira, Naoyuki; Oku, Hirosuke

    2013-12-15

    The lignan arctigenin (ARG) from the herb Arctium lappa L. possesses anti-cancer activity, however the mechanism of action of ARG has been found to vary among tissues and types of cancer cells. The current study aims to gain insight into the ARG mediated mechanism of action involved in inhibiting proliferation and inducing apoptosis in lung adenocarcinoma cells. This study also delineates the cancer cell specificity of ARG by comparison with its effects on various normal cell lines. ARG selectively arrested the proliferation of cancer cells at the G0/G1 phase through the down-regulation of NPAT protein expression. This down-regulation occurred via the suppression of either cyclin E/CDK2 or cyclin H/CDK7, while apoptosis was induced through the modulation of the Akt-1-related signaling pathway. Furthermore, a GSH synthase inhibitor specifically enhanced the cytotoxicity of ARG against cancer cells, suggesting that the intracellular GSH content was another factor influencing the susceptibility of cancer cells to ARG. These findings suggest that specific cytotoxicity of ARG against lung cancer cells was explained by its selective modulation of the expression of NPAT, which is involved in histone biosynthesis. The cytotoxicity of ARG appeared to be dependent on the intracellular GSH level. PMID:24021157

  3. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs.

    Science.gov (United States)

    Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko; Bradford, Andrew P; Komori, Hideyuki; Ohtani, Kiyoshi

    2014-07-18

    In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter is activated by E2F only in cancer cells and therefore may be more cancer cell-specific than E2F1 promoter to drive gene expression. We show here that the ARF promoter has lower activity in normal growing fibroblasts and shows higher cancer cell-specificity compared to the E2F1 promoter. We also demonstrate that adenovirus expressing HSV

  4. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

    International Nuclear Information System (INIS)

    Highlights: • ARF promoter showed higher responsiveness to deregulated E2F activity than the E2F1 promoter. • ARF promoter showed higher cancer cell-specificity than E2F1 promoter to drive gene expression. • HSV-TK driven by ARF promoter showed higher cancer cell-specific cytotoxicity than that driven by E2F1 promoter. - Abstract: In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter

  5. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

    Energy Technology Data Exchange (ETDEWEB)

    Kurayoshi, Kenta [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Ozono, Eiko [Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary, University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ (United Kingdom); Iwanaga, Ritsuko; Bradford, Andrew P. [Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045 (United States); Komori, Hideyuki [Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 (United States); Ohtani, Kiyoshi, E-mail: btm88939@kwansei.ac.jp [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2014-07-18

    Highlights: • ARF promoter showed higher responsiveness to deregulated E2F activity than the E2F1 promoter. • ARF promoter showed higher cancer cell-specificity than E2F1 promoter to drive gene expression. • HSV-TK driven by ARF promoter showed higher cancer cell-specific cytotoxicity than that driven by E2F1 promoter. - Abstract: In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter

  6. Ulcerative colitis specific cytotoxic IgG-autoantibodies against colonic epithelial cancer cells.

    OpenAIRE

    Auer, I O; Grosch, L; Hardörfer, C; A. Röder

    1988-01-01

    Serum antibodies cytotoxic to the colon cancer cell line RPMI 4788 were studied in 42 patients with ulcerative colitis, 61 patients with Crohn's disease, 27 patients with other inflammatory diseases (disease-controls) and 22 healthy controls. Cytotoxicity of antibodies towards RPMI 4788 was studied by means of a chromium release assay using peripheral blood mononuclear leucocytes of healthy subjects as effector cells. Using a four hour antibody dependent cell mediated cytotoxicity assay sera ...

  7. Ionizing radiation affects generation of MART-1-specific cytotoxic T cell responses by dendritic cells

    International Nuclear Information System (INIS)

    Full text: The human MART-1/Melan-A (MART-1) melanoma tumor antigen is known to be recognized by cytotoxic T lymphocytes (CTLs) and several groups are using this target for clinical immunotherapy. Most approaches use dendritic cells (DCs) that are potent antigen presentation cells for initiating CTL responses. In order for CTL recognition to occur, DCs must display 9-residue antigenic peptides on MHC class I molecules. These peptides are generated by proteasome degradation and then transported through the endoplasmic reticulum to the cell surface where they stabilize MHC class I expression. Our previous data showed that irradiation inhibits proteasome function and, therefore, we hypothesized that irradiation may inhibit antigen processing and CTL activation, as has been shown for proteasome inhibitors. To study the importance of irradiation effects on DCs, we studied the generation MART-1-specific CTL responses. Preliminary data showed that irradiation of murine bone marrow derived DCs did not affect expression of MHC class I, II, CD80, or CD86, as assessed by flow cytometric analyses 24-hour after irradiation. The effect of irradiation on MART-1 antigen processing by DCs was evaluated using DC transduced with adenovirus MART-1 (AdVMART1). C57BL/6 mice were immunized with AdVMART1 transduced DCs, with and without prior irradiation. IFN-γ production was measured by ELISPOT assays after 10-14 days of immunization. Prior radiation treatment resulted in a significant decrease in MART-1-specific T cell responses. The ability of irradiated and non-irradiated AdVMART1/DC vaccines to protect mice against growth of murine B16 tumors, which endogenously express murine MART-1, was also examined. AdVMART1/DC vaccination protected C57BL/6 mice against challenge with viable B16 melanoma cells while DCs irradiated (10 Gy) prior to AdVMART1 transduction abrogated protection. These results suggest that proteasome inhibition in DCs by irradiation may be a possible pathway in

  8. Potent Antitumor Activity Generated by a Novel Tumor Specific Cytotoxic T Cell.

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    Full Text Available Hepatocellular carcinoma is one of the most common malignant neoplasms in the world and is the main cause of death in patients with liver cirrhosis. Surgical intervention is not suitable for majority of hepatocellular carcinoma. Investigation of the effective targeting to the tumor cells is essential for both primary tumors and metastases. Tumor specific cytotoxic T lymphocytes (CTL have been considered to be the attractive vehicles for delivering therapeutic agents toward various tumor diseases. This study was to explore the distribution pattern of CTL carrying the lentiviral vectors with the characteristic of adenoviral E1 gene under the control of the cell activation-dependent CD40 ligand promoter (Lenti/hCD40L/E1AB. Following transduction with adenoviral vectors containing chimeric type 5 and type 35 fiber proteins (Ad5/35-TRAIL, these CTLs produced infectious virus when exposed to HepG2 cells. We assessed the therapeutic ability of CTLs using MTT, Western blot and colony formation assay. The novel CTL harboring Lenti/hCD40L/E1AB and Ad5/35-TRAIL caused proliferation inhibition and significant apoptosis in hepatocellular carcinoma cell lines. Thus, the novel CTL may be useful for the development of gene therapy approaches to hepatocellular carcinoma.

  9. Indoleamine 2,3-dioxygenase specific, cytotoxic T cells as immune regulators

    DEFF Research Database (Denmark)

    Sørensen, Rikke Bæk; Hadrup, Sine Reker; Svane, Inge Marie; Hjortso, Mads Christian; Straten, Per Thor; Andersen, Mads Hald

    2011-01-01

    Indoleamine 2,3-dioxygenase (IDO) is an immunoregulatory enzyme that is implicated in suppressing T-cell immunity in normal and pathologic settings. Here, we describe that spontaneous cytotoxic T-cell reactivity against IDO exists not only in patients with cancer but also in healthy persons. We...... caused an increase in the production of the proinflammatory cytokines IL-6 and tumor necrosis factor-alpha while decreasing the IL-10 production. Finally, the addition of IDO-inducing agents (ie, the TLR9 ligand cytosine-phosphate- guanosine, soluble cytotoxic T lymphocyte-associated antigen 4, or...

  10. Induction of cancer-specific cytotoxicity towards human prostate and skin cells using quercetin and ultrasound

    OpenAIRE

    Paliwal, S; SUNDARAM, J.; Mitragotri, S

    2005-01-01

    Bioflavonoids, such as quercetin, have recently emerged as a new class of chemotherapeutic drugs for the treatment of various cancer types, but are marred by their low potency and poor selectivity. We report that a short application of low-frequency ultrasound selectively sensitises prostate and skin cancer cells against quercetin. Pretreatment of cells with ultrasound (20 kHz, 2 W cm−2, 60 s) selectively induced cytotoxicity in skin and prostate cancer cells, while having minimal effect on c...

  11. Dendritic cells loaded with killed breast cancer cells induce differentiation of tumor-specific cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Early clinical trials, mostly in the setting of melanoma, have shown that dendritic cells (DCs) expressing tumor antigens induce some immune responses and some clinical responses. A major difficulty is the extension to other tumors, such as breast carcinoma, for which few defined tumor-associated antigens are available. We have demonstrated, using both prostate carcinoma and melanoma as model systems, that DCs loaded with killed allogeneic tumor cell lines can induce CD8+ T cells to differentiate into cytotoxic T lymphocytes (CTLs) specific for shared tumor antigens. The present study was designed to determine whether DCs would capture killed breast cancer cells and present their antigens to autologous CD4+ and CD8+ T cells. We show that killed breast cancer cells are captured by immature DCs that, after induced maturation, can efficiently present MHC class I and class II peptides to CD8+ and CD4+ T lymphocytes. The elicited CTLs are able to kill the target cells without a need for pretreatment with interferon gamma. CTLs can be obtained by culturing the DCs loaded with killed breast cancer cells with unseparated peripheral blood lymphocytes, indicating that the DCs can overcome any potential inhibitory effects of breast cancer cells. Loading DCs with killed breast cancer cells may be considered a novel approach to breast cancer immunotherapy and to identification of shared breast cancer antigens

  12. Recognition of breast cancer cells by CD8+ cytotoxic T-cell clones specific for NY-BR-1.

    Science.gov (United States)

    Wang, Wei; Epler, Jennifer; Salazar, Lupe G; Riddell, Stanley R

    2006-07-01

    Immunotherapy for breast cancer using cytotoxic T cells (CTL) is hindered by the lack of well-characterized breast cancer antigens that are expressed in most breast tumor cells and recognized by CD8+ CTL. A recently described breast tissue differentiation antigen, NY-BR-1, is expressed in >80% breast tumors and elicits a humoral response in a subset of breast cancer patients. To identify potential NY-BR-1 epitopes that are recognized by CTL, CD8+ T cells were stimulated in vitro with autologous dendritic cells pulsed with NY-BR-1 peptides that were predicted to bind to HLA-A2. In multiple normal female donors and breast cancer patients, specific CD8+ CTL responses were detected by enzyme-linked immunospot assay against several NY-BR-1 peptides after two cycles of stimulation. CD8+ CTL clones against three NY-BR-1 epitopes were isolated and recognized peptide-pulsed target cells with high avidity. T-cell clones specific for one of the NY-BR-1 epitopes (p904) also recognized breast tumor cells expressing NY-BR-1, NY-BR-1(-) cells transfected with a cDNA encoding the NY-BR-1 protein, and autologous dendritic cells pulsed with opsonized NY-BR-1+ breast tumor cells. Taken together, these results show that the p904 epitope derived from NY-BR-1 is efficiently processed and presented endogenously and identify NY-BR-1 as a promising target for T-cell-based immunotherapy for breast cancer. PMID:16818660

  13. Host cell cytotoxicity, cellular repopulation dynamics, and phase-specific cell survival in X-irradiated rat rhabdomyosarcoma tumors

    International Nuclear Information System (INIS)

    Postirradiation tumor volume response, cellular repopulation dynamics, cell-cycle perturbations, and phase-specific cell survival were characterized in rat rhabdomyosarcoma R-1 tumors (the R2C5 subline) following an in situ 10-Gy dose of 225-kVp X rays. This X-ray dose produced a 7.5-day delay in tumor growth to twice the volume measured at the time of irradiation, and reduced the initial surviving fraction of R2C5 cells to 0.17 as measured by the excision assay procedure. The surviving fraction of R2C5 cells returned to unity by the 16th day after tumor irradiation. On the basis of flow cytometry measurements of DNA content in tumor cells stained with a noncytotoxic concentration of Hoechst 33342, a transient G2 block was observed 1 day after irradiation. Flow cytometry measurements also demonstrated that the tetraploid R2C5 cells constituted only 30% of the total tumor cell population, with the remainder being diploid host cells comprised of macrophages, monocytes, lymphocytes, and granulocytes. Large numbers of host cells infiltrated the irradiated tumors, leading to an increase in the percentage of diploid cells by Day 2 and reaching a level of more than 80% of the total tumor cell population by 4 to 8 days after irradiation. The influx of host cells into irradiated tumors was correlated temporally with a significant 12-fold decrease in the surviving fraction of R2C5 cells that occurred between Days 2 and 4 postirradiation. When the diploid host cell population was removed by cell sorting procedures, the surviving fraction of R2C5 cells at Day 4 substantially greater than that in the presence of the host cells. Experiments involving the mixing of 4/1 and 12/1 ratios of diploid host cells and tetraploid tumor cells isolated from irradiated and unirradiated tumors demonstrated that the cytotoxic effect of the host cells was specific for the irradiated tumor cells

  14. Memory lineage relationships in HTLV-1-specific CD8+ cytotoxic T cells

    Science.gov (United States)

    Johnson-Nauroth, Julie M.; Graber, Jerome; Yao, Karen; Jacobson, Steve; Calabresi, Peter A.

    2016-01-01

    Cytotoxic memory T cells play a critical role in combating viral infections; however, in some diseases they may contribute to tissue damage. In HAM/TSP, HTLV-1 Tax 11–19+ cells proliferate spontaneously in vitro and can be tracked using the Tax 11–19 MHC Class I tetramer. Immediately ex vivo, these cells were a mix of CD45RA−/CCR7− TEM and CD45RA+/CCR7− TDiff memory CTL. The subsequent proliferating Tax 11–19 tetramer+ population expressed low levels of IL-7Rα, failed to respond to IL-7 and IL-15, and did not develop a TCM phenotype. Thus, chronic exposure to viral antigen may result in a sustained pool of TEM cells that home to the CNS and mediate the spinal cord pathology seen in this disease. PMID:16740321

  15. Cell-specific oxidative stress and cytotoxicity after wildfire coarse particulate matter instillation into mouse lung

    International Nuclear Information System (INIS)

    Our previous work has shown that coarse particulate matter (PM10-2.5) from wildfire smoke is more toxic to lung macrophages on an equal dose (by mass) basis than coarse PM isolated from normal ambient air, as evidenced by decreased numbers of macrophages in lung lavage fluid 6 and 24 hours after PM instillation into mouse lungs in vivo and by cytotoxicity to a macrophage cell line observed directly in vitro. We hypothesized that pulmonary macrophages from mice instilled with wildfire coarse PM would undergo more cytotoxicity than macrophages from controls, and that there would be an increase in oxidative stress in their lungs. Cytotoxicity was quantified as decreased viable macrophages and increased percentages of dead macrophages in the bronchoalveolar lavage fluid (BALF) of mice instilled with wildfire coarse PM. At 1 hour after PM instillation, we observed both decreased numbers of viable macrophages and increased dead macrophage percentages as compared to controls. An increase in free isoprostanes, an indicator of oxidative stress, from control values of 28.1 ± 3.2 pg/mL to 83.9 ± 12.2 pg/mL was observed a half-hour after PM instillation. By 1 hour after PM instillation, isoprostane values had returned to 30.4 ± 7.6 pg/mL, not significantly different from control concentrations. Lung sections from mice instilled with wildfire coarse PM showed rapid Clara cell responses, with decreased intracellular staining for the Clara cell secretory protein CCSP 1 hour after wildfire PM instillation. In conclusion, very rapid cytotoxicity occurs in pulmonary macrophages and oxidative stress responses are seen 0.5–1 hour after wildfire coarse PM instillation. These results define early cellular and biochemical events occurring in vivo and support the hypothesis that oxidative stress-mediated macrophage toxicity plays a key role in the initial response of the mouse lung to wildfire PM exposure. -- Highlights: ► We studied very early events (0.5–1 hour) after giving

  16. Dengue virus-specific, human CD4+ CD8- cytotoxic T-cell clones: multiple patterns of virus cross-reactivity recognized by NS3-specific T-cell clones.

    OpenAIRE

    Kurane, I; Brinton, M A; Samson, A L; Ennis, F A

    1991-01-01

    Thirteen dengue virus-specific, cytotoxic CD4+ CD8- T-cell clones were established from a donor who was infected with dengue virus type 3. These clones were examined for virus specificity and human leukocyte antigen (HLA) restriction in cytotoxic assays. Six patterns of virus specificities were determined. Two serotype-specific clones recognized only dengue virus type 3. Two dengue virus subcomplex-specific clones recognized dengue virus types 2, 3, and 4, and one subcomplex-specific clone re...

  17. A new cell line for high throughput HIV-specific antibody-dependent cellular cytotoxicity (ADCC) and cell-to-cell virus transmission studies

    Science.gov (United States)

    Orlandi, Chiara; Flinko, Robin; Lewis, George K.

    2016-01-01

    Several lines of evidence indicate that antibody-dependent cellular cytotoxicity (Wren et al., 2013) is important in the pathogenesis of HIV-1 infection. Namely, ADCC is induced during natural HIV-1 infection or in HIV-1 vaccine studies, the latter demonstrated by the RV144 vaccine trial. To expedite the assessment of ADCC in studies of HIV, we have developed a high throughput assay. We have optimized the rapid fluorometric antibody-mediated cytotoxicity assay (RFADCC) by transfecting the EGFP-CEM-NKr cell line to constitutively express SNAP-tagged CCR5. This cell line can then serve as a source of HIV-specific targets when coated with monomeric gp120, spinoculated with inactivated intact virions, infected by cell-free viral diffusion or infected by cell-to-cell transmission of virus. The optimized strategy has two significant advantages over the original RFADCC method: First, the preparation of detectable target cells is less labor intensive and faster as it does not rely on multiple staining and washing steps for target cells. Second, because the target cell markers GFP and SNAP are constitutively expressed, the assay provides highly reproducible data. These strengths make the optimized RFADCC assay suitable not only for studies of HIV-1 specific cytotoxicity but also for studies of cell–cell transmission of virus. In conclusion, this assay provides a new generation T cell line that can expedite large clinical studies as well as research studies in humans or non-human primates. PMID:26969387

  18. A novel system of artificial antigen-presenting cells efficiently stimulates Flu peptide-specific cytotoxic T cells in vitro

    International Nuclear Information System (INIS)

    Highlights: → Adoptive immunotherapy depends on relevant numbers of cytolytic T lymphocytes. → An ideal artificial APCs system was successfully prepared in vivo. → Controlled release of IL-2 leads to much more T-cell expansion. → This system is better than general cellular APCs on T-cell expansion. -- Abstract: Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

  19. A novel system of artificial antigen-presenting cells efficiently stimulates Flu peptide-specific cytotoxic T cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hui [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Peng, Ji-Run, E-mail: pengjr@medmail.com.cn [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Chen, Peng-Cheng; Gong, Lei [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Qiao, Shi-Shi [Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhengzhou University, Zhengzhou 450052 (China); Wang, Wen-Zhen; Cui, Zhu-Qingqing; Yu, Xin; Wei, Yu-Hua [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Leng, Xi-Sheng, E-mail: lengxs2003@yahoo.com.cn [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China)

    2011-08-05

    Highlights: {yields} Adoptive immunotherapy depends on relevant numbers of cytolytic T lymphocytes. {yields} An ideal artificial APCs system was successfully prepared in vivo. {yields} Controlled release of IL-2 leads to much more T-cell expansion. {yields} This system is better than general cellular APCs on T-cell expansion. -- Abstract: Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

  20. Application of magnetic field hyperthermia and superparamagnetic iron oxide nanoparticles to HIV-1-specific T-cell cytotoxicity

    Science.gov (United States)

    Williams, James P; Southern, Paul; Lissina, Anya; Christian, Helen C; Sewell, Andrew K; Phillips, Rodney; Pankhurst, Quentin; Frater, John

    2013-01-01

    The latent HIV-1 reservoir remains the major barrier to HIV-1 eradication. Although successful at limiting HIV replication, highly active antiretroviral therapy is unable to cure HIV infection, thus novel therapeutic strategies are needed to eliminate the virus. Magnetic field hyperthermia (MFH) generates thermoablative cytotoxic temperatures in target-cell populations, and has delivered promising outcomes in animal models, as well as in several cancer clinical trials. MFH has been proposed as a strategy to improve the killing of HIV-infected cells and for targeting the HIV latent reservoirs. We wished to determine whether MFH could be used to enhance cytotoxic T-lymphocyte (CTL) targeting of HIV-infected cells in a proof-of-concept study. Here, for the first time, we apply MFH to an infectious disease (HIV-1) using the superparamagnetic iron oxide nanoparticle FeraSpin R. We attempt to improve the cytotoxic potential of T-cell receptor-transfected HIV-specific CTLs using thermotherapy, and assess superparamagnetic iron oxide nanoparticle toxicity, uptake, and effect on cell function using more sensitive methods than previously described. FeraSpin R exhibited only limited toxicity, demonstrated efficient uptake and cell-surface attachment, and only modestly impacted T-cell function. In contrast to the cancer models, insufficient MFH was generated to enhance CTL killing of HIV-infected cells. MFH remains an exciting new technology in the field of cancer therapeutics, which, as technology improves, may have significant potential to enhance CTL function and act as an adjunctive therapy in the eradication of latently infected HIV-positive cells. PMID:23901272

  1. Restriction specificity of virus-specific cytotoxic T cells from thymectomised irradiated bone marrow chimeras reconstituted with thymus grafts

    International Nuclear Information System (INIS)

    Adult-thymectomised lethally irradiated mice A that were reconstituted with T-cell-depleted bone marrow cells of (A X B)F1 origin plus fetal thymus grafts of (B X C)F1 origin generated virus-specific T cells restricted to B alone; adult-thymectomised and lethally irradiated (A X B)F1 mice that were reconstituted with T-cell depleted bone marrow cells of (A X B)F1 origin plus fetal thymus grafts of A and of B origin generated virus-specific T cells restricted to A or to B. These results do not reveal obvious suppressive influences of host or stem-cell origin that might have explained results obtained with various irradiated bone marrow or thymus chimeras, they indicate that the thymus' influence on maturing T cells is one of the limiting steps in the selection of T cells' restriction specificities. (Auth.)

  2. Dendritic cells transduced with Rsf-1/HBXAP gene generate specific cytotoxic T lymphocytes against ovarian cancer in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Li [Department of Gynecology Oncology, Shan Dong Tumor Hospital, Jinan, Shandong (China); Department of Obstetrics and Gynecology, Qilu Hospital, Shandong University, Jinan, Shandong (China); Kong, Beihua, E-mail: kongbeihua@sdu.edu.cn [Department of Obstetrics and Gynecology, Qilu Hospital, Shandong University, Jinan, Shandong (China); Sheng, Xiugui [Department of Gynecology Oncology, Shan Dong Tumor Hospital, Jinan, Shandong (China); Sheu, Jim Jinn-Chyuan [Human Genetic Center, China Medical University Hospital and Graduate Institute of Chinese Medical Science, China Medical University, Taichung City, Taiwan (China); Shih, Ie-Ming [Departments of Pathology, Oncology, and Gynecology and Obstetrics, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States)

    2010-04-09

    Recently, some studies have indicated that Rsf-1/HBXAP plays a role in chromatin remodeling and transcriptional regulation that may contribute to tumorigenesis in ovarian cancer. The present study demonstrates that using dendritic cells (DCs) from human cord blood CD34{sup +} cells transduced with Rsf-1/HBXAP DNA plasmids by nucleofection generate specific cytotoxic T lymphocytes (CTL) against ovarian cancer in vitro. After transfection, DCs were analyzed for Rsf-1/HBXAP mRNA expression by RT-PCR and protein expression by Western blot. Then the DC phenotypes, T-cell stimulatory capacity, endocytic activity and migration capacity were explored by flow cytometry analysis, allogeneic mixed lymphocyte reaction, endocytosis and transwell chemotaxis assay, respectively. After transfection, Rsf-1/HBXAP expression was detected at mRNA and protein levels. Allogeneic T-cell proliferation induced by transfected DCs was obviously higher than non-transfected DCs, but the endocytosis capacity and migratory ability were not different. Rsf-1/HBXAP gene-transduced DCs could induce antigen-specific CTL and generate a very potent cytotoxicity to OVCAR3 cells. These data suggest that Rsf-1/HBXAP gene-transduced DCs may be a potential adjuvant immunotherapy for ovarian cancer in clinical applications.

  3. Dendritic cells transduced with Rsf-1/HBXAP gene generate specific cytotoxic T lymphocytes against ovarian cancer in vitro

    International Nuclear Information System (INIS)

    Recently, some studies have indicated that Rsf-1/HBXAP plays a role in chromatin remodeling and transcriptional regulation that may contribute to tumorigenesis in ovarian cancer. The present study demonstrates that using dendritic cells (DCs) from human cord blood CD34+ cells transduced with Rsf-1/HBXAP DNA plasmids by nucleofection generate specific cytotoxic T lymphocytes (CTL) against ovarian cancer in vitro. After transfection, DCs were analyzed for Rsf-1/HBXAP mRNA expression by RT-PCR and protein expression by Western blot. Then the DC phenotypes, T-cell stimulatory capacity, endocytic activity and migration capacity were explored by flow cytometry analysis, allogeneic mixed lymphocyte reaction, endocytosis and transwell chemotaxis assay, respectively. After transfection, Rsf-1/HBXAP expression was detected at mRNA and protein levels. Allogeneic T-cell proliferation induced by transfected DCs was obviously higher than non-transfected DCs, but the endocytosis capacity and migratory ability were not different. Rsf-1/HBXAP gene-transduced DCs could induce antigen-specific CTL and generate a very potent cytotoxicity to OVCAR3 cells. These data suggest that Rsf-1/HBXAP gene-transduced DCs may be a potential adjuvant immunotherapy for ovarian cancer in clinical applications.

  4. Inhibition of the accumulation, in rat kidney allografts, of specific--but not nonspecific--cytotoxic cells by cyclosporine

    International Nuclear Information System (INIS)

    Rats receiving kidney allografts were divided into two groups--one was treated daily with an immunosuppressive dose of cyclosporine and the other group was left untreated. Five days after transplantation the cells infiltrating the grafts were extracted by enzymic treatment and tested in vitro for specific and nonspecific cytotoxicity in a 6-hr 51Cr release assay. Approximately 5 X 10(7) and 7 X 10(7) mononuclear cells per kidney were obtained, respectively, from healthy grafts excised from cyclosporine-treated hosts and from grafts undergoing unmodified rejection. Despite these similarities in yield the cells harvested from the grafts of the two groups showed very different cytolytic activity. Cells from both sources displayed comparable levels of nonspecific cytotoxicity, but only those obtained from grafts undergoing rejection were able to mediate specific target cell lysis. The relevance of these observations to the understanding of the mechanism of kidney allograft rejection in the rat and of the mode of action of cyclosporine are briefly discussed

  5. Identification of swine influenza virus epitopes and analysis of multiple specificities expressed by cytotoxic T cell subsets

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers; Breum, Solvej Østergaard; Riber, Ulla;

    2014-01-01

    Background: Major histocompatibility complex (MHC) class I peptide binding and presentation are essential for antigen-specific activation of cytotoxic T lymphocytes (CTLs) and swine MHC class I molecules, also termed swine leukocyte antigens (SLA), thus play a crucial role in the process that leads...... to elimination of viruses such as swine influenza virus (SwIV). This study describes the identification of SLA-presented peptide epitopes that are targets for a swine CTL response, and further analyses multiple specificities expressed by SwIV activated CTL subsets. Findings: Four SwIV derived...... peptides were identified as T cell epitopes using fluorescent influenza: SLA tetramers. In addition, multiple CTL specificities were analyzed using peptide sequence substitutions in two of the four epitope candidates analyzed. Interestingly both conserved and substituted peptides were found to stain the CD...

  6. Differential activation of proliferation and cytotoxicity in human T-cell lymphotropic virus type I Tax-specific CD8 T cells by an altered peptide ligand.

    OpenAIRE

    Höllsberg, P; Weber, W E; Dangond, F; Batra, V; Sette, A.; Hafler, D A

    1995-01-01

    Human T-cell leukemia virus type I (HTLV-I) gives rise to a neurologic disease known as HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although the pathogenesis of the disease is unknown, the presence of a remarkably high frequency of Tax-specific, cytotoxic CD8 T cells may suggest a role of these cells in the development of HAM/TSP. Antigen-mediated signaling in a CD8 T-cell clone specific for the Tax(11-19) peptide of HTLV-I was studied using analog peptides substitute...

  7. Measurement of HCV-Specific CD8(+) Cytotoxic T-Cell Activities in the Peripheral Blood by Europium Release Assay.

    Science.gov (United States)

    Imawari, M

    1999-01-01

    Peripheral blood mononuclear cells (PBMC) contain NK cells, cytotoxic T-lymphocytes (CTL), helper T-cells, and B-cells that respond to viral infection and act to eliminate the virus from infected individuals. CTLs are not only thought to be a major host defense against viral infection, but are also implicated in the immunopathogenesis. Classical CTLs are CD8(+) and recognize endogenously synthesized and processed antigen in association with a human leukocyte antigen (HLA) class I molecule. The antigens are usually 8-10 amino acids long. HCV-specific CTLs have been demonstrated in the peripheral blood of some of patients with HCV infection by stimulating PBMC with the HCV synthetic peptides (1). The peptides were synthesized as overlapping peptides to encompass a certain region of the HCV antigen (1), on the basis of antigenicity prediction from the amino acid composition of HCV (2), or on the basis of the HLA binding motifs in the HCV antigen (3). Several minimal and optimal epitopes in the HCV antigen and their HLA restriction of recognition by CTLs have been defined. Recently, it has been reported that HCV-specific CTLs may suppress the outgrowth of HCV (4). In this chapter, methods will be discussed that demonstrate HCV-specific CTLs in the peripheral blood of patients with HCV infection. We use nonradioisotope europium (Eu) for assay of CTL activities. PMID:21374383

  8. Induction of Foot-and-Mouth Disease Virus-Specific Cytotoxic T Cell Killing by Vaccination

    DEFF Research Database (Denmark)

    Patch, J.R.; Pedersen, Lasse Eggers; Toka, F.N.;

    2011-01-01

    Foot-and-mouth disease (FMD) continues to be a significant threat to the health and economic value of livestock species. This acute infection is caused by the highly contagious FMD virus (FMDV), which infects cloven-hoofed animals including large and small ruminants and swine. Current vaccine...... cytopathic virus. Here, we have used recombinant human adenovirus vectors as a means of delivering FMDV antigens in a T cell-directed vaccine in pigs. We tested the hypothesis that impaired processing of the FMDV capsid would enhance cytolytic activity, presumably by targeting all proteins for degradation...... and effectively increasing the class I MHC/FMDV peptide concentration for stimulation of a CTL response. We compared such a T cell targeting vaccine with the parental vaccine, previously shown to effectively induce a neutralizing antibody response. Our results show induction of FMDV-specific CD8(+) CTL killing...

  9. Tumor-specific cytotoxic t cells are crucial for efficacy of immunomodulatory antibodies in patients with lung cancer

    NARCIS (Netherlands)

    J.G.J.V. Aerts (Joachim); J.P.J.J. Hegmans (Joost)

    2013-01-01

    textabstractThere is growing evidence that activation of the immune system may be an effective treatment for patients with either small cell lung cancer or non-small cell lung cancer (NSCLC). Immunomodulatory antibodies directed against cytotoxic T cell-associated antigen 4 (CTLA-4/CD152) and progra

  10. Frankincense oil derived from Boswellia carteri induces tumor cell specific cytotoxicity

    Directory of Open Access Journals (Sweden)

    Ashley Richard A

    2009-03-01

    Full Text Available Abstract Background Originating from Africa, India, and the Middle East, frankincense oil has been important both socially and economically as an ingredient in incense and perfumes for thousands of years. Frankincense oil is prepared from aromatic hardened gum resins obtained by tapping Boswellia trees. One of the main components of frankincense oil is boswellic acid, a component known to have anti-neoplastic properties. The goal of this study was to evaluate frankincense oil for its anti-tumor activity and signaling pathways in bladder cancer cells. Methods Frankincense oil-induced cell viability was investigated in human bladder cancer J82 cells and immortalized normal bladder urothelial UROtsa cells. Temporal regulation of frankincense oil-activated gene expression in bladder cancer cells was identified by microarray and bioinformatics analysis. Results Within a range of concentration, frankincense oil suppressed cell viability in bladder transitional carcinoma J82 cells but not in UROtsa cells. Comprehensive gene expression analysis confirmed that frankincense oil activates genes that are responsible for cell cycle arrest, cell growth suppression, and apoptosis in J82 cells. However, frankincense oil-induced cell death in J82 cells did not result in DNA fragmentation, a hallmark of apoptosis. Conclusion Frankincense oil appears to distinguish cancerous from normal bladder cells and suppress cancer cell viability. Microarray and bioinformatics analysis proposed multiple pathways that can be activated by frankincense oil to induce bladder cancer cell death. Frankincense oil might represent an alternative intravesical agent for bladder cancer treatment.

  11. Herpes simplex virus (HSV)-specific proliferative and cytotoxic T-cell responses in humans immunized with an HSF type 2 glycoprotein subunit vaccine

    International Nuclear Information System (INIS)

    Studies were undertaken to determine whether immunization of humans with a herpes simplex virus type 2 (HSV-2) glycoprotein-subunit vaccine would result in the priming of both HSV-specific proliferating cells and cytotoxic T cells. Peripheral blood lymphocytes (PBL) from all eight vaccinees studied responded by proliferating after stimulation with HSV-2, HSV-1, and glycoprotein gB-1. The PBL of five of these eight vaccinees proliferated following stimulation with gD-2, whereas stimulation with Gd-1 resulted in relatively low or no proliferative responses. T-cell clones were generated from HSV-2-stimulated PBL of three vaccinees who demonstrated strong proliferative responses to HSV-1 and HSV-2. Of 12 clones studied in lymphoproliferative assays, 9 were found to be cross-reactive for HSV-1 and HSV-2. Of the approximately 90 T-cell clones isolated, 14 demonstrated HSV-specific cytotoxic activity. Radioimmunoprecipitation-polyacrylamide gel electrophoresis analyses confirmed that the vaccinees had antibodies only to HSV glycoproteins, not to proteins which are absent in the subunit vaccine, indicating that these vaccinees had not become infected with HSV. Immunization of humans with an HSV-2 glycoprotein-subunit vaccine thus results in the priming of T cells that proliferate in response to stimulation with HSV and its glycoproteins and T cells that have cytotoxic activity against HSV-infected cells. Such HSV-specific memory T cells were detected as late as 2 years following the last boost with the subunit vaccine

  12. Induction of CML28-specific cytotoxic T cell responses using co-transfected dendritic cells with CML28 DNA vaccine and SOCS1 small interfering RNA expression vector

    International Nuclear Information System (INIS)

    CML28 is an attractive target for antigen-specific immunotherapy. SOCS1 represents an inhibitory control mechanism for DC antigen presentation and the magnitude of adaptive immunity. In this study, we evaluated the potential for inducing CML28-specific cytotoxic T lymphocytes (CTL) responses by dendritic cells (DCs)-based vaccination. We constructed a CML28 DNA vaccine and a SOCS1 siRNA vector and then cotransfect monocyte-derived DCs. Flow cytometry analysis showed gene silencing of SOCS1 resulted in higher expressions of costimulative moleculars in DCs. Mixed lymphocyte reaction (MLR) indicated downregulation of SOCS1 stronger capability to stimulate proliferation of responder cell in DCs. The CTL assay revealed transfected DCs effectively induced autologous CML28-specific CTL responses and the lytic activities induced by SOCS1-silenced DCs were significantly higher compared with those induced by SOCS1-expressing DCs. These results in our study indicates gene silencing of SOCS1 remarkably enhanced the cytotoxicity efficiency of CML28 DNA vaccine in DCs

  13. A Peptide mimicking a region in proliferating cell nuclear antigen specific to key protein interactions is cytotoxic to breast cancer.

    Science.gov (United States)

    Smith, Shanna J; Gu, Long; Phipps, Elizabeth A; Dobrolecki, Lacey E; Mabrey, Karla S; Gulley, Pattie; Dillehay, Kelsey L; Dong, Zhongyun; Fields, Gregg B; Chen, Yun-Ru; Ann, David; Hickey, Robert J; Malkas, Linda H

    2015-02-01

    Proliferating cell nuclear antigen (PCNA) is a highly conserved protein necessary for proper component loading during the DNA replication and repair process. Proteins make a connection within the interdomain connector loop of PCNA, and much of the regulation is a result of the inherent competition for this docking site. If this target region of PCNA is modified, the DNA replication and repair process in cancer cells is potentially altered. Exploitation of this cancer-associated region has implications for targeted breast cancer therapy. In the present communication, we characterize a novel peptide (caPeptide) that has been synthesized to mimic the sequence identified as critical to the cancer-associated isoform of PCNA. This peptide is delivered into cells using a nine-arginine linking mechanism, and the resulting peptide (R9-cc-caPeptide) exhibits cytotoxicity in a triple-negative breast cancer cell line, MDA-MB-436, while having less of an effect on the normal counterparts (MCF10A and primary breast epithelial cells). The novel peptide was then evaluated for cytotoxicity using various in vivo techniques, including ATP activity assays, flow cytometry, and clonogenetic assays. This cytotoxicity has been observed in other breast cancer cell lines (MCF7 and HCC1937) and other forms of cancer (pancreatic and lymphoma). R9-cc-caPeptide has also been shown to block the association of PCNA with chromatin. Alanine scanning of the peptide sequence, combined with preliminary in silico modeling, gives insight to the disruptive ability and the molecular mechanism of action of the therapeutic peptide in vivo. PMID:25480843

  14. Cytomegalovirus Infection Leads to Development of High Frequencies of Cytotoxic Virus-Specific CD4+ T Cells Targeted to Vascular Endothelium.

    Science.gov (United States)

    Pachnio, Annette; Ciaurriz, Miriam; Begum, Jusnara; Lal, Neeraj; Zuo, Jianmin; Beggs, Andrew; Moss, Paul

    2016-09-01

    Cytomegalovirus (CMV) infection elicits a very strong and sustained intravascular T cell immune response which may contribute towards development of accelerated immune senescence and vascular disease in older people. Virus-specific CD8+ T cell responses have been investigated extensively through the use of HLA-peptide tetramers but much less is known regarding CMV-specific CD4+ T cells. We used a range of HLA class II-peptide tetramers to investigate the phenotypic and transcriptional profile of CMV-specific CD4+ T cells within healthy donors. We show that such cells comprise an average of 0.45% of the CD4+ T cell pool and can reach up to 24% in some individuals (range 0.01-24%). CMV-specific CD4+ T cells display a highly differentiated effector memory phenotype and express a range of cytokines, dominated by dual TNF-α and IFN-γ expression, although substantial populations which express IL-4 were seen in some donors. Microarray analysis and phenotypic expression revealed a profile of unique features. These include the expression of CX3CR1, which would direct cells towards fractalkine on activated endothelium, and the β2-adrenergic receptor, which could permit rapid response to stress. CMV-specific CD4+ T cells display an intense cytotoxic profile with high level expression of granzyme B and perforin, a pattern which increases further during aging. In addition CMV-specific CD4+ T cells demonstrate strong cytotoxic activity against antigen-loaded target cells when isolated directly ex vivo. PD-1 expression is present on 47% of cells but both the intensity and distribution of the inhibitory receptor is reduced in older people. These findings reveal the marked accumulation and unique phenotype of CMV-specific CD4+ T cells and indicate how such T cells may contribute to the vascular complications associated with CMV in older people. PMID:27606804

  15. Gene-engineered varicella-zoster virus reactive CD4+ cytotoxic T cells exert tumor-specific effector function.

    Science.gov (United States)

    Landmeier, Silke; Altvater, Bianca; Pscherer, Sibylle; Eing, Bodo R; Kuehn, Joachim; Rooney, Cliona M; Juergens, Heribert; Rossig, Claudia

    2007-09-01

    T cells with grafted specificities for surface antigens provide an avenue for rapidly producing immune effector cells with tumor specificity. However, the function of chimeric receptor (chRec) gene-modified T cells is limited by lack of T-cell expansion and persistence. We propose to use varicella zoster virus (VZV)-reactive T cells as host for the chRec because these cells can be expanded both in vitro and in vivo by stimulation of their native receptor during endogenous reexposure to the virus or by administration of VZV vaccine. We obtained human T cells reactive with VZV from the peripheral blood of seropositive donors by stimulation with VZV lysate and evaluated their characteristics after genetic modification with two tumor-specific model chRecs. Cultures dominated by cytolytic CD4(+) T cells (VZV-CTL) could be expanded and maintained in vitro. Gene-modified VZV-CTL recognized and lysed tumor targets in a MHC-independent manner while maintaining functional, MHC-restricted interaction with VZV antigen through their native receptor. Thus, chRec-transduced VZV-CTL may provide a source of potent tumor-reactive cells for adoptive immunotherapy of cancer. The availability of a safe and effective VZV vaccine provides the option of repeated in vivo stimulation to maintain high T-cell numbers until the tumor is eliminated. PMID:17804749

  16. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART)

    DEFF Research Database (Denmark)

    Skov Jensen, Sanne; Fomsgaard, Anders; Borggren, Marie; Tingstedt, Jeanette Linnea; Gerstoft, Jan; Kronborg, Gitte; Rasmussen, Line Dahlerup; Pedersen, Court; Karlsson, Ingrid

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated...... the ability of effector cells and antibodies to mediate ADCC separately and in combination using the ADCC-PanToxiLux assay. The ability of the peripheral blood mononuclear cells (PBMCs) to mediate ADCC was significantly higher in individuals who had been treated with ART before seroconversion......, compared to the individuals initiating ART at a low CD4+ T cell count (<350 cells/μl blood) and the ART-naïve individuals. The frequency of CD16 expressing natural killer (NK) cells correlated with both the duration of ART and Granzyme B (GzB) activity. In contrast, the plasma titer of antibodies mediating...

  17. Development of skewed functionality of HIV-1-specific cytotoxic CD8(+ T cells from primary to early chronic phase of HIV infection.

    Directory of Open Access Journals (Sweden)

    Wanhai Wang

    Full Text Available In recent years, the prevalence of HIV-1 infection has been rapidly increasing among men who have sex with men (MSM. However, it remains unknown how the host immune system responds to the infection in this population. We assessed the quantity of HIV-specific CD8(+ T-cell responses by using Elispot assay and their functionalities by measuring 5 CD8(+ T-cell evaluations (IL-2, MIP-1β, CD107a, TNF-α, IFN-γ with flow cytometry assays among 18 primarily and 37 early chronically HIV-infected MSM. Our results demonstrated that subjects at early chronic phase developed HIV-specific CD8(+ T-cell responses with higher magnitudes and more diversified functionalities in comparison with those at primary infection. However, populations with IL-2(+ CD107a(+ or in combination with other functionality failed to develop in parallel. The multifunctional but not monofunctional HIV-specific CD8(+ T cells were associated with higher CD4(+ T -cell counts and lower viral loads. These data revealed that prolonged infection from primary to early chronic infection could selectively increase the functionalities of HIV-specific CD8(+ T cells in HIV-infected MSM population, the failure to develop IL-2 and cytotoxic functionalities in parallel may explain why the increased HIV-specific CD8(+ T cells were unable to enhance the containment of HIV-1 replication at the early chronic stage.

  18. Induction of Cytotoxic T Lymphocytes Specific to Malignant Glioma Using T2 Cells Pulsed with HLA-A2-restricted Interleukin-13 Receptor α2 Peptide in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Interleukin-13 receptor α2 (IL-13Rα2) is a glioma-restricted cell-surface epitope not otherwise detected within the central nervous system. The present study is a report of a novel approach of targeting malignant glioma with IL-13Rα2-specific cytotoxic T lymphocyte (CTL) induced from the peripheral blood mononuclear cells of healthy donors by multiple stimulations with human leukocyte antigen(HLA)-A2-restricted IL-13Rα2345-353 peptide-pulsed T2 cells. The induced CTL showed specific lysis against T2 cells pulsed with the peptide and HLA-A2+ glioma cells expressing IL-13Rα2345-353, while HLA-A2 glioma cell lines that express IL-13Rα2345-353 could not be recognized by CTL. The peptide-specific activity was inhibited by anti-HLA class Ⅰ monoclonal antibody. These results suggest that the induced CTL specific for IL-13Rα2345-353 peptide could be a potential target of specific immunotherapy for HLA-A2 patients with malignant glioma.

  19. Induction/Engineering, Detection, Selection, and Expansion of Clinical-Grade Human Antigen-Specific CD8+ Cytotoxic T Cell Clones for Adoptive Immunotherapy

    Directory of Open Access Journals (Sweden)

    Matjaž Jeras

    2010-01-01

    Full Text Available Adoptive transfer of effector antigen-specific immune cells is becoming a promising treatment option in allogeneic transplantation, infectious diseases, cancer, and autoimmune disorders. Within this context, the important role of CD8+ cytotoxic T cells (CTLs is objective of intensive studies directed to their in vivo and ex vivo induction, detection, selection, expansion, and therapeutic effectiveness. Additional questions that are being addressed by the scientific community are related to the establishment and maintenance of their longevity and memory state as well as to defining critical conditions underlying their transitions between discrete, but functionally different subtypes. In this article we review and comment latest approaches and techniques used for preparing large amounts of antigen-specific CTLs, suitable for clinical use.

  20. Dendritic cells engineered to express defined allo-HLA peptide complexes induce antigen-specific cytotoxic T cells efficiently killing tumour cells

    DEFF Research Database (Denmark)

    Stronen, E; Abrahamsen, I W; Gaudernack, G; Wälchli, S; Munthe, E; Buus, S; Johansen, F-E; Lund-Johansen, F; Olweus, J

    2009-01-01

    , efficiently present externally loaded peptides from the antigen, Melan-A/MART-1 to T cells from HLA-A*0201-negative donors. CD8(+) T cells binding HLA-A*0201/MART-1 pentamers were detected already after 12 days of co-culture in 11/11 donors. The majority of cells from pentamer(+) cell lines were CTL and...... efficiently killed HLA-A*0201(+) melanoma cells, whilst sparing HLA-A*0201(+) B-cells. Allo-restricted CTL specific for peptides from the leukaemia-associated antigens CD33 and CD19 were obtained with comparable efficiency. Collectively, the results show that dendritic cells engineered to express defined allo...

  1. Induction of Foot-and-Mouth Disease Virus-Specific Cytotoxic T Cell Killing by Vaccination ▿ §

    OpenAIRE

    Patch, Jared R; Pedersen, Lasse E.; Toka, Felix N.; Moraes, Mauro; Grubman, Marvin J.; Nielsen, Morten; Jungersen, Gregers; Buus, Soren; Golde, William T.

    2010-01-01

    Foot-and-mouth disease (FMD) continues to be a significant threat to the health and economic value of livestock species. This acute infection is caused by the highly contagious FMD virus (FMDV), which infects cloven-hoofed animals, including large and small ruminants and swine. Current vaccine strategies are all directed toward the induction of neutralizing antibody responses. However, the role of cytotoxic T lymphocytes (CTLs) has not received a great deal of attention, in part because of th...

  2. Protective effects of ion-imprinted chitooligosaccharides as uranium-specific chelating agents against the cytotoxicity of depleted uranium in human kidney cells

    International Nuclear Information System (INIS)

    Occupational internal contamination with depleted uranium (DU) compounds can induce radiological and chemical toxicity, and an effective and specific uranium-chelating agent for clinical use is urgently needed. The purpose of this study was to investigate whether a series of synthesized water-soluble metal-ion-imprinted chitooligosaccharides can be used as uranium-specific chelating agents, because the chitooligosaccharides have excellent heavy metal ion chelation property and the ion-imprinting technology can improve the selective recognition of template ions. DU-poisoned human renal proximal tubule epithelium cells (human kidney 2 cells, HK-2) were used to assess the detoxification of these chitooligosaccharides. The DU-chelating capacity and selectivity of the chitooligosaccharides were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Cell viability, cellular accumulation of DU, membrane damage, DNA damage, and morphological changes in the cellular ultrastructure were examined to assess the detoxification of these chitooligosaccharides. The results showed that the Cu2+-imprinted chitooligosaccharides, especially the Cu2+-imprinted glutaraldehyde-crosslinked carboxymethyl chitooligosaccharide (Cu-Glu-CMC), chelated DU effectively and specifically, and significantly reduced the loss of cell viability induced by DU and reduced cellular accumulation of DU in a dose-dependent manner, owing to their chelation of DU outside cells and their prevention of DU internalization. The ultrastructure observation clearly showed that Cu-Glu-CMC-chelated-DU precipitates, mostly outside cells, were grouped in significantly larger clusters, and they barely entered the cells by endocytosis or in any other way. Treatment with Cu-Glu-CMC also increased the activity of antioxidant enzymes, and reduced membrane damage and DNA damage induced by DU oxidant injury. Cu-Glu-CMC was more effective than the positive control drug, diethylenetriaminepentaacetic acid (DTPA), in

  3. Human cytomegalovirus pp65- and immediate early 1 antigen-specific HLA class I-restricted cytotoxic T cell responses induced by cross-presentation of viral antigens.

    Science.gov (United States)

    Tabi, Z; Moutaftsi, M; Borysiewicz, L K

    2001-05-01

    Dendritic cells (DCs) play a pivotal role in the development of anti-viral CD8(+) CTL responses. This is straightforward if they are directly infected with virus, but is less clear in response to viruses that cannot productively infect DCS: Human CMV (HCMV) shows strain-specific cell tropism: fibroblast (Fb)-adapted laboratory strains (AD169) and recent clinical isolates do not infect DCs, whereas endothelial cell-adapted strains (TB40/E) result in productive lytic DC infection. However, we show here that uninfected DCs induce CD8(+) T cell cytotoxicity and IFN-gamma production against HCMV pp65 and immediate early 1 Ags following in vitro coculture with HCMV-AD169-infected Fbs, regardless of the HLA type of these FBS: CD8(+) T cell stimulation was inhibited by pretreatment of DCs with cytochalasin B or brefeldin A, indicating a phagosome/endosome to cytosol pathway. HCMV-infected Fbs were not apoptotic as measured by annexin V binding, and induction of apoptosis of infected Fbs in vitro did not augment CTL induction by DCs, suggesting a mechanism other than apoptosis in the initiation of cross-presentation. Furthermore, HCMV-infected Fbs provided a maturation signal for immature DCs during coculture, as evidenced by increased CD83 and HLA class II expression. Cross-presentation of HCMV Ags by host DCs enables these professional APCs to bypass some of the evasion mechanisms HCMV has developed to avoid T cell recognition. It may also serve to explain the presence of immediate early 1 Ag-specific CTLs in the face of pp65-induced inhibition of Ag presentation at the level of the infected cell. PMID:11313411

  4. HPV16E7-HSP70 Hybrid DNA Vaccine Induces E7-Specific Cytotoxic T Cells and Antitumor Immunity

    Institute of Scientific and Technical Information of China (English)

    ZHU Liqin; LI Hui; XIONG Jinhu; WANG Tongxiang; OU Xuan; WEI Yun; WU Xinxing

    2006-01-01

    Using human papillomavirus type 16 (HPV16) E7 as an antigen and Heat Shock Protein 70 as adjuvant, we constructed a DNA vaccine by linking HSP70 gene to E7C91G gene. Mice, after being immunized with E7C91G-HSP70, E7C91G/HSP70, E7C91G, and wild E7 DNA vaccines respectively, produced E7 specific CD8+ T-cell precursor frequencies oF280. 33±2.52, 144.34±4. 04, 164.34±5.13 and 82.33± 3.51 respectively within every 1 × 105 mouse splenocytes. This proves that E7C91G-HSP70 fusion vaccine can significantly enhance the E7 specific cellular immunity within the mice body(p<0.01). After being immunized with E7C91G-HSP70 fusion vaccine, tumor-bearing mice of the group being treated have significantly longer latency and survival periods, comparing with other three categories of E7 vaccines. Experiment shows that this vaccine has a significant effect on enhancing E7 positive tumor-treatment within mice body. After being immunized with E7C91G-HSP70 vaccine, there were no pathological changes found in livers, kidneys and spleens of the mice, which proves that the vaccine is quite safe. After all,E7C91G-HSP70 fusion vaccine has a much stronger tumor- treatment effect than that of wild type E7 DNA vaccine.

  5. Antigen-Specific Cytotoxic T Lymphocytes can Target Chemoresistant Side-Population Tumor Cells in Hodgkin’s Lymphoma

    OpenAIRE

    Shafer, Jessica A.; Cruz, Conrad R.; Leen, Ann M; Ku, Stephanie; LU, AN; Rousseau, Alexandra; Heslop, Helen E.; Rooney, Cliona M; Bollard, Catherine M.; Foster, Aaron E.

    2010-01-01

    Side-population (SP) analysis has been used to identify progenitor cells from normal and malignant tissues as well as revealing tumor cells with increased resistance to radiation and chemotherapy. Despite enhanced chemoresistance, tumor SP cells may still express tumor associated antigens (TAA) which may render them susceptible to elimination by the immune system. In this study, we show that both Hodgkin’s lymphoma (HL) cell lines and primary HL tumor samples contain a distinct SP phenotype. ...

  6. Graft-versus-leukemia effects of Wilms' tumor 1 protein-specific cytotoxic T lymphocytes in patients with chronic myeloid leukemia after allogeneic hematopoietic stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-dong; LI Dan; HUANG Xiao-jun

    2010-01-01

    Background The role of Wilms' tumor 1 protein (WT1)-specific cytotoxic T cells (CTL) in eradicating chronic myeloid leukemia (CML) cells is to be established. The aim of this study was to determine whether WT1 contributed to the graft-versus-leukemia effects (GVLE) for CML following allogeneic hematopoietic stem cell transplantation (HSCT). Methods High-resolution human leukocyte antigen (HLA) class I genotyping was performed by sequence-specific polymerase chain reaction (PCR). Fifteen HLA-A~*2402 patients with CML who underwent allogeneic HSCT were enrolled in this study. We monitored the frequency of WT1-specific CTL by pentamer assay and the molecular minimal residual disease by real-time quantitative PCR.Results A CD8~+ T-cell response to WT1 was observed in 14 of 15 patients after HSCT. The median frequencies of WT1-CTL were 0.54%, 0.62%, 0.81% and 1.28% (%CD8) on days 30, 60, 90 and 180, respectively. The median frequency of WT1-CTL (1.38%) in patients with molecular remission (MoR) was significantly higher than that in those without MoR (0.38%) on day 30, while no significant differences between them were detected on days 60, 90 and 180. The increase of WT1-CTL was associated with a decrease in bcr-abl expression and MoR; and the decrease of WT1-CTL was associated with an increase in bcr-abl expression, suggesting a WT1 -driven GVL effect. WT1-CTL had a predominant effector-memory phenotype (CD45RO~+CD27~-CD57~+).Conclusions The emergence of WT1-CTL with an effector-memory phenotype is associated with GVLE in CML patients after HSCT. This will pave the way for the WT1 vaccines to enhance GVLE after HSCT in CML.

  7. Relationship between serum HBV DNA level and HBV-specific,nonspecific cytotoxic T lymphocytes and natural killer cells in patients with chronic hepatitis B

    Institute of Scientific and Technical Information of China (English)

    GU Xi-bing; YANG Xiao-juan; WANG Dong; HUA Zhong; XU Yue-qin; LU Zhong-hua

    2009-01-01

    Background The response of patients with chronic hepatitis B (CHB) to antiviral therapy against hepatitis B virus (HBV) is related to the base line level of HBV DNA, but the mechanism is not clear. The present study aimed to understand the possible relationship between the level of HBV DNA and HBV-specific, nonspecific cytotoxic T lymphocytes (CTL) and natural killer (NK) cells of CHB patients and the mechanism how the HBV DNA level influences the antiviral therapeutic effect.Methods Totally 100 adult patients with CHB who were positive for HBV DNA, HBeAg and (HLA)-A2 were enrolled into this study. HBV DNA was tested by real time fluorescence quantitative polymerase chain reaction (PCR). HBV specific and nonspecific CTL and NK cells were tested by flowcytometry. Serum alanine aminotransferase (ALT) and total bilirubin (Tbil) were determined for each patient using routine biochemical tests. The 100 cases were assigned to two groups based on their HBV DNA level: group A had 48 cases, their HBV DNA level was 104-105 copies/ml, group B had 52 cases, their HBV DNA level was 106-107 copies/ml. HBV specific CTL, nonspecific CTL, NK cells, ALT and Tbil of the two groups were compared.Results HBV DNA level of groups A and B was (4.81±0.39) log10 copies/ml and (6.81±0.40) log10 copies/ml, respectively (t=25.32, P <0.001). HBV specific CTL and NK cells of group A were significantly higher than those of group B (P <0.001 for both). Nonspecific CTL of group A was significantly lower than that of group B (P <0.01). ALT and Tbil of group A were significantly lower than those of group B (P <0.01 and P <0.05, respectively).Conclusions Serum HBV DNA level of patients with CHB is related to HBV specific CTL, nonspecific CTL and NK cells, which might result in inflammatory reaction of liver and cause more damage to liver function. Mechanism of HBV DNA level affecting the efficacy of anti-viral treatment may be related to the levels of HBV specific CTL and NK cells.

  8. "False" cytotoxicity of ions-adsorbing hydroxyapatite - Corrected method of cytotoxicity evaluation for ceramics of high specific surface area.

    Science.gov (United States)

    Klimek, Katarzyna; Belcarz, Anna; Pazik, Robert; Sobierajska, Paulina; Han, Tomasz; Wiglusz, Rafal J; Ginalska, Grazyna

    2016-08-01

    An assessment of biomaterial cytotoxicity is a prerequisite for evaluation of its clinical potential. A material is considered toxic while the cell viability decreases under 70% of the control. However, extracts of certain materials are likely to reduce the cell viability due to the intense ions adsorption from culture medium (e.g. highly bioactive ceramics of high surface area). Thus, the standard ISO 10993-5 procedure is inappropriate for cytotoxicity evaluation of ceramics of high specific surface area because biomaterial extract obtained in this method (ions-depleted medium) is not optimal for cell cultures per se. Therefore, a simple test was designed as an alternative to ISO 10993-5 standard for cytotoxicity evaluation of the biomaterials of high surface area and high ions absorption capacity. The method, presented in this paper, included the evaluation of ceramics extract prepared according to corrected procedure. The corrected extract was found not cytotoxic (cell viability above 70%), suggesting that modified method for cytotoxicity evaluation of ions-adsorbing ceramics is more appropriate than ISO 10993-5 standard. For such biomaterials, the term "false" cytotoxicity is more suitable. Moreover, it was noted that NRU assay and microscopic observations should be recommended for cytotoxicity evaluation of ceramics of high surface area. PMID:27157729

  9. Identification of an MSI-H Tumor-Specific Cytotoxic T Cell Epitope Generated by the (−1 Frame of U79260(FTO

    Directory of Open Access Journals (Sweden)

    Michael Linnebacher

    2010-01-01

    Full Text Available Microsatellite instability (MSI-H induced by defects of the DNA mismatch repair system results in insertion or deletion of single nucleotides at short repetitive DNA sequences. About 15% of sporadic and approximately 90% of hereditary nonpolyposis colorectal cancers display MSI-H. When affecting coding regions, MSI-H results in frameshift mutations and expression of corresponding frameshift peptides (FSPs. Functional tumor promoting relevance has been demonstrated for a growing number of genes frequently hit by MSI-H. Contrary, immune reactions against FSPs are involved in the immune surveillance of MSI-H cancers. Here, we provide conclusive data that the (−1 frame of U79260(FTO encodes an HLA-A0201-restricted cytotoxic T cell epitope (FSP11; TLSPGWSAV. T cells specific for FSP11 efficiently recognized HLA-A0201(pos tumor cells harboring the mutated reading frame. Considering the exceptionally high mutation rate of U79260(FTO in MSI-H colorectal carcinoma (81.8%, this recommends that FSP11 be a component of future vaccines.

  10. CERT depletion predicts chemotherapy benefit and mediates cytotoxic and polyploid‐specific cancer cell death through autophagy induction

    DEFF Research Database (Denmark)

    Lee, Alvin J. X.; Roylance, Rebecca; Sander, Jil;

    2012-01-01

    . Live cell microscopy analysis revealed that CERT depletion induces LAMP2‐dependent death of polyploid cells following exit from mitosis in the presence of paclitaxel. We find that CERT is relatively over‐expressed in HER2+ breast cancer and CERT protein expression acts as an independent prognostic...

  11. Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT on human leukemia HL-60 cells

    Directory of Open Access Journals (Sweden)

    Jiang Pingping

    2010-04-01

    Full Text Available Abstract Background Polysaccharopeptide (PSP from Coriolus versicolor (Yunzhi is used as a supplementary cancer treatment in Asia. The present study aims to investigate whether PSP pre-treatment can increase the response of the human leukemia HL-60 cells to apoptosis induction by Camptothecin (CPT. Methods We used bivariate bromodeoxyuridine/propidium iodide (BrdUrd/PI flow cytometry analysis to measure the relative movement (RM of the BrdUrd positively labeled cells and DNA synthesis time (Ts on the HL-60 cell line. We used annexin V/PI flow cytometry analysis to quantify the viable, necrotic and apoptotic cells. The expression of cyclin E and cyclin B1 was determined with annexin V/PI flow cytometry and western blotting. Human peripheral blood mononuclear cells were used to test the cytotoxicity of PSP and CPT. Results PSP reduced cellular proliferation; inhibited cells progression through both S and G2 phase, reduced 3H-thymidine uptake and prolonged DNA synthesis time (Ts in HL-60 cells. PSP-pretreated cells enhanced the cytotoxicity of CPT. The sensitivity of cells to the cytotoxic effects of CPT was seen to be the highest in the S-phase and to a small extent of the G2 phase of the cell cycle. On the other hand, no cell death (measured by annexin V/PI was evident with the normal human peripheral blood mononuclear cells with treatment of either PSP or CPT. Conclusion The present study shows that PSP increases the sensitization of the HL-60 cells to undergo effective apoptotic cell death induced by CPT. The pattern of sensitivity of cancer cells is similar to that of HL-60 cells. PSP rapidly arrests and/or kills cells in S-phase and did not interfere with the anticancer action of CPT. PSP is a potential adjuvant to treat human leukemia as rapidly proliferating tumors is characterized by a high proportion of S-phase cells.

  12. A Peptide Mimicking a Region in Proliferating Cell Nuclear Antigen Specific to Key Protein Interactions Is Cytotoxic to Breast Cancer

    OpenAIRE

    Smith, Shanna J.; Gu, Long; Phipps, Elizabeth A.; Lacey E Dobrolecki; Mabrey, Karla S.; Gulley, Pattie; Dillehay, Kelsey L; Dong, Zhongyun; Fields, Gregg B.; Chen, Yun-Ru; Ann, David; Hickey, Robert J.; Malkas, Linda H.

    2015-01-01

    Proliferating cell nuclear antigen (PCNA) is a highly conserved protein necessary for proper component loading during the DNA replication and repair process. Proteins make a connection within the interdomain connector loop of PCNA, and much of the regulation is a result of the inherent competition for this docking site. If this target region of PCNA is modified, the DNA replication and repair process in cancer cells is potentially altered. Exploitation of this cancer-associated region has imp...

  13. Mechanism of Arctigenin-Induced Specific Cytotoxicity against Human Hepatocellular Carcinoma Cell Lines: Hep G2 and SMMC7721

    OpenAIRE

    Zheng Lu; Shengbo Cao; Hongbo Zhou; Ling Hua; Shishuo Zhang; Jiyue Cao

    2015-01-01

    Arctigenin (ARG) has been previously reported to exert high biological activities including anti-inflammatory, antiviral and anticancer. In this study, the anti-tumor mechanism of ARG towards human hepatocellular carcinoma (HCC) was firstly investigated. We demonstrated that ARG could induce apoptosis in Hep G2 and SMMC7721 cells but not in normal hepatic cells, and its apoptotic effect on Hep G2 was stronger than that on SMMC7721. Furthermore, the following study showed that ARG treatment le...

  14. Mechanism of Arctigenin-Induced Specific Cytotoxicity against Human Hepatocellular Carcinoma Cell Lines: Hep G2 and SMMC7721.

    Science.gov (United States)

    Lu, Zheng; Cao, Shengbo; Zhou, Hongbo; Hua, Ling; Zhang, Shishuo; Cao, Jiyue

    2015-01-01

    Arctigenin (ARG) has been previously reported to exert high biological activities including anti-inflammatory, antiviral and anticancer. In this study, the anti-tumor mechanism of ARG towards human hepatocellular carcinoma (HCC) was firstly investigated. We demonstrated that ARG could induce apoptosis in Hep G2 and SMMC7721 cells but not in normal hepatic cells, and its apoptotic effect on Hep G2 was stronger than that on SMMC7721. Furthermore, the following study showed that ARG treatment led to a loss in the mitochondrial out membrane potential, up-regulation of Bax, down-regulation of Bcl-2, a release of cytochrome c, caspase-9 and caspase-3 activation and a cleavage of poly (ADP-ribose) polymerase in both Hep G2 and SMMC7721 cells, suggesting ARG-induced apoptosis was associated with the mitochondria mediated pathway. Moreover, the activation of caspase-8 and the increased expression levels of Fas/FasL and TNF-α revealed that the Fas/FasL-related pathway was also involved in this process. Additionally, ARG induced apoptosis was accompanied by a deactivation of PI3K/p-Akt pathway, an accumulation of p53 protein and an inhibition of NF-κB nuclear translocation especially in Hep G2 cells, which might be the reason that Hep G2 was more sensitive than SMMC7721 cells to ARG treatment. PMID:25933104

  15. Mechanism of Arctigenin-Induced Specific Cytotoxicity against Human Hepatocellular Carcinoma Cell Lines: Hep G2 and SMMC7721.

    Directory of Open Access Journals (Sweden)

    Zheng Lu

    Full Text Available Arctigenin (ARG has been previously reported to exert high biological activities including anti-inflammatory, antiviral and anticancer. In this study, the anti-tumor mechanism of ARG towards human hepatocellular carcinoma (HCC was firstly investigated. We demonstrated that ARG could induce apoptosis in Hep G2 and SMMC7721 cells but not in normal hepatic cells, and its apoptotic effect on Hep G2 was stronger than that on SMMC7721. Furthermore, the following study showed that ARG treatment led to a loss in the mitochondrial out membrane potential, up-regulation of Bax, down-regulation of Bcl-2, a release of cytochrome c, caspase-9 and caspase-3 activation and a cleavage of poly (ADP-ribose polymerase in both Hep G2 and SMMC7721 cells, suggesting ARG-induced apoptosis was associated with the mitochondria mediated pathway. Moreover, the activation of caspase-8 and the increased expression levels of Fas/FasL and TNF-α revealed that the Fas/FasL-related pathway was also involved in this process. Additionally, ARG induced apoptosis was accompanied by a deactivation of PI3K/p-Akt pathway, an accumulation of p53 protein and an inhibition of NF-κB nuclear translocation especially in Hep G2 cells, which might be the reason that Hep G2 was more sensitive than SMMC7721 cells to ARG treatment.

  16. Structure of Sphingolipids From Sea Cucumber Cucumaria frondosa and Structure-Specific Cytotoxicity Against Human HepG2 Cells.

    Science.gov (United States)

    Jia, Zicai; Song, Yu; Tao, Suyuan; Cong, Peixu; Wang, Xiaoxu; Xue, Changhu; Xu, Jie

    2016-03-01

    To investigate the relationship between structure and activity, three glucocerebroside series (CFC-1, CFC-2 and CFC-3), ceramides (CF-Cer) and long-chain bases (CF-LCB) of sea cucumber Cucumaria frondosa (C. frondosa) were isolated and evaluated in HepG2 cells. The molecular species of CFC-1, CFC-2 and CFC-3 and CF-Cer were identified using reversed-phase liquid chromatography with heated electrospray ionization coupled to high-resolution mass spectrometry (RPLC-HESI-HRMS), and determined on the basis of chemical and spectroscopic evidence: For the three glucocerebroside series, fatty acids (FA) were mainly saturated (18:0 and 22:0), monounsaturated (22:1, 23:1 and 24:1) and 2-hydroxyl FA (2-HFA) (23:1 h and 24:1 h), the structure of long-chain bases (LCB) were dihydroxy (d17:1, d18:1 and d18:2) and trihydroxy (t16:0 and t17:0), and the glycosylation was glucose; For CF-Cer, FA were primarily saturated (17:0) and monounsaturated (16:1 and 19:1), the structure of LCB were dihydroxy (d17:1 and d18:1), and trihydroxy (t16:0). The results of cell experiment indicated that all of three glucocerebroside series, CF-Cer and CF-LCB exhibited an inhibitory effects on cell proliferation. Moreover, CFC-3 was most effective in three glucocerebrosides to HepG-2 cell viability. The inhibition effect of CF-LCB was the strongest, and the inhibition effect of CF-Cer was much stronger than glucocerebrosides. PMID:26861868

  17. PARASITE STRAIN SPECIFICITY OF PRECURSOR CYTOTOXIC T-CELLS IN INDIVIDUAL ANIMALS CORRELATES WITH CROSS-PROTECTION IN CATTLE CHALLENGED WITH THEILERIA-PARVA

    OpenAIRE

    Taracha, ELN; Goddeeris, Bruno; MORZARIA, SP; Morrison, WI

    1995-01-01

    Class I major histocompatibility complex-restricted parasite-specific cytotoxic T lymphocytes (CTL) are known to be a major component of the bovine immune response to the protozoan parasite Theileria parva, but formal proof for their role in protection of cattle against infection with T. parva has been lacking. Animals immunized with one stock of T. parva show variations in the degree of protection against heterologous challenge and also in the parasite strain specificity of their CTL respons...

  18. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Ch(a)vez-Gal(a)n L; Arenas-Del Angel MC; Zenteno E; Ch(a)vez R; Lascurain R

    2009-01-01

    One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer (NK) cells and CD8+T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor (TNF) and TNF receptor pathway. We discussed three models of possible molecular interaction between lyric molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis.

  19. Analysis of the T-cell receptor repertoire of human T-cell leukemia virus type 1 (HTLV-1) Tax-specific CD8+ cytotoxic T lymphocytes from patients with HTLV-1-associated disease: evidence for oligoclonal expansion.

    Science.gov (United States)

    Utz, U; Banks, D; Jacobson, S; Biddison, W E

    1996-02-01

    Human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic, progressive neurological disease characterized by marked degeneration of the spinal cord and the presence of antibodies against HTLV-1. Patients with HAM/TSP, but not asymptomatic carriers, show very high precursor frequencies of HTLV-1-specific CD8+ T cells in peripheral blood and cerebrospinal fluid, suggestive of a role of these T cells in the pathogenesis of the disease. In HLA-A2+ HAM/TSP patients, HTLV-1-specific T cells were demonstrated to be directed predominantly against one HTLV-1 epitope, namely, Tax11-19. In the present study, we analyzed HLA-A2-restricted HTLV-1 Tax11-19-specific cytotoxic T cells from three patients with HAM/TSP. An analysis of the T-cell receptor (TCR) repertoire of these cells revealed an absence of restricted variable (V) region usage. Different combinations of TCR V alpha and V beta genes were utilized between, but also within, the individual patients for the recognition of Tax11-19. Sequence analysis of the TCR showed evidence for an oligoclonal expansion of few founder T cells in each patient. Apparent structural motifs were identified for the CDR3 regions of the TCR beta chains. One T-cell clone could be detected within the same patient over a period of 3 years. We suggest that these in vivo clonally expanded T cells might play a role in the pathogenesis of HAM/TSP and provide information on HTLV-1-specific TCR which may elucidate the nature of the T cells that infiltrate the central nervous system in HAM/TSP patients. PMID:8551623

  20. Clonal Expansion and Cytotoxicity of TCRVβ Subfamily T Cells Induced by CML and K562 Cells

    Institute of Scientific and Technical Information of China (English)

    YupingZHang; YangqiuLi; ShaohuaChen; LijianYang; GengxinLuo; XueliZhang

    2004-01-01

    OBJECTIVE To investigate the anti-leukemia effect, the distribution and clonal expansion of TCRVβ subfamily T cells in T cells from cord blood and adult peripheral blood induced by CML cells and K562 cells in vitro. METHODS Peripheral blood T cells from one adult donor and 3 cases of cord blood were stimulated with CML cells and K562 cells and further amplified by a suspended T cell-bulk culture,in order to induce CML specific cytotoxic T lymphocytes. The induced T cells were further analyzed for the specific cytotoxicity in CML by LDH assay, the phenotype identification by indirect immunofiuorescence technique and the distribution and clonal expansion of TCRVβ subfamily by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan analysis, respectively. RESULTS Oligoclonal and oligoclonal tendency T cells with higher specific cytotoxicity from cord blood and adult peripheral blood could be induced by stimulation with CML cells and K562 cells. CONCLUSIONS Specific cytotoxic T cells for an anti-CML effect could be induced by CML cells and K562 cells .The induced T cells which have the characteristic of specific cytotoxicity against CML cells may come from the clonal expansion of TCRVβ subfamily T cells.

  1. Microchip screening platform for single cell assessment of NK cell cytotoxicity

    Directory of Open Access Journals (Sweden)

    Karolin eGuldevall

    2016-04-01

    Full Text Available Here we report a screening platform for assessment of the cytotoxic potential of individual natural killer (NK cells within larger populations. Human primary NK cells were distributed across a silicon-glass microchip containing 32 400 individual microwells loaded with target cells. Through fluorescence screening and automated image analysis the numbers of NK and live or dead target cells in each well could be assessed at different time points after initial mixing. Cytotoxicity was also studied by time-lapse live-cell imaging in microwells quantifying the killing potential of individual NK cells. Although most resting NK cells (≈75% were non-cytotoxic against the leukemia cell line K562, some NK cells were able to kill several (≥3 target cells within the 12 hours long experiment. In addition, the screening approach was adapted to increase the chance to find and evaluate serial killing NK cells. Even if the cytotoxic potential varied between donors it was evident that a small fraction of highly cytotoxic NK cells were responsible for a substantial portion of the killing. We demonstrate multiple assays where our platform can be used to enumerate and characterize cytotoxic cells, such as NK or T cells. This approach could find use in clinical applications, e.g. in the selection of donors for stem cell transplantation or generation of highly specific and cytotoxic cells for adoptive immunotherapy.

  2. Tumor specific cytotoxicity of arctigenin isolated from herbal plant Arctium lappa L.

    Science.gov (United States)

    Susanti, Siti; Iwasaki, Hironori; Itokazu, Yukiyoshi; Nago, Mariko; Taira, Naoyuki; Saitoh, Seikoh; Oku, Hirosuke

    2012-10-01

    The effectiveness of cancer chemotherapy is often limited by the toxicity to other tissues in the body. Therefore, the identification of non-toxic chemotherapeutics from herbal medicines remains to be an attractive goal to advance cancer treatments. This study evaluated the cytotoxicity profiles of 364 herbal plant extracts, using various cancer and normal cell lines. The screening found occurrence of A549 (human lung adenocarcinoma) specific cytotoxicity in nine species of herbal plants, especially in the extract of Arctium lappa L. Moreover, purification of the selective cytotoxicity in the extract of Arctium lappa L. resulted in the identification of arctigenin as tumor specific agent that showed cytotoxicity to lung cancer (A549), liver cancer (HepG2) and stomach cancer (KATO III) cells, while no cytotoxicity to several normal cell lines. Arctigenin specifically inhibited the proliferation of cancer cells, which might consequently lead to the induction of apoptosis. In conclusion, this study found that arctigenin was one of cancer specific phytochemicals, and in part responsible for the tumor selective cytotoxicity of the herbal medicine. PMID:22350142

  3. T cell retargeting with MHC class I-restricted antibodies: the CD28 costimulatory domain enhances antigen-specific cytotoxicity and cytokine production

    OpenAIRE

    Willemsen, Ralph; Ronteltap, C.; Chames, P.; Debets, Reno; Bolhuis, Reinder

    2005-01-01

    textabstractT cells require both primary and costimulatory signals for optimal activation. The primary Ag-specific signal is delivered by engagement of the TCR. The second Ag-independent costimulatory signal is mediated by engagement of the T cell surface costimulatory molecule CD28 with its target cell ligand B7. However, many tumor cells do not express these costimulatory molecules. We previously constructed phage display derived F(AB), G8, and Hyb3, Ab-based receptors with identical specif...

  4. Mycoplasma pneumoniae induces cytotoxic activity in guinea pig bronchoalveolar cells

    International Nuclear Information System (INIS)

    Precultured guinea pig alveolar macrophages (AM) and freshly harvested alveolar cells (FHAC) activated by interaction with Mycoplasma pneumoniae were cytotoxic for xenogeneic 75selenomethionine-labeled tumor target cells. Phagocytosis of whole opsonized or nonopsonized M. pneumoniae cells was more effective in eliciting cytotoxicity than uptake of sonicated microorganisms. The addition of living mycoplasma cells to the assay system enhanced the cytotoxic effect considerably. Target cells were significantly more susceptible to the cytotoxic action of phagocytes if they were coated with mycoplasma antigen or cocultured together with M. pneumoniae. The activation of the phagocytes could be inhibited by 2-deoxy-D-glucose but not by antimicrobial substances suppressing mycoplasma protein synthesis. It was accompanied by 51Cr release without detectable signs of cell damage. The supernatants of activated cells were cytotoxic for approximately 24 h. Inhibition, release, and cytotoxic activity indicate the necessity of an intact metabolism of the effector cells and suggest a secretion of cytotoxic substances

  5. Impact of polysialylated CD56 on natural killer cell cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kaltschmidt Christian

    2007-08-01

    Full Text Available Abstract Background Siglec-7, a sialic acid binding inhibitory receptor expressed by NK cells is masked in vivo by a so far unknown ligand. It shows a strong binding prevalence for α-2,8-linked disialic acids in vitro. Results Here we describe the expression of PSA-NCAM (α-2,8-linked polysialic acid modified NCAM on functional adult peripheral blood natural killer cells and examine its possible role in masking Siglec-7. Unmasking of Siglec-7 using Clostridium perfringens neuraminidase massively reduces NK cell cytotoxicity. By contrast a specific removal of PSA using Endo-NF does not lead to a reduction of NK cell cytotoxicity. Conclusion The results presented here therefore indicate that PSA-NCAM is not involved in masking Siglec-7.

  6. Nanomaterial cytotoxicity is composition, size, and cell type dependent

    Directory of Open Access Journals (Sweden)

    Sohaebuddin Syed K

    2010-08-01

    Full Text Available Abstract Background Despite intensive research efforts, reports of cellular responses to nanomaterials are often inconsistent and even contradictory. Additionally, relationships between the responding cell type and nanomaterial properties are not well understood. Using three model cell lines representing different physiological compartments and nanomaterials of different compositions and sizes, we have systematically investigated the influence of nanomaterial properties on the degrees and pathways of cytotoxicity. In this study, we selected nanomaterials of different compositions (TiO2 and SiO2 nanoparticles, and multi-wall carbon nanotubes [MWCNTs] with differing size (MWCNTs of different diameters 50 nm; but same length 0.5-2 μm to analyze the effects of composition and size on toxicity to 3T3 fibroblasts, RAW 264.7 macrophages, and telomerase-immortalized (hT bronchiolar epithelial cells. Results Following characterization of nanomaterial properties in PBS and serum containing solutions, cells were exposed to nanomaterials of differing compositions and sizes, with cytotoxicity monitored through reduction in mitochondrial activity. In addition to cytotoxicity, the cellular response to nanomaterials was characterized by quantifying generation of reactive oxygen species, lysosomal membrane destabilization and mitochondrial permeability. The effect of these responses on cellular fate - apoptosis or necrosis - was then analyzed. Nanomaterial toxicity was variable based on exposed cell type and dependent on nanomaterial composition and size. In addition, nanomaterial exposure led to cell type dependent intracellular responses resulting in unique breakdown of cellular functions for each nanomaterial: cell combination. Conclusions Nanomaterials induce cell specific responses resulting in variable toxicity and subsequent cell fate based on the type of exposed cell. Our results indicate that the composition and size of nanomaterials as well as the

  7. Human alloantigen-specific anergic cells induced by a combination of CTLA4-Ig and CsA maintain anti-leukemia and anti-viral cytotoxic responses.

    Science.gov (United States)

    Comoli, P; Locatelli, F; Moretta, A; Montagna, D; Calcaterra, V; Cometa, A; Basso, S; Zecca, M; Maccario, R

    2001-06-01

    The success of allogeneic hematopoietic stem cell transplantation from HLA-disparate donors depends on the development of new strategies for graft-versus-host disease prevention able to target specifically donor antihost alloreactivity, while preserving GVL and antiviral immune surveillance. Recent experimental and clinical work has shown the feasibility of an approach based on induction of anergy to host alloantigens through blockade of B7/CD28 costimulatory signal in donor T cells, but data on the impact of this strategy on the recovery of the immune system are still lacking. We devised an ex vivo method for induction of host alloantigen-specific unresponsiveness based on treatment with the B7/CD28 blocking agent CTLA4-Ig associated with CsA. We then proceeded to assess the maintenance of an effective immune response towards viral pathogens and tumor cells after CTLA4-Ig/CsA treatment, by measuring the frequency of CTL precursors directed against CMV- and EBV-infected targets, and against autologous leukemic blasts. We demonstrated that (1) CTLA4-Ig and CsA can act synergistically in inducing a state of unresponsiveness to alloantigens; (2) the number of leukemia-reactive, EBV-specific and CMV-specific CTLp is not impaired by CTLA4-Ig/CsA treatment. Our data provide the first direct in vitro evidence that it is possible to preserve antiviral and antileukemia effector cells after blockade of CD28/B7 interaction during MLR. PMID:11548844

  8. Dengue virus-specific cross-reactive CD8+ human cytotoxic T lymphocytes.

    OpenAIRE

    Bukowski, J F; Kurane, I; Lai, C J; Bray, M; Falgout, B; Ennis, F A

    1989-01-01

    Stimulation with live dengue virus of peripheral blood mononuclear cells from a dengue virus type 4-immune donor generated virus-specific, serotype-cross-reactive, CD8+, class I-restricted cytotoxic T lymphocytes (CTL) capable of lysing dengue virus-infected cells and cells pulsed with dengue virus antigens of all four serotypes. These CTL lysed autologous fibroblasts infected with vaccinia virus-dengue virus recombinant viruses containing the E gene or several nonstructural dengue virus type...

  9. TCR down-regulation boosts T-cell-mediated cytotoxicity and protection against poxvirus infections

    DEFF Research Database (Denmark)

    Hansen, Ann K; Regner, Matthias; Bonefeld, Charlotte M;

    2011-01-01

    Cytotoxic T (Tc) cells play a key role in the defense against virus infections. Tc cells recognize infected cells via the T-cell receptor (TCR) and subsequently kill the target cells by one or more cytotoxic mechanisms. Induction of the cytotoxic mechanisms is finely tuned by the activation signals...... from the TCR. To determine whether TCR down-regulation affects the cytotoxicity of Tc cells, we studied TCR down-regulation-deficient CD3¿LLAA mice. We found that Tc cells from CD3¿LLAA mice have reduced cytotoxicity due to a specific deficiency in exocytosis of lytic granules. To determine whether....... Finally, we found that TCR signaling in CD3¿LLAA Tc cells caused highly increased tyrosine phosphorylation and activation of the c-Cbl ubiquitin ligase, and that the impaired exocytosis of lytic granules could be rescued by the knockdown of c-Cbl. Thus, our work demonstrates that TCR down-regulation...

  10. Activation of Flucloxacillin-Specific CD8+ T-Cells With the Potential to Promote Hepatocyte Cytotoxicity in a Mouse Model.

    Science.gov (United States)

    Nattrass, Ryan; Faulkner, Lee; Vocanson, Marc; Antoine, Daniel J; Kipar, Anja; Kenna, Gerry; Nicolas, Jean-Francois; Park, B Kevin; Naisbitt, Dean J

    2015-07-01

    There are currently no animal models of drug-induced liver injury (DILI) where the adaptive immune system has been shown to damage the liver. Thus, it is difficult to explore the mechanistic basis of the tissue injury. The aim of this study was to use C57BL/6 CD4+-deficient mice with a mutation in the αβ gene encoding for Major histocompatibilty complex (MHC) class II molecules to (1) develop a mouse model of flucloxacillin sensitization, (2) explore whether drug-specific CD8+ kill primary hepatocytes, and (3) analyze perturbations in liver integrity following oral exposure to flucloxacillin. CD8+ T-cells from lymph nodes of flucloxacillin-sensitized mice were stimulated to proliferate, secrete interferon (IFN-γ) and granzyme B, and induce hepatocyte apoptosis in a concentration-dependent manner following ex vivo stimulation. The T-cell response was antigen-specific; T-cells were not activated with other β-lactam antibiotics. Furthermore, T-cell responses only occurred in the presence of flucloxacillin-pulsed antigen presenting cells. In separate experiments, flucloxacillin-specific T-cells were induced to migrate to the mesenteric lymph nodes using retinoic acid, prior to administration of oral flucloxacillin, and analysis of plasma biomarkers of liver injury. Oral exposure to flucloxacillin resulted in mild elevations in alanine aminotransferase, liver, and gall bladder leukocyte infiltration and a marked swelling of the gall bladder. Thus, CD4+-deficient mice represent a promising model to study the role of the adaptive immune system in DILI. PMID:25877613

  11. Oncolytic immunotherapy through tumor-specific translation and cytotoxicity of poliovirus.

    Science.gov (United States)

    Brown, Michael C; Gromeier, Matthias

    2015-05-01

    Achieving tumor-specific, robust, and durable effector cytotoxic immune responses is key to successful immunotherapy. This has been accomplished with adoptive cell transfer of ex vivo-expanded autologous tumor-infiltrating or engineered T cells, or with immune checkpoint inhibitors, enhancing inherent T cell reactivity. A natural ability to recruit effector responses makes tumor-targeting ('oncolytic') viruses attractive as immunotherapy vehicles. However, most viruses actively block inflammatory and immunogenic events; or, host innate immune responses may prevent immune initiating events in the first place. Moreover, the mechanisms of how virus infection can produce effector responses against host (tumor) neo-antigens are unclear. We are pioneering oncolytic immunotherapy based on poliovirus, which has no specific mechanism to interfere with host immune activation, exhibits lytic cytotoxicity in the presence of an antiviral interferon response and pre-existing immunity, and engages a powerful innate immune sensor implicated in recruiting cytotoxic T cell responses. Central to this approach is a unique confluence of factors that drive tumor-specific viral translation and cytotoxicity. PMID:26105699

  12. Cytotoxicity and Effects on Cell Viability of Nickel Nanowires

    KAUST Repository

    Rodriguez, Jose E.

    2013-05-01

    Recently, magnetic nanoparticles are finding an increased use in biomedical applications and research. Nanobeads are widely used for cell separation, biosensing and cancer therapy, among others. Due to their properties, nanowires (NWs) are gaining ground for similar applications and, as with all biomaterials, their cytotoxicity is an important factor to be considered before conducting biological studies with them. In this work, the cytotoxic effects of nickel NWs (Ni NWs) were investigated in terms of cell viability and damage to the cellular membrane. Ni NWs with an average diameter of 30-34 nm were prepared by electrodeposition in nanoporous alumina templates. The templates were obtained by a two-step anodization process with oxalic acid on an aluminum substrate. Characterization of NWs was done using X-Ray diffraction (XRD) and energy dispersive X-Ray analysis (EDAX), whereas their morphology was observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell viability studies were carried out on human colorectal carcinoma cells HCT 116 by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell proliferation colorimetric assay, whereas the lactate dehydrogenase (LDH) homogenous membrane fluorimetric assay was used to measure the degree of cell membrane rupture. The density of cell seeding was calculated to obtain a specific cell number and confluency before treatment with NWs. Optical readings of the cell-reduced MTT products were measured at 570 nm, whereas fluorescent LDH membrane leakage was recorded with an excitation wavelength of 525 nm and an emission wavelength of 580 - 640 nm. The effects of NW length, cell exposure time, as well as NW:cell ratio, were evaluated through both cytotoxic assays. The results show that cell viability due to Ni NWs is affected depending on both exposure time and NW number. On the other hand, membrane rupture and leakage was only significant at later exposure times. Both

  13. Heat Shock Proteins 60 and 70 Specific Proinflammatory and Cytotoxic Response of CD4+CD28null Cells in Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Ashok K. Yadav

    2013-01-01

    Full Text Available Background. CD4+CD28null T cells are expanded in peripheral blood of patients with chronic kidney disease and associated with subclinical atherosclerosis. However, triggers for the oligoclonal expansion and activation of these cells are not clear. Methods. We investigated twenty-five stage V-IV chronic kidney disease (CKD patients and eight healthy subjects (HC. Peripheral mononuclear cells were isolated and incubated with heat shock protein- (HSP 60 and 70. CD4+CD28null and CD4+CD28+ cells were sorted by flowcytometry and antigen specific response was assessed by the mRNA and protein expression of interferon (IFN-γ, perforin, and granzyme B using qRT-PCR and Elispot. Results. The basal mRNA expression of IFN-γ, perforin, and granzyme B in CD4+CD28null cells was higher in subjects with CKD compared to that in HC (P<0.0001. Subjects with CKD also showed expression of IFN-γ, perforin, and granzyme B in the CD4+CD28+ subset, but this was much weaker than that seen in the CD4+CD28null population (P<0.0001. We did not note the expression of these molecules at mRNA or protein level in either subset of CD4 cells in HC. After incubation with HSP60 and HSP70, CD4+CD28null cells showed increased expression at mRNA (P<0.001 and protein level (P<0.001. CD4+CD28+ cells also showed a weak increase in expression. No antigen-specific response was noted in HC. Conclusion. These data show that CD4+CD28null cells in subjects with CKD react with HSP60 and HSP70 by upregulating the expression of IFN-γ, perforin and granzyme B. Increased circulating level of HSP60 and HSP70 might play a role in initiation and/or progression of atherosclerosis in CKD subjects through perturbation of CD4+CD28null cells.

  14. Targeted cytosine deaminase-uracil phosphoribosyl transferase suicide gene therapy induces small cell lung cancer-specific cytotoxicity and tumor growth delay

    DEFF Research Database (Denmark)

    Christensen, Camilla L; Gjetting, Torben; Poulsen, Thomas Tuxen;

    2010-01-01

    Small cell lung cancer (SCLC) is a highly malignant cancer for which there is no curable treatment. Novel therapies are therefore in great demand. In the present study we investigated the therapeutic effect of transcriptionally targeted suicide gene therapy for SCLC based on the yeast cytosine...... deaminase (YCD) gene alone or fused with the yeast uracil phosphoribosyl transferase (YUPRT) gene followed by administration of 5-fluorocytosine (5-FC) prodrug. Experimental design: The YCD gene or the YCD-YUPRT gene was placed under regulation of the SCLC-specific promoter insulinoma-associated 1 (INSM1...

  15. Spontaneous cytotoxic T-Cell reactivity against indoleamine 2,3-dioxygenase-2

    DEFF Research Database (Denmark)

    Sørensen, Rikke Bæk; Køllgaard, Tania; Andersen, Rikke Sick;

    2011-01-01

    in mouse models of cancer in a nontoxic fashion. Here, we describe the immunogenicity of IDO2 by showing the presence of spontaneous cytotoxic T-cell reactivity against IDO2 in peripheral blood of both healthy donors and cancer patients. Furthermore, we show that these IDO2-specific T cells are...... cytotoxic effector cells that recognize and kill tumor cells. Our data suggest that IDO2 might be a useful target for anticancer immunotherapeutic strategies....

  16. CD85/LIR-1/ILT2 and CD152 (cytotoxic T lymphocyte antigen 4) inhibitory molecules down-regulate the cytolytic activity of human CD4+ T-cell clones specific for Mycobacterium tuberculosis.

    Science.gov (United States)

    Merlo, A; Saverino, D; Tenca, C; Grossi, C E; Bruno, S; Ciccone, E

    2001-10-01

    Antigen-specific cytolytic CD4+ T lymphocytes control Mycobacterium tuberculosis infection by secreting cytokines and by killing macrophages that have phagocytosed the pathogen. However, lysis of the latter cells promotes microbial dissemination, and other macrophages engulf the released bacteria. Subsequently, CD4+ T-cell-mediated killing of macrophages goes on, and this persistent process may hamper control of infection, unless regulatory mechanisms maintain a subtle balance between lysis of macrophages by cytolytic CD4+ cells and activation of cytolytic CD4+ cells by infected macrophages. We asked whether inhibitory molecules expressed by CD4+ cytolytic T lymphocytes could play a role in such a balance. To this end, human CD4+ T-cell clones specific for M. tuberculosis were produced that displayed an autologous major histocompatibility complex class II-restricted lytic ability against purified protein derivative (PPD)-pulsed antigen-presenting cells. All T-cell clones expressed CD152 (cytotoxic T-lymphocyte antigen 4 [CTLA-4]) and CD85/leukocyte immunoglobulin-like receptor 1 (LIR-1)/immunoglobulin-like transcript 2 (ILT2) inhibitory receptors, but not CD94 and the killer inhibitory receptor (or killer immunoglobulin-like receptor [KIR]) p58.2. CD3-mediated activation of the clones was inhibited in a redirected killing assay in which CD152 and CD85/LIR-1/ILT2 were cross-linked. Specific antigen-mediated proliferation of the clones was also sharply reduced when CD152 and CD85/LIR-1/ILT2 were cross-linked by specific monoclonal antibody (MAb) followed by goat anti-mouse antiserum. In contrast, blockade of the receptors by specific MAb only increased their proliferation. Production of interleukin 2 (IL-2) and gamma interferon (IFN-gamma) by the T-cell clones was also strongly reduced when CD152 and CD85/LIR-1/ILT2 were cross-linked. The lytic activity of the T-cell clones against PPD-pulsed autologous monocytes or Epstein-Barr virus-activated B cells was increased

  17. Natural killer cell mediated cytotoxic responses in the Tasmanian devil.

    Science.gov (United States)

    Brown, Gabriella K; Kreiss, Alexandre; Lyons, A Bruce; Woods, Gregory M

    2011-01-01

    The Tasmanian devil (Sarcophilus harrisii), the world's largest marsupial carnivore, is under threat of extinction following the emergence of an infectious cancer. Devil facial tumour disease (DFTD) is spread between Tasmanian devils during biting. The disease is consistently fatal and devils succumb without developing a protective immune response. The aim of this study was to determine if Tasmanian devils were capable of forming cytotoxic antitumour responses and develop antibodies against DFTD cells and foreign tumour cells. The two Tasmanian devils immunised with irradiated DFTD cells did not form cytotoxic or humoral responses against DFTD cells, even after multiple immunisations. However, following immunisation with xenogenic K562 cells, devils did produce cytotoxic responses and antibodies against this foreign tumour cell line. The cytotoxicity appeared to occur through the activity of natural killer (NK) cells in an antibody dependent manner. Classical NK cell responses, such as innate killing of DFTD and foreign cancer cells, were not observed. Cells with an NK-like phenotype comprised approximately 4 percent of peripheral blood mononuclear cells. The results of this study suggest that Tasmanian devils have NK cells with functional cytotoxic pathways. Although devil NK cells do not directly recognise DFTD cancer cells, the development of antibody dependent cell-mediated cytotoxicity presents a potential pathway to induce cytotoxic responses against the disease. These findings have positive implications for future DFTD vaccine research. PMID:21957452

  18. Murine cellular cytotoxicity to syngeneic and xenogeneic herpes simplex virus-infected cells.

    Science.gov (United States)

    Kohl, S; Drath, D B; Loo, L S

    1982-12-01

    Cellular cytotoxicity of C57BL/6 adult mice peritoneal cells to xenogeneic (Chang liver) and syngeneic (BL/6-WT3) herpes simplex virus (HSV)-infected cells was analyzed in a 6-h 51Cr release assay. There was no difference in antibody-dependent cellular cytotoxicity to either target. There was no natural killer cytotoxicity to targets with cells from uninfected mice except at very high effector cell ratios. HSV-infected (2 X 10(4) PFU intraperitoneally 1 day previously) mice mediated significantly higher antibody-dependent cellular cytotoxicity and required less antibody (10(-5) versus 10(-2) dilution), fewer cells, and less time to kill than cells from uninfected mice. HSV-infected mice mediated natural killer cytotoxicity but preferentially killed syngeneic HSV-infected cells. Stimulation of cytotoxicity was not virus specific since influenza-infected mice mediated similar levels of cytotoxicity to HSV-infected targets. There was no difference in morphology (95% macrophage) or in the percentage of FcR-positive cells, but infected mice had more peritoneal cells and generated higher levels of superoxide in response to opsonized zymosan or phorbolmyristate acetate. These data demonstrate nonspecific virus-stimulated metabolic and effector cell function which may enhance clearance of virus in an infected host. PMID:6295943

  19. Proteolytically modified human beta 2-microglobulin augments the specific cytotoxic activity in murine mixed lymphocyte culture

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Claësson, M H

    1987-01-01

    (M-beta 2-m) bind to murine lymphocytes expressing H-2 class I antigens; M-beta 2-m, when added at day 0 and 1 of culture in nanomolar concentrations to a one-way murine allogeneic mixed lymphocyte culture (MLC) augments the generation of specific cytotoxic T lymphocytes; M-beta 2-m increases the...... endogenous production of interleukin 2 in the MLC culture; monoclonal antibody which reacts with both the native beta 2-m and M-beta 2-m molecule blocks the augmentation of cytotoxic T lymphocyte production induced by M-beta 2-m; murine as well as human MLC responder cells can proteolytically modify native...... human beta 2-m; and the modifying activity of murine MLC responder cells was blocked in an intermediary step by an alloantibody, which reacts specifically with murine major histocompatibility complex, class I-associated beta 2-m. These findings suggest that the modification process is preceded by an...

  20. Neospora caninum-infected cattle develop parasite-specific CD4+ cytotoxic T lymphocytes.

    Science.gov (United States)

    Staska, Lauren M; McGuire, Travis C; Davies, Christopher J; Lewin, Harris A; Baszler, Timothy V

    2003-06-01

    Cattle infected with Neospora caninum readily experience transplacental parasite transmission, presumably after maternal parasitemia, leading to abortion or birth of congenitally infected calves. Cytotoxic T lymphocytes (CTL) are important mediators of protective immunity against Toxoplasma gondii, an intracellular apicomplexan protozoan closely related to N. caninum. In this study, N. caninum-specific CTL expanded from peripheral blood mononuclear cells of two major histocompatibility complex-mismatched, experimentally infected cattle were identified by using a (51)Cr release cytotoxicity assay. Enrichment and blocking of CD4(+)- and CD8(+)-T-lymphocyte effector subsets indicated that CD4(+) CTL killed N. caninum-infected, autologous target cells and that killing was mediated through a perforin/granzyme pathway. Detection and characterization of CTL responses to N. caninum in the natural, outbred, bovine host will facilitate identification of immunogens and design of immunization strategies to induce parasite-specific CTL against transplacental N. caninum transmission in cattle. PMID:12761108

  1. Photopolymerization of cell-encapsulating hydrogels: crosslinking efficiency versus cytotoxicity.

    Science.gov (United States)

    Mironi-Harpaz, Iris; Wang, Dennis Yingquan; Venkatraman, Subbu; Seliktar, Dror

    2012-05-01

    Cell-encapsulating hydrogels used in regenerative medicine are designed to undergo a rapid liquid-to-solid phase transition in the presence of cells and tissues so as to maximize crosslinking and minimize cell toxicity. Light-activated free-radical crosslinking (photopolymerization) is of particular interest in this regard because it can provide rapid reaction rates that result in uniform hydrogel properties with excellent temporal and spatial control features. Among the many initiator systems available for photopolymerization, only a few have been identified as suitable for cell-based hydrogel formation owing to their water solubility, crosslinking properties and non-toxic reaction conditions. In this study, three long-wave ultraviolet (UV) light-activtied photoinitiators (PIs) were comparatively tested in terms of cytotoxicity, crosslinking efficiency and crosslinking kinetics of cell-encapsulating hydrogels. The hydrogels were photopolymerized from poly(ethylene glycol) (PEG) diacrylate or PEG-fibrinogen precursors using Irgacure® PIs I2959, I184 and I651, as well as with a chemical initiator/accelerator (APS/TEMED). The study specifically evaluated the PI type, PI concentration and UV light intensity, and how these affected the mechanical properties of the hydrogel (i.e. maximum storage modulus), the crosslinking reaction times and the reaction's cytotoxicity to encapsulated cells. Only two initiators (I2959 and I184) were identified as being suitable for achieving both high cell viability and efficient crosslinking of the cell-encapsulating hydrogels during the photopolymerization reaction. Optimization of PI concentration or irradiation intensity was particularly important for achieving maximum mechanical properties; a sub-optimal choice of PI concentration or irradiation intensity resulted in a substantial reduction in hydrogel modulus. Cytocompatibility may be compromised by unnecessarily prolonging exposure to cytotoxic free radicals or inadvertently

  2. Cytotoxic T-lymphocyte clones, established by stimulation with the HLA-A2 binding p5365-73 wild type peptide loaded on dendritic cells In vitro, specifically recognize and lyse HLA-A2 tumour cells overexpressing the p53 protein

    DEFF Research Database (Denmark)

    Barfoed, Annette Malene; Petersen, T R; Kirkin, A F;

    2000-01-01

    recognizing p53 derived wild type (self) peptides. Furthermore, the capacity of R9V specific T cell clones to exert HLA restricted cytotoxicity, argues that the R9V peptide is naturally presented on certain cancer cells. This supports the view that p53 derived wild type peptides might serve as candidate......Mutations in the tumour suppressor gene p53 are among the most frequent genetic alterations in human malignancies, often associated with an accumulation of the p53 protein in the cytoplasm. We have generated a number of cytotoxic T lymphocyte (CTL) clones that specifically recognize the HLA-A*0201...... p53 wild type peptide RMPEAAPPV [65-73], designated R9V, by the in vitro stimulation of CD8 enriched peripheral blood lymphocytes from a healthy HLA-A*0201 donor using peptide loaded autologous dendritic cells. A total of 22 CTL clones were generated from the same bulk culture and demonstrated to...

  3. Mitochondrial electron transport chain identified as a novel molecular target of SPIO nanoparticles mediated cancer-specific cytotoxicity.

    Science.gov (United States)

    He, Chengyong; Jiang, Shengwei; Jin, Haijing; Chen, Shuzhen; Lin, Gan; Yao, Huan; Wang, Xiaoyong; Mi, Peng; Ji, Zhiliang; Lin, Yuchun; Lin, Zhongning; Liu, Gang

    2016-03-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) are highly cytotoxic and target cancer cells with high specificity; however, the mechanism by which SPIONs induce cancer cell-specific cytotoxicity remains unclear. Herein, the molecular mechanism of SPION-induced cancer cell-specific cytotoxicity to cancer cells is clarified through DNA microarray and bioinformatics analyses. SPIONs can interference with the mitochondrial electron transport chain (METC) in cancer cells, which further affects the production of ATP, mitochondrial membrane potential, and microdistribution of calcium, and induces cell apoptosis. Additionally, SPIONs induce the formation of reactive oxygen species in mitochondria; these reactive oxygen species trigger cancer-specific cytotoxicity due to the lower antioxidative capacity of cancer cells. Moreover, the DNA microarray and gene ontology analyses revealed that SPIONs elevate the expression of metallothioneins in both normal and cancer cells but decrease the expression of METC genes in cancer cells. Overall, these results suggest that SPIONs induce cancer cell death by targeting the METC, which is helpful for designing anti-cancer nanotheranostics and evaluating the safety of future nanomedicines. PMID:26773667

  4. A new class of pluripotent stem cell cytotoxic small molecules.

    Directory of Open Access Journals (Sweden)

    Mark Richards

    Full Text Available A major concern in Pluripotent Stem Cell (PSC-derived cell replacement therapy is the risk of teratoma formation from contaminating undifferentiated cells. Removal of undifferentiated cells from differentiated cultures is an essential step before PSC-based cell therapies can be safely deployed in a clinical setting. We report a group of novel small molecules that are cytotoxic to PSCs. Our data indicates that these molecules are specific and potent in their activity allowing rapid eradication of undifferentiated cells. Experiments utilizing mixed PSC and primary human neuronal and cardiomyocyte cultures demonstrate that up to a 6-fold enrichment for specialized cells can be obtained without adversely affecting cell viability and function. Several structural variants were synthesized to identify key functional groups and to improve specificity and efficacy. Comparative microarray analysis and ensuing RNA knockdown studies revealed involvement of the PERK/ATF4/DDIT3 ER stress pathway. Surprisingly, cell death following ER stress induction was associated with a concomitant decrease in endogenous ROS levels in PSCs. Undifferentiated cells treated with these molecules preceding transplantation fail to form teratomas in SCID mice. Furthermore, these molecules remain non-toxic and non-teratogenic to zebrafish embryos suggesting that they may be safely used in vivo.

  5. Helper cell-independent cytotoxic clones in man

    OpenAIRE

    1982-01-01

    We report here a class of helper cell-independent cytotoxic T cell (HITc) clones in man that can proliferate in response to antigenic stimulation as well as mediate cytotoxicity. HITc appear to be rare among clones derived from primary in vitro allosensitized culture, but constitute the majority of clones derived from cells sensitized to autologous Epstein-Barr virus-transformed lymphoblastoid cell lines. The implications of the derivation and function of HITc clones are discussed.

  6. Serglycin determines secretory granule repertoire and regulates natural killer cell and cytotoxic T lymphocyte cytotoxicity.

    Science.gov (United States)

    Sutton, Vivien R; Brennan, Amelia J; Ellis, Sarah; Danne, Jill; Thia, Kevin; Jenkins, Misty R; Voskoboinik, Ilia; Pejler, Gunnar; Johnstone, Ricky W; Andrews, Daniel M; Trapani, Joseph A

    2016-03-01

    The anionic proteoglycan serglycin is a major constituent of secretory granules in cytotoxic T lymphocyte (CTL)/natural killer (NK) cells, and is proposed to promote the safe storage of the mostly cationic granule toxins, granzymes and perforin. Despite the extensive defects of mast cell function reported in serglycin gene-disrupted mice, no comprehensive study of physiologically relevant CTL/NK cell populations has been reported. We show that the cytotoxicity of serglycin-deficient CTL and NK cells is severely compromised but can be partly compensated in both cell types when they become activated. Reduced intracellular granzyme B levels were noted, particularly in CD27(+) CD11b(+) mature NK cells, whereas serglycin(-/-) TCR-transgenic (OTI) CD8 T cells also had reduced perforin stores. Culture supernatants from serglycin(-/-) OTI T cells and interleukin-2-activated NK contained increased granzyme B, linking reduced storage with heightened export. By contrast, granzyme A was not significantly reduced in cells lacking serglycin, indicating differentially regulated trafficking and/or storage for the two granzymes. A quantitative analysis of different granule classes by transmission electronmicroscopy showed a selective loss of dense-core granules in serglycin(-/-) CD8(+) CTLs, although other granule types were maintained quantitatively. The findings of the present study show that serglycin plays a critical role in the maturation of dense-core cytotoxic granules in cytotoxic lymphocytes and the trafficking and storage of perforin and granzyme B, whereas granzyme A is unaffected. The skewed retention of cytotoxic effector molecules markedly reduces CTL/NK cell cytotoxicity, although this is partly compensated for as a result of activating the cells by physiological means. PMID:26756195

  7. Ultrastructural studies of time-course and cellular specificity of interleukin-1 mediated islet cytotoxicity

    DEFF Research Database (Denmark)

    Mandrup-Poulsen, T; Egeberg, J; Nerup, J; Bendtzen, K; Dinarello, C A; Nielsen, Jens Høiriis

    1987-01-01

    Previous electron-microscopic studies of isolated islets of Langerhans exposed to the monokine interleukin-1 for 7 days have indicated that interleukin-1 is cytotoxic to all islet cells. To study the time-course and possible cellular specificity of interleukin-1 cytotoxicity to islets exposed to...... interleukin-1 for short time periods, isolated rat or human islets were incubated with or without 25 U/ml highly purified human interleukin-1 for 24 h. Samples of rat islets were taken after 5 min, 30 min, 1, 2, 4, 6, 8, 10, 12, 16, 20 and 24 h and samples of human islets after 5 min, 30 min and 24 h of...... incubation and examined by electron microscopy in a blinded fashion. Already after 30 min, accumulation of opaque intracytoplasmic bodies without apparent surrounding membranes, and autophagic vacuoles were seen in about 20% of the beta cells examined in rat islets exposed to interleukin-1. After 16 h of...

  8. Cytotoxicity of proparacaine to human corneal endothelial cells in vitro.

    Science.gov (United States)

    Wen, Qian; Fan, Tingjun; Bai, Suran; Sui, Yunlong

    2015-08-01

    Proparacaine is a widely used topical anesthetic in ophthalmic optometry and surgery, and has been reported to have cytotoxic effects on rabbit corneal endothelial cells after prolonged and repeated usage. Since rabbit is an exceptive mammal whose corneal endothelial cells still maintaining proliferation abilities even in adulthood, whether proparacaine has cytotoxic effects on human corneal endothelial (HCE) cells need to be further verified. Our objectives in the present study were to investigate the cytotoxicity to HCE cells of proparacaine and its underlying mechanisms in vitro and verify the cytotoxicity using cat corneal endothelial (CCE) cells in an in vivo model of cat corneas. Cytotoxic evaluation results indicated that a dose- and time-dependent toxic response of HCE cells to proparacaine over 0.03125% was rated based on morphology and viability, and a toxic response of CCE cells to 0.5% (clinical applied dosage) proparacaine was also rated based on cell density and histology. Importantly, treatment with proparacaine resulted in significant elevation of plasma membrane permeability, cell cycle arrest at S phase, fragmentation of genomic DNA, formation of apoptotic bodies, and externalization of phosphatidylserine (PS) of HCE cells. Moreover, proparacaine demonstrated disrupting effects on mitochondrial transmembrane potential (MTP) of HCE cells and activating effects on caspase-3, -8 and -9. This study demonstrates that proparacaine has notable cytotoxicity to both HCE cells in vitro and CCE cells in vivo, and its dose- and time-dependent cytotoxicity to HCE cells is achieved by inducing apoptosis via a mitochondrion-mediated caspase-dependent pathway. These findings provide new insights into the cytotoxicity and apoptosis-inducing effect of local anesthetics which should be used with great caution in the eye clinic. PMID:26165639

  9. Targeted cytosine deaminase-uracil phosphoribosyl transferase suicide gene therapy induces small cell lung cancer-specific cytotoxicity and tumor growth delay

    DEFF Research Database (Denmark)

    Christensen, Camilla L; Gjetting, Torben; Poulsen, Thomas Tuxen;

    2010-01-01

    deaminase (YCD) gene alone or fused with the yeast uracil phosphoribosyl transferase (YUPRT) gene followed by administration of 5-fluorocytosine (5-FC) prodrug. Experimental design: The YCD gene or the YCD-YUPRT gene was placed under regulation of the SCLC-specific promoter insulinoma-associated 1 (INSM1...

  10. Comparison of mammalian and fish cell line cytotoxicity: impact of endpoint and exposure duration

    International Nuclear Information System (INIS)

    Comparisons of acute toxic concentrations of chemicals to fish in vivo and cytotoxic concentrations to fish cell lines in vitro reveal rather good correlations of the toxic potencies in vitro and in vivo, but a clearly lower sensitivity of the fish cells. To examine whether the low sensitivity is specific for fish cells, cytotoxic potencies of reference chemicals from the Multicenter Evaluation of In Vitro Cytotoxicity program (MEIC) reported for the fish cell lines R1 and RTG-2 were compared with those obtained with the mouse Balb/c 3T3 cell line. Cytotoxic potencies (EC50 values) for MEIC reference chemicals were determined with exponentially growing Balb/c 3T3 cells using three different test protocols. To assess both endpoints, cell proliferation and cell survival, EC50 values were measured for the decrease in final cell protein after 24 and 72 h of exposure and for the reduction of cell protein increase during 24 h of exposure. EC50 values obtained with the fish cell lines R1 and RTG-2 using cell survival as endpoint were taken from the MEIC data base. The comparison of cytotoxic potencies shows that, in general, the fish cell lines and the mammalian cell line are almost equally sensitive towards the cytotoxic action of chemicals. The mammalian cell line assay, however, becomes considerably more sensitive, by factors of 3.4-8.5, than the fish cell line assays, if cell growth instead of cell survival is used as endpoint. It is concluded, that cell proliferation might be a better endpoint than cell survival and that mammalian cell lines might be suited to assess fish acute toxicity

  11. Propranolol sensitizes thyroid cancer cells to cytotoxic effect of vemurafenib.

    Science.gov (United States)

    Wei, Wei-Jun; Shen, Chen-Tian; Song, Hong-Jun; Qiu, Zhong-Ling; Luo, Quan-Yong

    2016-09-01

    Treatment options for advanced metastatic or progressive thyroid cancers are limited. Although targeted therapy specifically inhibiting intracellular kinase signaling pathways has markedly changed the therapeutic landscape, side-effects and resistance of single agent targeted therapy often leads to termination of the treatment. The objective of the present study was to identify the antitumor property of the non-selective β-adrenergic receptor antagonist propranolol for thyroid cancers. Human thyroid cancer cell lines 8505C, K1, BCPAP and BHP27 were used in the present study. Broad β-blocker propranolol and β2-specific antagonist ICI118551, but not β1-specific antagonist atenolol, inhibited the growth of 8505C and K1 cells. Propranolol treatment inhibited growth and induced apoptosis of 8505C cells in vitro and in vivo, which are closely associated with decreased expressions of cyclin D1 and anti-apoptotic Bcl-2. Expression of hexokinase 2 (HK2) and glucose transporter 1 (GLUT1) also decreased following propranolol intervention. 18F-FDG PET/CT imaging of the 8505C xenografts validated shrinkage of the tumors in the propranolol-treated group when compared to the phosphate‑buffered saline treated group. Finally, we found that propranolol can amplify the cytotoxicity of vemurafenib and sensitize thyroid cancer cells to cytotoxic effect of vemurafenib. Our present results suggest that propranolol has potential activity against thyroid cancers and investigation of the combination with targeted molecular therapy for progressive thyroid cancers could be beneficial. PMID:27432558

  12. Reduced LAK cytotoxicity of peripheral blood mononuclear cells in patients with bladder cancer

    DEFF Research Database (Denmark)

    Hermann, G G; Petersen, K R; Steven, K; Zeuthen, J

    1990-01-01

    determined in healthy controls. The differences in the cytotoxicities were correlated with specific changes in the subsets of peripheral blood mononuclear cells (PBMC). PBMC from 37 patients and 13 healthy controls were tested against the bladder cancer cell line T24 in 51Cr-release assays. The PBMC subsets......The cytotoxicity of unstimulated peripheral blood mononuclear cells (US-PBMC), phytohemagglutinin (PHA)-stimulated PBMC (PS-PBMC) and interleukin-2 (IL-2)-activated PBMC (LAK cells) was assessed in patients with noninvasive and invasive transitional-cell bladder cancer and compared with those...... the reduced ability of bladder cancer patient PBMC to develop LAK-cell cytotoxicity is a result of a low incidence of CD56+ and CD57+ cells in the blood. These findings indicate that IL-2 therapy alone might not be a sufficient therapy of bladder cancer patients....

  13. Inefficient boosting of antitumor CD8+ T cells by dendritic-cell vaccines is rescued by restricting T-cell cytotoxic functions

    OpenAIRE

    Zhi-Iong Ma, Joel; Yang, Jianping; Qin, Jim S.; Richter, Antonia; PERRET, Rachel; El-Deiry, Wafik S.; Finnberg, Niklas; Ronchese, Franca

    2012-01-01

    Dendritic cells (DCs) are powerful activators of primary and secondary immune responses and have promising activity as anticancer vaccines. However, various populations of immune cells, including natural killer cells, regulatory T cells and especially cytotoxic T lymphocytes (CTLs), can inhibit DC function through cytotoxic clearance. Spontaneous tumor-specific CTL responses are frequently observed in patients before immunotherapy, and it is unclear how such pre-existing responses may affect ...

  14. Regulation of IL-2 induced proliferation and cytotoxicity in human natural killer cells by monoclonal antibodies

    International Nuclear Information System (INIS)

    Natural killer (NK) activity is mediated by a subpopulation of cells termed large granular lymphocytes (LGL), which exhibit cytotoxic activity against a variety of tumor targets. LGL express OKT8, OKT9, OKT10, OKT11, 3G8 (FcγR), OKM1, NKH1. The addition of recombinant IL-2 (rIL-2), increases cytotoxicity, induces IFN-γ production and leads to LGL proliferation. Since monoclonal antibodies (MoAb) represent highly specific probes to analyze possible surface molecules, they have studied the role of various MoAbs in the regulation of cytotoxicity, proliferation, and secretory function of purified LGL. LGL were isolated from nonadherent human peripheral blood leukocytes on discontinuous Percoll density gradients, followed by 290C E-rosette depletion of contaminating T cells. These preparations were ≥ 85% LGL and contained ≥ 5% OKT3+ cells. Using a limiting dilution assay, purified LGL were incubated with rIL-2 and the MoAbs (10 μg/ml) for 7 days. These cells were tested for cytotoxicity against K562 in a 51Cr- release assay, and for proliferation as determined by 3H-thymidine incorporation. Results indicate that the OKT9 antibody inhibited both the cytotoxicity and proliferation. MoAb against LGl markers (OKT11, OKT8, OKM1, 3G8, and NKH1) had no effect on cytotoxicity or proliferation. Unlike the T cell receptor complex (with OKT3), the surface molecules examined do not regulate LGL lysis or proliferation

  15. Antigen processing influences HIV-specific cytotoxic T lymphocyte immunodominance

    DEFF Research Database (Denmark)

    Tenzer, Stefan; Wee, Edmund; Burgevin, Anne;

    2009-01-01

    Although cytotoxic T lymphocytes (CTLs) in people infected with human immunodeficiency virus type 1 can potentially target multiple virus epitopes, the same few are recognized repeatedly. We show here that CTL immunodominance in regions of the human immunodeficiency virus type 1 group-associated ......Although cytotoxic T lymphocytes (CTLs) in people infected with human immunodeficiency virus type 1 can potentially target multiple virus epitopes, the same few are recognized repeatedly. We show here that CTL immunodominance in regions of the human immunodeficiency virus type 1 group...

  16. Extracellular thiol-assisted selenium uptake dependent on the x(c)(-) cystine transporter explains the cancer-specific cytotoxicity of selenite

    DEFF Research Database (Denmark)

    Olm, E.; Fernandes, A. P.; Hebert, C.;

    2009-01-01

    The selenium salt selenite (SeO32-) is cytotoxic in low to moderate concentrations, with a remarkable specificity for cancer cells resistant to conventional chemotherapy. Our data show that selenium uptake and accumulation, rather than intracellular events, are crucial to the specific selenite...... cytotoxicity observed in resistant cancer cells. We show that selenium uptake depends on extracellular reduction, and that the extracellular environment is a key factor specific to selenite cytotoxicity. The extracellular reduction is mediated by cysteine, and the efficacy is determined by the uptake...

  17. Differentiation of cytotoxicity using target cells labelled with europium and samarium by electroporation.

    Science.gov (United States)

    Bohlen, H; Manzke, O; Engert, A; Hertel, M; Hippler-Altenburg, R; Diehl, V; Tesch, H

    1994-07-12

    We report the simultaneous use of europium-DTPA (Eu-DTPA) and samarium-DTPA (Sm-DTPA) in cytotoxicity experiments to analyze simultaneously LAK and NK cell lysis and to differentiate between specific target lysis and bystander killing. The target cells were either labelled with Eu-DTPA or Sm-DTPA chelates by electroporation, which permits the use of target cell lines or primary leukemic B cells (B-CLL) that cannot be labelled by the conventional dextran-sulphate method. The release of europium and samarium reaches a maximum at comparable time intervals (2-3 h). Due to the shorter counting interval within the samarium window the labelling efficiency is about ten times less efficient compared to europium. Using europium as label for the LAK target Daudi and samarium as label for the NK sensitive cell line K562 the differentiation of LAK versus NK activity can be performed in a single culture assay. Also, the killing of B cells and bystander cells by cytotoxic T cells was analyzed in a system where T cells were redirected to B cells through CD3 x CD19 bispecific antibodies. In fact, no bystander killing was noted when bispecific antibodies were used to bridge cytotoxic T cells to the B cells. This approach provides a simple non-radioactive method for evaluating cytotoxicity against two different cells in a single culture well. PMID:8034986

  18. Cytotoxic studies of paclitaxel (Taxol) in human tumour cell lines.

    OpenAIRE

    Liebmann, J. E.; Cook, J. A.; Lipschultz, C.; Teague, D.; Fisher, J; Mitchell, J B

    1993-01-01

    The cytotoxicity of paclitaxel against eight human tumour cell lines has been studied with in vitro clonogenic assays. The fraction of surviving cells fell sharply after exposure for 24 h to paclitaxel concentrations ranging from 2 to 20 nM; the paclitaxel IC50 was found to range between 2.5 and 7.5 nM. Increasing the paclitaxel concentration above 50 nM, however, resulted in no additional cytotoxicity after a 24 h drug exposure. Cells incubated in very high concentrations of paclitaxel (10,0...

  19. Melatonin Cytotoxicity Is Associated to Warburg Effect Inhibition in Ewing Sarcoma Cells

    Science.gov (United States)

    Sanchez-Sanchez, Ana M.; Antolin, Isaac; Puente-Moncada, Noelia; Suarez, Santos; Gomez-Lobo, Marina; Rodriguez, Carmen; Martin, Vanesa

    2015-01-01

    Melatonin kills or inhibits the proliferation of different cancer cell types, and this is associated with an increase or a decrease in reactive oxygen species, respectively. Intracellular oxidants originate mainly from oxidative metabolism, and cancer cells frequently show alterations in this metabolic pathway, such as the Warburg effect (aerobic glycolysis). Thus, we hypothesized that melatonin could also regulate differentially oxidative metabolism in cells where it is cytotoxic (Ewing sarcoma cells) and in cells where it inhibits proliferation (chondrosarcoma cells). Ewing sarcoma cells but not chondrosarcoma cells showed a metabolic profile consistent with aerobic glycolysis, i.e. increased glucose uptake, LDH activity, lactate production and HIF-1α activation. Melatonin reversed Ewing sarcoma metabolic profile and this effect was associated with its cytotoxicity. The differential regulation of metabolism by melatonin could explain why the hormone is harmless for a wide spectrum of normal and only a few tumoral cells, while it kills specific tumor cell types. PMID:26252771

  20. Cytotoxicity study of rock wool by cell magnetometric evaluation.

    Science.gov (United States)

    Kudo, Yuichiro; Kotani, Makoto; Aizawa, Yoshiharu

    2009-11-01

    The cytotoxicity of rock wool (RW), an asbestos substitute, was evaluated by cell magnetometry. Alveolar macrophages were isolated from male Fisher rats. Following addition of triiron tetraoxide (Fe(3)O(4)) to macrophages, RW was added. Then, the remnant magnetic field strength was measured for 20min after magnetization by an external field. Relaxation, an indicator of decay of cytotoxicity, was observed by cell magnetometry immediately postmagnetization in the group to which RW was added. In general, materials phagocytosed by macrophages are ingested into phagosomes and digested while migrating. This migration of phagosomes occurs by polymerization and depolymerization of the cytoskeleton. As a result of evaluation, relaxation was not delayed by addition of RW, since RW caused no effect on the cytoskeleton. It was suggested that RW has no cytotoxicity as evaluated by cell magnetometry. PMID:19559064

  1. Cytotoxicity of the saponin TTB2 on Ewing sarcoma cells

    OpenAIRE

    Huang, Wenfeng; Zou, Kun

    2015-01-01

    The steroidal saponin TTB2 can be isolated from the n-BuOH extracts of Trillium tschonoskii Maxim. The aim of the present study was to observe whether this saponin exerted any cytotoxic effects on malignant sarcoma cells, and to further investigate the possible underlying molecular mechanisms. The cell viability, cell cycle arrest and phosphorylation of certain important signal molecules in the sarcoma cell line were investigated. It was found that TTB2 inhibited the growth of the Ewing sarco...

  2. Analysis of Gag-specific Cytotoxic T Lymphocytes in Simian Immunodeficiency Virus–infected Rhesus Monkeys by Cell Staining with a Tetrameric Major Histocompatibility Complex Class I–Peptide Complex

    OpenAIRE

    Kuroda, Marcelo J.; Schmitz, Jörn E.; Barouch, Dan H.; Craiu, Abie; Allen, Todd M.; Sette, Alessandro; Watkins, David I.; Forman, Meryl A.; Letvin, Norman L.

    1998-01-01

    A tetrameric recombinant major histocompatibility complex (MHC) class I–peptide complex was used as a staining reagent in flow cytometric analyses to quantitate and define the phenotype of Gag-specific cytotoxic T lymphocytes (CTLs) in the peripheral blood of simian immunodeficiency virus macaque (SIVmac)-infected rhesus monkeys. The heavy chain of the rhesus monkey MHC class I molecule Mamu-A*01 and β2-microglobulin were refolded in the presence of an SIVmac Gag synthetic peptide (p11C, C–M)...

  3. Novel Lipid-Soluble Thiol-Redox Antioxidant and Heavy Metal Chelator, N,N′-bis(2-Mercaptoethyl)Isophthalamide (NBMI) and Phospholipase D-Specific Inhibitor, 5-Fluoro-2-Indolyl Des-Chlorohalopemide (FIPI) Attenuate Mercury-Induced Lipid Signaling Leading to Protection Against Cytotoxicity in Aortic Endothelial Cells

    OpenAIRE

    Secor, Jordan D.; Kotha, Sainath R.; Gurney, Travis O.; Patel, Rishi B.; Kefauver, Nicholas R.; Gupta, Niladri; Morris, Andrew J.; Haley, Boyd E.; Parinandi, Narasimham L.

    2011-01-01

    Here, we investigated thiol-redox-mediated phospholipase D (PLD) signaling as a mechanism of mercury cytotoxicity in mouse aortic endothelial cell (MAEC) in vitro model utilizing the novel lipid-soluble thiol-redox antioxidant and heavy metal chelator, N,N′-bis(2-mercaptoethyl)isophthalamide (NBMI) and the novel PLD-specific inhibitor, 5-fluoro-2-indolyl des-chlorohalopemide (FIPI). Our results demonstrated (i) mercury in the form of mercury(II) chloride, methylmercury, and thimerosal induced...

  4. Cytotoxicity of polycyclic nitroaromatic hydrocarbons to rat tracheal epithelial cells

    International Nuclear Information System (INIS)

    Four nitropolycyclic aromatic hydrocarbons (HPAH) were investigated for their cytotoxic effects on rat tracheal epithelial (RTE) cells. 6-Nitrochrysene (6-NC), 1,6-dinitropyrene (1,6-DNP), 1-nitropyrene (1-NP), and 4-nitropyrene (4-NP) induced dose dependent decreases in the relative colony-forming efficiency (RCFE) of RTE cells. The compounds could be separated into two groups based on the magnitude of their cytotoxic effects, a highly cytotoxic group (6-NC and 1,6-DNP), and a group with low cytotoxicity (1-NP nd 4-NP). The most cytotoxic compound was 6-NC, with an ED50 of 0.13 μM, followed by 1,6-DNP, 4-NP, and 1-NP with ED50s of 1.24 μM, 8.9 μM, and 9.1 μM, respectively. These studies show that RTE cells have the metabolic capacity to activate NAPH to toxic metabolites and should be very useful for evaluating the potential toxic effects of this ubiquitous class of airborne pollutants. (author)

  5. Cytotoxicity Effects of Amoora rohituka and chittagonga on Breast and Pancreatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Leo L. Chan

    2011-01-01

    Full Text Available Chemotherapeutic agents for cancer are highly toxic to healthy tissues and hence alternative medicine avenues are widely researched. Majority of the recent studies on alternative medicine suggested that Amoora rohituka possesses considerable antitumor and antibacterial properties. In this work, rohituka and chittagonga, fractionated with petroleum ether, dichloromethane, and ethanol, were explored for their anticancer potential against two breast cancer (MCF-7 and HTB-126 and three pancreatic cancer (Panc-1, Mia-Paca2, and Capan1. The human foreskin fibroblast, Hs68, was also included. Cytotoxicity of each extract was analyzed using the MTT assay and label-free photonic crystal biosensor assay. A concentration series of each extract was performed on the six cell lines. For MCF-7 cancer cells, the chittagonga (Pet-Ether and CH2Cl2 and rohituka (Pet-Ether extracts induced cytotoxicity; the chittagonga (EtoAC and rohituka (MeOH extracts did not induce cytotoxicity. For HTB126, Panc-1, Mia-Paca2, and Capan-1 cancer cells, only the chittagonga CH2Cl2 extract showed a significant cytotoxic effect. The extracts were not cytotoxic to normal fibroblast Hs68 cells, which may be correlated to the specificity of Amoora extracts in targeting cancerous cells. Based on these results, further examination of the potential anticancer properties Amoora species and the identification of the active ingredients of these extracts is warranted.

  6. Cell cooperation in coelomocyte cytotoxic activity of Paracentrotus lividus coelomocytes.

    Science.gov (United States)

    Arizza, Vincenzo; Giaramita, Francesca Tiziana; Parrinello, Daniela; Cammarata, Matteo; Parrinello, Nicolò

    2007-06-01

    The coelomic fluid from the sea urchin Paracentrotus lividus contains several coelomocyte types including amoebocytes and uncoloured spherulocytes involved in immune defences. In the present paper, we show a Ca(2+)-dependent cytotoxic activity for the unfractionated coelomocytes assayed in vitro, with rabbit erythrocytes and the K562 tumour cell line. In a plaque-forming assay, whole coelomocyte preparations as well as density gradient separated coelomocyte populations revealed that cell populations enriched in uncoloured spherulocytes, exerted high cytotoxic activity by releasing lysins in the presence of amoebocytes. This cooperative effect could be dependent on soluble factors released by amoebocytes. With regard to this, we show that an enhanced cytotoxic activity was found by adding the supernatant from sonicated amoebocytes or hemocyte culture medium into spherulocyte preparations. PMID:17329136

  7. Evaluation of cell cytotoxic effect on herbal extracts mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Gwon, Hui Jeong; Choi, Bo Ram; Lim, Youn Mook; Nho, Young Chang [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2009-12-15

    Herbal extracts (HE) such as Houttuynia cordata Thunb., Eucommia ulimoides, Plantago asiatica var., Morus alba L., and Ulmus davidiana var., are known to suppress an atopic dermatitis like skin lesions. In this study, to evaluate the cell cytotoxicity effect on L929, HaCaT and HMC-1 cell by the HE, the herbs were extracted with distilled water (at 75 .deg. C) and then the HE mixtures were freeze-dried for 5 days and sterilized with {gamma}-rays. The cytotoxicity was measured by Cell Counting Kit-8 (CCK-8) assay. The result showed that the HE mixtures did not significantly affect cell viability and had no toxicity on the cells. These findings indicate that the HE mixtures can be used as a potential therapeutic agent.

  8. Poly (D,L-lactide-co-glycolide nanoparticles: Uptake by epithelial cells and cytotoxicity

    Directory of Open Access Journals (Sweden)

    J. H. Hamman

    2014-03-01

    Full Text Available Nanoparticles as drug delivery systems offer benefits such as protection of the encapsulated drug against degradation, site-specific targeting and prolonged blood circulation times. The aim of this study was to investigate nanoparticle uptake into Caco-2 cell monolayers, their co-localization within the lysosomal compartment and their cytotoxicity in different cell lines. Rhodamine-6G labelled poly(D,L-lactide-co-glycolide (PLGA nanoparticles were prepared by a double emulsion solvent evaporation freeze-drying method. Uptake and co-localisation of PLGA nanoparticles in lysosomes were visualized by confocal laser scanning microscopy. The cytotoxicity of the nanoparticles was evaluated on different mammalian cells lines by means of Trypan blue exclusion and the MTS assay. The PLGA nanoparticles accumulated in the intercellular spaces of Caco-2 cell monolayers, but were also taken up transcellularly into the Caco-2 cells and partially co-localized within the lysosomal compartment indicating involvement of endocytosis during uptake. PLGA nanoparticles did not show cytotoxic effects in all three cell lines. Intact PLGA nanoparticles are therefore capable of moving across epithelial cell membranes partly by means of endocytosis without causing cytotoxic effects.

  9. CuO nanoparticles induce cytotoxicity and apoptosis in human K562 cancer cell line via mitochondrial pathway, through reactive oxygen species and P53

    OpenAIRE

    Maryam Shafagh; Fatemeh Rahmani; Norouz Delirezh

    2015-01-01

    Objective(s): This study focused on determining cytotoxic effects of copper oxide nanoparticles (CuO NPs) on chronic myeloid leukemia (CML) K562 cell line in a cell-specific manner and its possible mechanism of cell death. We investigated the cytotoxicity of CuO NPs against K562 cell line (cancerous cell) and peripheral blood mononuclear cell (normal cell). Materials and Methods: The toxicity was evaluated using cell viability, oxidative stress and apoptosis detection. In addition, the expres...

  10. Cambogin is preferentially cytotoxic to cells expressing PDGFR.

    Directory of Open Access Journals (Sweden)

    Ze Tian

    Full Text Available Platelet-derived growth factor receptors (PDGFRs have been implicated in a wide array of human malignancies, including medulloblastoma (MB, the most common brain tumor of childhood. Although significant progress in MB biology and therapeutics has been achieved during the past decades, MB remains a horrible challenge to the physicians and researchers. Therefore, novel inhibitors targeting PDGFR signaling pathway may offer great promise for the treatment of MB. In the present study, we investigated the cytotoxicity and mechanisms of cambogin in Daoy MB cells. Our results show that cambogin triggers significant S phase cell cycle arrest and apoptosis via down regulation of cyclin A and E, and activation of caspases. More importantly, further mechanistic studies demonstrated that cambogin inhibits PDGFR signaling in Daoy and genetically defined mouse embryo fibroblast (MEF cell lines. These results suggest that cambogin is preferentially cytotoxic to cells expressing PDGFR. Our findings may provide a novel approach by targeting PDGFR signaling against MB.

  11. Construction of HA-1-DC Nucleic-acid Vaccine and Induction of Specific Cytotoxic T Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    WANG Yaya; ZHANG Donghua; HU Jinmei; LIU Wenli; ZHOU hongsheng; ZHANG Lu; LIU Dan; HUANG Zhenqian; TAN Huo

    2007-01-01

    An HA-1-DC nucleic-acid vaccine was constructed to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). DCs were generated from HSCT donors in vitro, and its immunologic activity was assayed by using flow cytometry and mixed lymphocytes reaction.HA-1 gene was electroporated into the cultured DCs to construct a DC nucleic-acid vaccine. After transfection for 48 h, the expression of HA-1 protein could be detected by using Western blot. The DCs were cultured with syngenic lymphocytes to induce specific cytotoxic T lymphocytes (CTLs).The cytoxicity of the CTLs was detected by LDH assay. The results showed that The DCs derived from peripheral blood monocytes (PBMCs) expressed the phenotype of DCs, and were effective in stimulating proliferation of the allogenic lymphocytes. After electroporating for 48-h, HA-1 protein was detected by using Western blot. The cytotoxity of inducing CTLs was higher than the control group. It was suggested that minor histocompatibility antigen HA-1 could be considered as a target of immunotherapy against leukemia after HSCT.

  12. Phototoxicity and cytotoxicity of fullerol in human lens epithelial cells

    International Nuclear Information System (INIS)

    The water-soluble, hydroxylated fullerene [fullerol, nano-C60(OH)22-26] has several clinical applications including use as a drug carrier to bypass the blood ocular barriers. We have assessed fullerol's potential ocular toxicity by measuring its cytotoxicity and phototoxicity induced by UVA and visible light in vitro with human lens epithelial cells (HLE B-3). Accumulation of nano-C60(OH)22-26 in the cells was confirmed spectrophotometrically at 405 nm and cell viability estimated using MTS and LDH assays. Fullerol was cytotoxic to HLE B-3 cells maintained in the dark at concentrations higher than 20 μM. Exposure to either UVA or visible light in the presence of > 5 μM fullerol-induced phototoxic damage. When cells were pretreated with non-toxic antioxidants: 20 μM lutein, 1 mM N-acetyl cysteine, or 1 mM L-ascorbic acid prior to irradiation, only the singlet oxygen quencher-lutein significantly protected against fullerol photodamage. Apoptosis was observed in lens cells treated with fullerol whether or not the cells were irradiated, in the order UVA > visible light > dark. Dynamic light scattering (DLS) showed that in the presence of the endogenous lens protein α-crystallin, large aggregates of fullerol were reduced. In conclusion, fullerol is both cytotoxic and phototoxic to human lens epithelial cells. Although the acute toxicity of water-soluble nano-C60(OH)22-26 is low, these compounds are retained in the body for long periods, raising concern for their chronic toxic effect. Before fullerols are used to deliver drugs to the eye, they should be tested for photo- and cytotoxicity in vivo

  13. Control of mucosal virus infection by influenza nucleoprotein-specific CD8+ cytotoxic T lymphocytes

    Directory of Open Access Journals (Sweden)

    Couch Robert B

    2007-06-01

    Full Text Available Abstract Background MHC class I-restricted CD8+ cytotoxic T lymphocytes (CTL are thought to play a major role in clearing virus and promoting recovery from influenza infection and disease. This has been demonstrated for clearance of influenza virus from the lungs of infected mice. However, human influenza infection is primarily a respiratory mucosal infection involving the nasopharynx and tracheobronchial tree. The role of CD8+ CTL directed toward the influenza nucleoprotein (NP in defense against influenza virus infection at the respiratory mucosa was evaluated in two separate adoptive transfer experiments. Methods Influenza nucleoprotein (NP-specific CD8+ CTL were generated from splenocytes obtained from Balb/c mice previously primed with influenza A/Taiwan/1/86 (H1N1 infection or with influenza A/PR/8/34 (H1N1-derived NP plasmid DNA vaccine followed by infection with A/Hong Kong/68 (H3N2 virus. After in vitro expansion by exposure to an influenza NP-vaccinia recombinant, highly purified CD8+ T cells exhibited significant lysis in vitro of P815 target cells infected with A/Hong Kong/68 (H3N2 virus while the CD8- fraction (CD4+ T cells, B cells and macrophages had no CTL activity. Purified CD8+ and CD8- T cells (1 × 107 were injected intravenously or interperitoneally into naive mice four hours prior to intranasal challenge with A/HK/68 (H3N2 virus. Results The adoptively transferred NP-vaccinia-induced CD8+ T cells caused significant reduction of virus titers in both the lungs and nasal passages when compared to CD8- cells. Neither CD8+ nor CD8- T cells from cultures stimulated with HIV gp120-vaccinia recombinant reduced virus titers. Conclusion The present data demonstrate that influenza NP-specific CD8+ CTL can play a direct role in clearance of influenza virus from the upper respiratory mucosal surfaces.

  14. T-2 toxin-induced cytotoxicity and damage on TM3 Leydig cells.

    Science.gov (United States)

    Yuan, Zhihang; Matias, Froilan Bernard; Yi, Jin-E; Wu, Jing

    2016-01-01

    T-2 toxin is a highly toxic mycotoxin produced by various Fusarium species, mainly, Fusarium sporotrichoides, and has been reported to have toxic effects on reproductive system of adult male animals. This study investigated the dose-dependent cytotoxicity of T-2 toxin on reproductive cells using TM3 Leydig cells. Specifically, the cytotoxic effect of T-2 toxin was assessed by measuring cell viability; lactate dehydrogenase (LDH); malondialdehyde (MDA); antioxidant activity by measuring superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and DNA damage; and cell apoptosis. Results showed that T-2 toxin is highly cytotoxic on TM3 Leydig cells. However, Trolox-treated TM3 Leydig cells showed significantly reduced oxidative damage, DNA damage, and apoptosis induced by T-2 toxin. This study proves that T-2 toxin can damage the testes and thus affects the reproductive capacity of animals and humans. Furthermore, oxidative stress plays an important role in the cytotoxic effect of T-2 toxin. PMID:26707243

  15. Poly (D,L-lactide-co-glycolide) nanoparticles: Uptake by epithelial cells and cytotoxicity

    OpenAIRE

    J. H. Hamman; L. A. Nkabinde; Shoba-Zikhali, L.N.N.; Semete-Makokotlela, B.; Kalombo, L.; H. Swai; Grobler, A.

    2014-01-01

    Nanoparticles as drug delivery systems offer benefits such as protection of the encapsulated drug against degradation, site-specific targeting and prolonged blood circulation times. The aim of this study was to investigate nanoparticle uptake into Caco-2 cell monolayers, their co-localization within the lysosomal compartment and their cytotoxicity in different cell lines. Rhodamine-6G labelled poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles were prepared by a double emulsion solvent evapo...

  16. Poly (D,L-lactide-co-glycolide) nanoparticles: uptake by epithelial cells and cytotoxicity

    OpenAIRE

    L. A. Nkabinde; Shoba-Zikhali, L.N.N.; Semete-Makokotlela, B.; Grobler, A.; J. H. Hamman

    2014-01-01

    Nanoparticles as drug delivery systems offer benefits such as protection of the encapsulated drug against degradation, site-specific targeting and prolonged blood circulation times. The aim of this study was to investigate nanoparticle uptake into Caco-2 cell monolayers, their co-localization within the lysosomal compartment and their cytotoxicity in different cell lines. Rhodamine-6G labelled poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles were prepared by a double emulsion s...

  17. Investigation of the cytotoxicity of CCVD carbon nanotubes towards human umbilical vein endothelial cells

    OpenAIRE

    Flahaut, Emmanuel; Durrieu, Marie-Christine; Remy-Zolghadri, Murielle; Bareille, Reine; Baquey, Charles

    2006-01-01

    The cytotoxicity of different samples of carbon nanotubes synthesised by catalytic chemical vapour deposition was investigated towards human umbilical vein endothelial cells, using two cytotoxicity standard assays (neutral red assay for the cell viability and MTT assay—tetrazolinium salt—for the cell metabolic activity). No cytotoxicity was found for any sample.

  18. Cytotoxicity and glutathione depletion studies using CHOK cells

    International Nuclear Information System (INIS)

    Radiosensitization characteristics of newly synthesized isoindole-4, 7-diones have been established in the authors' laboratories. Cytotoxicity studies of isoindole-4, 7-diones on chinese hamster ovary cell (CHOK) have been carried out. The effects that different concentrations of isoindole-4, 7-diones have on cell growth as a function of time after treatment on both systems (oxic and hypoxic) have been determined. Most of isoindole-4, 7-diones used in these studies show more cytotoxic effect under hypoxic conditions. Gluthathione depletion was also measured in both systems. Most of the quinones studied deplete the concentration of glutathione in the CHOK cells. The results will be compared with similar studies carried out with the well known radiosensitizers misonidazole. It is hoped that the isoindole-r, 7-diones are a new family of chemical radiosensitizers

  19. Effects of Ginkgo biloba extract on cell proliferation and cytotoxicity in human hepatocellular carcinoma cells

    OpenAIRE

    Chao, Jane CJ; Chu, Chia Chou

    2004-01-01

    AIM: To study the effect of Ginkgo biloba extract (EGb 761) containing 22%-27% flavonoids (ginkgo-flavone glycosides) and 5%-7% terpenoids (ginkgolides and bilobalides) on cell proliferation and cytotoxicity in human hepatocellular carcinoma (HCC) cells.

  20. In vitro study on the biotransformation and cytotoxicity of three hexabromocyclododecane diastereoisomers in liver cells.

    Science.gov (United States)

    Huang, Xiaomei; Chen, Cen; Shang, Yu; Zhong, Yufang; Ren, Guofa; Yu, Zhiqiang; An, Jing

    2016-10-01

    In order to clarify the cytotoxicity of hexabromocyclododecane (HBCD) diastereoisomers, and to investigate the correlation of cytotoxicity and biotransformation of HBCDs, the immortalized human liver cells L02 and human hepatoma cells HepG2 were exposed to individual HBCD diastereoisomer (α-, β- and γ-HBCD). Cytotoxicity was assayed in terms of cell viability, reactive oxygen species (ROS) level and DNA damage. Metabolic rate, bioisomerization and enantiomer fractions were analyzed using the liquid chromatograph coupled to triple quadrupole mass spectrometer (LC-MS/MS). The α-, β- and γ-HBCD all had cytotoxicity in L02 and HepG2 cells with the toxicity order β-HBCD ≥ γ-HBCD > α-HBCD according to the results of proliferation assay. The cytotoxicity mechanism between the two cells seemed different: a) the stability of intracellular redox state plays an important role in inducing cell toxicity in HepG2 cells. b) DNA damage status is central to inhibit proliferation in L02 cells. The metabolic capability of HepG2 was superior to L02 for HBCD diastereoisomers, which may explain the greater toxicity of HBCDs in HepG2 cells. The bioisomerization and enantiomer enrichment were also detected in this study, although the results were inconsistent with other reports, which might result from species-specific differences in HBCDs metabolism or experimental conditions. The cytotoxicity and metabolic mechanism of individual enantiomers must be further investigated to evaluate the health risks of HBCDs. PMID:27434255

  1. Selective cytotoxicity of benzyl isothiocyanate in the proliferating fibroblastoid cells.

    Science.gov (United States)

    Miyoshi, Noriyuki; Uchida, Koji; Osawa, Toshihiko; Nakamura, Yoshimasa

    2007-02-01

    In the present study, experiments using presynchronization culture cells demonstrated that benzyl ITC (BITC), previously isolated from a tropical papaya fruit extract, induced the cytotoxic effect preferentially in the proliferating human colon CCD-18Co cells to the quiescent ones. Quiescent CCD-18Co cells were virtually unaffected by BITC and marginal cytotoxicity was observed at 15 microM. We observed that BITC dramatically induced the p53 phosphorylation and stabilization only in the quiescent (G(0)/G(1) phase-arrested) cells, but not significantly in the proliferating human colon CCD-18Co cells when compared with quiescent ones. We also observed ataxia telangiectasia-mutated (ATM) phosphorylation in the quiescent cells. The BITC-induced p53 phosphorylation was counteracted by caffeine treatment, implying the involvement of an ATM/ataxia telangiectasia and Rad3-related kinase signaling pathway. Moreover, downregulation of p53 by a siRNA resulted in the enhancement of susceptibility to undergo apoptosis by BITC. We also showed here that depletion of p53 abrogated G(0)/G(1) arrest accompanied by the declined expression of p21(waf1/cip1) and p27(kip1) in CCD-18Co cells. In conclusion, we identified p53 as a potential negative regulator of the apoptosis induction by BITC in the normal colon CCD-18Co cells through the inhibition of cell-cycle progression at the G(0)/G(1) phase. PMID:17096346

  2. Hexavalent chromium is cytotoxic and genotoxic to American alligator cells.

    Science.gov (United States)

    Wise, Sandra S; Wise, Catherine; Xie, Hong; Guillette, Louis J; Zhu, Cairong; Wise, John Pierce; Wise, John Pierce

    2016-02-01

    Metals are a common pollutant in the aquatic ecosystem. With global climate change, these levels are anticipated to rise as lower pH levels allow sediment bound metals to be released. The American alligator (Alligator mississippiensis) is an apex predator in the aquatic ecosystem and is considered a keystone species; as such it serves as a suitable monitor for localized pollution. One metal of increasing concern is hexavalent chromium (Cr(VI)). It is present in the aquatic environment and is a known human carcinogen and reproductive toxicant. We measured the cytotoxicity and genotoxicity of Cr(VI) in American alligator cells derived from scute tissue. We found that particulate and soluble Cr(VI) are both cytotoxic and genotoxic to alligator cells in a concentration-dependent manner. These data suggest that alligators may be used as a model for assessing the effects of environmental Cr(VI) contamination as well as for other metals of concern. PMID:26730726

  3. Virus elimination in acute lymphocytic choriomeningitis virus infection. Correlation with virus-specific delayed-type hypersensitivity rather than cytotoxicity

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Volkert, M; Bro-Jørgensen, K

    1983-01-01

    The immunological effector mechanism responsible for the elimination of virus in murine acute non-fatal extracranial lymphocytic choriomeningitis virus infection was studied. In this infection virus clearance is generally regarded as the result of a direct action of virus-specific cytotoxic T cells...... (Tc cells) on virus-producing target cells in the infected mouse. However, by manipulating the antiviral immune response by pretreatment with various doses of cyclophosphamide, we found lack of correlation between Tc-cell activity and the clearance of virus. In contrast, we observed a conspicuous...... correlation between the host's ability to mount a virus-specific delayed-type hypersensitivity (DTH) response and its capacity to combat virus. Moreover, pretreatment with silica and carrageenan prolonged viraemia without impairment of the peak Tc-cell response. These findings indicate that Tc cells have...

  4. Rational Development of a Cytotoxic Peptide to Trigger Cell Death

    OpenAIRE

    Boohaker, Rebecca J.; Zhang, Ge; Lee, Michael W; Nemec, Kathleen N.; Santra, Santimukul; Perez, J Manuel; Khaled, Annette R.

    2012-01-01

    Defects in the apoptotic machinery can contribute to tumor formation and resistance to treatment, creating a need to identify new agents that kill cancer cells by alternative mechanisms. To this end, we examined the cytotoxic properties of a novel peptide, CT20p, derived from the C-terminal, alpha-9 helix of Bax, an amphipathic domain with putative membrane binding properties. Like many anti-microbial peptides, CT20p contains clusters of hydrophobic and cationic residues that could enable the...

  5. Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro

    OpenAIRE

    Meier, Daniela; Campanile, Carmen; Botter, Sander M.; Born, Walter; Fuchs, Bruno

    2014-01-01

    In recent years, there has been the difficulty in finding more effective therapies against cancer with less systemic side effects. Therefore Photodynamic Therapy is a novel approach for a more tumor selective treatment. Photodynamic Therapy (PDT) that makes use of a nontoxic photosensitizer (PS), which, upon activation with light of a specific wavelength in the presence of oxygen, generates oxygen radicals that elicit a cytotoxic response(1). Despite its approval almost twenty years ago by th...

  6. Cytotoxicity of modified glass ionomer cement on odontoblast cells.

    Science.gov (United States)

    Chen, Song; Mestres, Gemma; Lan, Weihua; Xia, Wei; Engqvist, Håkan

    2016-07-01

    Recently a modified glass ionomer cement (GIC) with enhanced bioactivity due to the incorporation of wollastonite or mineral trioxide aggregate (MTA) has been reported. The aim of this study was to evaluate the cytotoxic effect of the modified GIC on odontoblast-like cells. The cytotoxicity of a conventional GIC, wollastonite modified GIC (W-mGIC), MTA modified GIC (M-mGIC) and MTA cement has been evaluated using cement extracts, a culture media modified by the cement. Ion concentration and pH of each material in the culture media were measured and correlated to the results of the cytotoxicity study. Among the four groups, conventional GIC showed the most cytotoxicity effect, followed by W-mGIC and M-mGIC. MTA showed the least toxic effect. GIC showed the lowest pH (6.36) while MTA showed the highest (8.62). In terms of ion concentration, MTA showed the largest Ca(2+) concentration (467.3 mg/L) while GIC showed the highest concentration of Si(4+) (19.9 mg/L), Al(3+) (7.2 mg/L) and Sr(2+) (100.3 mg/L). Concentration of F(-) was under the detection limit (0.02 mg/L) for all samples. However the concentrations of these ions are considered too low to be toxic. Our study showed that the cytotoxicity of conventional GIC can be moderated by incorporating calcium silicate based ceramics. The modified GIC might be promising as novel dental restorative cements. PMID:27221819

  7. Increased natural killer-cell mobilization and cytotoxicity during marital conflict.

    Science.gov (United States)

    Dopp, J M; Miller, G E; Myers, H F; Fahey, J L

    2000-03-01

    Natural killer (NK) cells are reproducibly mobilized into the circulation in response to intense physical exercise or acute psychological stress, and altered expression of adhesion molecules potentially contributes to NK-cell mobilization. Studies of leukocyte mobilization during acute stress have used psychological stressors which facilitate tight experimental control but have limited applicability to everyday life. We therefore used a laboratory model of marital conflict as an experientially meaningful acute stressor to elucidate relationships among conflict, cardiovascular reactivity, and altered leukocyte phenotype and function. Forty-one ethnically diverse, nondistressed, healthy married couples were asked to discuss a specific problem in their marriage for 15 min. Blood pressure and heart rate were measured before, during, and after the discussion, and blood was remotely drawn at the same time points to quantify numbers of specific leukocyte subsets, NK-cell adhesion molecule expression, and NK cytotoxicity. Couples responded to the conflict task with cardiovascular reactivity; increases in the percentages of circulating NK cells and CD8(+) T cells and decreases in the percentage of circulating CD4(+) T cells; decreases in the percentage of NK cells that express L-selectin; and increases in NK-cell cytotoxicity without a commensurate increase in per-cell cytotoxicity. Rapid downregulation or shedding of L-selectin (CD62L) from NK cells did not contribute to their mobilization during conflict. Instead, CD62L(-) NK cells were mobilized while CD62L(+) NK cells were selectively retained in the vascular marginating pool and/or in extravascular tissue. From a broader perspective, the data support the hypothesis that altered trafficking of specific leukocyte subsets is an integral component of the fight-or-flight response to an acute stressor. PMID:10729214

  8. C22:0- and C24:0-dihydroceramides confer mixed cytotoxicity in T-cell acute lymphoblastic leukemia cell lines.

    Directory of Open Access Journals (Sweden)

    Michael W Holliday

    Full Text Available We previously reported that fenretinide (4-HPR was cytotoxic to acute lymphoblastic leukemia (ALL cell lines in vitro in association with increased levels of de novo synthesized dihydroceramides, the immediate precursors of ceramides. However, the cytotoxic potentials of native dihydroceramides have not been defined. Therefore, we determined the cytotoxic effects of increasing dihydroceramide levels via de novo synthesis in T-cell ALL cell lines and whether such cytotoxicity was dependent on an absolute increase in total dihydroceramide mass versus an increase of certain specific dihydroceramides. A novel method employing supplementation of individual fatty acids, sphinganine, and the dihydroceramide desaturase-1 (DES inhibitor, GT-11, was used to increase de novo dihydroceramide synthesis and absolute levels of specific dihydroceramides and ceramides. Sphingolipidomic analyses of four T-cell ALL cell lines revealed strong positive correlations between cytotoxicity and levels of C22:0-dihydroceramide (ρ = 0.74-0.81, P ≤ 0.04 and C24:0-dihydroceramide (ρ = 0.84-0.90, P ≤ 0.004, but not between total or other individual dihydroceramides, ceramides, or sphingoid bases or phosphorylated derivatives. Selective increase of C22:0- and C24:0-dihydroceramide increased level and flux of autophagy marker, LC3B-II, and increased DNA fragmentation (TUNEL assay in the absence of an increase of reactive oxygen species; pan-caspase inhibition blocked DNA fragmentation but not cell death. C22:0-fatty acid supplemented to 4-HPR treated cells further increased C22:0-dihydroceramide levels (P ≤ 0.001 and cytotoxicity (P ≤ 0.001. These data demonstrate that increases of specific dihydroceramides are cytotoxic to T-cell ALL cells by a caspase-independent, mixed cell death mechanism associated with increased autophagy and suggest that dihydroceramides may contribute to 4-HPR-induced cytotoxicity. The targeted increase of specific acyl chain dihydroceramides

  9. α-Mangostin Enhances Betulinic Acid Cytotoxicity and Inhibits Cisplatin Cytotoxicity on HCT 116 Colorectal Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Amin Malik Shah Abdul Majid

    2012-03-01

    Full Text Available Despite the progress in colon cancer treatment, relapse is still a major obstacle. Hence, new drugs or drug combinations are required in the battle against colon cancer. α-Mangostin and betulinic acid (BA are cytotoxic compounds that work by inducing the mitochondrial apoptosis pathway, and cisplatin is one of the most potent broad spectrum anti-tumor agents. This study aims to investigate the enhancement of BA cytotoxicity by α-mangostin, and the cytoprotection effect of α-mangostin and BA on cisplatin-induced cytotoxicity on HCT 116 human colorectal carcinoma cells. Cytotoxicity was investigated by the XTT cell proliferation test, and the apoptotic effects were investigated on early and late markers including caspases-3/7, mitochondrial membrane potential, cytoplasmic shrinkage, and chromatin condensation. The effect of α-mangostin on four signalling pathways was also investigated by the luciferase assay. α-Mangostin and BA were more cytotoxic to the colon cancer cells than to the normal colonic cells, and both compounds showed a cytoprotective effect against cisplatin-induced cytotoxicity. On the other hand, α-mangostin enhanced the cytotoxic and apoptotic effects of BA. Combination therapy hits multiple targets, which may improve the overall response to the treatment, and may reduce the likelihood of developing drug resistance by the tumor cells. Therefore, α-mangostin and BA may provide a novel combination for the treatment of colorectal carcinoma. The cytoprotective effect of the compounds against cisplatin-induced cytotoxicity may find applications as chemopreventive agents against carcinogens, irradiation and oxidative stress, or to neutralize cisplatin side effects.

  10. The production of podophyllotoxin and related cytotoxic lignans by plant cell cultures

    OpenAIRE

    Uden, Wilhelmus van

    1992-01-01

    Podophyllotoxin is a lignan that occurs in several plant species. Its cytotoxic activity is well-known, but it can not be applied clinically because of severe toxic side effects. Attempts have been undertaken to develop less toxic and more specifically acting antitumour drugs derived from podophyllotoxin. Presently, etoposide and teniposide are clinically applied chemotherapeutics that are especially effective against testicular and small cell lung cancer. Podophyllotoxin is the starting comp...

  11. Antitumor and cytotoxic properties of a humanized antibody specific for the GM3(Neu5Gc) ganglioside.

    Science.gov (United States)

    Dorvignit, Denise; García-Martínez, Liliana; Rossin, Aurélie; Sosa, Katya; Viera, Justo; Hernández, Tays; Mateo, Cristina; Hueber, Anne-Odile; Mesa, Circe; López-Requena, Alejandro

    2015-12-01

    Gangliosides are sialic acid-bearing glycosphingolipids expressed on all mammalian cell membranes, and participate in several cellular processes. During malignant transformation their expression changes, both at the quantitative and qualitative levels. Of particular interest is the overexpression by tumor cells of Neu5Gc-gangliosides, which are absent, or detected in trace amounts, in human normal cells. The GM3(Neu5Gc) ganglioside in particular has been detected in many human tumors, and it is considered one of the few tumor specific antigen. We previously demonstrated that a humanized antibody specific for this molecule, named 14F7hT, retained the binding and cytotoxic properties of the mouse antibody. In this work, we confirm that 14F7hT exerts a non-apoptotic cell death mechanism in vitro and shows its potent in vivo antitumor activity on a solid mouse myeloma model. Also, we demonstrate, in contrast to the murine counterpart, the capacity of this antibody to induce antibody-dependent cell-mediated cytotoxicity using human effector cells, which increases its potential for the treatment of GM3(Neu5Gc)-expressing human tumors. PMID:26224247

  12. CD85/LIR-1/ILT2 and CD152 (Cytotoxic T Lymphocyte Antigen 4) Inhibitory Molecules Down-Regulate the Cytolytic Activity of Human CD4+ T-Cell Clones Specific for Mycobacterium tuberculosis

    OpenAIRE

    Merlo, Andrea; Saverino, Daniele; Tenca, Claudya; Grossi, Carlo Enrico; Bruno, Silvia; Ciccone, Ermanno

    2001-01-01

    Antigen-specific cytolytic CD4+ T lymphocytes control Mycobacterium tuberculosis infection by secreting cytokines and by killing macrophages that have phagocytosed the pathogen. However, lysis of the latter cells promotes microbial dissemination, and other macrophages engulf the released bacteria. Subsequently, CD4+ T-cell-mediated killing of macrophages goes on, and this persistent process may hamper control of infection, unless regulatory mechanisms maintain a subtle balance between lysis o...

  13. The Role of Dextran Coatings on the Cytotoxicity Properties of Ceria Nanoparticles Toward Bone Cancer Cells

    Science.gov (United States)

    Yazici, Hilal; Alpaslan, Ece; Webster, Thomas J.

    2015-04-01

    Cerium oxide nanoparticles have demonstrated great potential as antioxidant and radioprotective agents for nanomedicine applications especially for cancer therapy. The surface chemistry of nanoparticles is an important property that has a significant effect on their performance in biological applications including cancer diagnosis, cancer treatment, and bacterial infection. Recently, various nanosized cerium oxide particles with different types of polymer coatings have been developed to improve aqueous solubility and allow for surface functionalization for distinct applications. In this study, the role of ceria nanoparticles coated with dextran on the cytotoxicity properties of bone cancer cells was shown. Specifically, 0.1 M and 0.01 M dextran-coated, bone cancer cells was observed for the 0.01 M dextran coating after 3 days compared with the 0.1 M dextran coating. These results indicated that surface dextran functionalization had a positive impact on the cytotoxicity of cerium oxide nanoparticles against osteosarcoma cells.

  14. Cell-specific regulation of apoptosis by designed enediynes.

    OpenAIRE

    Nicolaou, K. C.; Stabila, P; Esmaeli-Azad, B; Wrasidlo, W; Hiatt, A

    1993-01-01

    The naturally occurring enediyne antibiotics are a unique class of antitumor drugs that combine reactive enediynes with additional structural features conferring affinity for DNA. Dynemicin A, in which an enediyne core is attached to an anthraquinone group capable of DNA intercalation, readily cleaves double-stranded DNA. This activity is thought to be the basis of its potent antitumor cytotoxicity. To investigate cell-specific mechanisms of cytotoxicity in the absence of DNA affinity, we hav...

  15. Armed and accurate: engineering cytotoxic T cells for eradication of leukemia

    Directory of Open Access Journals (Sweden)

    Radic Marko

    2012-02-01

    Full Text Available Abstract Translational medicine depends on a rapid and efficient exchange of results between the bench and the bedside. A recent example from the field of cancer immunotherapy highlights the essential nature of this exchange. Methods have been developed to convert a patient's cytotoxic T cells into efficient and specific killers of cancer cells in patients with leukemia. By using recombinant DNA techniques, a lentiviral vector was constructed to express chimeric antigen receptors in cytotoxic T cells from patients with advanced chronic lymphocytic leukemia. The purpose of the chimeric receptors was to direct the cytotoxic T cell activity against cells causing the cancer. The effect of infusing the engineered T cells back into the cancer patients was tested in a Phase I trial at the University of Pennsylvania, and the initial results were described in two articles from the research team of Dr. Carl June. The remarkable success of this trial should energize further applications of biotechnology in the development of new cancer immunotherapies.

  16. Preferentially Cytotoxic Constituents of Andrographis paniculata and their Preferential Cytotoxicity against Human Pancreatic Cancer Cell Lines.

    Science.gov (United States)

    Lee, Sullim; Morita, Hiroyuki; Tezuka, Yasuhiro

    2015-07-01

    In the course of our search for anticancer agents based on a novel anti-austerity strategy, we found that the 70% EtOH extract of the crude drug Andrographis Herba (aerial parts of Andrographis paniculata), used in Japanese Kampo medicines, killed PANC-1 human pancreatic cancer cells preferentially in nutrient-deprived medium (NDM). Phytochemical investigation of the 70% EtOH extract led to the isolation of 21 known compounds consisting of six labdane-type diterpenes (11, 15, 17-19, 21), six flavones (5, 7, 10, 12, 14, 20), three flavanones (2, 6, 16), two sterols (3, 8), a fatty acid (1), a phthalate (4), a triterpene (9), and a monoterpene (13). Among them, 14-deoxy-11,12-didehydroandrographolide (17) displayed the most potent preferential cytotoxicity against PANC-1 and PSN-1 cells with PC50 values of 10.0 μM and 9.27 μM, respectively. Microscopical observation, double staining with ethidium bromide (EB) and acridine orange (AO), and flow cytometry with propidium iodide/annexin V double staining indicated that 14-deoxy-11,12-didehydroandrographolide (17) triggered apoptosis-like cell death in NDM with an amino acids and/or serum-sensitive mode. PMID:26410998

  17. Cytotoxicity of yellow sand in lung epithelial cells

    Indian Academy of Sciences (India)

    Y H Kim; K S Kim; N J Kwak; K H Lee; S A Kweon; Y Lim

    2003-02-01

    The present study was carried out to observe the cytotoxicity of yellow sand in comparison with silica and titanium dioxide in a rat alveolar type II cell line (RLE-6TN). Yellow sand (China Loess) was obtained from the loess layer in the Gunsu Province of China. The mean particle diameter of yellow sand was about 0.003 ± 0.001 mm. Major elements of yellow sand were Si(27.7 ± 0.6%), Al(6.01 ± 0.17%), and Ca(5.83 ± 0.23%) in that order. Silica and yellow sand significantly decreased cell viability and increased [Ca2+]i. All three particles increased the generation of H2O2. TiO2 did not change Fenton activity, while silica induced a slight increase of Fenton activity. In contrast, yellow sand induced a significant increase of Fenton activity. Silica, yellow sand and TiO2 induced significant nitrite formations in RLE-6TN cells. Silica showed the highest increase in nitrite formation, while yellow sand induced the least formation of nitrite. Silica and yellow sand increased the release of TNF-. Based on these results, we suggest that yellow sand can induce cytotoxicity in RLE-6TN cells and reactive oxygen species, Fenton activity and reactive nitrogen species might be involved in this toxicity.

  18. Cytotoxic effects of catechols to glial and neuronal cells

    Directory of Open Access Journals (Sweden)

    Ramon Santos El-Bachá

    2015-04-01

    Full Text Available Catechols are compounds that autoxidises under physiological conditions leading to the formation of reactive oxygen species (ROS, semiquinones, and quinones. These molecules can be formed in organisms because of the metabolism of exogenous aromatic substances, such as benzene. However, there are several important endogenous catechols, which have physiological functions, such as catecholamines. Furthermore, several pharmacological agents are catechols, such as apomorphine, or can be metabolised to generate these compounds. In this presentation we will show that apomorphine can unspecifically bind to proteins during its autoxidation, a phenomenon that is inhibited by thiols. Brain endothelial cells and glial cells express xenobiotic-metabolising enzymes as components of the metabolic blood-brain barrier in an attempt to protect the central nervous system against drugs. Since UDP-glucuronosyltransferases (EC 2.4.1.17 are among these enzymes, we investigated the ability of brain microsomes to conjugate catechols with glucuronate. Despite the fact that 1-naphtol could be glucuronidated in the presence of brain cortex microsomes, the same was not observed for most of catechols that were tested. Therefore, this is not the main mechanism used to protect the brain against them. Indeed, catechols may inhibit other xenobiotic-metabolising enzymes. We showed that apomorphine inhibited the cytochrome P450-dependent dealkylation activity. The production of ROS and reactive quinones, as well as their effects on protein functions, seems to be involved in the cytotoxicity of catechols. Glial cells are more resistant than neuronal cells. Apomorphine was more toxic to rat neurons than to rat C6 glioma cells. 1,2-Dihydroxybenzene (catechol killed human GL-15 cells with an EC50 of 230 uM after 72 h, a effect that was significantly inhibited by superoxide dismutase (EC 1.15.1.1. Another mechanism that we found to be involved in catechol cytotoxicity is the inhibition

  19. In vitro cytotoxicity of transparent yellow iron oxide nanoparticles on human glioma cells.

    Science.gov (United States)

    Wang, Yun; Zhu, Mo-Tao; Wang, Bing; Wang, Meng; Wang, Hua-Jian; OuYang, Hong; Feng, Wei-Yue

    2010-12-01

    With rapid development of nanotechnology, concerns about the possible adverse health effects on human beings by using nanomaterials have been raised. Transparent yellow iron oxide (alpha-FeOOH) nanoparticles have been widely used in paints, plastic, rubber, building materials, papermaking, food products and pharmaceutical industry, thus the potential health implications by the exposure should be considered. The purpose of this study is to assess the cytotoxicity of transparent yellow iron oxide nanoparticles on U251 human glioma cells. The alpha-FeOOH nanoparticles are in clubbed shapes with 9 nm in diameter and 43 nm long. The specific surface area is 115.3 m2/g. After physicochemical characterization of the nanoparticles, U251 cells were exposed to a-FeOOH at the doses of 0, 3.75, 15, 60 and 120 microg/mL. The results showed that the alpha-FeOOH nanoparticles reduced the cell viability and induced necrosis and apoptosis in U251 cells. In addition, nanoparticle exposure significantly increased the levels of superoxide anion and nitric oxide in a dose-dependent fashion in the cells. Our results suggest that exposure to alpha-FeOOH nanoparticles induce significant free radical formation and cytotoxic effects. The large surface area that induced high surface reactivity may play an important role in the cytotoxic effect of alpha-FeOOH nanoparticles. PMID:21121365

  20. A chimeric fusion of the hASH1 and EZH2 promoters mediates high and specific reporter and suicide gene expression and cytotoxicity in small cell lung cancer cells

    DEFF Research Database (Denmark)

    Poulsen, T.T.; Pedersen, N.; Juel, H.;

    2008-01-01

    Transcriptionally targeted gene therapy is a promising experimental modality for treatment of systemic malignancies such as small cell lung cancer (SCLC). We have identified the human achaete-scute homolog 1 (hASH1) and enhancer of zeste homolog 2 (EZH2) genes as highly upregulated in SCLC compared...

  1. Cytotoxic mechanisms of murine lymphokine-activated killer cells: functional and biochemical characterization of homogeneous populations of spleen LAK cells.

    Science.gov (United States)

    Zychlinsky, A; Joag, S; Liu, C C; Young, J D

    1990-04-01

    A highly purified population of murine lymphokine-activated killer (LAK) cells was obtained by selecting plastic-adherent splenocytes after incubation in high doses of recombinant IL-2. The population obtained was shown to be more than 95% positive for the cell marker asialo-GM1, and negative for both Lyt-1 (CD5) and Lyt-2 (CD8). The cells presented typical large granular lymphocyte morphology, and killed NK-susceptible target cells in an exclusively calcium-dependent fashion. A target cell DNA fragmentation activity of LAK cells could be detected even before target cell death. The presence of Hanukkah Factor/granzyme A/serine esterase 1, CTLA-1/granzyme B/serine esterase 2, and pore-forming protein (PFP/perforin) in these LAK cells was demonstrated by Northern blot analysis, suggesting that these markers are not exclusively associated with cytotoxic T lymphocytes. On immunoblots, antibodies specific for a lymphocyte PFP/perforin reacted with a 70-kDa protein of LAK cells. PFP/perforin was localized by immunofluorescence to the cell granules. A 50-kDa protein antigenically related to the macrophage cytokine tumor necrosis factor (TNF) was detected by immunoblotting and localized by immunofluorescence to both the cell granules and the cytosol. No RNA for TNF, however, could be detected using TNF-specific probes, suggesting that LAK cells may contain a cytotoxic factor which is related to, but distinct from, TNF. The work presented here demonstrates that cytotoxic mediators identified in cell lines are also present in primary cell cultures. PMID:1690083

  2. Suppressor T cells, distinct from "veto cells," are induced by alloantigen priming and mediate transferable suppression of cytotoxic T lymphocyte responses in vivo

    DEFF Research Database (Denmark)

    Owens, T; Crispe, I N

    1985-01-01

    Primary and secondary cytotoxic T lymphocyte responses to minor alloantigens can be suppressed by priming host mice with a high dose (10(8) cells) of alloantigenic donor spleen cells (SC). Such suppression is antigen specific and transferable into secondary hosts with T cells. One interpretation ...

  3. "Proliferation of cytotoxic and activated T cells during acute Epstein-Barr virus induced Infectious Mononucleosis "

    Directory of Open Access Journals (Sweden)

    Mansoori SD

    2002-05-01

    Full Text Available The immune responses that develop following Epstien-Barr Virus (EBV infection are complex and involve both humoral and to a greater extent cell-mediated immune mechanisms. To evaluate the immune response, flow cytometric analysis of the peripheral blood of six patients during the acute phase of EBV infection was performed. This analysis revealed a significant increase in the percentages and the absolute number of CD8+cytotoxic and activated (HLA-DR+ - T lymphocytes and in some cases with a concomitan decrease in the percentages of B (CD19+ lymphocytes and T helper (CD4+ lymphocytes. These patient invariably had inverted CD4/CD8 ratio. All changes reversed to normal level during the recovery phase of infection. It is therefore concluded that EBV specific cytotoxic and activated T lymphocytes are essential in controlling acute EBV infection presented by the infected B cells.

  4. Normal human serum contains a natural IgM antibody cytotoxic for human neuroblastoma cells.

    Science.gov (United States)

    Ollert, M W; David, K; Schmitt, C; Hauenschild, A; Bredehorst, R; Erttmann, R; Vogel, C W

    1996-04-30

    Neuroblastoma (NB) is characterized by the second highest spontaneous regression of any human malignant disorder, a phenomenon that remains to be elucidated. In this study, a survey of 94 normal human adult sera revealed a considerable natural humoral cytotoxicity against human NB cell lines in approximately one-third of the tested sera of both genders. Specific cell killing by these sera was in the range of 40% to 95%. Serum cytotoxicity was dependent on an intact classical pathway of complement. By several lines of evidence, IgM antibodies were identified as the cytotoxic factor in the sera. Further analyses revealed that a 260-kDa protein was recognized by natural IgM of cytotoxic sera in Western blots of NB cell extracts. The antigen was expressed on the surface of seven human NB cell lines but not on human melanoma or other control tumor cell lines derived from kidney, pancreas, colon, bone, skeletal muscle, lymphatic system, and bone marrow. Furthermore, no reactivity was observed with normal human fibroblasts, melanocytes, and epidermal keratinocytes. The antigen was expressed in vivo as detected by immunohistochemistry in both the tumor of a NB patient and NB tumors established in nude rats from human NB cell lines. Most interestingly, the IgM anti-NB antibody was absent from the sera of 11 human NB patients with active disease. The anti-NB IgM also could not be detected in tumor tissue obtained from a NB patient. Collectively, our data suggest the existence of a natural humoral immunological tumor defense mechanism, which could account for the in vivo phenomenon of spontaneous NB tumor regression. PMID:8633097

  5. Cytotoxic activity of allogeneic natural killer cells on U251 glioma cells in vitro.

    Science.gov (United States)

    Guo, Meng; Wu, Tingting; Wan, Lixin

    2016-07-01

    The present study aimed to observe the cytotoxic activity of allogeneic natural killer (NK) cells on U251 glioma cells and to investigate their mechanism of action to establish an effective treatment strategy for neuroglioma. Cell survival curves, colony formation assays and karyotype analysis were performed to investigate the characteristics of U251 glioma cells. The present study demonstrated that natural killer group 2, member D (NKG2D)‑major histocompatibility complex class I‑related chain A/B (MICA/B) interactions contributed to the cytotoxic effect of NK cells on K562 and U251 cells. In antibody‑blocking assays to inhibit NKG2D ligands, the cytotoxic activity was not completely attenuated, which suggested that other signaling pathways contribute to the cytotoxic activity of NK cells on tumor cells in addition to the NKG2D‑mediated activity. The present study identified that the expression levels of NKG2D ligands on the surface of target cells influenced the strength of the NK cell immune response. Furthermore, allogeneic NK cells were observed to kill glioma cells in vitro, and this anticancer activity is associated with the rate of NKG2D expression on the surface of glioma cells. PMID:27175912

  6. Cytotoxicity of Portuguese Propolis: The Proximity of the In Vitro Doses for Tumor and Normal Cell Lines

    Directory of Open Access Journals (Sweden)

    Ricardo C. Calhelha

    2014-01-01

    Full Text Available With a complex chemical composition rich in phenolic compounds, propolis (resinous substance collected by Apis mellifera from various tree buds exhibits a broad spectrum of biological activities. Recently, in vitro and in vivo data suggest that propolis has anticancer properties, but is the cytoxicity of propolis specific for tumor cells? To answer this question, the cytotoxicity of phenolic extracts from Portuguese propolis of different origins was evaluated using human tumor cell lines (MCF7—breast adenocarcinoma, NCI-H460—non-small cell lung carcinoma, HCT15—colon carcinoma, HeLa—cervical carcinoma, and HepG2—hepatocellular carcinoma, and non-tumor primary cells (PLP2. The studied propolis presented high cytotoxic potential for human tumor cell lines, mostly for HCT15. Nevertheless, excluding HCT15 cell line, the extracts at the GI50 obtained for tumor cell lines showed, in general, cytotoxicity for normal cells (PLP2. Propolis phenolic extracts comprise phytochemicals that should be further studied for their bioactive properties against human colon carcinoma. In the other cases, the proximity of the in vitro cytotoxic doses for tumor and normal cell lines should be confirmed by in vivo tests and may highlight the need for selection of specific compounds within the propolis extract.

  7. Organometallic iron(III-salophene exerts cytotoxic properties in neuroblastoma cells via MAPK activation and ROS generation.

    Directory of Open Access Journals (Sweden)

    Kyu Kwang Kim

    Full Text Available The objective of the present study was to investigate the specific effects of Iron(III-salophene (Fe-SP on viability, morphology, proliferation, cell cycle progression, ROS generation and pro-apoptotic MAPK activation in neuroblastoma (NB cells. A NCI-DTP cancer screen revealed that Fe-SP displayed high toxicity against cell lines of different tumor origin but not tumor type-specificity. In a viability screen Fe-SP exhibited high cytotoxicity against all three NB cell lines tested. The compound caused cell cycle arrest in G1 phase, suppression of cells progressing through S phase, morphological changes, disruption of the mitochondrial membrane depolarization potential, induction of apoptotic markers as well as p38 and JNK MAPK activation, DNA degradation, and elevated generation of reactive oxygen species (ROS in SMS-KCNR NB cells. In contrast to Fe-SP, non-complexed salophene or Cu(II-SP did not raise ROS levels in NB or SKOV-3 ovarian cancer control cells. Cytotoxicity of Fe-SP and activation of caspase-3, -7, PARP, pro-apoptotic p38 and JNK MAPK could be prevented by co-treatment with antioxidants suggesting ROS generation is the primary mechanism of cytotoxic action. We report here that Fe-SP is a potent growth-suppressing and cytotoxic agent for in vitro NB cell lines and, due to its high tolerance in previous animal toxicity studies, a potential therapeutic drug to treat NB tumors in vivo.

  8. Identification of cytotoxic drugs that selectively target tumor cells with MYC overexpression.

    Directory of Open Access Journals (Sweden)

    Anna Frenzel

    Full Text Available Expression of MYC is deregulated in a wide range of human cancers, and is often associated with aggressive disease and poorly differentiated tumor cells. Identification of compounds with selectivity for cells overexpressing MYC would hence be beneficial for the treatment of these tumors. For this purpose we used cell lines with conditional MYCN or c-MYC expression, to screen a library of 80 conventional cytotoxic compounds for their ability to reduce tumor cell viability and/or growth in a MYC dependent way. We found that 25% of the studied compounds induced apoptosis and/or inhibited proliferation in a MYC-specific manner. The activities of the majority of these were enhanced both by c-MYC or MYCN over-expression. Interestingly, these compounds were acting on distinct cellular targets, including microtubules (paclitaxel, podophyllotoxin, vinblastine and topoisomerases (10-hydroxycamptothecin, camptothecin, daunorubicin, doxorubicin, etoposide as well as DNA, RNA and protein synthesis and turnover (anisomycin, aphidicholin, gliotoxin, MG132, methotrexate, mitomycin C. Our data indicate that MYC overexpression sensitizes cells to disruption of specific pathways and that in most cases c-MYC and MYCN overexpression have similar effects on the responses to cytotoxic compounds. Treatment of the cells with topoisomerase I inhibitors led to down-regulation of MYC protein levels, while doxorubicin and the small molecule MYRA-A was found to disrupt MYC-Max interaction. We conclude that the MYC pathway is only targeted by a subset of conventional cytotoxic drugs currently used in the clinic. Elucidating the mechanisms underlying their specificity towards MYC may be of importance for optimizing treatment of tumors with MYC deregulation. Our data also underscores that MYC is an attractive target for novel therapies and that cellular screenings of chemical libraries can be a powerful tool for identifying compounds with a desired biological activity.

  9. Measurement of cell mediated cytotoxicity by post-labeling surviving target cells

    International Nuclear Information System (INIS)

    The 51Cr release assay (CRA) is the commonly accepted technique for measurement of cell mediated cytotoxicity. This assay shows some disadvantages when mononucleated cells of human peripheral blood (MNC) are used as effector and target cells. The uptake of 51Cr by PHA stimulated lymphocytes is low compared to the spontaneous release. In an attempt to develop a cytotoxicity assay suitable for human lymphocytes we used 14C-TdR to label target cells surviving after contact with effector cells. Cytotoxic lymphocytes were generated by incubation of MNC with irradiated allogeneic MNC for 6 days. On day 6 the effector cells are irradiated and cocultured with PHA stimulated target cells. Twenty-four hours later 14C-TdR is added. After an additional 24 h the cultures are harvested and 14C-TdR taken up by target cells is measured. It is shown that the effector cells are still cytotoxic after irradiation. These cells do not take up 14C-TdR. Cell-free supernatants do not influence the uptake of 14C-TdR by target cells. The results obtained with this assay correlate very well those obtained by the CRA, if the spontaneous release does not exceed 30%. (author)

  10. Selective cytotoxicity of marine algae extracts to several human leukemic cell lines

    OpenAIRE

    Harada, Hideki; Kamei, Yuto

    1997-01-01

    Extracts from 8 species of marine algae which showed selective cytotoxicity in our previous screening program, were further examined for cytotoxic spectra to five human leukemic cell lines. The extract from a red alga, Amphiroa zonata exhibited strong cytotoxicity to all human leukemic cell lines tested and murine leukemic cells L1210 at the final concentrations from 15 to 375 µg ml−1. Then the cytotoxicity was not found in normal human fibroblast HDF and murine normal cells NIH-3T3. The acti...

  11. Cytotoxicity of obacunone and obacunone glucoside in human prostate cancer cells involves Akt-mediated programmed cell death

    International Nuclear Information System (INIS)

    Highlights: • Possible mechanism of inhibiting LNCaP cells proliferation by obacunone and obacunone glucoside is demonstrated for the first time. • Inhibition of LNCaP cells by limonoids though induction of programmed cell death, inhibition of cell signaling and inflammatory pathways. • Limonoids exhibited multi-mode inhibition of androgen expression in LNCaP cells. - Abstract: Obacunone and obacunone glucoside (OG) are naturally occurring triterpenoids commonly found in citrus and other plants of the Rutaceae family. The current study reports the mechanism of cytotoxicity of citrus-derived obacunone and OG on human androgen-dependent prostate cancer LNCaP cells. Both limonoids exhibited time- and dose-dependent inhibition of cell proliferation, with more than 60% inhibition of cell viability at 100 μM, after 24 and 48 h. Analysis of fragmentation of DNA, activity of caspase-3, and cytosolic cytochrome-c in the cells treated with limonoids provided evidence for activation of programmed cell death by limonoids. Treatment of LNCaP cells with obacunone and OG resulted in dose-dependent changes in expression of proteins responsible for the induction of programmed cell death through the intrinsic pathway and down-regulation of Akt, a key molecule in cell signaling pathways. In addition, obacunone and OG also negatively regulated an inflammation-associated transcription factor, androgen receptor, and prostate-specific antigen, and activated proteins related to the cell cycle, confirming the ability of limonoids to induce cytotoxicity through multiple pathways. The results of this study provided, for the first time, an evidence of the cytotoxicity of obacunone and OG in androgen-dependent human prostate cancer cells

  12. Analysis of the Effects of Cell Stress and Cytotoxicity on In Vitro Assay Activity Across a Diverse Chemical and Assay Space

    Science.gov (United States)

    Chemical toxicity can arise from disruption of specific biomolecular functions or through more generalized cell stress and cytotoxicity-mediated processes. Here, concentration-dependent responses of 1063 chemicals including pharmaceuticals, natural products, pesticidals, consumer...

  13. Tumour-specific cytotoxicity and structure-activity relationships of novel 1-[3-(2-methoxyethylthio)propionyl]-3,5-bis(benzylidene)-4-piperidones.

    Science.gov (United States)

    Hossain, Mohammad; Das, Umashankar; Umemura, Naoki; Sakagami, Hiroshi; Balzarini, Jan; De Clercq, Erik; Kawase, Masami; Dimmock, Jonathan R

    2016-05-15

    A series of 1-acyl-3,5-bis(benzylidene)-4-piperidones 3-7 were designed and synthesized as novel cytotoxic agents. These compounds displayed potent cytotoxic properties towards human Molt4/C8, CEM, HSC-2, HSC-3 and HSC-4 neoplasms and also to murine L1210 cells. The majority of the compounds have sub-micromolar or very low micromolar IC50 and CC50 values and are significantly more potent than the reference alkylating drug melphalan. Evaluation of these compounds against non-malignant HGF and HPLF cells revealed the tumour-specific toxicity. In particular, 3e emerged as a promising lead cytotoxic agent which caused apoptosis and PARP1 cleavage in HSC-2 cells. PMID:27073056

  14. Protection from Ebola Virus Mediated by Cytotoxic T Lymphocytes Specific for the Viral Nucleoprotein

    OpenAIRE

    Wilson, Julie A.; Hart, Mary Kate

    2001-01-01

    Cytotoxic T lymphocytes (CTLs) are proposed to be critical for protection from intracellular pathogens such as Ebola virus. However, there have been no demonstrations that protection against Ebola virus is mediated by Ebola virus-specific CTLs. Here, we report that C57BL/6 mice vaccinated with Venezuelan equine encephalitis virus replicons encoding the Ebola virus nucleoprotein (NP) survived lethal challenge with Ebola virus. Vaccination induced both antibodies to the NP and a major histocomp...

  15. Intrasinusoidal cytotoxic CD8+ T cells in nodular regenerative hyperplasia of the liver.

    Science.gov (United States)

    Ziol, Marianne; Poirel, Helene; Kountchou, Gisele N; Boyer, Olivier; Mohand, Djamila; Mouthon, Luc; Tepper, Maryline; Guillet, Jean-Gerard; Guettier, Catherine; Raphael, Martine; Beaugrand, Michel

    2004-10-01

    Diffuse nodular regenerative hyperplasia (NRH) of the liver is an acquired architectural disturbance that can lead to portal hypertension. Although frequently associated with autoimmune or hematologic malignancies, its exact pathogenesis remains largely unknown. We observed CD8+ cytotoxic T cells in the liver sinusoids of 14 of 44 NRH patients and explored possible relationships between these lymphocytes and vascular damage. The immunophenotype of intrahepatic lymphocytes was determined using immunohistochemical analysis and endothelial injury using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method for apoptosis combined with endothelial cell labeling. Controls for the quantitative analysis of liver-infiltrating lymphocytes consisted of patients with chronic hepatitis C or normal liver (n = 13 and n = 6, respectively). Liver specimens from the 14 patients dislayed intrasinusoidal infiltrate composed of CD3+ and CD8+ lymphocytes, located near atrophic liver cell plates. Significantly more granzyme B+ and CD57+ lymphocytes were observed in NRH than chronic hepatitis C samples with quantitatively similar CD8+ infiltrates. Double-labeling revealed apoptotic endothelial sinusoidal cells in CD8+ T-cell-infiltrated areas in all NRH samples but never in chronic hepatitis C or normal livers. T-cell receptor rearrangement or immunoscope analysis suggested liver-specific polyclonal or oligoclonal T-cell expansions. Clinical and biological characteristics of the 14 patients were similar to those observed in the 30 patients with NRH devoid of lymphocytic infiltration. We report here that CD8+ cytotoxic T cells infiltrated the liver sinusoids of a high percentage (32%) of NRH patients and suggest that some NRH cases might result from chronic, cytotoxic CD8+ T-lymphocyte targeting of sinusoidal endothelial cells. PMID:15492992

  16. Cytotoxic activity of marine algae against cancerous cells

    Directory of Open Access Journals (Sweden)

    Élica A. C. Guedes

    2013-08-01

    Full Text Available This paper presents an investigation on the cytotoxic activity in human tumor cell from dichloromethane, chloroform, methanol, ethanol, water extracts, and hexane and chloroform fractions from green, brown and red algae collected at Riacho Doce Beach, north coast of Alagoas, Brazil, against the cancer cells K562 (chronic myelocytic leukemia, HEp-2 (laryngeal epidermoid carcinoma and NCI-H292 (human lung mucoepidermoid carcinoma through the MTT colorimetric method. The dichloromethane extract and chloroform fraction of Hypnea musciformis showed the best cytotoxic activity against K562 (3.8±0.2 µg.mL-1 and 6.4±0.4 µg.mL-1, respectively. Dichloromethane extracts of Dictyota dichotoma (16.3±0.3 µg.mL-1 and the chloroform fraction of H. musciformis (6.0±0.03 µg.mL-1 and chloroform fraction of P. gymnospora (8.2±0.4 were more active against HEp-2 as well as ethanol extracts of P. gymnospora (15.9±2.8 µg.mL-1 and chloroform fraction of H. musciformis (15.0±1.3 µg.mL-1 against the cell NCI-H292. The constituents with higher anticancer action are present in the extracts of dichloromethane and chloroform and in the chloroform fraction of H. musciformis, Digenea simplex, P. gymnospora, and D.dichotoma. In the case of the seaweed S. vulgare, the anticancer constituents are present in the aqueous extract.

  17. IN VITRO CYTOTOXICITY OF MADHUCA INDICA AGAINST DIFFERENT HUMAN CANCER CELL LINES

    OpenAIRE

    Satish K. Verma et al.

    2012-01-01

    Cancer is a public health problem all over the world. Large number of plants and their isolated constituents has been shown to potential anticancer activity. Ethanolic whole plant extract of Madhuca indica showed in vitro cytotoxicity against different human cancer cell lines such as lung, neuroblastima, and colon. There was no growth of inhibition recorded against liver cancer cell line. Sulforhodamine B dye (SRB) assay was done for in vitro cytotoxicity test assay. The in vitro cytotoxicity...

  18. New cytotoxic benzo(b)thiophenilsulfonamide 1,1-dioxide derivatives inhibit a NADH oxidase located in plasma membranes of tumour cells

    OpenAIRE

    Alonso, M M; I. Encío; Martínez-Merino, V; M. Gil; Migliaccio, M.

    2001-01-01

    A series of benzo(b)thiophenesulfonamide 1,1-dioxide derivatives (BTS) have been designed and synthesized as candidate antineoplastic drugs. Several of these compounds have shown in vitro cytotoxic activity on leukaemic CCRF-CEM cells. The cytotoxic BTS, but not the inactive ones, were able to inhibit a tumour cell-specific NADH oxidase activity present in the membrane of CCRF-CEM cells. © 2001 Cancer Research Campaign

  19. PDMS/glass microfluidic cell culture system for cytotoxicity tests and cells passage

    DEFF Research Database (Denmark)

    Ziolkowska, K.; Jedrych, E.; Kwapiszewski, R.; Lopacinska, Joanna M.; Skolimowski, Maciej; Chudy, M.

    2010-01-01

    In this paper, hybrid (PDMS/glass) microfluidic cell culture system (MCCS) integrated with the concentration gradient generator (CGG) is presented. PDMS gas permeability enabled cells' respiration in the fabricated microdevices and excellent glass hydrophilicity allowed successful cells' seeding....... The human lung carcinoma cells (A549) were cultured in the microdevice for several days. The growth and proliferation of cells was monitored using an inverted fluorescence microscope. After the cells' confluence was achieved in the microchambers, the novel method of cells' passaging in the designed...... microdevice was developed and successfully tested. The MCCS microdevice is fully reusable, i.e. it can be used several times for various cell culture and cytotoxic experiments. The suitability of designed MCCS for cell-based cytotoxicity assay application was verified using 1,4-dioxane as a model toxic agent...

  20. Cytotoxicity of bovine and porcine collagen membranes in mononuclear cells.

    Science.gov (United States)

    Moura, Camilla Christian Gomes; Soares, Priscilla Barbosa Ferreira; Carneiro, Karine Fernandes; Souza, Maria Aparecida de; Magalhães, Denildo

    2012-01-01

    This study compared the cytotoxicity and the release of nitric oxide induced by collagen membranes in human mononuclear cells. Peripheral blood was collected from each patient and the separation of mononuclear cells was performed by Ficoll. Then, 2x10(5) cells were plated in 48-well culture plates under the membranes in triplicate. The polystyrene surface was used as negative control. Cell viability was assessed by measuring mitochondrial activity (MTT) at 4, 12 and 24 h, with dosage levels of nitrite by the Griess method for the same periods. Data had non-normal distribution and were analyzed by the Kruskal-Wallis test (p<0.05). Statistically significant differences (p<0.05) were observed between the membranes and the control in the experimental period, although there was a significant reduction in viability over time (p<0.01). At 4 and 12 h, the porcine membrane induced a higher release of nitrite compared with the control and bovine membrane, respectively (p<0.01), and this difference was maintained at 24 h (p<0.05). This in vitro study showed that the porcine collagen membrane induces an increased production of proinflammatory mediators by mononuclear cells in the first hours of contact, decreasing with time. PMID:22460313

  1. GM-CSF: modulation of biochemical and cytotoxic effects of tiazofurin in HL-60 cells.

    Science.gov (United States)

    Fritzer, M; Gharehbaghi, K; Pillwein, K; Chiba, P; Goldenberg, H; Szekeres, T

    1993-07-01

    Cytokines, such as granulocyte macrophage colony stimulating factor (GM-CSF) or interleukin-3 (IL-3) recruit quiescent cells into the cell cycle and sensitize these cells towards cell cycle specific chemotherapeutic agents. We examined the in vitro effects of GM-CSF on HL-60 cells and tested its modulatory influence on biochemical and cytotoxic effects seen with tiazofurin, a potent and specific inhibitor of IMP dehydrogenase. Incubation of HL-60 cells with 500 U/ml GM-CSF for 4 d enhanced cell proliferation, which was accompanied by a significant increase in IMP dehydrogenase activity (from 2.22 in control cells to 3.70 nmol/mg/h in cells pretreated with GM-CSF). When HL-60 cells were incubated with 100 microM tiazofurin for 2 h, intracellular GTP decreased to 46% of untreated control cells. In HL-60 cells pretreated with GM-CSF, GTP pools decreased to 38% of control after incubation with tiazofurin which is 69% of the predicted value for additive effect. The MTT chemosensitivity assay yielded significantly decreased IC50 values for tiazofurin in HL-60 cells, preincubated with GM-CSF (IC50 decreased from 13 microM to 10 microM). Therefore our results suggest that combination therapy with GM-CSF and tiazofurin may be beneficial for the treatment of refractory leukaemia patients. PMID:8105873

  2. Developmental cell death programs license cytotoxic cells to eliminate histocompatible partners.

    Science.gov (United States)

    Corey, Daniel M; Rosental, Benyamin; Kowarsky, Mark; Sinha, Rahul; Ishizuka, Katherine J; Palmeri, Karla J; Quake, Stephen R; Voskoboynik, Ayelet; Weissman, Irving L

    2016-06-01

    In a primitive chordate model of natural chimerism, one chimeric partner is often eliminated in a process of allogeneic resorption. Here, we identify the cellular framework underlying loss of tolerance to one partner within a natural Botryllus schlosseri chimera. We show that the principal cell type mediating chimeric partner elimination is a cytotoxic morula cell (MC). Proinflammatory, developmental cell death programs render MCs cytotoxic and, in collaboration with activated phagocytes, eliminate chimeric partners during the "takeover" phase of blastogenic development. Among these genes, the proinflammatory cytokine IL-17 enhances cytotoxicity in allorecognition assays. Cellular transfer of FACS-purified MCs from allogeneic donors into recipients shows that the resorption response can be adoptively acquired. Transfer of 1 × 10(5) allogeneic MCs eliminated 33 of 78 (42%) recipient primary buds and 20 of 76 (20.5%) adult parental adult organisms (zooids) by 14 d whereas transfer of allogeneic cell populations lacking MCs had only minimal effects on recipient colonies. Furthermore, reactivity of transferred cells coincided with the onset of developmental-regulated cell death programs and disproportionately affected developing tissues within a chimera. Among chimeric partner "losers," severe developmental defects were observed in asexually propagating tissues, reflecting a pathologic switch in gene expression in developmental programs. These studies provide evidence that elimination of one partner in a chimera is an immune cell-based rejection that operates within histocompatible pairs and that maximal allogeneic responses involve the coordination of both phagocytic programs and the "arming" of cytotoxic cells. PMID:27217570

  3. Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to γ-irradiation

    International Nuclear Information System (INIS)

    Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to γ-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-γ (rmIFN-γ) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by γ-irradiation. Concomitant priming of γ-irradiated J774 M phi with rmIFN-γ increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC

  4. Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to. gamma. -irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Duerst, R.; Werberig, K. (University of Rochester Medical Center, New York (USA))

    1991-09-01

    Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to {gamma}-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-{gamma} (rmIFN-{gamma}) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by {gamma}-irradiation. Concomitant priming of {gamma}-irradiated J774 M phi with rmIFN-{gamma} increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC.

  5. Adjuvant antiproliferative and cytotoxic effect of aloin in irradiated HeLaS3 cells

    International Nuclear Information System (INIS)

    Naturally occurring phytoanthracycline, aloin, was used to radiosensitize HeLaS3 human cervix carcinoma cells. The results indicated that the cytotoxic adjuvant effect of aloin was synergistic with IR at all drug concentrations and comparable to the cytotoxicity of 5-10Gy IR alone. Radiosensitization of HeLaS3 cells was achieved by 60μM aloin which reduced IC50 dose of IR from 3.4- to 2Gy. The cell damage by both agents compromised cell capacity to conduct programmed cell death by apoptosis, and led to the synergic cytotoxic cell death by necrosis. (author)

  6. Cell-specific precursor processing

    DEFF Research Database (Denmark)

    Rehfeld, Jens F; Bundgaard, Jens R

    2010-01-01

    The singular gene for a peptide hormone is expressed not only in a specific endocrine cell type but also in other endocrine cells as well as in entirely different cells such as neurons, adipocytes, myocytes, immune cells, and cells of the sex-glands. The cellular expression pattern for each gene...... varies with development, time and species. Endocrine regulation is, however, based on the release of a given hormone from an endocrine cell to the general circulation from whose cappilaries the hormone reaches the specific target cell elsewhere in the body. The widespread expression of hormone genes in...... different cells and tissues therefore requires control of biogenesis and secretion in order to avoid interference with the function of a specific hormonal peptide from a particular endocrine cell. Several mechanisms are involved in such control, one of them being cell-specific processing of prohormones. The...

  7. Cytotoxic Effects of Fascaplysin against Small Cell Lung Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Gerhard Hamilton

    2014-03-01

    Full Text Available Fascaplysin, the natural product of a marine sponge, exhibits anticancer activity against a broad range of tumor cells, presumably through interaction with DNA, and/or as a highly selective cyclin-dependent kinase 4 (CDK4 inhibitor. In this study, cytotoxic activity of fascaplysin against a panel of small cell lung cancer (SCLC cell lines and putative synergism with chemotherapeutics was investigated. SCLC responds to first-line chemotherapy with platinum-based drugs/etoposide, but relapses early with topotecan remaining as the single approved therapeutic agent. Fascaplysin was found to show high cytotoxicity against SCLC cells and to induce cell cycle arrest in G1/0 at lower and S-phase at higher concentrations, respectively. The compound generated reactive oxygen species (ROS and induced apoptotic cell death in the chemoresistant NCI-H417 SCLC cell line. Furthermore, fascaplysin revealed marked synergism with the topoisomerase I-directed camptothecin and 10-hydroxy-camptothecin. The Poly(ADP-ribose-Polymerase 1 (PARP1 inhibitor BYK 204165 antagonized the cytotoxic activity of fascaplysin, pointing to the involvement of DNA repair in response to the anticancer activity of the drug. In conclusion, fascaplysin seems to be suitable for treatment of SCLC, based on high cytotoxic activity through multiple routes of action, affecting topoisomerase I, integrity of DNA and generation of ROS.

  8. CHARACTERISTICS OF SIGNALING PATHWAYS MEDIATING A CYTOTOXIC EFFECT OF DENDRITIC CELLS UPON ACTIVATED Т LYMPHOCYTES AND NK CELLS

    Directory of Open Access Journals (Sweden)

    T. V. Tyrinova

    2014-07-01

    Full Text Available Abstract. Cytotoxic/pro-apoptogenic effects of IFNα-induced dendritic cells (IFN-DCs directed against Т-lymphocytes and NK cells were investigated in healthy donors. Using an allogenic MLC system, it was revealed that IFN-DCs induce apoptosis of both activated CD4+ and CD8+ T-lymphocytes, and NK cells. Apoptosis of CD4+ and CD8+ T-lymphocytes induced by their interaction with IFN-DCs was mediated by various signaling pathways. In particular, activated CD4+Т-lymphocytes were most sensitive to TRAIL- и Fas/ FasL-transduction pathways, whereas activated CD8+ T-lymphocytes were induced to apoptosis via TNFα-mediated pathway. PD-1/B7-H1-signaling pathway also played a distinct role in cytotoxic activity of IFNDCs towards both types of T lymphocytes and activated NK cells. The pro-apoptogenic/cytotoxic activity of IFN-DC against activated lymphocytes may be regarded as a mechanism of a feedback regulation aimed at restriction of immune response and maintenance of immune homeostasis. Moreover, upregulation of proapoptogenic molecules on DCs under pathological conditions may lead to suppression of antigen-specific response, thus contributing to the disease progression.

  9. Cytotoxic effects of curcumin in human retinal pigment epithelial cells.

    Directory of Open Access Journals (Sweden)

    Margrit Hollborn

    Full Text Available BACKGROUND: Curcumin from turmeric is an ingredient in curry powders. Due to its antiinflammatory, antioxidant and anticarcinogenic effects, curcumin is a promising drug for the treatment of cancer and retinal diseases. We investigated whether curcumin alters the viability and physiological properties of human retinal pigment epithelial (RPE cells in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Cellular proliferation was investigated with a bromodeoxy-uridine immunoassay, and chemotaxis was investigated with a Boyden chamber assay. Cell viability was determined by trypan blue exclusion. Apoptosis and necrosis rates were determined with a DNA fragmentation ELISA. Gene expression was determined by real-time PCR, and secretion of VEGF and bFGF was examined with ELISA. The phosphorylation level of proteins was revealed by Western blotting. The proliferation of RPE cells was slightly increased by curcumin at 10 µM and strongly reduced by curcumin above 50 µM. Curcumin at 50 µM increased slightly the chemotaxis of the cells. Curcumin reduced the expression and secretion of VEGF under control conditions and abolished the VEGF secretion induced by PDGF and chemical hypoxia. Whereas low concentrations of curcumin stimulated the expression of bFGF and HGF, high concentrations caused downregulation of both factors. Curcumin decreased dose-dependently the viability of RPE cells via induction of early necrosis (above 10 µM and delayed apoptosis (above 1 µM. The cytotoxic effect of curcumin involved activation of caspase-3 and calpain, intracellular calcium signaling, mitochondrial permeability, oxidative stress, increased phosphorylation of p38 MAPK and decreased phosphorylation of Akt protein. CONCLUSION: It is concluded that curcumin at concentrations described to be effective in the treatment of tumor cells and in inhibiting death of retinal neurons (∼10 µM has adverse effects on RPE cells. It is suggested that, during the intake of curcumin as

  10. Increasing a Robust Antigen-Specific Cytotoxic T Lymphocyte Response by FMDV DNA Vaccination with IL-9 Expressing Construct

    Directory of Open Access Journals (Sweden)

    Qiang Zou

    2010-01-01

    Full Text Available Various chemokines and cytokines as adjuvants can be used to improve efficacy of DNA vaccination. In this study, we sought to investigate if a DNA construct expressing IL-9 (designed as proV-IL9 as a molecular adjuvant enhance antigen specific immune responses elicited by the pcD-VP1 DNA vaccination. Mice immunized with pcD-VP1 combined with proV-IL9 developed a strong humoral response. In addition, the coinoculation induced significant higher level of antigen-specific cell proliferation and cytotoxic response. This agreed well with higher expression level of IFN-γ and perforin in CD8+ T cells, but not with IL-17 in these T cells. The results indicate that IL-9 induces the development of IFN-γ-producing CD8+ T cells (Tc1, but not the IL-17-producing CD8+ T cells (Tc17. Up-regulated expressions of BCL-2 and BCL-XL were exhibited in these Tc1 cells, suggesting that IL-9 may trigger antiapoptosis mechanism in these cells. Together, these results demonstrated that IL-9 used as molecular adjuvant could enhance the immunogenicity of DNA vaccination, in augmenting humoral and cellular responses and particularly promoting Tc1 activations. Thus, the IL-9 may be utilized as a potent Tc1 adjuvant for DNA vaccines.

  11. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS).

    Science.gov (United States)

    Fallarero, Adyary; Batista-González, Ana E; Hiltunen, Anna K; Liimatainen, Jaana; Karonen, Maarit; Vuorela, Pia M

    2015-01-01

    Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS)-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree) was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract's pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based) assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow. PMID:26569236

  12. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS

    Directory of Open Access Journals (Sweden)

    Adyary Fallarero

    2015-11-01

    Full Text Available Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract’s pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow.

  13. Mycobacterium avium and purified protein derivative-specific cytotoxicity mediated by CD4+ lymphocytes from healthy HIV-seropositive and-seronegative individuals

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1996-01-01

    mycobacteria. Our objective was to investigate the M.tuberculosis-and M. avium-specific cytotoxic capacity of T cells from healthy, bacille Calmette-Guérin-vaccinated, HIV-seropositive individuals. Blood mononuclear cells were obtained from 10 healthy HIV-seropositive and 10 healthy seronegative persons with...... no history of previous or active mycobacterial infection. Antigen-specific killing of macrophages presenting mycobacterial antigens (purified protein derivative or M. avium culture filtrate) was conducted. The phenotype of the killer cells was determined by a fluorescence-activated cell sorter after...

  14. Simultaneous measurement of NK cell cytotoxicity against two target cell lines labelled with fluorescent lanthanide chelates.

    Science.gov (United States)

    Lövgren, J; Blomberg, K

    1994-07-12

    We describe a cytotoxicity assay which permits the simultaneous measurement of natural killer cell activity against two different cell lines. The target cell lines are labelled either with a fluorescent europium chelate or with a fluorescent terbium chelate and cell death is quantified by measuring the chelate release. K-562, Molt4 and Daudi cell lines have been used as targets. The release of the two chelates from the target cells can be detected with the help of time resolved fluorometry. As the measurements are made after background fluorescence has decayed no additional steps are needed to correct for the background from the medium. The assay procedure used for measurement of cytotoxicity against two target cell lines is very similar to the widely used 51Cr release assay. PMID:8034979

  15. Cytotoxic drug sensitivity of Epstein-Barr virus transformed lymphoblastoid B-cells

    Directory of Open Access Journals (Sweden)

    Olah Eva

    2006-11-01

    Full Text Available Abstract Background Epstein-Barr virus (EBV is the causative agent of immunosuppression associated lymphoproliferations such as post-transplant lymphoproliferative disorder (PTLD, AIDS related immunoblastic lymphomas (ARL and immunoblastic lymphomas in X-linked lymphoproliferative syndrome (XLP. The reported overall mortality for PTLD often exceeds 50%. Reducing the immunosuppression in recipients of solid organ transplants (SOT or using highly active antiretroviral therapy in AIDS patients leads to complete remission in 23–50% of the PTLD/ARL cases but will not suffice for recipients of bone marrow grafts. An additional therapeutic alternative is the treatment with anti-CD20 antibodies (Rituximab or EBV-specific cytotoxic T-cells. Chemotherapy is used for the non-responding cases only as the second or third line of treatment. The most frequently used chemotherapy regimens originate from the non-Hodgkin lymphoma protocols and there are no cytotoxic drugs that have been specifically selected against EBV induced lymphoproliferative disorders. Methods As lymphoblastoid cell lines (LCLs are well established in vitro models for PTLD, we have assessed 17 LCLs for cytotoxic drug sensitivity. After three days of incubation, live and dead cells were differentially stained using fluorescent dyes. The precise numbers of live and dead cells were determined using a custom designed automated laser confocal fluorescent microscope. Results Independently of their origin, LCLs showed very similar drug sensitivity patterns against 29 frequently used cytostatic drugs. LCLs were highly sensitive for vincristine, methotrexate, epirubicin and paclitaxel. Conclusion Our data shows that the inclusion of epirubicin and paclitaxel into chemotherapy protocols against PTLD may be justified.

  16. Specific cytotoxic T lymphocyte responses in Chinese HIV/AIDS patients

    Institute of Scientific and Technical Information of China (English)

    尚红; 韩晓旭; 王亚男; 周立平; 张子宁; 姜拥军; 张旻; 于旭

    2004-01-01

    Human immunodeficiency virus type 1 (HIV-1)-specific cytotoxic T lymphocytes (CTL) are considered to play a central role in the immune response against HIV-1. During untreated acute HIV-1 infection, virus-specific CTL activity is associated with the initial decrease in viremia.1 After HIV infection, those individuals with a slow progressive course develop stronger CTL responses than those with typical disease progression.2,3 Restoring HIV-1-specific CTL responses have been considered a key factor in immune reconstitution and vaccine development. Here we present the analysis of HIV-1 Gag-specific CTL responses in 23 Chinese HIV/AIDS cases in order to take the initial steps at identifying the epitopes that dominate the CTL response in Chinese patients.

  17. Rhinovirus infection induces cytotoxicity and delays wound healing in bronchial epithelial cells

    OpenAIRE

    Constantopoulos Andreas G; Skevaki Chrysanthi L; Gourgiotis Dimitrios; Psarras Stelios; Bossios Apostolos; Saxoni-Papageorgiou Photini; Papadopoulos Nikolaos G

    2005-01-01

    Abstract Background Human rhinoviruses (RV), the most common triggers of acute asthma exacerbations, are considered not cytotoxic to the bronchial epithelium. Recent observations, however, have questioned this knowledge. The aim of this study was to evaluate the ability of RV to induce epithelial cytotoxicity and affect epithelial repair in-vitro. Methods Monolayers of BEAS-2B bronchial epithelial cells, seeded at different densities were exposed to RV serotypes 1b, 5, 7, 9, 14, 16. Cytotoxic...

  18. Cytotoxicity against KB and NCI-H187 cell lines of modified flavonoids from Kaempferia parviflora.

    Science.gov (United States)

    Yenjai, Chavi; Wanich, Suchana

    2010-05-01

    Flavones 1-4 isolated from Kaempferia parviflora were used for structural modification. Sixteen flavonoid derivatives, including four new derivatives, were synthesized and evaluated for cytotoxicity against KB and NCI-H187 cell lines. Flavanones 2a-4a demonstrated higher cytotoxic activity than the parent compounds. Cytotoxicity against KB cell line of oxime 1c was about 7 times higher than the ellipticine standard. Interestingly, oximes 1c and 2c exhibited highly potent cytotoxicity against NCI-H187 cell line with IC(50) values of 0.014 and 0.23 microM, respectively. Oximes 4c and 5c showed strong cytotoxicity against NCI-H187 cell line with IC(50) values of 4.04 and 2.32 microM, respectively. PMID:20362442

  19. A Model of Cytotoxic T Antitumor Activation Stimulated by Pulsed Dendritic Cells

    Science.gov (United States)

    Pennisi, Marzio; Pappalardo, Francesco; Chiacchio, Ferdinando; Motta, Santo

    2011-09-01

    We present a preliminary ODE model to sketch the immune response of cytotoxic T cells against cancer through the use of pulsed autologous dendritic cells. The model is partially based on data coming from experiments that are presently in progress in the wet lab of our collaborators, but it can be applied in principle to different tumors. To this end, we show the immune response of cytotoxic T cells stimulated by autologous dendritic cells for different cancers.

  20. Transient activation of human cytomegalovirus lytic gene expression during latency allows cytotoxic T cell killing of latently infected cells.

    Science.gov (United States)

    Krishna, B A; Lau, B; Jackson, S E; Wills, M R; Sinclair, J H; Poole, E

    2016-01-01

    Human cytomegalovirus (HCMV) latency in the myeloid lineage is maintained by repressive histone modifications around the major immediate early promoter (MIEP), which results in inhibition of the lytic viral life cycle. We now show that pharmacological inhibition of histone deacetylases (HDACs) relieves this repression of the MIEP and induces transient expression of the viral lytic immediate early (IE) antigens but, importantly, not full virus reactivation. In turn, these latently infected cells now become targets for IE-specific cytotoxic T cells (CTLs) which are present at high frequency in all normal healthy HCMV positive carriers but would normally be unable to target latent (lytic antigen-negative) cells. This approach of transiently inducing viral lytic gene expression by HDAC inhibition, in otherwise latently infected cells, offers a window of opportunity to target and purge the latent myeloid cell reservoir by making these normally immunologically undetectable cells visible to pre-existing host immune responses to viral lytic antigens. PMID:27091512

  1. Garcinielliptone FC: antiparasitic activity without cytotoxicity to mammalian cells.

    Science.gov (United States)

    Silva, Ana P; Silva, Marcos P; Oliveira, Cristiano G; Monteiro, Daniela C; Pinto, Pedro L; Mendonça, Ronaldo Z; Costa Júnior, Joaquim S; Freitas, Rivelilson M; de Moraes, Josué

    2015-06-01

    Garcinielliptone FC (GFC) is a natural prenylated benzophenone found in the seeds of Platonia insignis Mart. (Clusiaceae), a native Brazilian plant. It has been chemically characterized and it is known that GFC has several biological activities such as antioxidant and vasorelaxant properties. In this study, we report the in vitro effect of GFC against the blood fluke Schistosoma mansoni, the parasite responsible for schistosomiasis mansoni. The anti-S. mansoni activity and cytotoxicity toward mammalian cells were determined for the compound. GFC⩾6.25 μM showed antischistosomal activity and confocal laser scanning microscopy analysis demonstrated several morphological alterations on the tegument of worms, and a correlation between viability and tegumental damage was observed. In addition, at sub-lethal concentrations of GFC (⩽3.125 μM), the number of S. mansoni eggs was reduced. More importantly, GFC exhibited no activity toward mammalian cells and, therefore, there is an appreciable selectivity of this compound against the helminths. In conclusion, these findings indicate the potential of GFC as an antiparasitic agent. PMID:25553916

  2. Murine cellular cytotoxicity to syngeneic and xenogeneic herpes simplex virus-infected cells.

    OpenAIRE

    Kohl, S; Drath, D B; Loo, L S

    1982-01-01

    Cellular cytotoxicity of C57BL/6 adult mice peritoneal cells to xenogeneic (Chang liver) and syngeneic (BL/6-WT3) herpes simplex virus (HSV)-infected cells was analyzed in a 6-h 51Cr release assay. There was no difference in antibody-dependent cellular cytotoxicity to either target. There was no natural killer cytotoxicity to targets with cells from uninfected mice except at very high effector cell ratios. HSV-infected (2 X 10(4) PFU intraperitoneally 1 day previously) mice mediated significa...

  3. Cytotoxicity and mutagenicity of cola and grape flavored soft drinks in bone marrow cells of rodents

    Directory of Open Access Journals (Sweden)

    Elisângela Düsman

    2013-03-01

    Full Text Available Due to the large consumption of soft drinks in Brazil and worldwide in recent years and considering that some of the components present in their composition pose potential risks to human health, the aim of this study was to evaluate the cytotoxic and mutagenic potential of specific cola and grape-flavored soft drink brands. Bone marrow cells of Wistar rats were initially treated by gavage with one single dose of Cola or Grape soft drink, which was next offered ad libitum (instead of water for 24 hours. A negative control treatment was performed by administering one single dose of water and a positive control administering cyclophosphamide intraperitoneally. Statistical analysis showed that the Cola and Grape soft drinks studied were not cytotoxic. However, the Cola soft drink proved mutagenic in this experiment treatment time. Therefore, this study serves as a warning about the consumption of Cola-flavored soft drink and for the need for further subchronic and chronic studies on soft drinks in order to evaluate the long term mutagenic and cytotoxic effects of these substances.

  4. Compound A398, a novel podophyllotoxin analogue: cytotoxicity and induction of apoptosis in human leukemia cells.

    Directory of Open Access Journals (Sweden)

    Alethéia L Silveira

    Full Text Available Despite advances in oncology research, cancer is one of the leading causes of death worldwide. Thus, there is a demand for the development of more selective and effective antitumor agents. This study showed that A398, a novel podophyllotoxin analogue, was cytotoxic to the HT-29, MCF-7, MOLT-4 and HL-60 tumor cell lines, being less active in human peripheral blood mononuclear cells and normal cell lines FGH and IEC-6. Tests using the HepG2 lineage indicated that its metabolites do not contribute to its cytotoxicity. In the HL-60 cells, A398 induced apoptosis in a time and concentration-dependent manner, promoting mitochondrial depolarization, inhibition of Bcl-2, phosphatidylserine exposure, activation of caspases -8, -9 and -3, and DNA fragmentation. The production of reactive oxygen species does not seem to be a crucial event for the apoptotic process. Pretreatment with specific inhibitors of kinases ERK1/2, JNK and p38 resulted in an increased percentage of death induced by A398. These results indicate that the compound induced apoptosis through activation of intrinsic and extrinsic death pathways with the mechanism involving the inhibition of the MAPKs and Bcl-2. Taken together, our findings suggest that A398 has an anticancer potential, proving itself to be a candidate for preclinical studies.

  5. PMA synergistically enhances apicularen A-induced cytotoxicity by disrupting microtubule networks in HeLa cells

    International Nuclear Information System (INIS)

    Combination therapy is key to improving cancer treatment efficacy. Phorbol 12-myristate 13-acetate (PMA), a well-known PKC activator, increases the cytotoxicity of several anticancer drugs. Apicularen A induces cytotoxicity in tumor cells through disrupting microtubule networks by tubulin down-regulation. In this study, we examined whether PMA increases apicularen A-induced cytotoxicity in HeLa cells. Cell viability was examined by thiazolyl blue tetrazolium (MTT) assays. To investigate apoptotic potential of apicularen A, DNA fragmentation assays were performed followed by extracting genomic DNA, and caspase-3 activity assays were performed by fluorescence assays using fluorogenic substrate. The cell cycle distribution induced by combination with PMA and apicularen A was examined by flow cytometry after staining with propidium iodide (PI). The expression levels of target proteins were measured by Western blotting analysis using specific antibodies, and α-tubulin mRNA levels were assessed by reverse transcription polymerase chain reaction (RT-PCR). To examine the effect of combination of PMA and apicularen A on the microtubule architecture, α-tubulin protein and nuclei were visualized by immunofluorescence staining using an anti-α-tubulin antibody and PI, respectively. We found that apicularen A induced caspase-dependent apoptosis in HeLa cells. PMA synergistically increased cytotoxicity and apoptotic sub-G1 population induced by apicularen A. These effects were completely blocked by the PKC inhibitors Ro31-8220 and Go6983, while caspase inhibition by Z-VAD-fmk did not prevent cytotoxicity. RNA interference using siRNA against PKCα, but not PKCβ and PKCγ, inhibited cytotoxicity induced by combination PMA and apicularen A. PMA increased the apicularen A-induced disruption of microtubule networks by further decreasing α- and β-tubulin protein levels in a PKC-dependent manner. These results suggest that the synergy between PMA and apicularen A is involved by

  6. METHYLCELLULOSE CELL-CULTURE AS A NEW CYTOTOXICITY TEST SYSTEM FOR BIOMATERIALS

    NARCIS (Netherlands)

    VANLUYN, MJA; VANWACHEM, PB; NIEUWENHUIS, P; DAMINK, LO; TENHOOPEN, H; FEIJEN, J

    1991-01-01

    The cytotoxicity of biomaterials can be tested in vitro using various culture systems. Liquid culture systems may detect cytotoxicity of a material either by culture of cells with extracts or with the material itself. In the latter instance, renewing the medium will remove possible released cytotoxi

  7. Effector cell mediated cytotoxicity measured by intracellular Granzyme B release in HIV infected subjects

    Directory of Open Access Journals (Sweden)

    Mahajan Supriya D.

    2003-01-01

    Full Text Available CD8+ cytotoxic T lymphocyte (CTL activity is currently believed to be one of the key immunologic mechanisms responsible for the prevention or attenuation of HIV-1 infection. The induction of CD8+ T cell activation may also result in the production of soluble or non-classical lytic factors that are associated with protection from infection or slower disease progression. Traditionally, CD8+ CTL responses have been measured by the classic chromium release assay, monitoring the ability of T cells (Effector cells to lyse radiolabelled HLA – matched “target cells” that express the appropriate antigen-MHC complex. This method is not only labor intensive, semi quantitative assay at best, but also needs fresh, non-cryopreserved cells. Recently, cytokine specific ELISPOT assays or tetrameric MHC-I/ peptide complexes have utilized to directly quantitate circulating CD8+ effector cells, and these assays are more sensitive, quantitative and reproducible than the traditional CTL lysis assay and can also be performed on cryopreserved cells. Although these are reproducible assays for the assessment of soluble antiviral activity secreted by activated T cell populations they can be extremely expensive to perform. We have used FACS Analysis to measure Granzyme B release as a function of cell mediated cytotoxicity. This method helps quantitate the CTL activity and also identifies the phenotype of the cells elucidating this immune response. The method described not only monitors immunological response but also is also simple to perform, precise and extremely time efficient and is ideal for screening a large number of samples.

  8. Cytotoxic T cell responses to human telomerase reverse transcriptase in patients with hepatocellular carcinoma.

    Science.gov (United States)

    Mizukoshi, Eishiro; Nakamoto, Yasunari; Marukawa, Yohei; Arai, Kuniaki; Yamashita, Tatsuya; Tsuji, Hirokazu; Kuzushima, Kiyotaka; Takiguchi, Masafumi; Kaneko, Shuichi

    2006-06-01

    Human telomerase reverse transcriptase, hTERT, has been identified as the catalytic enzyme required for telomere elongation. hTERT is expressed in most tumor cells but seldom expressed in most human adult cells. It has been reported that 80% to 90% of hepatocellular carcinomas (HCCs) express hTERT, making the enzyme a potential target in immunotherapy for HCC. In the current study, we identified hTERT-derived, HLA-A*2402-restricted cytotoxic T cell (CTL) epitopes and analyzed hTERT-specific CTL responses in patients with HCC. Peptides containing the epitopes showed high affinity to bind HLA-A*2402 in a major histocompatibility complex binding assay and were able to induce hTERT-specific CTLs in both hTERT cDNA-immunized HLA-A*2402/Kb transgenic mice and patients with HCC. The CTLs were able to kill hepatoma cell lines depending on hTERT expression levels in an HLA-A*2402-restricted manner and induced irrespective of hepatitis viral infection. The number of single hTERT epitope-specific T cells detected by ELISPOT assay was 10 to 100 specific cells per 3 x 10(5) PBMCs, and positive T cell responses were observed in 6.9% to 12.5% of HCC patients. hTERT-specific T cell responses were observed even in the patients with early stages of HCC. The frequency of hTERT/tetramer+ CD8+ T cells in the tumor tissue of patients with HCC was quite high, and they were functional. In conclusion, these results suggest that hTERT is an attractive target for T-cell-based immunotherapy for HCC, and the identified hTERT epitopes may be valuable both for immunotherapy and for analyzing host immune responses to HCC. PMID:16729333

  9. Cytotoxic activity of interferon alpha induced dendritic cells as a biomarker of glioblastoma

    Science.gov (United States)

    Mishinov, S. V.; Stupak, V. V.; Tyrinova, T. V.; Leplina, O. Yu.; Ostanin, A. A.; Chernykh, E. R.

    2016-08-01

    Dendritic cells (DCs) are the most potent antigen presenting cells that can play direct role in anti-tumor immune response as killer cells. DC tumoricidal activity can be stimulated greatly by type I IFN (IFNα and IFNβ). In the present study, we examined cytostatic and cytotoxic activity of monocyte-derived IFNα-induced DCs generated from patients with brain glioma and evaluated the potential use of these parameters in diagnostics of high-grade gliomas. Herein, we demonstrated that patient DCs do not possess the ability to inhibit the growth of tumor HEp-2 cell line but low-grade and high-grade glioma patients do not differ significantly in DC cytostatic activity. However, glioma patient DCs are characterized by reduced cytotoxic activity against HEp-2 cells. The impairment of DC cytotoxic function is observed mainly in glioblastoma patients. The cytotoxic activity of DCs against HEp-2 cells below 9% is an informative marker for glioblastomas.

  10. Limited transplantation of antigen-expressing hematopoietic stem cells induces long-lasting cytotoxic T cell responses.

    Directory of Open Access Journals (Sweden)

    Warren L Denning

    Full Text Available Harnessing the ability of cytotoxic T lymphocytes (CTLs to recognize and eradicate tumor or pathogen-infected cells is a critical goal of modern immune-based therapies. Although multiple immunization strategies efficiently induce high levels of antigen-specific CTLs, the initial increase is typically followed by a rapid contraction phase resulting in a sharp decline in the frequency of functional CTLs. We describe a novel approach to immunotherapy based on a transplantation of low numbers of antigen-expressing hematopoietic stem cells (HSCs following nonmyeloablative or partially myeloablative conditioning. Continuous antigen presentation by a limited number of differentiated transgenic hematopoietic cells results in an induction and prolonged maintenance of fully functional effector T cell responses in a mouse model. Recipient animals display high levels of antigen-specific CTLs four months following transplantation in contrast to dendritic cell-immunized animals in which the response typically declines at 4-6 weeks post-immunization. Majority of HSC-induced antigen-specific CD8+ T cells display central memory phenotype, efficiently kill target cells in vivo, and protect recipients against tumor growth in a preventive setting. Furthermore, we confirm previously published observation that high level engraftment of antigen-expressing HSCs following myeloablative conditioning results in tolerance and an absence of specific cytotoxic activity in vivo. In conclusion, the data presented here supports potential application of immunization by limited transplantation of antigen-expressing HSCs for the prevention and treatment of cancer and therapeutic immunization of chronic infectious diseases such as HIV-1/AIDS.

  11. Neolignans from Nectandra megapotamica (Lauraceae Display in vitro Cytotoxic Activity and Induce Apoptosis in Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Vitor Ponci

    2015-07-01

    Full Text Available Nectandra megapotamica (Spreng. Mez. (Lauraceae is a well-known Brazilian medicinal plant that has been used in folk medicine to treat several diseases. In continuation of our ongoing efforts to discover new bioactive natural products from the Brazilian flora, this study describes the identification of cytotoxic compounds from the MeOH extract of N. megapotamica (Lauraceae leaves using bioactivity-guided fractionation. This approach resulted in the isolation and characterization of eight tetrahydrofuran neolignans: calopeptin (1, machilin-G (2, machilin-I (3, aristolignin (4, nectandrin A (5, veraguensin (6, ganschisandrin (7, and galgravin (8. Different assays were conducted to evaluate their cytotoxic activities and to determine the possible mechanism(s related to the activity displayed against human leukemia cells. The most active compounds 4, 5 and 8 gave IC50 values of 14.2 ± 0.7, 16.9 ± 0.8 and 16.5 ± 0.8 µg/mL, respectively, against human leukemia (HL-60 tumor cells. Moreover, these compounds induced specific apoptotic hallmarks, such as plasma membrane bleb formation, nuclear DNA condensation, specific chromatin fragmentation, phosphatidyl-serine exposure on the external leaflet of the plasma membrane, cleavage of PARP as well as mitochondrial damage, which as a whole could be related to the intrinsic apoptotic pathway.

  12. Dual Requirement of Cytokine and Activation Receptor Triggering for Cytotoxic Control of Murine Cytomegalovirus by NK Cells

    Science.gov (United States)

    Pak-Wittel, Melissa A.; Yang, Liping; Schreiber, Robert D.; Yokoyama, Wayne M.

    2015-01-01

    Natural killer (NK) cells play a critical role in controlling murine cytomegalovirus (MCMV) and can mediate both cytokine production and direct cytotoxicity. The NK cell activation receptor, Ly49H, is responsible for genetic resistance to MCMV in C57BL/6 mice. Recognition of the viral m157 protein by Ly49H is sufficient for effective control of MCMV infection. Additionally, during the host response to infection, distinct immune and non-immune cells elaborate a variety of pleiotropic cytokines which have the potential to impact viral pathogenesis, NK cells, and other immune functions, both directly and indirectly. While the effects of various immune deficiencies have been examined for general antiviral phenotypes, their direct effects on Ly49H-dependent MCMV control are poorly understood. To specifically interrogate Ly49H-dependent functions, herein we employed an in vivo viral competition approach to show Ly49H-dependent MCMV control is specifically mediated through cytotoxicity but not IFNγ production. Whereas m157 induced Ly49H-dependent degranulation, efficient cytotoxicity also required either IL-12 or type I interferon (IFN-I) which acted directly on NK cells to produce granzyme B. These studies demonstrate that both of these distinct NK cell-intrinsic mechanisms are integrated for optimal viral control by NK cells. PMID:26720279

  13. Effects of Ginkgo biloba extract on cell proliferation and cytotoxicity in human hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Jane CJ Chao; Chia Chou Chu

    2004-01-01

    AIM: To study the effect of Ginkgo biloba extract (EGb 761)containing 22-27% fiavonoids (ginkgo-flavone glycosides)and 5-7% terpenoids (ginkgolides and bilobalides) on cell proliferation and cytotoxicity in human hepatocellular carcinoma (HCC) cells.METHODS: Human HCC cell lines (HepG2 and Hep3B) were incubated with various concentrations (0-1 000 mg/L) of EGb 761 solution. After 24 h incubation, cell proliferation and cytotoxicity were determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and lactate dehydrogenase (LDH)release, respectively. After 48 h incubation, the expression of proliferating cell nuclear antigen (PCNA) and p53 protein was measured by Western blotting.RESULTS: The results showed that EGb 761 (50-1 000 mg/L)significantly suppressed cell proliferation and increased LDH release (P<0.05) in HepG2 and Hep3B cells compared with the control group. The cell proliferation of HepG2 and Hep3B cells treated with EGb 761 (1 000 mg/L) was 45% and 39% of the control group (P<0.05), respectively. LDH release of HepG2 cells without and with EGb 761 (1 000 mg/L) treatment was 6.7% and 37.7%, respectively, and that of Hep3B cells without and with EGb 761 (1 000 mg/L) treatment was 7.2% and 40.3%, respectively. The expression of PCNA and p53 protein in HepG2 cells treated with EGb 761 (1 000 mg/L)was 85% and 174% of the control group, respectively.CONCLUSION: Ginkgobilobaextract significantly can suppress proliferation and increase cytotoxicity in HepG2 and Hep3B cells. Additionally, Ginkgo biloba extract can decrease PCNA and increase p53 expression in HepG2 cells.

  14. Therapeutic potential of highly cytotoxic natural killer cells for gastric cancer.

    Science.gov (United States)

    Mimura, Kousaku; Kamiya, Takahiro; Shiraishi, Kensuke; Kua, Ley-Fang; Shabbir, Asim; So, Jimmy; Yong, Wei-Peng; Suzuki, Yoshiyuki; Yoshimoto, Yuya; Nakano, Takashi; Fujii, Hideki; Campana, Dario; Kono, Koji

    2014-09-15

    To develop more effective therapies for patients with advanced gastric cancer, we examined the potential of ex vivo expanded natural killer (NK) cells. We assessed the expression of ligands for NK Group 2 Member D (NKG2D, an important NK activation molecule) in primary tumors from 102 patients with gastric cancer by immunohistochemistry and determined their prognostic value. We then examined the in vitro and in vivo cytotoxicity of NK cells from healthy donors and patients with gastric cancer. The cytotoxicity of resting and of interleukin (IL)-2-activated NK cells was compared to that of NK cells expanded for 7 days by coculture with the K562-mb15-4.1BBL cell line. As a result, the expression of NKG2D ligands in primary tumors was correlated with favorable presenting features and outcomes, suggesting that gastric cancer may be sensitive to NK cell cytotoxicity. Although resting NK cells showed minimal cytotoxicity against gastric cancer cells, K562-mb15-4.1BBL-expanded NK cells were highly cytotoxic and significantly more powerful than IL-2-activated NK cells. Cytotoxicity was correlated with NKG2D ligand expression and could be modulated by mitogen-activated protein kinase and AKT-PI3 kinase inhibitors. The cytotoxicity of expanded NK cells against HER2-positive gastric cancer cells could be increased by Herceptin and further augmented by Lapatinib. Finally, expanded NK cells exhibited strong antitumor activity in immunodeficient mice engrafted with a gastric cancer cell line. In conclusion, gastric cancer tumors express NKG2D ligands and are highly susceptible to killing by NK cells stimulated by K562-mb15-4.1BBL. These results provide a strong rationale for clinical testing of these NK cells in patients and suggest their use to augment the effects of antibody therapy. PMID:24615495

  15. Chemosensitizing and cytotoxic effects of 2-deoxy-D-glucose on breast cancer cells

    Directory of Open Access Journals (Sweden)

    Zhang Fanjie

    2009-09-01

    Full Text Available Background: Accelerated glucose uptake for anerobic glycolysis is one of the major metabolic changes found in malignant cells. This property has been exploited for imaging malignancies and as a possible anticancer therapy. The nonmetabolizable glucose analog 2-deoxyglucose (2 DG interferes with glucose metabolism leading to breast cancer cell death. Aims: To determine whether 2DG can synergize with chemotherapeutic agents commonly used in breast cancer treatment and identify cellular characteristics associated with sensitivity to 2DG. Materials and Methods: SkBr3 breast cancer cells were incubated with varying concentrations of 5-fluorouracil (5FU, doxorubicin, cisplatin, cyclophosphamide, or herceptin with or without 2DG. Cell viability was measured using the MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Results: Combining 2DG with doxorubicin, 5 FU, cyclophosphamide, and herceptin resulted in enhanced cell death compared with each agent alone, while in combination with cisplatin, the amount of cell death was additive. Mouse embryo fibroblasts (MEF mutated for p53 (-/- were 30% more sensitive to the cytotoxic effects of 2DG than the parental cell lines. Cells mutated for Bax/Bac, genes involved in protection from apoptosis, are slightly more sensitive than the parental cell lines. Conclusions: These results indicate that 2DG acts synergistically with specific chemotherapeutic agents in causing cell death and the class of chemicals most sensitive appear to be those which cause DNA damage.

  16. Effects of glutathione depletion using buthionine sulphoximine on the cytotoxicity in mammalian cells and human tumor cells in vitro

    International Nuclear Information System (INIS)

    An inhibitor of glutathione biosynthesis, buthionine sulphoximine (BSO), was used to deplete the endogenous thiols in mammalian cells in vitro. In this study, the cytotoxicity of BSO and BSO combined with the hypoxic cell radiosensitizer misonidazole (MISO) was investigated. Both aerobic and hypoxic cytotoxicity of MISO was found to be increased. The concentration of BSO required to reduce the colony forming ability to 50% (Cc) for the chronic cytotoxicity on V79 cells was 0.03 mmol/L under aerobic condition, while the Cc for the acute cytotoxicity on V79 cells under hypoxic and aerobic conditions was 0.4 and 0.5 mmol/L. The growth inhibition rate of human tumor cells K562 and SGC-7901 by BSO wa 6.89-26.06% and 12.01-55.69%, respectively. Enhanced cytotoxic activity was observed when BSO was used in combination with cis-dichlorodiamino Pt(II) or 5-fluorouracil

  17. Effect of mature dendritic cells primed with autologous tumor antigens, patients with epithelial ovarian cancer to stimulate the cytotoxic activity of mononuclear cells in vitro.

    OpenAIRE

    Irina Obleuhova

    2013-01-01

    Along with conservative treatment of epithelial ovarian carcinoma, which has the highest frequency of occurrence of gynecological cancers, specific immunotherapy is a modern and advanced way of treating the disease. Special role in the immunotherapy vaccine therapy is based on dendritic cells (DC). Therefore, the purpose of this study was to assess the effectiveness of the modulation of cytotoxic activity in vitro (in a culture of mononuclear cells) using autologous dendritic cells and tumor ...

  18. Assessment of human natural killer and lymphokine-activated killer cell cytotoxicity against Toxoplasma gondii trophozoites and brain cysts

    International Nuclear Information System (INIS)

    Because previous work has suggested that NK cells may be important in host resistance against the intracellular parasite Toxoplasma gondii we examined whether human NK cells and lymphokine-activated killer (LAK) cells have activity against trophozoites and cysts of this organism in vitro. A method to radiolabel Toxoplasma trophozoites with 51Cr was developed and direct cytotoxic activity was determined by using modifications of the standard 51Cr release assay. Viability of 51Cr-labeled trophozoites assessed by both methylene blue staining and trypan blue exclusion was greater than 90%. Significantly more 51Cr was released by anti-Toxoplasma antibody and C than by antibody in the absence of C. Incubation of trophozoites with freshly isolated human NK cells or NK cells activated with either rIL-2 or rIFN-alpha did not result in significant release of 51Cr (specific lysis was 0 to 2.3%). In contrast, the average specific lysis of radiolabeled trophozoites by LAK cells was significant. In a series of separate experiments, preincubation of radiolabeled trophozoites with heat-inactivated normal or Toxoplasma antibody-positive human serum increased the cytotoxicity of LAK cells from a mean specific lysis of 15% +/- 4.5 to 39% +/- 8.5, respectively, as assessed by 51Cr release. Because previous work has shown that radioisotope release from parasites may be nonspecific, separate experiments were performed to determine the cytotoxicity of LAK cells against antibody-coated trophozoites by using ethidium bromide-acridine orange staining to assess effector cell damage. LAK cells had a mean specific lysis of 51% against antibody-coated trophozoites by ethidium bromide-acridine orange staining. Preincubation with heat-inactivated Toxoplasma-antibody positive human serum did not increase activity of rIL-2-activated NK cells against 51CR-labeled trophozoites

  19. The study on the induction of specific immune cytotoxic T lymphocyte responses against pancreatic cancer by transfected dendritic cells with common tumor antigen survivin mRNAs in vitro%Survivin mRNA转染树突细胞诱导特异性抗胰腺癌免疫反应的体外研究

    Institute of Scientific and Technical Information of China (English)

    郭晓钟; 陈江

    2011-01-01

    Objective To investigate the induction of specific anti-tumor immune response by transfected dendritic cells (DCs) with survivin mRNA of human pancreatic cancer, and to provide the experimental evidences for the treatment of human pancreatic cancer with DCs vaccine. Methods DCs were isolated and cultured from peripheral blood mononuclear cells (PBMCs). After being transcripted and amplified, survivin mRNA was transfected into DCs by electroporation. The expression of survivin in DCs at different time points was detected by quantitative real-time PCR. The survival rate of DCs before and after transfection was determined by MTT method. The induction of specific cytotoxic T lymphocyte (CTL) response by survivin mRNA transfected DCs was measured by 51Cr standard cytotoxicity test. The induction of specific CTL activation by survivin mRNA transfected DCs was evaluated through testing released IFN-γ by ELISA method. Results After survivin mRNA transfection for 48h, the expression of survivin mRNA in DCs reached the highest point (46.09±6.57). After transfection, the survival rate of DCs was stabilized around 80%. The DCs transfected with survivin mRNA could effectively induce HLA-A2+ / survivin+ specific CTL immune responses. Stimulated with pancreatic cancer cell line Capan-2 cells or SCL-1 cells as control group, the IFN-γ released in 24 hours by survivin specific CTL were (28.79±5.70) U/ml and (25.12±2.13) U/ml respectively, there was no significant difference (P=0.761). Conclusion The induction of CTLs by DCs transfected with human pancreatic cancer survivin mRNA could produce specific anti-tumor immunity.%目的 研究人胰腺癌survivin mRNA转染树突细胞(DC)诱导的特异性抗肿瘤免疫反应,为DC疫苗治疗胰腺癌提供实验依据.方法 自样本外周血单核细胞中分离和培养DC.体外转录和PCR扩增survivin mRNA后使用电穿孔法将其转染DC.采用实时定量PCR技术检测不同时间点DC中survivin的表达.用四甲基

  20. Cytotoxicity testing of materials with limited in vivo exposure is affected by the duration of cell-material contact.

    Science.gov (United States)

    Ciapetti, G; Granchi, D; Stea, S; Savarino, L; Verri, E; Gori, A; Savioli, F; Montanaro, L

    1998-12-15

    Silicones for dental impression largely are used to record the geometry of hard and soft dental tissues. They are considered to be medical devices, and the assessment of cytotoxicity is a necessary step in the evaluation of their biocompatibility. Extracts of six addition-type and six condensation-type silicones have been tested with L929 cells according to the ISO 10993-Part 5 standard. The cytotoxicity was evaluated by three different methods: neutral red uptake, propidium iodide (PI) staining, and amido black staining. According to the selected specific assay, contact between cells and material extracts was maintained for 24 h in the first series of experiments; then, considering that in vivo application of these materials is restricted to a few minutes, additional experiments were performed after 1 h of cell/extract contact. Analysis of the results showed that the addition-type silicones are nontoxic even when tested after prolonged exposure of the cells to the materials while the condensation-type silicones were cytotoxic at 24 h of incubation. Nevertheless, harm to the patient actually could be negligible, considering its very short time of exposure in vivo. This is supported by our finding that most are not toxic after 1 h. We suggest that the experimental conditions of cytotoxicity testing have to be relevant to the in vivo situation; accordingly, the time of exposure should be designed carefully. PMID:9827670

  1. Adjuvant antiproliferative and cytotoxic effect of aloin in irradiated HeLaS3 cells

    Science.gov (United States)

    Nićiforović, A.; Adžić, M.; Zarić, B.; Radojčić, M. B.

    2007-09-01

    Naturally occurring phytoanthracycline, aloin, was used to radiosensitize HeLaS3 human cervix carcinoma cells. The results indicated that the cytotoxic adjuvant effect of aloin was synergistic with gammaionizing radiation at all drug concentrations and comparable to the cytotoxicity of 5-10 Gy ionizing radiation alone. Radiosensitization of HeLaS3 cells was achieved by 60 μM aloin, which reduced the IC50 dose of ionizing radiation from 3.4 to 2 Gy. Ionizing radiation and aloin alone or in combination are shown to cause perturbation of the HeLaS3 cell-cycle and increase the percentage of cells in the DNA synthesis (S) phase of the cell cycle. While either of the agents applied alone causes programmed cell death by apoptosis, the simultaneous cell damage by both agents through the altered redox balance compromised cell capacity to conduct this program and led to synergic cytotoxic cell death by necrosis.

  2. NAD(P)H dehydrogenase, quinone 1 (NQO1), protects melanin-producing cells from cytotoxicity of rhododendrol.

    Science.gov (United States)

    Okubo, Ayaka; Yasuhira, Shinji; Shibazaki, Masahiko; Takahashi, Kazuhiro; Akasaka, Toshihide; Masuda, Tomoyuki; Maesawa, Chihaya

    2016-05-01

    Rhododendrol (RD) is a potent tyrosinase inhibitor that is metabolized to RD-quinone by tyrosinase, which may underlie the cytotoxicity of RD and leukoderma of the skin that may result. We have examined how forced expression of the NAD(P)H quinone dehydrogenase, quinone 1 (NQO1), a major quinone-reducing enzyme in cytosol, affects the survival of RD-treated cells. We found that treatment of the mouse melanoma cell line B16BL6 or normal human melanocytes with carnosic acid, a transcriptional inducer of the NQO1 gene, notably suppressed the cell killing effect of RD. This effect was mostly abolished by ES936, a highly specific NQO1 inhibitor. Moreover, conditional overexpression of the human NQO1 transgene in B16BL6 led to an expression-dependent increase of cell survival after RD treatment. Our results suggest that NQO1 attenuates the cytotoxicity of RD and/or its metabolites. PMID:26847926

  3. Rapid assay system for cytotoxicity tests using 14C-leucine incorporation into tumor cells

    International Nuclear Information System (INIS)

    Cell viability under various conditions of cytotoxicity test was assessed by terminal labeling of tumor cells, T24 cell line derived from urinary bladder carcinoma, with 14C-leucine. Changes of 14C-leucine incorporation into the cells were fairly proportional to those of viable cell number measured by the trypan blue exclusion method, but a definite correlation between the two measurements was not always found following cytotoxic manipulations. When the cells were labeled immediately after drug treatments, 14C-leucine incorporation usually led to fluctuated and insensitive results presumably due to disturbed metabolic activities unrelated to cell viability and failed to indicate the degree of cell damage. It was shown, however, that the cytotoxicity test was satisfactorily determined by labeling tumor cells with 14C-leucine after recovery in fresh medium for 24 hr. Cytotoxic effects of anticancer drugs with concentration- and time-dependency, hyperthermia and phytohemagglutinin-stimulated lymphocytes were demonstrated by the radioactivity incorporated into the target cells on day 2 after removal of the cytotoxic factors. The results indicate that the terminal labeling of tumor cells with 14C-leucine can be used as a rapid and reliable measure sensitivities to cell viability for an in vitro assay system. (author)

  4. Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica Papaya Leaf Extracts

    OpenAIRE

    Thao T. Nguyen; Marie-Odile Parat; Mark P. Hodson; Jenny Pan; Paul N. Shaw; Hewavitharana, Amitha K.

    2015-01-01

    In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high l...

  5. In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines

    Directory of Open Access Journals (Sweden)

    Paula M. Kustiawan

    2014-07-01

    Conclusions: Propolis from T. incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines. Further study is required, including the isolation and characterization of the active antiproliferative agent(s.

  6. Cytotoxic effects of four aescin types on human colon adenocarcinoma cell lines.

    Science.gov (United States)

    Seweryn, Ewa; Gleńsk, Michal; Sroda-Pomianek, Kamila; Ceremuga, Ireneusz; Wlodarczyk, Maciej; Gamian, Andrzej

    2014-03-01

    Four types of aescin that are available on the pharmaceutical market, beta-aescin crystalline, beta-aescin amorphous, beta-aescin sodium and aescin polysulfate, have been analyzed for their cytotoxic effects on human colon adenocarcinoma (LoVo) and doxorubicin-resistant human colon adenocarcinoma cell lines (LoVo/Dx). Their cytotoxic activities were evaluated by sulforhodamine B (SRB) and methyl tetrazolium (MTT) assays. All four types of aescin exerted strong dose-dependent cytotoxicity to LoVo and, to a lesser degree, LoVo/Dx cell lines. The IC50 value for the LoVo/Dx cell line was higher, but still dose-dependent. Results from both assays demonstrated that p-aescin crystalline has the most cytotoxic activity toward human colon adenocarcinoma cell lines. PMID:24689224

  7. Novel Mutation in Syntaxin-Binding Protein 2 (STXBP2) Prevents IL-2-induced Natural Killer Cell Cytotoxicity

    OpenAIRE

    Saltzman, Rushani W.; Monaco-Shawver, Linda; Zhang, Kejian; Sullivan, Kathleen E.; Filipovich, Alexandra H.; Orange, Jordan S.

    2012-01-01

    We have identified dizygotic twins with a novel syntaxin-binding protein 2 (STXBP2) mutation, where cytotoxicity cannot be restored with IL-2. This defines STXBP2 as an absolute requirement for NK cell cytotoxic function.

  8. Streptozotocin-Induced Cytotoxicity, Oxidative Stress and Mitochondrial Dysfunction in Human Hepatoma HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Haider Raza

    2012-05-01

    Full Text Available Streptozotocin (STZ is an antibiotic often used in the treatment of different types of cancers. It is also highly cytotoxic to the pancreatic beta-cells and therefore is commonly used to induce experimental type 1 diabetes in rodents. Resistance towards STZ-induced cytotoxicity in cancer cells has also been reported. Our previous studies have reported organ-specific toxicity and metabolic alterations in STZ-induced diabetic rats. STZ induces oxidative stress and metabolic complications. The precise molecular mechanism of STZ-induced toxicity in different tissues and carcinomas is, however, unclear. We have, therefore, investigated the mechanism of cytotoxicity of STZ in HepG2 hepatoma cells in culture. Cells were treated with different doses of STZ for various time intervals and the cytotoxicity was studied by observing the alterations in oxidative stress, mitochondrial redox and metabolic functions. STZ induced ROS and RNS formation and oxidative stress as measured by an increase in the lipid peroxidation as well as alterations in the GSH-dependent antioxidant metabolism. The mitochondria appear to be a highly sensitive target for STZ toxicity. The mitochondrial membrane potential and enzyme activities were altered in STZ treated cells resulting in the inhibition of ATP synthesis. ROS-sensitive mitochondrial aconitase activity was markedly inhibited suggesting increased oxidative stress in STZ-induced mitochondrial toxicity. These results suggest that STZ-induced cytotoxicity in HepG2 cells is mediated, at least in part, by the increase in ROS/RNS production, oxidative stress and mitochondrial dysfunction. Our study may be significant for better understanding the mechanisms of STZ action in chemotherapy and drug induced toxicity.

  9. Endoplasmic reticulum targeting sequence enhances HBV-specific cytotoxic T lymphocytes induced by a CTL epitope-based DNA vaccine

    International Nuclear Information System (INIS)

    CD8+ T cells play a critical role in protective immunity against Hepatitis B Virus (HBV). Epitope-based DNA vaccines expressing HBV-dominant CTL epitopes can be used as candidate vaccines capable of inducing cytotoxic T Lymphocytes (CTL) responses. A plasmid DNA encoding a CTL epitope of HBV core antigen, HBc18-27, was constructed. Intramuscular immunization of C57BL/6 mice with this DNA vaccine resulted in successful induction of HBV-specific CTL responses. In order to promote transportation of the peptide into endoplasmic reticulum (ER) to bind to MHC class I molecules for optimal class I antigen presentation, an ER targeting sequence (ERTS) was fused with the C18-27 encoding gene. ERTS fusion significantly enhanced specific CD8+ T cell responses in terms of CTL cytolysis as well as IFN-γ secretion. This enhancement was correlated with promoted epitope presentation on target cell surface. We report here an enhanced immunogenicity of an epitope-based DNA vaccine using an ER targeting signal sequence, which has significant implications for future design of therapeutic HBV vaccine

  10. Electrochemical monitoring of phytochelatin accumulation in Nicotiana tabacum cells exposed to sub-cytotoxic and cytotoxic levels of cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Fojta, Miroslav [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic)]. E-mail: fojta@ibp.cz; Fojtova, Miloslava [Laboratory of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Havran, Ludek [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Pivonkova, Hana [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Dorcak, Vlastimil [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Sestakova, Ivana [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, 182 23 Prague 8 (Czech Republic)

    2006-02-03

    Cadmium belongs to the most dangerous environmental pollutants among the toxic heavy metals seriously affecting vital functions in both animal and plant cells. It has been previously shown that cadmium ions at 50-100 {mu}M concentrations caused tobacco BY-2 (TBY-2) cells to enter apoptosis within several days of exposure. Phytochelatins (PCs), the 'plant metallothioneins', are cysteine-rich peptides involved in detoxification of heavy metals in plants. The PCs are synthesized in response to the heavy metal exposure. In this paper, we utilized electrochemical analysis to monitor accumulation of PCs in the TBY-2 cells exposed to cadmium ions. Measurements of a characteristic PC signal at mercury electrode in the presence of cobalt ions made it possible to detect changes in the cellular PC levels during the time of cultivation, starting from 30 min after exposure. Upon TBY-2 cultivation in the presence of cytotoxic cadmium concentrations, the PC levels remarkably increased during the pre-apoptotic phase and reached a limiting value at cultivation times coinciding with apoptosis trigger. The PC level observed for a sub-cytotoxic cadmium concentration (10 {mu}M) was about three-times lower than that observed for the 50 or 100 {mu}M cadmium ions after 5 days of exposure. We show that using a simple electrochemical analysis, synthesis of PCs in plant cells can be easily followed in parallel with other tests of the cellular response to the toxic heavy metal stress.

  11. CYTOTOXICITY AND MODE OF CELL DEATH INDUCED BY TRIPHENYLTIN (IV COMPOUNDS IN VITRO

    Directory of Open Access Journals (Sweden)

    Normah Awang

    2014-01-01

    Full Text Available A series of newly synthesized organotin (IV with N-alkyl-N-phenyldithiocarbamate ligands namely triphenyltin (IV ethylphenyldithiocarbamate (compound 1 and triphenyltin (IV butylphenyldithiocarbamate (compound 2 were assessed for their cytotoxic effect against HT-29 human colon adenocarcinoma cells and human CCD-18Co normal colon cells. The cytotoxicity of these organotins in both cells was assessed using 3-(4,5-dimethylthiazol-2-yl-2, 5-diphenyltetrazholium bromide (MTT assay upon 24 h treatment. Both compounds demonstrated potent cytotoxicity towards HT-29 cells with the IC50 of 0.18 µM for compound 1 and 0.20 µM for compound 2. Interestingly, compound 1 exhibited lower cytotoxicity towards CCD-18Co with IC50 of 1.55 µM whereas no IC50 was detected for compound 2 up to 2 µM treatment. The mode of cell death was determined based on the externalization of phosphatidylserine using flow cytometry. Cells treated with compound 1 and compound 2 were mainly viable and the apoptotic cell death was around 10% which suggests that both compounds induced growth arrest. In conclusion, this study demonstrated that both compounds were selective towards human colorectal cells by giving a strong cytotoxicity to cancer cells and low toxicity towards normal cells. Both compounds were suggested to induce growth arrest in HT-29 cells.

  12. Role of reactive oxygen species in cis-dichlorodiammineplatinum-induced cytotoxicity on bladder cancer cells.

    OpenAIRE

    Miyajima, A; Nakashima, J.; Yoshioka, K; Tachibana, M.; Tazaki, H.; Murai, M

    1997-01-01

    This study was undertaken to investigate the intracellular induction of reactive oxygen species (ROS) by cis-dichlorodiammineplatinum (CDDP) and the augmentation of their cytotoxicity in bladder cancer cells (KU7) by enhancement of ROS generation by the glutathione (GSH) depletors buthionine sulphoximine (BSO) and diethylmaleate (DEM). CDDP-induced cytotoxicity in KU7 cells and its modulation by GSH depletors were determined using spectrophotometric measurement with crystal violet staining. T...

  13. Immunohistochemical localization of granzyme B antigen in cytotoxic cells in human tissues.

    OpenAIRE

    Hameed, A.; Truong, L D; Price, V; Kruhenbuhl, O.; Tschopp, J

    1991-01-01

    Human granzyme B antigen is expressed in cytoplasmic granules of activated cytotoxic T lymphocytes and natural killer cells. Recombinant granzyme B was generated using a prokaryotic expression vector under the control of T7 transcription and translation signals. The 25-kd recombinant protein (granzyme B) was used to develop a rabbit polyclonal antiserum. Purified anti-granzyme B antibodies were used to detect the antigen expression in cytotoxic cells in human tissues. Using the avidin-biotin-...

  14. Modulating microtubule stability enhances the cytotoxic response of cancer cells to paclitaxel

    OpenAIRE

    Ahmed, Ahmed Ashour; Wang, Xiaoyan; Lu, Zhen; Goldsmith, Juliet,; Le, Xiao-Feng; Grandjean, Geoffrey; Bartholomeusz, Geoffrey; Broom, Bradley; Bast, Robert C.

    2011-01-01

    The extracellular matrix protein TGFBI enhances the cytotoxic response of cancer cells to paclitaxel by affecting integrin signals that stabilize microtubules. Extending the implications of this knowledge, we tested the more general hypothesis that cancer cell signals which increase microtubule stability before exposure to paclitaxel may increase its ability to stablize microtubules and thereby enhance its cytotoxicity. Toward this end, we performed an siRNA screen to evaluate how genetic dep...

  15. Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.

    Science.gov (United States)

    Poh, Su Li; Linn, Yeh Ching

    2016-05-01

    We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML. PMID:26961084

  16. Rhinovirus infection induces cytotoxicity and delays wound healing in bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Constantopoulos Andreas G

    2005-10-01

    Full Text Available Abstract Background Human rhinoviruses (RV, the most common triggers of acute asthma exacerbations, are considered not cytotoxic to the bronchial epithelium. Recent observations, however, have questioned this knowledge. The aim of this study was to evaluate the ability of RV to induce epithelial cytotoxicity and affect epithelial repair in-vitro. Methods Monolayers of BEAS-2B bronchial epithelial cells, seeded at different densities were exposed to RV serotypes 1b, 5, 7, 9, 14, 16. Cytotoxicity was assessed chromatometrically. Epithelial monolayers were mechanically wounded, exposed or not to RV and the repopulation of the damaged area was assessed by image analysis. Finally epithelial cell proliferation was assessed by quantitation of proliferating cell nuclear antigen (PCNA by flow cytometry. Results RV1b, RV5, RV7, RV14 and RV16 were able to induce considerable epithelial cytotoxicity, more pronounced in less dense cultures, in a cell-density and dose-dependent manner. RV9 was not cytotoxic. Furthermore, RV infection diminished the self-repair capacity of bronchial epithelial cells and reduced cell proliferation. Conclusion RV-induced epithelial cytotoxicity may become considerable in already compromised epithelium, such as in the case of asthma. The RV-induced impairment on epithelial proliferation and self-repair capacity may contribute to the development of airway remodeling.

  17. DNA fragmentation: manifestation of target cell destruction mediated by cytotoxic T-cell lines, lymphotoxin-secreting helper T-cell clones, and cell-free lymphotoxin-containing supernatant

    International Nuclear Information System (INIS)

    A Lyt-2+, trinitrophenyl-specific, lymphotoxin-secreting, cytotoxic T-cell line, PCl 55, mediates the digestion of target cell DNA into discretely sized fragments. This phenomenon manifests itself within 30 min after effector cell encounter as measured by the release of 3H counts from target cells prelabeled with [3H]deoxythymidine and occurs even at very low effector to target cell ratios (0.25:1). A Lyt-1+, ovalbumin-specific, lymphotoxin-secreting T-helper cell clone, 5.9.24, is also able to mediate fragmentation of target cell DNA over a time course essentially indistinguishable from the cytotoxic T lymphocyte-mediated hit. Cell-free lymphotoxin-containing supernatants also cause release of DNA from targets, although they require a longer time course, on the order of 24 hr. In contrast, lysis of cells by antibody plus complement or Triton X-100 does not result in DNA release even after extended periods of incubation (24 hr). All three treatments that result in the release of DNA from cells cause fragmentation of that DNA into discretely sized pieces that are multiples of 200 base pairs. The results thus suggest that cytotoxic T cells, lymphotoxin-secreting helper clones with cytolytic activity, and lymphotoxin all effect target cell destruction by means of a similar mechanism and that observed differences in time course and the absence of target cell specificity in killing mediated by lymphotoxin may simply reflect differences in the mode of toxin delivery

  18. Cytotoxicity mechanism of α-MMC in normal liver cells through LRP1 mediated endocytosis and JNK activation.

    Science.gov (United States)

    Wang, Ling; Shen, Fubing; Zhang, Min; He, Qianchuan; Zhao, Hui; Yu, Xiaoping; Yang, Shuxia; Liu, Yang; Deng, Nianhua; Zheng, Juecun; Zhu, Lixia; Liu, Xiaolan

    2016-05-16

    Alpha-momorcharin (α-MMC), a type I ribosome-inactivating protein isolated from Momordica charantia, is a potential drug candidate with strong anti-tumor activity. However, α-MMC has a severe hepatotoxicity when applied in vivo, which may greatly hinders its use in clinic in the future. The biological mechanism of hepatotoxicity induced by α-MMC is largely unknown, especially the mechanism by which α-MMC enters the hepatocytes. In this study, we investigated α-MMC-induced cytotoxicity in normal liver L02 cell line as well as the mechanism underlying it. As expected, α-MMC is more toxic in L02 cells than in various normal cells from other organs. The cytotoxic effect of α-MMC on L02 cells is found to be mediated through cell apoptosis as detected by flow cytometry and fluorescence microscopy. Importantly, α-MMC was shown to bind to a specific receptor on cell membrane, as the density of the cell membrane receptor is closely related to both the amount of α-MMC endocytosed and the cytotoxicity in different cell lines. By using LRP1 competitive inhibitor α2-M or siRNA targeting LRP1, we further identified that LRP1 protein served as the membrane receptor for α-MMC. Both α2-M and siRNA targeting LRP1 can significantly inhibit α-MMC's endocytosis as well as its cytotoxicity in L02 cells. In addition, it was found that α-MMC can activate the JNK signalling pathways via LRP1 in L02 cells. As JNK activation often leads to cell apoptosis, the activation of JNK may play an important role in α-MMC-induced cytotoxicity. To our knowledge, this is the first report showing that LRP1 mediates the cytotoxicity of α-MMC through (1) endocytosis and induced apoptosis and (2) the activation of the JNK pathway. Our findings shed light on the fundamental mechanism of hepatotoxicity of α-MMC and offer reference to understand its mechanism of lymphocytotoxicity and neurotoxicity. PMID:27262837

  19. Cytotoxic and apoptotic effects of six herbal plants against the human hepatocarcinoma (HepG2 cell line

    Directory of Open Access Journals (Sweden)

    Nonpunya Apiyada

    2011-10-01

    Full Text Available Abstract Background Six plants from Thailand were evaluated for their cytotoxicity and apoptosis induction in human hepatocarcinoma (HepG2 as compared to normal African green monkey kidney epithelial cell lines. Methods Ethanol-water crude extracts of the six plants were tested with neutral red assay for their cytotoxicity after 24 hours of exposure to the cells. Apoptotic induction was tested in the HepG2 cells with diamidino-2-phenylindole staining. DNA fragmentation, indicative of apoptosis, was analyzed with agarose gel electrophoresis. Alkylation, indicative of DNA damage, was also evaluated in vitro by 4-(4'-nitrobenzyl pyridine assay. Results The extract of Pinus kesiya showed the highest selectivity (selectivity index = 9.6 and potent cytotoxicity in the HepG2 cell line, with an IC50 value of 52.0 ± 5.8 μg/ml (mean ± standard deviation. Extract of Catimbium speciosum exerted cytotoxicity with an IC50 value of 55.7 ± 8.1 μg/ml. Crude extracts from Glochidion daltonii, Cladogynos orientalis, Acorus tatarinowii and Amomum villosum exhibited cytotoxicity with IC50 values ranging 100-500 μg/ml. All crude extracts showed different alkylating abilities in vitro. Extracts of P. kesiya, C. speciosum and C. orientalis caused nuclei morphological changes and DNA laddering. Conclusion The extracts of C. speciosum, C. orientalis and P. kesiya induced apoptosis. Among the three plants, P. kesiya possessed the most robust anticancer activity, with specific selectivity against HepG2 cells.

  20. Endothelial cell cytotoxicity of cotton bracts tannin and aqueous cotton bracts extract

    International Nuclear Information System (INIS)

    Using an in vitro cytotoxicity assay based on the release of 51Cr from cultured porcine thoracic aortic and pulmonary arterial endothelial cells, we have demonstrated that cotton bracts tannin is a potent endothelial cell cytotoxin. It produces dose-dependent lethal injury to both types of endothelial cells with the aortic cells, being somewhat more sensitive to tannin-mediated injury than the pulmonary arterial cells. Cytotoxic injury to the cells was biphasic. During the first 3 hr of exposure to tannin, no lethal injury was detected. However, during this period, profound changes in morphology were observed suggesting sublethal injury to the cells preceded the ultimate toxic damage. Comparison of the cytotoxicity dose curves for aqueous bracts extracts with those for tannin demonstrated that tannin was major cytotoxin present in bracts

  1. Cytotoxicity of methanol extracts of Elaeis guineensis on MCF-7 and Vero cell lines

    Institute of Scientific and Technical Information of China (English)

    Soundararajan; Vijayarathna; Sreenivasan; Sasidharan

    2012-01-01

    Objective:To investigate the cytotoxic effect of Elaeis guineensis methanol extract on MCF-7and Vero cell.Methods:In vitro cytotoxicity was evaluated in by MTT assay.Cell morphological changes were observed by using light microscope.Results:The MTT assay indicated that methanol extract of the plant exhibited significant cytotoxic effects on MCF-7.Morphological alteration of the cell lines after exposure with lilaeis guineensis extract were observed under phase contrast microscope in the dose dependent manner.Conclusions:The results suggest the probable use of the Elaeis guineensis methanol extract in preparing recipes for cancer-related ailments.Further studies on isolation of metabolites and their in vivo cytotoxicity are under investigation.

  2. Synthesis of Chromonylthiazolidines and Their Cytotoxicity to Human Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Hoang Le Tuan Anh

    2015-01-01

    Full Text Available Nine new chromonylthiazolidine derivatives were successfully semi-synthesized from paeonol. All of the compounds, including starting materials, the intermediate compound and products, were evaluated for their cytotoxic effects toward eight human cancer cell lines. The synthesized chromonylthiazolidines displayed weak cytotoxic effects against the tested cancer cell lines, but selective cytotoxic effects were observed. Compounds 3a and 3b showed the most selective cytotoxic effects against human epidermoid carcinoma (IC50 44.1 ± 3.6 μg/mL and breast cancer (IC50 32.8 ± 1.4 μg/mL cell lines, respectively. The results suggest that chromoylthiazolidines are potential low-cost, and selective anticancer agents.

  3. Protein kinase inhibitor-induced endothelial cell cytotoxicity and its prediction based on calculated molecular descriptors.

    Science.gov (United States)

    Herczenik, Eszter; Varga, Zoltán; Eros, Dániel; Makó, Veronika; Oroszlán, Melinda; Rugonfalvi-Kiss, Szabolcs; Romics, László; Füst, George; Kéri, György; Orfi, László; Cervenak, László

    2009-01-01

    Protein kinase inhibitors (PKIs) as potent signal transduction therapeutic compounds represent a very rapidly expanding group of anticancer drugs. These agents may be toxic for endothelial cells, however, very few experimental data exist on the cytotoxicity of PKIs. The aim of this study was to set up an appropriate test system for endothelial cells and to assess the structure-related cytotoxic effects of a selected library of PKIs. The inhibitor library contains several lead molecules with different basic structures and a set of modified derivatives of the lead compounds. The toxicity of PKIs did not correlate directly with the structural features of the molecules. However, we successfully built up a model based on 15 calculated molecular descriptors, which is capable of predicting cytotoxicity with acceptable probability. Our results show that the cytotoxic effects of PKIs should be taken into account for optimal drug development to overcome endothelial cell-related side effects. PMID:19519173

  4. Synergistic cytotoxicity of gemcitabine, clofarabine and edelfosine in lymphoma cell lines

    OpenAIRE

    Valdez, B C; Zander, A R; Song, G.; Murray, D; Nieto, Y; Li, Y.; Champlin, R E; Andersson, B. S.

    2014-01-01

    Treatments for lymphomas include gemcitabine (Gem) and clofarabine (Clo) which inhibit DNA synthesis. To improve their cytotoxicity, we studied their synergism with the alkyl phospholipid edelfosine (Ed). Exposure of the J45.01 and SUP-T1 (T-cell) and the OCI-LY10 (B-cell) lymphoma cell lines to IC10–IC20 levels of the drugs resulted in strong synergistic cytotoxicity for the 3-drug combination based on various assays of cell proliferation and apoptosis. Cell death correlated with increased p...

  5. Cytotoxicity and gene expression changes induced by inorganic and organic trivalent arsenicals in human cells

    International Nuclear Information System (INIS)

    Highlights: • Human urothelial, skin and bronchial epithelial cells treated with trivalent arsenicals. • Determined cytotoxicity (LC50) and gene expression changes. • Each trivlaent had LC50s at similar ranges in all the cell types. • Minor differences in gene expression changes observed between trivalent arsenicals. • Overall trivalent arsenicals induced similar gene changes between the cell types. - Abstract: Inorganic arsenic (iAs) is a human urinary bladder, skin and lung carcinogen. iAs is metabolized to methylated arsenicals, with trivalent arsenicals more cytotoxic than pentavalent forms in vitro. In this study, cytotoxicity and gene expression changes for arsenite (iAsIII), monomethylarsonous acid (MMAIII) and dimethylarsinous acid (DMAIII) were evaluated in three human cell types, urothelial (1T1), keratinocyte (HEK001) and bronchial epithelial (HBE) cells, corresponding to target organs for iAs-induced cancer. Cells were exposed to arsenicals to determine cytotoxicity and to study gene expression changes. Affymetrix chips were used to determine differentially expressed genes (DEGs) by statistical analysis. Lethal concentrations (LC50) for trivalent arsenicals in all cells ranged from 1.6 to 10 μM. MMAIII and DMAIII had 4–12-fold greater potency compared to iAs. Increasing concentrations of iAsIII induced more genes and additional signaling pathways in HBE cells. At equivalent cytotoxic concentrations, greater numbers of DEGs were induced in 1T1 cells compared to the other cells. Each arsenical altered slightly different signaling pathways within and between cell types, but when altered pathways from all three arsenicals were combined, they were similar between cell types. The major signaling pathways altered included NRF2-mediated stress response, interferon, p53, cell cycle regulation and lipid peroxidation. These results show a similar process qualitatively and quantitatively for all three cell types, and support a mode of action involving

  6. Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

    International Nuclear Information System (INIS)

    Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

  7. Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Li-Wu [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Wu, Qiangen [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Green, Bridgett; Nolen, Greg [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Shi, Leming [Division of Systems Biology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); LoSurdo, Jessica [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Deng, Helen [Arkansas Department of Health, Little Rock, AR 72205 (United States); Bauer, Steven [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Fang, Jia-Long, E-mail: jia-long.fang@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Ning, Baitang, E-mail: baitang.ning@fda.hhs.gov [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States)

    2012-07-15

    Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

  8. Natural mineral particles are cytotoxic to rainbow trout gill epithelial cells in vitro.

    Directory of Open Access Journals (Sweden)

    Christian Michel

    Full Text Available Worldwide increases in fluvial fine sediment are a threat to aquatic animal health. Fluvial fine sediment is always a mixture of particles whose mineralogical composition differs depending on the sediment source and catchment area geology. Nonetheless, whether particle impact in aquatic organisms differs between mineral species remains to be investigated. This study applied an in vitro approach to evaluate cytotoxicity and uptake of four common fluvial mineral particles (quartz, feldspar, mica, and kaolin; concentrations: 10, 50, 250 mg L(-1 in the rainbow trout epithelial gill cell line RTgill-W1. Cells were exposed for 24, 48, 72, and 96 h. Cytotoxicity assays for cell membrane integrity (propidium iodide assay, oxidative stress (H2DCF-DA assay, and metabolic activity (MTT assay were applied. These assays were complemented with cell counts and transmission electron microscopy. Regardless of mineral species, particles ≤ 2 µm in diameter were taken up by the cells, suggesting that particles of all mineral species came into contact and interacted with the cells. Not all particles, however, caused strong cytotoxicity: Among all assays the tectosilicates quartz and feldspar caused sporadic maximum changes of 0.8-1.2-fold compared to controls. In contrast, cytotoxicity of the clay particles was distinctly stronger and even differed between the two particle types: mica induced concentration-dependent increases in free radicals, with consistent 1.6-1.8-fold-changes at the 250 mg L(-1 concentration, and a dilated endoplasmic reticulum. Kaolin caused concentration-dependent increases in cell membrane damage, with consistent 1.3-1.6-fold increases at the 250 mg L(-1 concentration. All effects occurred in the presence or absence of 10% fetal bovine serum. Cell numbers per se were marginally affected. Results indicate that (i. natural mineral particles can be cytotoxic to gill epithelial cells, (ii. their cytotoxic potential differs between mineral

  9. Luciferase mRNA Transfection of Antigen Presenting Cells Permits Sensitive Nonradioactive Measurement of Cellular and Humoral Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Tana A. Omokoko

    2016-01-01

    Full Text Available Immunotherapy is rapidly evolving as an effective treatment option for many cancers. With the emerging fields of cancer vaccines and adoptive cell transfer therapies, there is an increasing demand for high-throughput in vitro cytotoxicity assays that efficiently analyze immune effector functions. The gold standard 51Cr-release assay is very accurate but has the major disadvantage of being radioactive. We reveal the development of a versatile and nonradioactive firefly luciferase in vitro transcribed (IVT RNA-based assay. Demonstrating high efficiency, consistency, and excellent target cell viability, our optimized luciferase IVT RNA is used to transfect dividing and nondividing primary antigen presenting cells. Together with the long-lasting expression and minimal background, the direct measurement of intracellular luciferase activity of living cells allows for the monitoring of killing kinetics and displays paramount sensitivity. The ability to cotransfect the IVT RNA of the luciferase reporter and the antigen of interest into the antigen presenting cells and its simple read-out procedure render the assay high-throughput in nature. Results generated were comparable to the 51Cr release and further confirmed the assay’s ability to measure antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. The assay’s combined simplicity, practicality, and efficiency tailor it for the analysis of antigen-specific cellular and humoral effector functions during the development of novel immunotherapies.

  10. Generation of cytotoxic T cell against HBcAg using retrovirally transduced dendritic cells

    Institute of Scientific and Technical Information of China (English)

    Chuan-Lin Ding; Kun Yao; Tian-Tai Zhang; Feng Zhou; Lin Xu; Jiang-Ying Xu

    2003-01-01

    AIM: Cytotoxic T lymphocytes (CTLs) play an important role in resolving HBV infection. In the present study, we attempted to evaluate the efficiency of bone marrow-derived dendritic cells (DCs) transduced with recombinant retroviral vector bearing hepatitis B virus (HBV) core gene and the capability of generating CTLs against HBcAg by genetically modified DCs in vivo.METHODS: A retroviral vector containing HBV core gene was constructed. Replicating DC progenitor of C57BL/6 mice was transduced by retroviral vector and continually cultured in the presence of recombinant mouse granulocytemacrophage colony-stimulating factor (rmGM-CSF) and interleukin-4(IL-4) for 6 days. LPS was added and cultured for additional two days. The efficiency of gene transfer was determined by PCR, Western blot and FACS. Transduced DCs immunized C57BL/6 mice subcutaneously 2 times at an oneweek interval. Intracellular IFN-γ and IL-4 of immunized mice lymphocytes were analyzed. Generation of CTLs in lymphooytes stimulated with mitomycin C-treated EL4-C cell which stably expresses HBcAg was determined by LDH release assays.RESULTS: Recombinant retroviral expression vector (pLCSN) was positively detected by PCR as well as enzyme digestion with EcoRI and BamH I. Retroviruses were generated by pLCSN transfection packing cell and the virus titer was 3x10s CFU/ml. Indirect immunofluorescence and FACS showed that HBV core gene was expressed in murine fibroblasts. Transduced bone marrow cells had capability of differentiating into DCsc in vitro in the presence of rmGMCSF and rmIL-4. The result of PCR showed that HBV core gene was integrated into the genome of transduced DCs.Western blot analysis showed that HBV core gene was expressed in DCs. The transduction rate was 28 % determined by FACS. Retroviral transduction had no influence on DCs expressions of CD80 and MHC class Ⅱ. HBcAg specific CTLs and Th1 type immune responses could be generated in the mice by using transduced DCs as antigen

  11. Differential cytotoxic effects of gold nanoparticles in different mammalian cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Chueh, Pin Ju [Institute of Biomedical Sciences, National Chung Hsing University, Taichung 40227, Taiwan (China); Graduate Institute of Basic Medicine, China Medical University, Taichung 40402, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung 40402, Taiwan (China); Department of Biotechnology, Asia University, Taichung 41354, Taiwan (China); Liang, Ruei-Yue; Lee, Yi-Hui; Zeng, Zih-Ming [Institute of Biomedical Sciences, National Chung Hsing University, Taichung 40227, Taiwan (China); Chuang, Show-Mei, E-mail: smchuang@dragon.nchu.edu.tw [Institute of Biomedical Sciences, National Chung Hsing University, Taichung 40227, Taiwan (China)

    2014-01-15

    Highlights: • AuNPs induce apoptosis in Vero cells. • AuNPs-induced attenuation of cell growth in NIH3T3 cells through autophagy. • Cell-cycle delay was associated with the resistance to AuNPs in MRC-5 cells. • Cell growth was continuously monitored using the measurement of cell impedance. -- Abstract: Gold nanoparticles (AuNPs) possess unique properties that have been exploited in several medical applications. However, a more comprehensive understanding of the environmental safety of AuNPs is imperative for use of these nanomaterials. Here, we describe the impacts of AuNPs in various mammalian cell models using an automatic and dye-free method for continuous monitoring of cell growth based on the measurement of cell impedance. Several well-established cytotoxicity assays were also used for comparison. AuNPs induced a concentration-dependent decrease in cell growth. This inhibitory effect was associated with apoptosis induction in Vero cells but not in MRC-5 or NIH3T3 cells. Interestingly, cDNA microarray analyses in MRC-5 cells supported the involvement of DNA damage and repair responses, cell-cycle regulation, and oxidative stress in AuNP-induced cytotoxicity and genotoxicity. Moreover, autophagy appeared to play a role in AuNPs-induced attenuation of cell growth in NIH3T3 cells. In this study, we present a comprehensive overview of AuNP-induced cytotoxicity in a variety of mammalian cell lines, comparing several cytotoxicity assays. Collectively, these assays offer convincing evidence of the cytotoxicity of AuNPs and support the value of a systematic approach for analyzing the toxicology of nanoparticles.

  12. Differential cytotoxic effects of gold nanoparticles in different mammalian cell lines

    International Nuclear Information System (INIS)

    Highlights: • AuNPs induce apoptosis in Vero cells. • AuNPs-induced attenuation of cell growth in NIH3T3 cells through autophagy. • Cell-cycle delay was associated with the resistance to AuNPs in MRC-5 cells. • Cell growth was continuously monitored using the measurement of cell impedance. -- Abstract: Gold nanoparticles (AuNPs) possess unique properties that have been exploited in several medical applications. However, a more comprehensive understanding of the environmental safety of AuNPs is imperative for use of these nanomaterials. Here, we describe the impacts of AuNPs in various mammalian cell models using an automatic and dye-free method for continuous monitoring of cell growth based on the measurement of cell impedance. Several well-established cytotoxicity assays were also used for comparison. AuNPs induced a concentration-dependent decrease in cell growth. This inhibitory effect was associated with apoptosis induction in Vero cells but not in MRC-5 or NIH3T3 cells. Interestingly, cDNA microarray analyses in MRC-5 cells supported the involvement of DNA damage and repair responses, cell-cycle regulation, and oxidative stress in AuNP-induced cytotoxicity and genotoxicity. Moreover, autophagy appeared to play a role in AuNPs-induced attenuation of cell growth in NIH3T3 cells. In this study, we present a comprehensive overview of AuNP-induced cytotoxicity in a variety of mammalian cell lines, comparing several cytotoxicity assays. Collectively, these assays offer convincing evidence of the cytotoxicity of AuNPs and support the value of a systematic approach for analyzing the toxicology of nanoparticles

  13. Cytotoxic effect of Cousinia verbascifolia Bunge against OVCAR-3 and HT-29 cancer cells

    Directory of Open Access Journals (Sweden)

    Sajjadi Seyed Ebrahim

    2015-01-01

    Full Text Available Introduction: Little information is available about phytochemical and biological properties of Cousinia genus. In a primary study, seven Cousinia species including C. verbascifolia showed cytotoxic activity ranged between 18.4 ± 0.59 to 87.9 ± 0.58 μg/mL. To the best of our knowledge, no other biological studies have been conducted on this plant. Therefore, in this study the cytotoxic effect of Cousinia verbascifolia Bunge against OVCAR-3 and HT-29 cancer cells was evaluated. Methods: Filtration and in vacuo concentration of methanol extract resulted in a green gum which was subjected on reverse column chromatography. Semi polar fraction (41.3 g eluted with water: methanol (20:80, was then subjected on a silica gel column chromatography using hexane/acetone and resulted in 11 fractions. Finally, cytotoxic activities against ovarian and colon cancer cells were determined at a wavelength of 570 nm by Matrix metalloproteinase protein (MTT standard method. Results: None of the fractions showed highly cytotoxic activity. Based on NCI, fractions Fr. 1, Fr. 2, Fr. 4, Fr. 5, Fr. 6, Fr. 8 and Fr. 10 showed moderately cytotoxicity with IC50 values ranged between 119 to 190 μg/mL against OVCAR-3 cells. Fractions Fr. 1, Fr. 2, Fr. 6, Fr. 7 and Fr. 8 showed moderately cytotoxic activity ranged between 118 to 194 μg/mL against HT-29 cells. Fr. 10 and Fr. 11 showed no cytotoxic activity. Conclusion: Due to the inhibitory properties of extract and its fractions on cancer cells, identification of responsible compounds possessing cytotoxic effects for generating possible new approach in medicinal chemistry are recommended.

  14. The cytotoxic effects a of ACA1 on human melanoma cell line

    Directory of Open Access Journals (Sweden)

    R. Yaraie

    2006-01-01

    Full Text Available Background and purpose: Different methods such as surgery, chemotherapy, radiotherapy, hormone therapy and immunotherapy are used for treatment of melanoma cancer. Unfortunately they don't always have desirable results and they may have unfavorable side effects. Researchers try to find new, more effective drugs with low side effects. In this study we evaluated the cytotoxic effect of ACA-1, a water extract of a traditional Iranian medicinal herbs on a melanoma cell line SKMEL-3.Materials and Methods: The SKMEL3 cell line was obtained from Pasture institute, Tehran, Iran and cultured in RPMI media supplemented with 10% FBS. Equal number of cells were added to a 96 well microplate and were incubated with various doses of ACA1 (5,2,1,0.2,0.1,0.05,0.02 and 0.01 mg/ml for 24, 48 and 72 hours in parallel. The cytotoxic effects of the drug was evaluated using MTT assay.Results: The Results showed that ACA1 has significant cytotoxic effects with dose and time dependent manner on SKMEL3. The optimum dose (5 mg/ml showed 47% cytotoxicity in 24 h, 65% cytotoxicity in 48 h and 71% cytotoxicity in 72 h. Conclusion: Based on the results of this research, ACA1 is a suitable candidate for chemotherapy of melanoma patients. Further studies are necessary in order to find effective drugs, their effects on other cell lines and approved in vivo models and clinical trials.

  15. Cytotoxicity of Selected Medicinal and Nonmedicinal Plant Extracts to Microbial and Cervical Cancer Cells

    Directory of Open Access Journals (Sweden)

    Gary M. Booth

    2012-01-01

    Full Text Available This study investigated the cytotoxicity of 55 species of plants. Each plant was rated as medicinal, or nonmedicinal based on the existing literature. About 79% of the medicinal plants showed some cytotoxicity, while 75% of the nonmedicinal plants showed bioactivity. It appears that Asteraceae, Labiatae, Pinaceae, and Chenopodiaceae were particularly active against human cervical cancer cells. Based on the literature, only three of the 55 plants have been significantly investigated for cytotoxicity. It is clear that there is much toxicological work yet to be done with both medicinal and nonmedicinal plants.

  16. HLA-G inhibits xenogenetic cytotoxicity mediated by human NK cells and T lymphocytes against PECs

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In order to investigate whether the non-classi-cal HLA-G classⅠmolecule protects the porcine endothelial cells (PECs) from the lysis mediated by human immune cells in pig to human discordant xenotransplantation, we have cloned HLA-G cDNA from a human placenta by RT-PCR. Mammalian expression vector, pEFG-neo, was constructed by insertion of HLA-G cDNA in pEF-neo. We obtained efficiently expressed PECs by stable transfection. Cytotoxicity assay showed that overexpression of HLA-G on PECs was sufficient to inhibit human NK-92 cell lysis. The level of lysis was equal to or less than that of the lysis of human umbilical vein endothelial cells mediated by human NK-92 cells. It also indicated that HLA-G inhibited the lysis of PECs mediated by xeno-antigen specific T lymphocytes. The reduction of lysis ranged between 59.1% and 88.9%. These findings suggest that the transgenic approach to overexpress HLA-G is believed to be a new immunotherapy in overcoming the immune rejections in xenotransplantion, including delayed xenograft rejection and cell-mediated rejection.

  17. Stability of artemisinin in aqueous environments : Impact on its cytotoxic action to Ehrlich ascites tumour cells

    NARCIS (Netherlands)

    Beekman, AC; Woerdenbag, HJ; Van Uden, W; Pras, N; Konings, AWT; Wikstrom, HV

    1997-01-01

    We have recently shown artemisinin to be cytotoxic against Ehrlich ascites tumour cells. The aim of this study was to investigate the stability of this compound in the aqueous environment of the in-vitro Ehrlich ascites tumour cell system (RPMI 1640 cell culture medium supplemented with 10% foetal b

  18. Cytotoxic Activity and G1 Cell Cycle Arrest of a Dienynone from Echinacea pallida

    DEFF Research Database (Denmark)

    Chicca, Andrea; Adinolfi, Barbara; Pellati, Federica; Orlandini, Giulia; Benvenuti, Stefania; Nieri, Paola

    2009-01-01

    (Jurkat and HL-60), breast carcinoma (MCF-7), and melanoma (MeWo) cells. As part of its mechanism of action, the ability of this constituent to arrest the cell cycle in the G1 phase was demonstrated on HL-60 cells. Furthermore, a stability test of the target compound over 72 h was carried out, indicating......In the present study, a further investigation of the cytotoxic activity of an acetylenic constituent of ECHINACEA PALLIDA roots, namely, pentadeca-(8 Z,13 Z)-dien-11-yn-2-one, was performed, revealing a concentration-dependent cytotoxicity on several human cancer cell lines, including leukemia...

  19. Human herpesvirus-6 enhances natural killer cell cytotoxicity via IL-15.

    OpenAIRE

    Flamand, L.; Stefanescu, I.(Argonne National Laboratory, Argonne, IL, 60439, USA); Menezes, J.

    1996-01-01

    The marked tropism of human herpesvirus-6 (HHV-6) for natural killer (NK) cells and T lymphocytes has led us to investigate the effect of HHV-6 on cellular cytotoxicity. We describe here how HHV-6 infection of peripheral blood mononuclear cells (PBMC) leads to upregulation of their NK cell cytotoxicity. The induction of NK cell activity by HHV-6 was abrogated by monoclonal antibodies (mAbs) to IL-15 but not by mAbs to other cytokines (IFN-alpha, IFN-gamma, TNF-alpha, TNF-beta, IL-2, IL-12) su...

  20. Evaluation of Cytotoxicity and Cell Death Induced In Vitro by Saxitoxin in Mammalian Cells.

    Science.gov (United States)

    Melegari, Silvia P; de Carvalho Pinto, Cátia R S; Moukha, Serge; Creppy, Edmond E; Matias, William G

    2015-01-01

    Since the cyanotoxin saxitoxin (STX) is a neurotoxin and induces ecological changes in aquatic environments, a potential risk to public and environmental health exists. However, data on STX-mediated cytotoxic and genotoxic effects are still scare. In order to gain a better understanding of the effects of this toxin, the cytotoxic and genotoxic potential of STX was examined in two mammalian cell lines. Neuro 2A (N2A), a neuroblastoma mouse cell line, and Vero cell line, derived from Vero green monkey kidney cells, were exposed to several concentrations of STX ranging from 0.5 to 64 nM to determine cell viability, induction of apoptosis (DNA fragmentation assay), and formation of micronuclei (MN) (cytokinesis-block micronucleus assay; CBMN) following 24 h of incubation. The half maximal effective concentration (EC50) values for STX calculated in cell viability tests were 1.01 nM for N2A and 0.82 nM for Vero cells. With increasing STX concentration there was evidence of DNA fragmentation indicating apoptosis induction in Vero cells with a 50% increase in DNA fragmentation compared to control at the highest STX concentration tested (3 nM). The results demonstrated no significant changes in the frequency of micronucleated binucleated cells in N2A and Vero cells exposed to STX, indicating the absence of genotoxicity under these test conditions. There was no apparent cellular necrosis as evidenced by a lack of formation of multinucleated cells. In conclusion, data reported herein demonstrate that STX produced death of both cell types tested through an apoptotic process. PMID:26436995

  1. Cytotoxic activity of water extracts of Trichilia hirta leaves on human tumor cells

    International Nuclear Information System (INIS)

    Trichilia hirta L. (Meliaceae) is traditionally used by patients suffering from cancer as an antitumoral resource. Therefore, the objectives of this study were to evaluate the cytotoxic activity of water extracts of Trichilia hirta leaves on tumour cells and identify through a phytochemical screening the principal families of phytocomponents contained in these extracts. The cytotoxic activity of these extracts was also evaluated on human melanoma cells (SK-mel-3) and human breast carcinoma (T-47D). The African green monkey kidney (AGMK) cells Cercopithecus aethiops (Vero) were used as a non-tumour cells control. The results showed the presence of triterpenes/steroids, saponins, coumarins, reductor sugars, phenols and tannins, flavonoids and carbohydrates/glycosides in the extracts. The water leaf extracts showed cytotoxic activity mainly on tumour cells, which contributes to explain the referred recovery by patients suffering form cancer that traditionally consume these extracts

  2. Cellular uptake and cytotoxicity of positively charged chitosan gold nanoparticles in human lung adenocarcinoma cells

    International Nuclear Information System (INIS)

    Cellular uptake, cytotoxicity, and mechanisms of cytotoxicity of the positively charged Au nanoparticles (NPs) were examined in A549 cells, which are one of the most characterized pulmonary cellular systems. Positively charged Au NPs were prepared by chemical reduction using chitosan. The dimension and surface charge of Au NPs were examined by transmission electron microscopy (TEM), dynamic light scattering, and zeta potential measurements. The uptake of Au NPs into A549 cells was also monitored using TEM and dark-field microscopy (DFM) and z-stack confocal microRaman spectroscopy. DFM live cell imaging was also performed to monitor the entry of chitosan Au NPs in real time. The cytotoxic assay, using both methylthiazol tetrazolium and lactate dehydrogenase assays revealed that positively charged Au NPs decreased cell viability. Flow cytometry, DNA fragmentation, real-time PCR, and western blot analysis suggest that positively charged chitosan Au NPs provoke cell damage through both apoptotic and necrotic pathways.

  3. Cytotoxicity of Buah Merah (Pandanus conoideus Lamk.) Extract on Breast Cancer Cell Line (T47D)

    OpenAIRE

    Tri R Nuringtyas; Yoga Pratama; Galih G; Subagus Wahyuono; Sukarti Moeljopawiro

    2015-01-01

    Buah Merah (Pandanus conoideus Lamk.) has been extensively used to treat various diseases includingcancer. There are many varieties of buah merah and there was no scientifi c study comparing cytotoxicity ofdifferent varieties. The objective of this study was to investigate the cytotoxicity of three varieties of buah merahknown as Barugum, Maler and Yanggiru on breast cancer cell line (T47D). All samples were collected fromPapua, Indonesia. Each sample was extracted consecutively using three s...

  4. Cytotoxicity of Selected Medicinal and Nonmedicinal Plant Extracts to Microbial and Cervical Cancer Cells

    OpenAIRE

    Gary M. Booth; Malmstrom, Robert D.; Erica Kipp; Alexandra Paul

    2012-01-01

    This study investigated the cytotoxicity of 55 species of plants. Each plant was rated as medicinal, or nonmedicinal based on the existing literature. About 79% of the medicinal plants showed some cytotoxicity, while 75% of the nonmedicinal plants showed bioactivity. It appears that Asteraceae, Labiatae, Pinaceae, and Chenopodiaceae were particularly active against human cervical cancer cells. Based on the literature, only three of the 55 plants have been significantly investigated for cytoto...

  5. The selective cytotoxicity elicited by phytochemical extract from Senecio graveolens (Asteraceae) on breast cancer cells is enhanced by hypoxia.

    Science.gov (United States)

    Echiburú-Chau, Carlos; Alfaro-Lira, Susana; Brown, Nelson; Salas, Cristian O; Cuellar, Mauricio; Santander, Javier; Ogalde, Juan Pablo; Rothhammer, Francisco

    2014-04-01

    Breast cancer is the second cause of cancer‑related deaths in woman and the incidence of the disease has increased worldwide, in part due to improvements in early detection. Several drugs with anticancer effects have been extracted from plants in the last 20 years, many of which are particularly effective against breast cancer cells. In particular, we have become interested in the ethanolic extract from Senecio graveolens (synonym of S. nutans), a plant commonly called Chachacoma, in an effort to isolate compounds that could demonstrate cytotoxic effects on breast cancer cells. Senecio (Asteraceae) is the largest gender in Chile comprising approximatly 200 species. These herbs inhabit areas over 3,500 meters above the sea level in the Andes Mountains. S. graveolens is commonly used by local communities for its medicinal properties, particularly its capacity to ameliorate high-altitude-associated sickness. The cytotoxic effect of the alcoholic extract from S. graveolens, as well as its most abundant compound 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone, were tested in the breast cancer cell lines ZR-75-1, MCF-7 and MDA-MB‑231, and non-tumorigenic MCF-10F cells. We show that the phytochemical extract was able to induce cytotoxicity in cancer cells but not in MCF-10F. Importantly, this effect was enhanced under hypoxic conditions. However, 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone, the main compound, did not by itself show an effective anticarcinogenic activity in comparison to the whole extract. Interestingly, the cytotoxic effect of the phytochemical extract was dependent on the basal MnSOD protein expression. Thus, cytotoxicity was increased when MnSOD levels were low, but resistance was evident when protein levels were high. Additionally, the crude extract seems to trigger cell death by a variety of processes, including autophagy, apoptosis and necrosis, in MCF-7 cells. In summary, S. graveolens extract possess anticancer activity displaying a specific

  6. Salmonella enterica serovar Typhi live vector vaccines delivered intranasally elicit regional and systemic specific CD8+ major histocompatibility class I-restricted cytotoxic T lymphocytes.

    Science.gov (United States)

    Pasetti, Marcela F; Salerno-Gonçalves, Rosangela; Sztein, Marcelo B

    2002-08-01

    We investigated the ability of live attenuated Salmonella enterica serovar Typhi strains delivered to mice intranasally to induce specific cytotoxic T-lymphocyte (CTL) responses at regional and systemic levels. Mice immunized with two doses (28 days apart) of Salmonella serovar Typhi strain Ty21a, the licensed oral typhoid vaccine, and genetically attenuated mutants CVD 908 (DeltaaroC DeltaaroD), CVD 915 (DeltaguaBA), and CVD 908-htrA (DeltaaroC DeltaaroD DeltahtrA) induced CTL specific for Salmonella serovar Typhi-infected cells in spleens and cervical lymph nodes. CTL were detected in effector T cells that had been expanded in vitro for 7 days in the presence of Salmonella-infected syngeneic splenocytes. A second round of stimulation further enhanced the levels of specific cytotoxicity. CTL activity was observed in sorted alphabeta+ CD8+ T cells, which were remarkably increased after expansion, but not in CD4+ T cells. CTL from both cervical lymph nodes and spleens failed to recognize Salmonella-infected major histocompatibility complex (MHC)-mismatched cells, indicating that the responses were MHC restricted. Studies in which MHC blocking antibodies were used showed that H-2L(d) was the restriction element. This is the first demonstration that Salmonella serovar Typhi vaccines delivered intranasally elicit CD8+ MHC class I-restricted CTL. The results further support the usefulness of the murine intranasal model for evaluating the immunogenicity of typhoid vaccine candidates at the preclinical level. PMID:12117906

  7. Virus-specific HLA-restricted lysis of herpes simplex virus-infected human monocytes and macrophages mediated by cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Freshly-isolated peripheral blood human monocytes and 5 day in vitro cultured macrophages were infected with herpes simplex virus type 1 (HSV-1), labeled with 51Cr, and used as target cells in a 12-14 hour cell-mediated cytotoxicity assay. Mononuclear leukocytes (MNL) from HSV-1 non-immune individuals, whether unstimulated or stimulated with HSV-1 antigen, did not mediate significant lysis of either target cell. HSV-immune MNL, both freshly-isolated and cultured for 5 days without antigen, demonstrated only low levels of natural killer (NK) cell-mediate lysis. MNL from HSV-immune individuals incubated for 5 days in vitro with HSV-1 antigen mediated significant virus-specific lysis of both target cells. Mean virus-specific lysis of autologous monocytes was 8.5(/+-/2.0)% compared to a three-fold greater virus-specific lysis of autologous macrophages. Greater than 70% of this lytic activity was mediated by Leu-11-negative, T3-positive cytotoxic T lymphocytes (CTL). Allogeneic target cells lacking a common HLA determinant were not significantly lysed while T8-positive CTL mediated infrequent lysis of target cells sharing a common HLA-A and/or HLA-B determinant. T4-positive lymphocytes were demonstrated to be the predominant cell mediating lysis of autologous target cells and allogeneic target cells sharing both HLA-A and/or HLA-B plus HLA-DR determinants with the CTL; the T4-positive cell was the sole CTL mediator of lysis of allogeneic target cells having a common HLA-DR determinant

  8. Arecoline induced cell cycle arrest, apoptosis, and cytotoxicity to human endothelial cells.

    Science.gov (United States)

    Tseng, Shuei-Kuen; Chang, Mei-Chi; Su, Cheng-Yao; Chi, Lin-Yang; Chang, Jenny Zwei-Ching; Tseng, Wan-Yu; Yeung, Sin-Yuet; Hsu, Ming-Lun; Jeng, Jiiang-Huei

    2012-08-01

    Betel quid (BQ) chewing is a common oral habit in South Asia and Taiwan. BQ consumption may increase the risk of oral squamous cell carcinoma (OSCC), oral submucous fibrosis (OSF), and periodontitis as well as systemic diseases (atherosclerosis, hypertension, etc.). However, little is known about the toxic effect of BQ components on endothelial cells that play important roles for angiogenesis, carcinogenesis, tissue fibrosis, and cardiovascular diseases. EAhy 926 (EAHY) endothelial cells were exposed to arecoline, a major BQ alkaloid, for various time periods. Cytotoxicity was estimated by 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. The cell cycle distribution of EAHY cells residing in sub-G0/G1, G0/G1, S-, and G2/M phases was analyzed by propidium iodide staining of cellular DNA content and flow cytometry. Some EAHY cells retracted, became round-shaped in appearance, and even detached from the culture plate after exposure to higher concentrations of arecoline (> 0.4 mM). At concentrations of 0.4 and 0.8 mM, arecoline induced significant cytotoxicity to EAHY cells. At similar concentrations, arecoline induced G2/M cell cycle arrest and increased sub-G0/G1 population, a hallmark of apoptosis. Interestingly, prolonged exposure to arecoline (0.1 mM) for 12 and 21 days significantly suppressed the proliferation of EAHY cells, whereas EAHY cells showed adaptation and survived when exposed to 0.05 mM arecoline. These results suggest that BQ components may contribute to the pathogenesis of OSF and BQ chewing-related cardiovascular diseases via toxicity to oral or systemic endothelial cells, leading to impairment of vascular function. During BQ chewing, endothelial damage may be induced by areca nut components and associate with the pathogenesis of OSF, periodontitis, and cardiovascular diseases. PMID:21847594

  9. Cytotoxicity of protein corona-graphene oxide nanoribbons on human epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Mbeh, Doris A. [Laboratory for Innovation and Analysis of Bio-Performance, École Polytechnique, C.P. 6079, Succursale Centre-ville, Montréal, Québec H3C 3A7 (Canada); Akhavan, Omid, E-mail: oakhavan@sharif.edu [Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, P.O. Box 14588-89694, Tehran (Iran, Islamic Republic of); Javanbakht, Taraneh [Laboratory for Innovation and Analysis of Bio-Performance, École Polytechnique, C.P. 6079, Succursale Centre-ville, Montréal, Québec H3C 3A7 (Canada); Mahmoudi, Morteza [Department of Nanotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences (Iran, Islamic Republic of); Yahia, L’Hocine [Laboratory for Innovation and Analysis of Bio-Performance, École Polytechnique, C.P. 6079, Succursale Centre-ville, Montréal, Québec H3C 3A7 (Canada)

    2014-11-30

    Highlights: • Graphene oxide nanoribons (GONRs) were synthesized by unzipping of multi-walled carbon nanotubes. • GONRs were functionalized by the albumin originated from the two different protein sources. • Concentration-dependent cytotoxicity of the functionalized GONRs was investigated on human epithelial cells. - Abstract: Graphene oxide nanoribbons (GONRs) were synthesized using an oxidative unzipping of multi-walled carbon nanotubes. The interactions of the GONRs with various concentrations of fetal bovine serum or human plasma serum indicated that the GONRs were functionalized substantially by the albumin originated from the two different protein sources. Then, concentration-dependent cytotoxicity of the protein-functionalized GONRs on human epithelial cells was studied. Although the GONRs with concentrations ≤50 μg/mL did not exhibit significant cytotoxicity on the cells (with the cell viability >85%), the concentration of 100 μg/mL exhibited significant cytotoxicity including prevention of cell proliferation and induction of cell apoptosis. These results can provide more in-depth understanding about cytotoxic effects of graphene nanostructures which can be functionalized by the proteins of media.

  10. Cytotoxicity of protein corona-graphene oxide nanoribbons on human epithelial cells

    International Nuclear Information System (INIS)

    Highlights: • Graphene oxide nanoribons (GONRs) were synthesized by unzipping of multi-walled carbon nanotubes. • GONRs were functionalized by the albumin originated from the two different protein sources. • Concentration-dependent cytotoxicity of the functionalized GONRs was investigated on human epithelial cells. - Abstract: Graphene oxide nanoribbons (GONRs) were synthesized using an oxidative unzipping of multi-walled carbon nanotubes. The interactions of the GONRs with various concentrations of fetal bovine serum or human plasma serum indicated that the GONRs were functionalized substantially by the albumin originated from the two different protein sources. Then, concentration-dependent cytotoxicity of the protein-functionalized GONRs on human epithelial cells was studied. Although the GONRs with concentrations ≤50 μg/mL did not exhibit significant cytotoxicity on the cells (with the cell viability >85%), the concentration of 100 μg/mL exhibited significant cytotoxicity including prevention of cell proliferation and induction of cell apoptosis. These results can provide more in-depth understanding about cytotoxic effects of graphene nanostructures which can be functionalized by the proteins of media

  11. Uremic Toxins Enhance Statin-Induced Cytotoxicity in Differentiated Human Rhabdomyosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Hitoshi Uchiyama

    2014-09-01

    Full Text Available The risk of myopathy and rhabdomyolysis is considerably increased in statin users with end-stage renal failure (ESRF. Uremic toxins, which accumulate in patients with ESRF, exert cytotoxic effects that are mediated by various mechanisms. Therefore, accumulation of uremic toxins might increase statin-induced cytotoxicity. The purpose of this study was to determine the effect of four uremic toxins—hippuric acid, 3-carboxy-4-methyl-5-propyl-2-furanpropionate, indole-3-acetic acid, and 3-indoxyl sulfate—on statin-induced myopathy. Differentiated rhabdomyosarcoma cells were pre-treated with the uremic toxins for seven days, and then the cells were treated with pravastatin or simvastatin. Cell viability and apoptosis were assessed by viability assays and flow cytometry. Pre-treatment with uremic toxins increased statin- but not cisplatin-induced cytotoxicity (p < 0.05 vs. untreated. In addition, the pre-treatment increased statin-induced apoptosis, which is one of the cytotoxic factors (p < 0.05 vs. untreated. However, mevalonate, farnesol, and geranylgeraniol reversed the effects of uremic toxins and lowered statin-induced cytotoxicity (p < 0.05 vs. untreated. These results demonstrate that uremic toxins enhance statin-induced apoptosis and cytotoxicity. The mechanism underlying this effect might be associated with small G-protein geranylgeranylation. In conclusion, the increased severity of statin-induced rhabdomyolysis in patients with ESRF is likely due to the accumulation of uremic toxins.

  12. Natural Killer Cell Mediated Cytotoxic Responses in the Tasmanian Devil

    OpenAIRE

    Brown, Gabriella K.; Kreiss, Alexandre; Lyons, A. Bruce; Woods, Gregory M.

    2011-01-01

    The Tasmanian devil (Sarcophilus harrisii), the world's largest marsupial carnivore, is under threat of extinction following the emergence of an infectious cancer. Devil facial tumour disease (DFTD) is spread between Tasmanian devils during biting. The disease is consistently fatal and devils succumb without developing a protective immune response. The aim of this study was to determine if Tasmanian devils were capable of forming cytotoxic antitumour responses and develop antibodies against D...

  13. The cytotoxicity and genotoxicity of soluble and particulate cobalt in human lung fibroblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Leah J.; Holmes, Amie L. [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Kandpal, Sanjeev Kumar; Mason, Michael D. [Department of Chemical and Biological Engineering, University of Maine, Orono, ME (United States); Zheng, Tongzhang [Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT (United States); Wise, John Pierce, E-mail: John.Wise@usm.maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States)

    2014-08-01

    Cobalt exposure is increasing as cobalt demand rises worldwide due to its use in enhancing rechargeable battery efficiency, super-alloys, and magnetic products. Cobalt is considered a possible human carcinogen with the lung being a primary target. However, few studies have considered cobalt-induced toxicity in human lung cells. Therefore, in this study, we sought to determine the cytotoxicity and genotoxicity of particulate and soluble cobalt in human lung cells. Cobalt oxide and cobalt chloride were used as representative particulate and soluble cobalt compounds, respectively. Exposure to both particulate and soluble cobalt induced a concentration-dependent increase in cytotoxicity, genotoxicity, and intracellular cobalt ion levels. Based on intracellular cobalt ion levels, we found that soluble cobalt was more cytotoxic than particulate cobalt while particulate and soluble cobalt induced similar levels of genotoxicity. However, soluble cobalt induced cell cycle arrest indicated by the lack of metaphases at much lower intracellular cobalt concentrations compared to cobalt oxide. Accordingly, we investigated the role of particle internalization in cobalt oxide-induced toxicity and found that particle-cell contact was necessary to induce cytotoxicity and genotoxicity after cobalt exposure. These data indicate that cobalt compounds are cytotoxic and genotoxic to human lung fibroblasts, and solubility plays a key role in cobalt-induced lung toxicity. - Highlights: • Particulate and soluble cobalt are cytotoxic and genotoxic to human lung cells. • Soluble cobalt induces more cytotoxicity compared to particulate cobalt. • Soluble and particulate cobalt induce similar levels of genotoxicity. • Particle-cell contact is required for particulate cobalt-induced toxicity.

  14. The cytotoxicity of nitroaromatic hypoxic cell radiosensitizers on mammalian cells in vitro

    International Nuclear Information System (INIS)

    The cytotoxic action of several representative nitroaromatic compounds towards Chinese hamster V79 cells in vitro was investigated. Particular reference is made to the 2-nitroimidazole, misonidazole. The results showed that compounds, which are likely to affect the rate and extent of reduction of the nitro group, can alter the cytotoxicity of nitroaromatic compounds under hypoxic conditions. Inhibition of oxygen utilization in aerobic cells by respiratory inhibitors can be relieved by the addition of misonidazole. The presence of these inhibitors or exogenous compounds which can act as energy sources, can change the survival response of mammalian cells to misonidazole both aerobic and hypoxic conditions. Post-incubation of cells in caffeine after exposure to either misonidazole, metronidazole or nitrofurantoin accentuates the degree of cell-killing, probably by inhibition of repair of DNA damage. Several of these nitroaromatic compounds are weakly mutagenic, as demonstrated by resistance to the toxic action of Ouabain and Thioguanine. The mechanistic implications of these results and the relevance to the use of these compounds in cancer therapy are discussed. (author)

  15. In vitro evaluation of cytotoxicity of engineered carbon nanotubes in selected human cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xiaoke; Cook, Sean; Wang, Peng [Department of Biology, Jackson State University, P.O. Box 18540, Jackson, MS 39217 (United States); Hwang, Huey-min, E-mail: huey-min.hwang@jsums.edu [Department of Biology, Jackson State University, P.O. Box 18540, Jackson, MS 39217 (United States); Liu, Xi; Williams, Quinton L. [Department of Physics, Atmospheric Sciences and Geoscience, Jackson State University, P.O. Box 17660, Jackson, MS 39217 (United States)

    2010-03-15

    In this study, we used a systematic approach to study and compare the in vitro cytotoxicity of selected engineered carbon nanotubes (CNTs) to test cell lines including human skin keratinocytes, lung cells and lymphocytes. Results of fluorescein diacetate (FDA) uptake in T4 lymphocyte A3 cells indicated cytotoxicity caused by single-walled carbon nanotubes (SWCNTs) at concentrations of 2, 5 and 10 ppm. At 2 ppm, the SWCNT treatment group retained 71.3% viability compared to the PBS control group. At 10 ppm, cellular viability further decreased to 56.5% of the PBS control group. In the skin keratinocyte HaCaT cells and lung MSTO-211H cells, the SWCNT did not demonstrate any cytotoxicity at concentrations of 2 and 5 ppm but slightly inhibited HaCaT cells and caused significant toxicity to MSTO-211H cells at 10 ppm. Multi-walled carbon nanotube (MWCNT) testing showed significant cytotoxicity to A3 cells in a dose-dependent manner. At 10 ppm the viability of the cells decreased to 89.1% compared to the PBS control. In MSTO-211H cells, MWCNT caused significant toxicity at concentrations of 2 ppm and higher. By comparison, HaCaT cells were inhibited significantly only at 10 ppm. Overall, the test CNTs inhibited cellular viabilities in a concentration, cell type, and CNT type-dependent pattern. The viabilities of the MWCNT-impacted cells are higher than the corresponding SWCNT groups. We speculate that on a per volume basis, the greater availability of defects and contaminants for cellular interaction may contribute to the higher cytotoxicity of SWCNT in this study. The interaction between the SWCNTs and A3 lymphocytes was also observed by scanning electron microscopy. The mechanism for causing cell death in this study was attributed to apoptosis and necrosis after physical penetration by CNTs and oxidative stress via formation of reactive oxygen species.

  16. In vitro evaluation of cytotoxicity of engineered carbon nanotubes in selected human cell lines

    International Nuclear Information System (INIS)

    In this study, we used a systematic approach to study and compare the in vitro cytotoxicity of selected engineered carbon nanotubes (CNTs) to test cell lines including human skin keratinocytes, lung cells and lymphocytes. Results of fluorescein diacetate (FDA) uptake in T4 lymphocyte A3 cells indicated cytotoxicity caused by single-walled carbon nanotubes (SWCNTs) at concentrations of 2, 5 and 10 ppm. At 2 ppm, the SWCNT treatment group retained 71.3% viability compared to the PBS control group. At 10 ppm, cellular viability further decreased to 56.5% of the PBS control group. In the skin keratinocyte HaCaT cells and lung MSTO-211H cells, the SWCNT did not demonstrate any cytotoxicity at concentrations of 2 and 5 ppm but slightly inhibited HaCaT cells and caused significant toxicity to MSTO-211H cells at 10 ppm. Multi-walled carbon nanotube (MWCNT) testing showed significant cytotoxicity to A3 cells in a dose-dependent manner. At 10 ppm the viability of the cells decreased to 89.1% compared to the PBS control. In MSTO-211H cells, MWCNT caused significant toxicity at concentrations of 2 ppm and higher. By comparison, HaCaT cells were inhibited significantly only at 10 ppm. Overall, the test CNTs inhibited cellular viabilities in a concentration, cell type, and CNT type-dependent pattern. The viabilities of the MWCNT-impacted cells are higher than the corresponding SWCNT groups. We speculate that on a per volume basis, the greater availability of defects and contaminants for cellular interaction may contribute to the higher cytotoxicity of SWCNT in this study. The interaction between the SWCNTs and A3 lymphocytes was also observed by scanning electron microscopy. The mechanism for causing cell death in this study was attributed to apoptosis and necrosis after physical penetration by CNTs and oxidative stress via formation of reactive oxygen species.

  17. Preliminary Study on Cytotoxic Effect of Biodegradation of Magnesium on Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Yu Zhang; Ling Ren; Mei Li; Xiao Lin; Huafu Zhao; Ke Yang

    2012-01-01

    Biodegradation of magnesium (Mg) based metals in body fluid can lead to a strong alkalinity as well as an increase of Mg2+ concentration in its surrounding environment. In vitro cytotoxic effects of the extracts of pure Mg with and without micro arc oxidation (MAO) coating on osteosarcoma U2-OS cells, a kind of bone cancer cells, were preliminarily studied, independently considering the increase of either alkalinity or Mg2+ concentration. The results indicated that the high alkalinity, i.e., a great increase of pH value, caused by the degradations of Mg with and without MAO coating in the culture medium all showed strong cytotoxic effects on U2-OS cells. However, the increase of Mg2+ concentration had no such cytotoxic effect. This finding may provide an alternative way to cure bone cancers through creating a high alkalinity surrounding the cancer cells.

  18. Cytotoxicity assessment of antibiofouling compounds and by-products in marine bivalve cell cultures.

    Science.gov (United States)

    Domart-Coulon, I; Auzoux-Bordenave, S; Doumenc, D; Khalanski, M

    2000-06-01

    Short-term primary cell cultures were derived from adult marine bivalve tissues: the heart of oyster Crassostrea gigas and the gill of clam Ruditapes decussatus. These cultures were used as experimental in vitro models to assess the acute cytotoxicity of an organic molluscicide, Mexel-432, used in antibiofouling treatments in industrial cooling water systems. A microplate cell viability assay, based on the enzymatic reduction of tetrazolium dye (MTT) in living bivalve cells, was adapted to test the cytotoxicity of this compound: in both in vitro models, toxicity thresholds of Mexel-432 were compared to those determined in vivo with classic acute toxicity tests. The clam gill cell model was also used to assess the cytotoxicity of by-products of chlorination, a major strategy of biofouling control in the marine environment. The applications and limits of these new in vitro models for monitoring aquatic pollutants were discussed, in reference with the standardized Microtox test. PMID:10806375

  19. Cytotoxic activity of coumarins from the fruits of Cnidium monnieri on leukemia cell lines.

    Science.gov (United States)

    Yang, Ling-Ling; Wang, Min-Chieh; Chen, Lih-Geeng; Wang, Ching-Chiung

    2003-12-01

    Cnidii monnieri Fructus [CmF; Cnidium monnieri (L.) Cusson] is used as a tonic agent in traditional Chinese medicine. In a previous Chinese herb-cytotoxicity screening test, the ethanol extract of CmF exhibited strong effects on human leukemia (HL-60), cervical carcinoma (HeLa) and colorectal carcinoma (CoLo 205) cells. Then, the CmF extract was subjected to silica gel column chromatography and recrystallization to give five coumarins: osthol, imperatorin, bergapten, isopimpinellin, and xanthotoxin. Among these compounds, osthol showed the strongest cytotoxic activity on tumor cell lines. The structure-activity relationship established from the results indicated that the prenyl group has an important role in the cytotoxic effects. However, imperatorin showed the highest sensitivity to HL-60 cells and the least cytotoxicity to normal PBMCs. Osthol and imperatorin both caused apoptotic bodies, DNA fragmentation, and enhanced PARP degradation in HL-60 cells by biochemical analysis. These results indicate that osthol and imperatorin can induce apoptosis in HL-60 cells. Therefore, osthol and imperatorin are cytotoxic marker substances in the fruits of Cnidium monnieri. PMID:14750023

  20. DMSO exhibits similar cytotoxicity effects to thalidomide in mouse breast cancer cells

    OpenAIRE

    Öz, Ece Simsek; Aydemir, Esra; Fışkın, Kayahan

    2012-01-01

    The purpose of this study was to evaluate the cytotoxic effect of thalidomide on 4T1 and 4THMpc mouse breast cancer cell lines. Mouse breast cancer cells (4T1) and cells derived from metastatic lesions (4THMpc) were treated with various doses of thalidomide [10-2-100 µM dissolved in dimethyl sulfoxide (DMSO) as recommended] and 1.4 µM DMSO (maximum DMSO concentration in the highest thalidomide dose) as a DMSO control against the untreated control groups. MTT was used to evaluate the cytotoxic...

  1. Cytotoxic activity of labdane type diterpenes against human leukemic cell lines in vitro.

    Science.gov (United States)

    Dimas, K; Demetzos, C; Marsellos, M; Sotiriadou, R; Malamas, M; Kokkinopoulos, D

    1998-04-01

    Nine labdane type diterpenes isolated from the plant Cistus creticus subsp. creticus and from the resin "Ladano" which is excreted on the surface of the leaves and stems of this plant, were examined for their in vitro cytotoxic activity against 14 human leukemic cell lines. Compound 1, (13E)-labd-13-ene-8 alpha,15-diol, exhibited cytotoxic activity against 13 of the cell lines tested, while compound 2, (13E)-labd-7,13-dienol, was active only against HL60 cells. Further compound 1 was examined for its effect on the uptake of [3H]-thymidine as a marker of DNA synthesis. PMID:9581515

  2. Cytotoxic effects of new MTA-based cement formulations on fibroblast-like MDPL-20 cells

    Directory of Open Access Journals (Sweden)

    Lucas da Fonseca Roberti GARCIA

    2016-01-01

    Full Text Available Abstract The present study aimed at evaluating the cytotoxic effects of a novel cement called CER on periodontal fibroblast-like cells of mice (MDPL-20, in comparison with different formulations of Mineral Trioxide Aggregate (MTA, by means of the cell viability test (MTT and cell morphology analysis. Thirty-two round-shaped samples were fabricated with the following cements: white MTA, white and gray CER and experimental white MTA. The samples were immersed in serum-free culture medium for 24 hours or 7 days (n = 16. The extracts (culture medium + components released from the cements were applied for 24 hours to previously cultured cells (40.000 cells/cm2 in the wells of 24-well plates. Cells seeded in complete culture medium were used as a negative control. Cell viability was assessed using the MTT assay. Two samples of each cement were used for cell morphology analysis by Scanning Electron Microscopy (SEM. The extracts obtained at the 7-day period presented higher cytotoxicity compared with the 24-hour period (p 0.05. However, at the 7-day period, the experimental white MTA presented no significant difference in comparison with the other cements (p > 0.05. At the 7-day period, CER cement presented cytotoxic effects on fibroblast-like cells, similar to different MTA formulations. However, the immersion period in the culture medium influenced the cytotoxicity of the cements, which was greater for CER cement at 24 hours.

  3. In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Paula M Kustiawan; Songchan Puthong; Enos T Arung; Chanpen Chanchao

    2014-01-01

    Objective: To screen crude extracts of propolis, bee pollen and honey from four stingless bee species [Trigona incisa (T. incisa)], Timia apicalis, Trigona fusco-balteata and Trigona fuscibasis) native to East Kalimantan, Indonesia for cytotoxic activity against five human cancer cell lines (HepG2, SW620, ChaGo-I, KATO-III and BT474).Methods:All samples were extracted with methanol, and then subpartitioned with n-hexane and ethyl acetate. Each crude extract was screened at 20 µg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, four previously shown bioactive components from propolis (apigenin, caffeic acid phenyl ester, kaempferol and naringenin) and two chemotherapeutic drugs (doxorubicin and 5-fluorouracil) were used to evaluate the sensitivity of the cell lines.Results:Overall, crude extracts from propolis and honey had higher cytotoxic activities than bee pollen, but the activity was dependent upon the extraction solvent, bee species and cell line. Propolis extracts from T. incisa and Timia apicalis showed the highest and lowest cytotoxic activity, respectively. Only the HepG2 cell line was broadly sensitive to the honey extracts. For pure compounds, doxorubicin was the most cytotoxic, the four propolis compounds the least, but the ChaGo-I cell line was sensitive to kaempferol at 10 µg/mL and KATO-III was sensitive to kaempferol and apigenin at 10 µg/mL. All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from T. incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines. Further study is required, including the isolation and characterization of the active antiproliferative agent(s).

  4. Melanoma cells treated with GGTI and IFN-gamma allow murine vaccination and enhance cytotoxic response against human melanoma cells.

    Directory of Open Access Journals (Sweden)

    Guillaume Sarrabayrouse

    Full Text Available BACKGROUND: Suboptimal activation of T lymphocytes by melanoma cells is often due to the defective expression of class I major histocompatibility antigens (MHC-I and costimulatory molecules. We have previously shown that geranylgeranyl transferase inhibition (done with GGTI-298 stimulates anti-melanoma immune response through MHC-I and costimulatory molecule expression in the B16F10 murine model [1]. METHODOLOGY/PRINCIPAL FINDINGS: In this study, it is shown that vaccination with mIFN-gand GGTI-298 pretreated B16F10 cells induces a protection against untreated tumor growth and pulmonary metastases implantation. Furthermore, using a human melanoma model (LB1319-MEL, we demonstrated that in vitro treatment with hIFN-gamma and GGTI-298 led to the up regulation of MHC-I and a costimulatory molecule CD86 and down regulation of an inhibitory molecule PD-1L. Co-culture experiments with peripheral blood mononuclear cells (PBMC revealed that modifications induced by hIFN-gamma and GGTI-298 on the selected melanoma cells, enables the stimulation of lymphocytes from HLA compatible healthy donors. Indeed, as compared with untreated melanoma cells, pretreatment with hIFN-gamma and GGTI-298 together rendered the melanoma cells more efficient at inducing the: i activation of CD8 T lymphocytes (CD8+/CD69+; ii proliferation of tumor-specific CD8 T cells (MelanA-MART1/TCR+; iii secretion of hIFN-gamma; and iv anti-melanoma specific cytotoxic cells. CONCLUSIONS/SIGNIFICANCE: These data indicate that pharmacological treatment of melanoma cell lines with IFN-gamma and GGTI-298 stimulates their immunogenicity and could be a novel approach to produce tumor cells suitable for vaccination and for stimulation of anti-melanoma effector cells.

  5. Cytotoxic effects of mono-(2-ethylhexyl) phthalate on human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    SHI Cheng; CHEN Xi; CAI Xiao-hui; YU Wei-dong; LIANG Rong; LU Qun; SHEN Huan

    2013-01-01

    Background Mono-(2-ethylhexyl) phthalate (MEHP),the metabolite of di-(2-ethylhexyl) phthalate (DEHP),was suspected to be toxic to human embryos.This study contributes to investigating its toxic effects by an embryonic stem cell test (EST) based on two human embryonic stem cell (hESCs) lines.Methods CH1 established in our own lab and H1,a federally registered cell line were two human embryonic stem cell lines used in this test.Four endpoint measurements were performed consisting of cell viability,proliferation ability,apoptosis as well as changes of gene expression patterns after spontaneous differentiation were determined.For measuring effects on the first three endpoints,the cells were treated with various concentrations of MEHP dissolved in dimethyl sulfoxide (DMSO) and only with DMSO which served as control and harvested after 5 days.For measuring effects during spontaneous differentiation,the RNA of embryoid bodies (EBs) formed after 8 days' MEHP exposure was collected and changes in differentiation specific gene expression patterns were analyzed by quantitative real time RT-PCR.Results As a result the viability and proliferation ability of both cell lines decreased significantly at 1000 μmol/L MEHP,while there was no effect on apoptosis or cell morphology.In addition MEHP also changed the gene expression pattern in the EBs of both cell lines.Conclusion MEHP in a high dose was cytotoxic and affected the development of hESCs,which indicates its embryo toxicity in human embryos.

  6. Cytotoxicity of clove (Syzygium aromaticum) oil and its major components to human skin cells.

    Science.gov (United States)

    Prashar, A; Locke, I C; Evans, C S

    2006-08-01

    The essential oil extracted from clove (Syzygium aromaticum) is used as a topical application to relieve pain and promote healing in herbal medicine and also finds use in the fragrance and flavouring industries. Clove oil has two major components, eugenol and beta-caryophyllene, which constitute 78% and 13% of the oil, respectively. Clove oil and these components are generally recognized as 'safe', but the in-vitro study here demonstrates cytotoxic properties of both the oil and eugenol, towards human fibroblasts and endothelial cells. Clove oil was found to be highly cytotoxic at concentrations as low as 0.03% (v/v) with up to 73% of this effect attributable to eugenol. beta-caryophyllene did not exhibit any cytotoxic activity, indicating that other cytotoxic components may also exist within the parent oil. PMID:16872360

  7. Cytotoxicity and genotoxicity assessment of Euphorbia hirta in MCF-7 cell line model using comet assay

    Institute of Scientific and Technical Information of China (English)

    Kwan Yuet Ping; Ibrahim Darah; Yeng Chen; Sreenivasan Sasidharan

    2013-01-01

    Objective:To evaluate the cytotoxicity and genotoxicity activity of Euphorbia hirta (E. hirta) in MCF-7 cell line model using comet assay. Methods: The cytotoxicity of E. hirta extract was investigated by employing brine shrimp lethality assay and the genotoxicity of E. hirta was assessed by using Comet assay. Results: Both toxicity tests exhibited significant toxicity result. In the comet assay, the E. hirta extract exhibited genotoxicity effects against MCF-7 DNA in a time-dependent manner by increasing mean percentage of DNA damage. The extract of E. hirta showed significant toxicity against brine shrimp with an LC50 value of 620.382 μg/mL (24 h). Comparison with positive control potassium dichromate signifies that cytotoxicity exhibited by the methanol extract might have moderate activity. Conclusion:The present work confirmed the cytotoxicity and genotoxicity of E. hirta. However, the observed toxicity of E. hirta extracts needs to be confirmed in additional studies.

  8. Epitope specificity of human immunodeficiency virus-1 antibody dependent cellular cytotoxicity [ADCC] responses.

    Science.gov (United States)

    Pollara, Justin; Bonsignori, Mattia; Moody, M Anthony; Pazgier, Marzena; Haynes, Barton F; Ferrari, Guido

    2013-07-01

    Antibody dependent cellular cytotoxicity [ADCC] has been suggested to play an important role in control of Human Immunodeficiency Virus-1 [HIV-1] viral load and protection from infection. ADCC antibody responses have been mapped to multiple linear and conformational epitopes within the HIV-1 envelope glycoproteins gp120 and gp41. Many epitopes targeted by antibodies that mediate ADCC overlap with those recognized by antibodies capable of virus neutralization. In addition, recent studies conducted with human monoclonal antibodies derived from HIV-1 infected individuals and HIV-1 vaccine-candidate vaccinees have identified a number of antibodies that lack the ability to capture primary HIV-1 isolates or mediate neutralizing activity, but are able to bind to the surface of infected CD4+ T cells and mediate ADCC. Of note, the conformational changes in the gp120 that may not exclusively relate to binding of the CD4 molecule are important in exposing epitopes recognized by ADCC responses. Here we discuss the HIV-1 envelope epitopes targeted by ADCC antibodies in the context of the potential protective capacities of ADCC. PMID:24191939

  9. Regulatory T cells and IL-10 independently counterregulate cytotoxic T lymphocyte responses induced by transcutaneous immunization.

    Directory of Open Access Journals (Sweden)

    Pamela Stein

    Full Text Available BACKGROUND: The imidazoquinoline derivate imiquimod induces inflammatory responses and protection against transplanted tumors when applied to the skin in combination with a cognate peptide epitope (transcutaneous immunization, TCI. Here we investigated the role of regulatory T cells (T(reg and the suppressive cytokine IL-10 in restricting TCI-induced cytotoxic T lymphocyte (CTL responses. METHODOLOGY/PRINCIPAL FINDINGS: TCI was performed with an ointment containing the TLR7 agonist imiquimod and a CTL epitope was applied to the depilated back skin of C57BL/6 mice. Using specific antibodies and FoxP3-diphteria toxin receptor transgenic (DEREG mice, we interrogated inhibiting factors after TCI: by depleting FoxP3(+ regulatory T cells we found that specific CTL-responses were greatly enhanced. Beyond this, in IL-10 deficient (IL-10(-/- mice or after blocking of IL-10 signalling with an IL-10 receptor specific antibody, the TCI induced CTL response is greatly enhanced indicating an important role for this cytokine in TCI. However, by transfer of T(reg in IL-10(-/- mice and the use of B cell deficient JHT(-/- mice, we can exclude T(reg and B cells as source of IL-10 in the setting of TCI. CONCLUSION/SIGNIFICANCE: We identify T(reg and IL-10 as two important and independently acting suppressors of CTL-responses induced by transcutaneous immunization. Advanced vaccination strategies inhibiting T(reg function and IL-10 release may lead the development of effective vaccination protocols aiming at the induction of T cell responses suitable for the prophylaxis or treatment of persistent infections or tumors.

  10. Generation of MHC class I-restricted cytotoxic T cell lines and clones against colonic epithelial cells from ulcerative colitis.

    Science.gov (United States)

    Yonamine, Y; Watanabe, M; Kinjo, F; Hibi, T

    1999-01-01

    We established CTL lines and clones against colonic epithelial cells from PBLs of patients with ulcerative colitis by continuous stimulation with HLA-A locus-matched colonic epithelial cell lines. We developed a nonradioactive europium release cytotoxicity assay to detect CTLs. PBLs from 3 of 12 patients but not from any of 14 normal controls who shared at least one haplotype of HLA-A locus with two colonic epithelial cell lines, CW2 and ACM, showed increased cytotoxicity against these lines. Three CTL lines established from the PBLs of patients showed increased cytotoxicity against HLA-A locus-matched CW2 or ACM but not against matched lung or esophagus cell lines. The phenotypes of CTL lines were alpha beta-TCR+ CD3+ CD8+ CD16-. The CTL line MS showed increased cytotoxicity against freshly isolated colonic epithelial cells but not against cells with a different HLA-A locus. Two CTL clones were generated from MS and clone 3-2, expressing CD3+ CD8+ CD4- CD56-, showed high MHC class I-restricted cytotoxicity against the colonic epithelial cells. These results indicated that CTLs against colonic epithelial cells may contribute to epithelial cell damage in ulcerative colitis. PMID:10080107

  11. Hypoxia-inducible miR-210 regulates the susceptibility of tumor cells to lysis by cytotoxic T cells.

    Science.gov (United States)

    Noman, Muhammad Zaeem; Buart, Stéphanie; Romero, Pedro; Ketari, Sami; Janji, Bassam; Mari, Bernard; Mami-Chouaib, Fathia; Chouaib, Salem

    2012-09-15

    Hypoxia in the tumor microenvironment plays a central role in the evolution of immune escape mechanisms by tumor cells. In this study, we report the definition of miR-210 as a miRNA regulated by hypoxia in lung cancer and melanoma, documenting its involvement in blunting the susceptibility of tumor cells to lysis by antigen-specific cytotoxic T lymphocytes (CTL). miR-210 was induced in hypoxic zones of human tumor tissues. Its attenuation in hypoxic cells significantly restored susceptibility to autologous CTL-mediated lysis, independent of tumor cell recognition and CTL reactivity. A comprehensive approach using transcriptome analysis, argonaute protein immunoprecipitation, and luciferase reporter assay revealed that the genes PTPN1, HOXA1, and TP53I11 were miR-210 target genes regulated in hypoxic cells. In support of their primary importance in mediating the immunosuppressive effects of miR-210, coordinate silencing of PTPN1, HOXA1, and TP53I11 dramatically decreased tumor cell susceptibility to CTL-mediated lysis. Our findings show how miR-210 induction links hypoxia to immune escape from CTL-mediated lysis, by providing a mechanistic understanding of how this miRNA mediates immunosuppression in oxygen-deprived regions of tumors where cancer stem-like cells and metastatic cellular behaviors are known to evolve. PMID:22962263

  12. CD8+ T lymphocytes of patients with AIDS maintain normal broad cytolytic function despite the loss of human immunodeficiency virus-specific cytotoxicity

    International Nuclear Information System (INIS)

    In this study, the authors have investigated the potential mechanisms responsible for the loss of human immunodeficiency virus type 1 (HIV-1)-specific cytolytic activity in the advanced stages of HIV-1 infection. They have demonstrated that HIV-1-specific cytotoxic T lymphocytes are predominantly contained within the CD8+DR+ subset. Furthermore, they have shown by a redirected killing assay that there is a dichotomy between HIV-1-specific cytolytic activity and broad cytolytic potential since the cytolytic machinery of CD8+DR+ cells is still functioning even in patients with AIDS who have lost their HIV-1-specific cytolytic activity. In addition, by comparative analysis of these two types of cytolytic activity over time they have demonstrated a progressive loss of HIV-1-specific cytolytic activity in the advanced stages of the disease, whereas the cytolytic potential remained unchanged regardless of the clinical stage. On the basis of these results, they propose that the loss of HIV-1-specific cytolytic activity in HIV-1-infected individuals may result at least in part from a progressive decrease in the pool of HIV-1-specific cytotoxic T lymphocytes belonging to the CD8+DR+ subset whose ability to expand has been impaired

  13. Reduced cytotoxicity and enhanced bioactivity of cationic antimicrobial peptides liposomes in cell cultures and 3D epidermis model against HSV.

    Science.gov (United States)

    Ron-Doitch, Sapir; Sawodny, Beate; Kühbacher, Andreas; David, Mirjam M Nordling; Samanta, Ayan; Phopase, Jaywant; Burger-Kentischer, Anke; Griffith, May; Golomb, Gershon; Rupp, Steffen

    2016-05-10

    Cationic antimicrobial peptides (AMPs) are part of the innate immunity, and act against a wide variety of pathogenic microorganisms by perturbation of the microorganism's plasma membrane. Although attractive for clinical applications, these agents suffer from limited stability and activity in vivo, as well as non-specific interaction with host biological membranes, leading to cytotoxic adverse effects. We hypothesized that encapsulation of AMPs within liposomes could result in reduced cytotoxicity, and with enhanced stability as well as bioactivity against herpes simplex virus 1 (HSV-1). We formulated nano-sized liposomal formulations of LL-37 and indolicidin, and their physicochemical properties, cellular uptake, in vitro cytotoxicity and antiviral efficacy have been determined. Lower cytotoxicity of LL-37 liposomes was found in comparison to indolicidin liposomes attributed to the superior physicochemical properties, and to the different degree of interaction with the liposomal membrane. The disc-like shaped LL-37 liposomes (106.8±10.1nm, shelf-life stability of >1year) were taken up more rapidly and to a significantly higher extent than the free peptide by human keratinocyte cell line (HaCaT), remained intact within the cells, followed by release of the active peptide within the cytoplasm and migration of the vesicles' lipids to the plasma membrane. LL-37 liposomes were found significantly less toxic than both the free agent and liposomal indolicidin. In the new 3D epidermis model (immortalized primary keratinocytes) liposomal LL-37 treatment (>20μM), but not free LL-37, efficiently protected the epidermis, inhibiting HSV-1 infection. This positive antiviral effect was obtained with no cytotoxicity even at very high concentrations (400μM). Thus, the antiviral activity of encapsulated LL-37 was significantly improved, expanding its therapeutic window. Liposomal LL-37 appears to be a promising delivery system for HSV therapy. PMID:27012977

  14. Role of quercetin on Caco-2 cells against cytotoxic effects of alternariol and alternariol monomethyl ether.

    Science.gov (United States)

    Fernández-Blanco, Celia; Font, Guillermina; Ruiz, Maria-Jose

    2016-03-01

    Molds of the genus Alternaria have been reported as contaminants of a variety of food and feed. Alternaria toxins such as alternariol (AOH) and its naturally occurring monomethyl ether (AME) produce cytotoxicity and oxidative stress in cell cultures. On the other hand, it has been proved that natural polyphenols have antioxidant effect. Quercetin (Quer) is a polyphenol present in berries and other commodities which exhibits these effects. The aims were to evaluate the cytotoxicity of AOH, AME and the binary combination of them, and the cytoprotective effect of Quer exposed simultaneously with AOH, AME and the mycotoxin mixture in human adenocarcinoma (Caco-2) cells. The cytotoxicity and the cytoprotective effect were determined by the MTT test after 24 and 48 h of exposure and interactions were evaluated with the isobologram analysis method. Cell viability decreased after 48 h of AOH and AME exposures, being the binary combination more cytotoxic, causing a synergism effect. No cytoprotective effect of Quer against AOH and AME was observed when they were exposed simultaneously in Caco-2 cells. The cytoprotective effect of Quer against mycotoxins (AOH, AME or other different which could present higher cytotoxic effect) depends on the concentration, the presence and the interaction between the compounds in food. PMID:26802676

  15. Specific antioxidant compounds differentially modulate cytotoxic activity of doxorubicin and cisplatin: in vitro and in vivo study

    OpenAIRE

    Panchuk, Rostyslav; Skorokhyd, Nadia; Chumak, Vira; Lehka, Lilya; Omelyanchik, Sofya; Gurinovich, Valery; Moiseenok, Andrey; Heffeter, Petra; Berger, Walter; Stoika, Rostyslav

    2014-01-01

    Aim To use the antioxidant compounds (sodium selenite, selenomethionine, D-pantethine) for modulation of cytotoxic effect of doxorubicin and cisplatin toward wild type and drug-resistant mutants of several human tumor cells. Similar treatments were applied in vivo toward adult male Wistar rats. Methods Human tumor cells of different lines (HCT-116, Jurkat and HL-60) with various mechanisms of drug-resistance were treated with doxorubicin or cisplatin, alone or in combination with sodium selen...

  16. Effects of spider Macrothele raven venom on cell proliferation and cytotoxicity in HeLa cells

    Institute of Scientific and Technical Information of China (English)

    Li GAO; Bao-en SHAN; Jing CHEN; Jiang-hui LIU; Da-xiang SONG; Bao-cheng ZHU

    2005-01-01

    Aim: To examine the effect of venom from the spider Macrothele raven on cell proliferation and cytotoxicity in human cervical carcinoma, HeLa cells. Methods:Morphological and biochemical signs of apoptosis appeared using acridine orange-ethidium bromide (AO/EB) staining. Marked morphological changes in HeLa cells after treatment with spider venom were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell proliferation and cytotoxicity were determined by [methyl-3H] thymidine assay ([3H]TdR) and lactate dehydrogenase (LDH) release, respectively. DNA fragmentation and cell cycle distribution were monitored using flow cytometry. In addition, Western blot analysis was used to evaluate the level of caspase-3 expression. In vivo examination of the inhibition of the size of tumors in nude mice treated with spider venom was measured. Results: Marked morphological changes were observed using AO/EB staining, SEM and TEM assay. Spider venom at concentrations of 10-40 mg/L caused dose- and time-dependent inhibition of HeLa cell proliferation.The ratio of apoptosis and necrosis increased. The activity of caspase-3 was upregulated after spider venom treatment. In vivo study of tumor size revealed that tumors significantly decreased in size from controls to tumors treated for 3 weeks with spider venom (P<0.05). Conclusion: The inhibition of HeLa cells by the venom of the spider Macrothele raveni was carried out in three ways: induction of apoptosis, necrosis of toxicity damage and direct lysis. Spider venom is a novel anti-tumor material both in vitro and in vivo.

  17. A distinct subset of self-renewing human memory CD8+ T cells survives cytotoxic chemotherapy

    OpenAIRE

    Turtle, Cameron J.; Swanson, Hillary M.; Fujii, Nobuharu; Estey, Elihu H.; Riddell, Stanley R.

    2009-01-01

    The mechanisms that maintain human T cell memory during normal and perturbed homeostasis are not fully understood. The repeated induction of profound lymphocytopenia in patients undergoing multiple cycles of cytotoxic chemotherapy infrequently results in severe infections with viruses controlled by memory T cells, suggesting that some memory T cells survive chemotherapy and restore immunity. Here we identify a distinct subpopulation of memory CD8+ T cells with the ability to rapidly efflux an...

  18. Deoxynivalenol induces cytotoxicity and genotoxicity in animal primary cell culture.

    Science.gov (United States)

    Singh, Shweta; Banerjee, Subham; Chattopadhyay, Pronobesh; Borthakur, Sashin Kumar; Veer, Vijay

    2015-03-01

    Deoxynivalenol (DON), a mycotoxin produced by Fusarium graminearum, is widely found as a contaminant of food. DON is responsible for a wide range of toxic activities, including gastro-intestinal, lymphoid, bone-marrow and cardiotoxicity. But, the complete explorations of toxicity in terms of hepatotoxicity, nephrotoxicity, cytotoxicity and genotoxicity as well have not been documented well. Again, the mechanisms through which DON damages the DNA and promotes cellular toxicity are not well established. Considering the above fact, this research article is focused on the effects of DON-induced toxicities on experimental animal model as well as its effects on cellular level via various toxicological investigations. DON treatment showed cytotoxicity and DNA damage. Further, flow cytometric analysis of hepatocytes showed cellular apoptosis, suggesting that DON-induced hepatotoxicity is, may be partly, mediated by apoptosis. Moreover, significant differences were found in each haematology and clinical chemistry value, either (p > 0.05). No abnormality of any organ was found during histopathological examination. Hence, it can be concluded that DON induces oxidative DNA damage and increases the formation of centromere positive micronuclei due to aneugenic activity. PMID:25578892

  19. Increased betulinic acid induced cytotoxicity and radiosensitivity in glioma cells under hypoxic conditions

    Directory of Open Access Journals (Sweden)

    Paschke Reinhard

    2011-09-01

    Full Text Available Abstract Background Betulinic acid (BA is a novel antineoplastic agent under evaluation for tumor therapy. Because of the selective cytotoxic effects of BA in tumor cells (including gliomas, the combination of this agent with conservative therapies (such as radiotherapy and chemotherapy may be useful. Previously, the combination of BA with irradiation under hypoxic conditions had never been studied. Methods In this study, the effects of 3 to 30 μM BA on cytotoxicity, migration, the protein expression of PARP, survivin and HIF-1α, as well as radiosensitivity under normoxic and hypoxic conditions were analyzed in the human malignant glioma cell lines U251MG and U343MG. Cytotoxicity and radiosensitivity were analyzed with clonogenic survival assays, migration was analyzed with Boyden chamber assays (or scratch assays and protein expression was examined with Western blot analyses. Results Under normoxic conditions, a half maximal inhibitory concentration (IC50 of 23 μM was observed in U251MG cells and 24 μM was observed in U343MG cells. Under hypoxic conditions, 10 μM or 15 μM of BA showed a significantly increased cytotoxicity in U251MG cells (p = 0.004 and p = 0.01, respectively and U343MG cells (p Conclusion Our results suggest that BA is capable of improving the effects of tumor therapy in human malignant glioma cells, particularly under hypoxic conditions. Further investigations are necessary to characterize its potential as a radiosensitizer.

  20. Cytotoxic Activity and Antiproliferative Effects of Crude Skin Secretion from Physalaemus nattereri (Anura: Leptodactylidae on in vitro Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Andréa Cruz e Carvalho

    2015-10-01

    Full Text Available Anuran secretions are rich sources of bioactive molecules, including antimicrobial and antitumoral compounds. The aims of this study were to investigate the therapeutic potential of Physalaemus nattereri skin secretion against skin cancer cells, and to assess its cytotoxic action mechanisms on the murine melanoma cell line B16F10. Our results demonstrated that the crude secretion reduced the viability of B16F10 cells, causing changes in cell morphology (e.g., round shape and structure shrinkage, reduction in mitochondrial membrane potential, increase in phosphatidylserine exposure, and cell cycle arrest in S-phase. Together, these changes suggest that tumor cells die by apoptosis. This skin secretion was also subjected to chromatographic fractioning using RP-HPLC, and eluted fractions were assayed for antiproliferative and antibacterial activities. Three active fractions showed molecular mass components in a range compatible with peptides. Although the specific mechanisms causing the reduced cell viability and cytotoxicity after the treatment with crude secretion are still unknown, it may be considered that molecules, such as the peptides found in the secretion, are effective against B16F10 tumor cells. Considering the growing need for new anticancer drugs, data presented in this study strongly reinforce the validity of P. nattereri crude secretion as a rich source of new anticancer molecules.

  1. 双胰腺癌相关抗原RNA转染树突细胞诱导特异性抗癌免疫反应的实验研究%Induction of specific immune cytotoxic T lymphocyte responses against pancreatic cancer by transfected dendritic cells with MUC4 and Survivin mRNA in vitro

    Institute of Scientific and Technical Information of China (English)

    陈江; 郭晓钟; 李宏宇; 邵晓东; 许文达

    2014-01-01

    Objective To investigate the induction of specific anti-tumor immune response induced by MUC4 and Survivin mRNA co-transfected dendritic cells (DCs) to provide the experimental evidences for the treatment of human pancreatic cancer with multi-epitope loaded DC vaccine. Methods DCs were isolated and cultured from peripheral blood mononuclear cells (PBMCs). After being transcripted and amplified, MUC4 and Survivin mRNA were co-transfected into DCs by electroporation. The expression of MUC4 and Survivin in DCs were detected by Western blot. The survival rate of transfected DCs were determined by MTT method. The induction of specific CTL activation by MUC4 and Survivin mRNA co-transfected DCs were evaluated through testing released IFN-γ by ELISA method. The induction of specific cytotoxic T lymphocyte (CTL) re-sponse by MUC4 and Survivin mRNA co-transfected DCs were measured by 51Cr standard cytotoxicity test. Results After MUC4 and Survivin mRNA co-transfection for 72 hours, the expression amount of MUC4 and Survivin were lower than the expression amount of MUC4 or Survivin individually. Compared with the MUC4 or Survivin mRNA individual transfected DCs, the IFN-γreleased in 24 hours by CTLs stimulated with MUC4 and Survivin mRNA co-transfection DCs were (33.84 ± 3.51)U/ml which was significantly higher than the amount of (21.87 ± 4.12)U/ml by MUC4 or (16.61 ± 2.09)U/ml by Survivin mRNA individually (P < 0.05). DCs co-transfection with MUC4 and Survivin mRNA could effectively induce HLA-A2 +/MUC4+/Survivin + specific CTL immune responses against pancreatic cancer cells in vitro. Conclusion The induction of CTLs by DCs co-transfected with human pancreatic cancer MUC4 and Survivin mRNA could produce more powerful specific anti-tumor immunity than single antigen loaded DCs.%目的:研究人胰腺癌MUC4与Survivin mRNA联合转染树突细胞(DC)诱导的特异性抗肿瘤免疫反应,为构建负载多抗原表位DC疫苗治疗胰腺癌提供实验依据

  2. T cell-mediated cytotoxicity against p53-protein derived peptides in bulk and limiting dilution cultures of healthy donors

    DEFF Research Database (Denmark)

    Röpke, M; Regner, M; Claesson, M H;

    1995-01-01

    -I restricted epitopes for T cell recognition and p53-derived peptides have been suggested as targets for tumour-specific cytotoxic T lymphocytes (CTL). Our primary aim was to estimate the frequencies of p53-peptide reactive CTL precursors (CTLp) in peripheral blood from healthy young individuals. We selected...... wild type and mutated peptides derived from the p53 sequence with a binding motif for HLA-A2.1 molecules. Peripheral blood mononuclear cells (PBMC) from healthy HLA-A2 donors were stimulated in vitro in bulk cultures as well as in limiting dilution cultures using autologous cells pulsed with p53...... peptides as stimulator cells. T cell reactivity was observed towards both wild type and mutated p53 peptide epitopes with CTL precursor frequencies varying from 1:2 x 10(4) to 1:1.5 x 10(5). These results might suggest the presence of an ongoing immune response in normal individuals against cells...

  3. Screening ToxCast™ Phase I Chemicals in a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay

    Science.gov (United States)

    An Adherent Cell Differentiation and Cytotoxicity (ACDC) in vitro assay with mouse embryonic stem cells was used to screen the ToxCast Phase I chemical library for effects on cellular differentiation and cell number. The U.S. Environmental Protection Agency (EPA) established the ...

  4. A Leukocyte Immune-Type Receptor Subset Is a Marker of Antiviral Cytotoxic Cells in Channel Catfish, Ictalurus punctatus.

    Science.gov (United States)

    Taylor, Erin B; Moulana, Mohadetheh; Stuge, Tor B; Quiniou, Sylvie M A; Bengten, Eva; Wilson, Melanie

    2016-03-15

    Channel catfish, Ictalurus punctatus, leukocyte immune type receptors (LITRs) represent a multigene family that encodes Ig superfamily proteins that mediate activating or inhibitory signaling. In this study, we demonstrate the use of mAb CC41 to monitor viral cytotoxic responses in catfish and determine that CC41 binds to a subset of LITRs on the surface of catfish clonal CTLs. Homozygous gynogenetic catfish were immunized with channel catfish virus (CCV)-infected MHC-matched clonal T cells (G14D-CCV), and PBL were collected at various times after immunization for flow cytometric analyses. The percentage of CC41(+) cells was significantly increased 5 d after primary immunization with G14D-CCV and at 3 d after a booster immunization as compared with control fish only injected with G14D. Moreover, CC41(+) cells magnetically isolated from the PBL specifically killed CCV-infected targets as measured by (51)Cr release assays and expressed messages for CD3γδ, perforin, and at least one of the CD4-like receptors as analyzed by RNA flow cytometry. When MLC effector cells derived from a G14D-CCV-immunized fish were preincubated with CC41 mAb, killing of G14D-CCV targets was reduced by ∼40%, suggesting that at least some LITRs have a role in target cell recognition and/or cytotoxicity. The availability of a LITR-specific mAb has allowed, to our knowledge for the first time, functional characterization of LITRs in an autologous system. In addition, the identification of an LITR subset as a cytotoxic cell marker will allow for more effective monitoring of catfish immune responses to pathogens. PMID:26856701

  5. Size-dependent cytotoxicity of europium doped NaYF{sub 4} nanoparticles in endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shizhu; Zhang, Cuimiao; Jia, Guang; Duan, Jianlei; Wang, Shuxiang, E-mail: wsx@hbu.edu.cn; Zhang, Jinchao, E-mail: jczhang6970@163.com

    2014-10-01

    Lanthanide-doped sodium yttrium fluoride (NaYF{sub 4}) nanoparticles exhibit novel optical properties which make them be widely used in various fields. The extensive applications increase the chance of human exposure to these nanoparticles and thus raise deep concerns regarding their riskiness. In the present study, we have synthesized europium doped NaYF{sub 4} (NaYF{sub 4}:Eu{sup 3+}) nanoparticles with three diameters and used endothelial cells (ECs) as a cell model to explore the potential toxic effect. The cell viability, cytomembrane integrity, cellular uptake, intracellular localization, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), apoptosis detection, caspase-3 activity and expression of inflammatory gene were studied. The results indicated that these nanoparticles could be uptaken into ECs and decrease the cell viability, induce the intracellular lactate dehydrogenase (LDH) release, increase the ROS level, and decrease the cell MMP in a size-dependent manner. Besides that, the cells were suffered to apoptosis with the caspase-3 activation, and the inflammation specific gene expressions (ICAM1 and VCAM1) were also increased. Our results suggest that the damage pathway may be related to the ROS generation and mitochondrial damage. The results provide novel evidence to elucidate their toxicity mechanisms and may be helpful for more rational applications of these compounds in the future. - Highlights: • NaYF{sub 4}:Eu{sup 3+} nanoparticles with three diameters have been synthesized. • NaYF{sub 4}:Eu{sup 3+} nanoparticles could be uptaken by endothelial cells (ECs). • NaYF{sub 4}:Eu{sup 3+} nanoparticles show a significant cytotoxicity on ECs. • The size of NaYF{sub 4}:Eu{sup 3+} nanoparticles may be important to their toxicology effect.

  6. Synthesis and cytotoxicity evaluation of 4-amino-4-dehydroxylarctigenin derivatives in glucose-starved A549 tumor cells.

    Science.gov (United States)

    Lei, Min; Gan, Xianwen; Zhao, Kun; Yu, Qiang; Hu, Lihong

    2015-02-01

    The natural product arctigenin (ATG) demonstrated preferential cytotoxicity to cancer cells under glucose starvation. A series of 4-amino-4-dehydroxylarctigenin derivatives based on lead compound ATG were designed and synthesized by bioisosteric modifications. Their cytotoxicities were evaluated in glucose-starved A549 tumor cells and the results indicated that the 4-amino-4-dehydroxylarctigenin showed more potent cytotoxicity than arctigenin, and the further substituent group on 4-amino would result in the cytotoxicities decreased significantly. 4-Substituted-arctigenin could selectively target on glucose-starved A549 tumor cells which provide an alternative strategy for anticancer drug development with minimal normal tissue toxicity. PMID:25571795

  7. Cytotoxicity evaluation of carbon-encapsulated iron nanoparticles in melanoma cells and dermal fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Grudzinski, Ireneusz P., E-mail: ireneusz.grudzinski@wum.edu.pl [Medical University of Warsaw, Department of Toxicology, Faculty of Pharmacy (Poland); Bystrzejewski, Michal [Warsaw University, Department of Physical Chemistry, Faculty of Chemistry (Poland); Cywinska, Monika A.; Kosmider, Anita [Medical University of Warsaw, Department of Toxicology, Faculty of Pharmacy (Poland); Poplawska, Magdalena [Warsaw University of Technology, Department of Organic Chemistry, Faculty of Chemistry (Poland); Cieszanowski, Andrzej [Medical University of Warsaw, Department of Clinical Radiology, Faculty of Medicine (Poland); Ostrowska, Agnieszka [Analytic Centre, University of Life Sciences SGGW (Poland)

    2013-08-15

    Carbon-encapsulated iron nanoparticles (CEINs) are emerging as promising biomedical tools due to their unique physicochemical properties. In this study, the cytotoxic effect of CEINs (the mean diameter distribution ranges 46-56 nm) has been explored by MTT, LDH leakage, Calcein-AM/propidium iodide (PI) and Annexin V-FITC/PI assays in human melanoma (HTB-140), mouse melanoma (B16-F10) cells, and human dermal fibroblasts (HDFs). The results demonstrated that CEINs produce mitochondrial and cell membrane cytotoxicities in a dose (0.0001-100 {mu}g/ml)-dependent manner. Moreover, the studies elucidated some differences in cytotoxic effects between CEINs used as raw and purified materials composing of the carbon surface with acidic groups. Experiments showed that HTB-140 cells are more sensitive to prone early apoptotic events due to raw CEINs as compared to B16-F10 or HDF cells, respectively. Taken together, these results suggest that the amount of CEINs administered to cells and the composition of CEINs containing different amounts of iron as well as the carbon surface modification type is critical determinant of cytotoxic responses in both normal and cancer (melanoma) cells.

  8. Cytotoxic Effects of Hydroxylated Fullerenes in Three Types of Liver Cells

    Directory of Open Access Journals (Sweden)

    Yoshiaki Ikarashi

    2013-07-01

    Full Text Available Fullerenes C60 have attracted considerable attention in the biomedical field due to their interesting properties. Although there has been a concern that C60 could be metabolized to hydroxylated fullerenes (C60(OHx in vivo, there is little information on the effect of hydroxylated C60 on liver cells. In the present study, we evaluated the cytotoxic effects of fullerene C60 and various hydroxylated C60 derivatives, C60(OH2, C60(OH6–12, C60(OH12 and C60(OH36, with three different types of liver cells, dRLh-84, HepG2 and primary cultured rat hepatocytes. C60, C60(OH2 and C60(OH36 exhibited little or no cytotoxicity in all of the cell types, while C60(OH6–12 and C60(OH12 induced cytotoxic effects in dRLh-84 cells, accompanied by the appearance of numerous vacuoles around the nucleus. Moreover, mitochondrial activity in liver cells was significantly inhibited by C60(OH6–12 and C60(OH12. These results indicate that the number of hydroxyl groups on C60(OHx contribute to the difference of their cytotoxic potential and mitochondrial damage in liver cells.

  9. Cytotoxicity evaluation of carbon-encapsulated iron nanoparticles in melanoma cells and dermal fibroblasts

    International Nuclear Information System (INIS)

    Carbon-encapsulated iron nanoparticles (CEINs) are emerging as promising biomedical tools due to their unique physicochemical properties. In this study, the cytotoxic effect of CEINs (the mean diameter distribution ranges 46–56 nm) has been explored by MTT, LDH leakage, Calcein-AM/propidium iodide (PI) and Annexin V-FITC/PI assays in human melanoma (HTB-140), mouse melanoma (B16-F10) cells, and human dermal fibroblasts (HDFs). The results demonstrated that CEINs produce mitochondrial and cell membrane cytotoxicities in a dose (0.0001–100 μg/ml)-dependent manner. Moreover, the studies elucidated some differences in cytotoxic effects between CEINs used as raw and purified materials composing of the carbon surface with acidic groups. Experiments showed that HTB-140 cells are more sensitive to prone early apoptotic events due to raw CEINs as compared to B16-F10 or HDF cells, respectively. Taken together, these results suggest that the amount of CEINs administered to cells and the composition of CEINs containing different amounts of iron as well as the carbon surface modification type is critical determinant of cytotoxic responses in both normal and cancer (melanoma) cells

  10. Integrin Receptors on Tumor Cells Facilitate NK cell-mediated Antibody-dependent Cytotoxicity

    OpenAIRE

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J.; Powers, Gordon D.; Sato, Takami; Campbell, Kerry S.; Sykulev, Yuri

    2014-01-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high anti...

  11. Dynamics of mercury, cadmium and vanadium in cultured bovine kidney cells: an examination of relationships to cytotoxicity and cell function

    International Nuclear Information System (INIS)

    The objective of this study was to partially define the in vitro cellular response to mercury, cadmium and vanadium insult. A bovine kidney cell line served as the model system for examining the relationship of the cellular dynamics of metal accumulation and distribution to cytotoxicity. Additionally, biochemical marker functions were monitored in surviving cells to determine the importance of metal uptake and distribution to cell functionality. Each metal (HgCl2, CdCl2, and Na3VO4) elicited a concentration-related cytotoxicity which was correlated to the cellular metal burden. Multiphasic accumulation kinetics were established for mercury and vanadium; cadmium was accumulated in a linear fashion. Subcellular metal distribution was independent of both the extra-cellular metal concentration and the degree of cytotoxicity. Biochemical marker functions indicated a toxicity-related decrease in cell functionality in surviving cells for all metals

  12. Melanoma cell lysosome secretory burst neutralizes the CTL-mediated cytotoxicity at the lytic synapse

    Science.gov (United States)

    Khazen, Roxana; Müller, Sabina; Gaudenzio, Nicolas; Espinosa, Eric; Puissegur, Marie-Pierre; Valitutti, Salvatore

    2016-01-01

    Human melanoma cells express various tumour antigens that are recognized by CD8+ cytotoxic T lymphocytes (CTLs) and elicit tumour-specific responses in vivo. However, natural and therapeutically enhanced CTL responses in melanoma patients are of limited efficacy. The mechanisms underlying CTL effector phase failure when facing melanomas are still largely elusive. Here we show that, on conjugation with CTL, human melanoma cells undergo an active late endosome/lysosome trafficking, which is intensified at the lytic synapse and is paralleled by cathepsin-mediated perforin degradation and deficient granzyme B penetration. Abortion of SNAP-23-dependent lysosomal trafficking, pH perturbation or impairment of lysosomal proteolytic activity restores susceptibility to CTL attack. Inside the arsenal of melanoma cell strategies to escape immune surveillance, we identify a self-defence mechanism based on exacerbated lysosome secretion and perforin degradation at the lytic synapse. Interfering with this synaptic self-defence mechanism might be useful in potentiating CTL-mediated therapies in melanoma patients. PMID:26940455

  13. The best time of cytotoxicity for extracted cell wall from Lactobacillus casei and paracasei in K562 cell line

    Directory of Open Access Journals (Sweden)

    Riki M

    2013-02-01

    Full Text Available Background: The aim of this study was to evaluate the effect of extracted cell walls from Lactobacillus casei and Lactobacillus paracasei as probiotic bacteria (isolated from common carp intestine on K562 and the role of cell concentration on the results of MTT [3-(4,5-Dimethylthiazol-2-yl2,5- Diphenyl tetrazolium Bromide] test.Methods: For this purpose, bacteria were cultured in specific medium (MRS broth at anaerobic condition for 24-48 hour. After incubation period culture medium was centri-fuged, then the cells were washed twice with PBS buffer to remove additional medium. Finally, collected bacterial cell disrupted by Sonication and cell walls were separated from other components by centrifugation. After that, different concentrations of cell walls (500, 1000, 2000 and 4000 µg/ml were prepared in RPMI medium for each bacteria, separately. Then anticancer properties of the cell walls were determined in vitro at 12, 24, 48 and 72 h, also the effect of K562 concentration was assayed with MTT technique.Results: The results showed extracted cell wall from both probiotic statistically (P=0.098 have anti turmeric properties in K562 and their properties will arise in relation with concentration. As well as, we found that the number of cell had not any affect on the result of MTT assay.Conclusion: We conclude that the cytotoxicity property of extracted cell wall is related in the type of bacteria, but this anticancer property would warrant further study on the clinical application of extracted cell wall.

  14. Evaluation of Cytotoxicity of Sagebrush Plain Extract on Human Breast Cancer MCF7 Cells

    Directory of Open Access Journals (Sweden)

    B Gordanian

    2013-07-01

    Full Text Available Abstract Background & aim: Several studies have reported anti-cancer properties of sagebrush plain. The aim of this study was to evaluate the cytotoxicity of the methanol extract of sagebrush plain on human breast cancer MCF7 cells. Methods: In the present experimental study, the toxic effects of methanol extracts of flowers, leaves, stems and roots of sagebrush plain from of Khorassan and Esfahan province were tested on human breast cancer cells MCF-7 and normal cells HEK293 . Plant samples were extracted by methanol and their toxic effects on normal and breast cancer cells at concentrations of 5.62, 125, 250 and 500 µg/ml was determined by MTT. Both breast cancer cells MCF-7 and normal HEK293 cells were cultured in RPMI-1640 medium and DMEM containing 10% fetal calf serums were cultured. Data were analyzed by one-way ANOVA. Results: The methanol extract of sagebrush showed toxicity on MCF7 cells. The extract of Khorasan showed higher toxicity than Esfahan province. IC50 of sagebrush plant for all parts of the plant were obtained more than 500 µg/ml, but the IC50 of sagebrush plant of Khorasan region in leaf and flower were 205 ± 1.3 and 213 ± 5.3µg respectively. The leaves and flowers in both cases had the highest cytotoxicity. Plant extracts in both regions did not show significant cytotoxicity on normal HEK293 cells. Conclusion: The extract of the sagebrush plain region of Khorasan region showed greater cytotoxicity than Esfahan. It seems that different environmental conditionshas considerable cytotoxicity. Keywords: Sagebrush Plain, MTT, Breast Cancer

  15. Synthesis and Selective Cytotoxic Activities on Rhabdomyosarcoma and Noncancerous Cells of Some Heterocyclic Chalcones.

    Science.gov (United States)

    Do, Tuong-Ha; Nguyen, Dai-Minh; Truong, Van-Dat; Do, Thi-Hong-Tuoi; Le, Minh-Tri; Pham, Thanh-Quan; Thai, Khac-Minh; Tran, Thanh-Dao

    2016-01-01

    Chemically diverse heterocyclic chalcones were prepared and evaluated for cytotoxicity, aiming to push forward potency and selectivity. They were tested against rhabdomyosarcoma (RMS) and noncancerous cell line (LLC-PK1). The influence of heteroaryl patterns on rings A and B was studied. Heterocycle functionalities on both rings, such as phenothiazine, thiophene, furan and pyridine were evaluated. Notably, the introduction of three methoxy groups at positions 3, 4, 5 on ring B appears to be critical for cytotoxicity. The best compound, with potent and selective cytotoxicity (IC50 = 12.51 μM in comparison with the value 10.84 μM of paclitaxel), contains a phenothiazine moiety on ring A and a thiophene heterocycle on ring B. Most of the potential compounds only show weak cytoxicity on the noncancerous cell line LLC-PK1. PMID:27005608

  16. Synthesis and Selective Cytotoxic Activities on Rhabdomyosarcoma and Noncancerous Cells of Some Heterocyclic Chalcones

    Directory of Open Access Journals (Sweden)

    Tuong-Ha Do

    2016-03-01

    Full Text Available Chemically diverse heterocyclic chalcones were prepared and evaluated for cytotoxicity, aiming to push forward potency and selectivity. They were tested against rhabdomyosarcoma (RMS and noncancerous cell line (LLC-PK1. The influence of heteroaryl patterns on rings A and B was studied. Heterocycle functionalities on both rings, such as phenothiazine, thiophene, furan and pyridine were evaluated. Notably, the introduction of three methoxy groups at positions 3, 4, 5 on ring B appears to be critical for cytotoxicity. The best compound, with potent and selective cytotoxicity (IC50 = 12.51 μM in comparison with the value 10.84 μM of paclitaxel, contains a phenothiazine moiety on ring A and a thiophene heterocycle on ring B. Most of the potential compounds only show weak cytoxicity on the noncancerous cell line LLC-PK1.

  17. Cytotoxicity evaluation of Ziziphus mauritiana and Oenanthe javanica on Chang liver cell lines

    International Nuclear Information System (INIS)

    Ziziphus mauritiana and Oenanthe javanica which are known as bidara and selom have various uses in traditional medicine. The leaves of bidara are helpful in liver disease, asthma, spiritual treatment and fever whereas selom has been widely used to treat fever, abdominal pain, leucorrhea, and urinary problems. Even though these plants have been widely used as traditional remedy, no cytotoxic evaluation has been carried out. In this study, cytotoxicity activity of both plants was evaluated in vitro against Chang liver cells using methyl thiazolyl tetrazolium (MTT) assay method. The IC50 value obtained for Ziziphus mauritiana methanolic extract and Oenanthe javanica aqueous extract were 17.23 mg/ ml and 28.13mg/ ml, respectively. This result illustrated that both plants did not produce any cytotoxic effect against Chang liver cells and considered to be toxicological safe to be taken by human for medicinal purposes. (author)

  18. MUC1-specific cytotoxic T lymphocytes eradicate tumors when adoptively transferred in vivo.

    Science.gov (United States)

    Mukherjee, P; Ginardi, A R; Tinder, T L; Sterner, C J; Gendler, S J

    2001-03-01

    We have reported previously that MUC1 transgenic mice with spontaneous tumors of the pancreas (designated MET) naturally develop MHC class I-restricted, MUC1-specific CTLs as tumors progress (P. Mukherjee et al., J. Immunol., 165: 3451-3460, 2000). From these MET mice, we have isolated, expanded, and cloned naturally occurring MUC1-specific CTLs in vitro. In this report, we show that the CTL line is predominantly CD8+ T cells and expresses T-cell receptor Vbeta chains 5.1/5.2, 11, 13, and 2 and Valpha chains 2, 8.3, 3.2, and 11.1/11.2. These CTLs recognize several epitopes on the MUC1 tandem repeat with highest affinity to APGSTAPPA. The CTL clone, on the other hand, is 100% CD8+ cells and expresses a single Vbeta chain of 5.1/5.2 and Valpha2. It recognizes only the H-2Db class I-restricted epitope of MUC1, APGSTAPPA. When adoptively transferred, the CTLs were effective in eradicating MUC1-expressing injected tumor cells including mammary gland cells (C57mg) and B16 melanomas. These results suggest that MUC1-specific CTLs are capable of possibly preventing, or at least substantially delaying, MUC1-expressing tumor formation. To our knowledge, this is the first evidence that demonstrates that the naturally occurring MUC1-specific CTLs isolated from one tumor model has antitumor effects on other MUC1-expressing tumors in vivo. Therefore, our data confirm that MUC1 is an important tumor rejection antigen and can serve as a target for immunotherapy. PMID:11300482

  19. Selective induction of apoptosis by the cytotoxic analog AN-207 in cells expressing recombinant receptor for luteinizing hormone-releasing hormone

    OpenAIRE

    Danila, Daniel C; Schally, Andrew V.; Nagy, Attila; Alexander, Joseph M

    1999-01-01

    The selectivity of ligands specific for certain cells can be used to preferentially target chemotherapeutic compounds to neoplastic cells. Human breast, ovarian, endometrial, and prostatic cancers express receptors that can mediate the delivery of targeted cytotoxic compounds to neoplastic cells. Recently, a potent derivative of 2-pyrrolinodoxorubicin (AN-201) conjugated to [d-Lys6] luteinizing hormone-releasing hormone (LH-RH) (AN-207), was demonstrated to be less toxic than the nonconjugate...

  20. Cellular distribution of inorganic mercury and its relation to cytotoxicity in bovine kidney cell cultures

    International Nuclear Information System (INIS)

    A bovine kidney cell culture system was used to assess what relationship mercuric chloride (HgCl2) uptake and subcellular distribution had to cytotoxicity. Twenty-four-hour incubations with 0.05-50 μM HgCl2 elicited a concentration-related cytotoxicity. Cellular accumulation of 203Hg was also concentration-related, with 1.0 nmol/106 cells at the IC50. Measurement of Hg uptake over the 24-h exposure period revealed a multiphasic process. Peak accumulation was attained by 1 h and was followed by extrusion and plateauing of intracellular Hg levels. Least-squares regression analysis of the cytotoxicity and cellular uptake data indicated a potential relationship between the Hg uptake and cytotoxicity. However, the subcellular distribution of Hg was not concentration-related. Mitochondria and soluble protein fractions accounted for greater than 65% of the cell-associated Hg at all concentrations. The remaining Hg was distributed between the microsomal (6-10%) and nuclear and cell debris (11-22%) fractions at all concentrations tested. Less than 20% of the total cell-associated Hg was bound with metallothionein-like protein. 31 references, 4 figures, 3 tables

  1. Dendrimer-curcumin conjugate: a water soluble and effective cytotoxic agent against breast cancer cell lines.

    Science.gov (United States)

    Debnath, Shawon; Saloum, Darin; Dolai, Sukanta; Sun, Chong; Averick, Saadyah; Raja, Krishnaswami; Fata, Jimmie E

    2013-12-01

    Curcumin, which is derived from the plant Curcuma longa, has received considerable attention as a possible anti-cancer agent. In cell culture, curcumin is capable of inducing apoptosis in cancer cells at concentrations that do not affect normal cells. One draw-back holding curcumin back from being an effective anti-cancer agent in humans is that it is almost completely insoluble in water and therefore has poor absorption and subsequently poor bioavailability. Here we have generated a number of curcumin derivatives (tetrahydro-curcumin, curcumin mono-carboxylic acid, curcumin mono-galactose, curcumin mono-alkyne and dendrimer-curcumin conjugate) to test whether any of them display both cytotoxicity and water solubility. Of those tested only dendrimer-curcumin conjugate exhibited both water solubility and cytotoxicity against SKBr3 and BT549 breast cancer cells. When compared to curcumin dissolved in DMSO, dendrimer-curcumin conjugate dissolved in water was significantly more effective in inducing cytotoxicity, as measured by the MTT assay and effectively induced cellular apoptosis measured by caspase-3 activation. Since dendrimer-curcumin conjugate is water soluble and capable of inducing potent cytotoxic effects on breast cancer cell lines, it may prove to be an effective anti-cancer therapy to be used in humans. PMID:23387971

  2. Cytotoxicity and genotoxicity of intravitreal adalimumab administration in rabbit retinal cells

    Directory of Open Access Journals (Sweden)

    Álcio Coutinho de Paula

    2015-04-01

    Full Text Available Purpose: To assess the cytotoxicity and genotoxicity of intravitreal adalimumab treatment in an animal experimental model using cytological and molecular techniques. Methods: Eighteen rabbits were randomly assigned to three groups: control, adalimumab treatment, and placebo. Cytotoxicity on retinal cells was evaluated using flow cytometry assays to determine the level of apoptosis and necrosis. Genotoxicity was evaluated by comet assays to assess DNA damage, and quantitative real-time polymerase chain reaction (qPCR was used to evaluate expression of apoptosis-inducing caspases (8 and 3. Results: No cytotoxicity or genotoxicity was observed in any of the two treatment groups (adalimumab and placebo following intravitreal administration compared with the control group. Flow cytometry analysis revealed that more than 90% of the cells were viable, and only a low proportion of retinal cells presented apoptotic (~10% or necrotic (<1% activity across all groups. Molecular damage was also low with a maximum of 6.4% DNA degradation observed in the comet assays. In addition, no increase in gene expression of apoptosis-inducing caspases was observed on retinal cells by qPCR in both the adalimumab and placebo groups compared with the control group. Conclusion: The use of adalimumab resulted in no detectable cytotoxicity or genotoxicity on retinal cells for up to 60 days upon administration. These results therefore indicate that adalimumab may be a safe option for intravitreal application to treat ocular inflammatory diseases in which TNF-α is involved.

  3. Differential cytotoxic effects of arsenic on human and animal cells.

    OpenAIRE

    Lee, T C; Ho, I C

    1994-01-01

    Human fibroblasts (HFW) were 10-fold more susceptible than Chinese hamster ovary (CHO-K1) cells to sodium arsenite. Comparison of cellular antioxidant enzyme activities showed that CHO-K1 cells contained 3- and 8-fold more glutathione-peroxidase and catalase activities, respectively, than HFW cells. Since vitamin E, methylamine, and benzyl alcohol could prevent, in part, the arsenite-induced killing of HFW cells, we suggest that arsenite can induce oxidative damage in HFW cells. We have also ...

  4. Genipin-induced inhibition of uncoupling protein-2 sensitizes drug-resistant cancer cells to cytotoxic agents.

    Directory of Open Access Journals (Sweden)

    Ryan J Mailloux

    Full Text Available Uncoupling protein-2 (UCP2 is known to suppress mitochondrial reactive oxygen species (ROS production and is employed by drug-resistant cancer cells to mitigate oxidative stress. Using the drug-sensitive HL-60 cells and the drug-resistant MX2 subline as model systems, we show that genipin, a UCP2 inhibitor, sensitizes drug-resistant cells to cytotoxic agents. Increased MX2 cell death was observed upon co-treatment with genipin and different doses of menadione, doxorubicin, and epirubicin. DCFH-DA fluorimetry revealed that the increase in MX2 cell death was accompanied by enhanced cellular ROS levels. The drug-induced increase in ROS was linked to genipin-mediated inhibition of mitochondrial proton leak. State 4 and resting cellular respiratory rates were higher in the MX2 cells in comparison to the HL-60 cells, and the increased respiration was readily suppressed by genipin in the MX2 cells. UCP2 accounted for a remarkable 37% of the resting cellular oxygen consumption indicating that the MX2 cells are functionally reliant on this protein. Higher amounts of UCP2 protein were detected in the MX2 versus the HL-60 mitochondria. The observed effects of genipin were absent in the HL-60 cells pointing to the selectivity of this natural product for drug-resistant cells. The specificity of genipin for UCP2 was confirmed using CHO cells stably expressing UCP2 in which genipin induced an ∼22% decrease in state 4 respiration. These effects were absent in empty vector CHO cells expressing no UCP2. Thus, the chemical inhibition of UCP2 with genipin sensitizes multidrug-resistant cancer cells to cytotoxic agents.

  5. A Neutralizing Antibody Assay Based on a Reporter of Antibody-Dependent Cell-Mediated Cytotoxicity.

    Science.gov (United States)

    Wu, Yuling; Li, Jia J; Kim, Hyun Jun; Liu, Xu; Liu, Weiyi; Akhgar, Ahmad; Bowen, Michael A; Spitz, Susan; Jiang, Xu-Rong; Roskos, Lorin K; White, Wendy I

    2015-11-01

    Benralizumab is a humanized anti-IL5 receptor α (IL5Rα) monoclonal antibody (mAb) with enhanced (afucosylation) antibody-dependent cell-mediated cytotoxicity (ADCC) function. An ADCC reporter cell-based neutralizing antibody (NAb) assay was developed and characterized to detect NAb against benralizumab in human serum to support the clinical development of benralizumab. The optimal ratio of target cells to effector cells was 3:1. Neither parental benralizumab (fucosylated) nor benralizumab Fab resulted in ADCC activity, confirming the requirement for ADCC activity in the NAb assay. The serum tolerance of the cells was determined to be 2.5%. The cut point derived from normal and asthma serum samples was comparable. The effective range of benralizumab was determined, and 35 ng/mL [80% maximal effective concentration (EC80)] was chosen as the standard concentration to run in the assessment of NAb. An affinity purified goat anti-benralizumab polyclonal idiotype antibody preparation was shown to have NAb since it inhibited ADCC activity in a dose-dependent fashion. The low endogenous concentrations of IL5 and soluble IL5 receptor (sIL5R) did not demonstrate to interfere with the assay. The estimated assay sensitivities at the cut point were 1.02 and 1.10 μg/mL as determined by the surrogate neutralizing goat polyclonal and mouse monoclonal anti-drug antibody (ADA) controls, respectively. The assay can detect NAb (at 2.5 μg/mL) in the presence of 0.78 μg/mL benralizumab. The assay was not susceptible to non-specific matrix effects. This study provides an approach and feasibility of developing an ADCC cell-based NAb assay to support biopharmaceuticals with an ADCC function. PMID:26205082

  6. Non-synergistic cytotoxic effects of Fusarium and Alternaria toxin combinations in Caco-2 cells.

    Science.gov (United States)

    Vejdovszky, Katharina; Warth, Benedikt; Sulyok, Michael; Marko, Doris

    2016-01-22

    Exposure of humans and animals to mycotoxins via food and feed generally involves a conglomeration of compounds contaminating the consumed products. Investigations on combinatory effects of mycotoxins are therefore of great importance. In this study, cytotoxic effects of binary mixtures of the Fusarium toxins enniatin B, aurofusarin, deoxynivalenol, nivalenol and zearalenone, and tenuazonic acid produced by Alternaria spp., were evaluated by the WST-1 assay in the colorectal carcinoma cell-line Caco-2 after 24h of incubation. The selection of these mycotoxins was based on typically occurring natural contamination patterns in grains. Aurofusarin, which can be found abundantly in contaminated foodstuff and has not been toxicologically characterized properly so far, showed pronounced cytotoxicity, decreasing the mitochondrial activity at 10μM to 51% compared to a solvent control. Combinations of other mycotoxins with aurofusarin showed additive effects. In contrast, binary mixtures of enniatin B, deoxynivalenol, nivalenol and zearalenone at cytotoxic concentrations, predominantly resulted in antagonistic effects. Binary combinations of these four Fusarium toxins with tenuazonic acid also revealed interacting effects leading to a decrease in cytotoxicity, compared to expected combinatory effects. Especially in combination with deoxynivalenol, tenuazonic acid was found to significantly reduce the cytotoxicity of this mycotoxin in Caco-2 cells. Synergistic effects were not observed for any toxin combination under the chosen conditions. PMID:26529482

  7. Exogenous albumin inhibits sorafenib-induced cytotoxicity in human cancer cell lines

    OpenAIRE

    Kanno, Syu-ichi; ITOH, KATSUYUKI; Suzuki, Naoto; TOMIZAWA, AYAKO; Yomogida, Shin; ISHIKAWA, MASAAKI

    2012-01-01

    Sorafenib is an orally administered multikinase inhibitor that exhibits anti-angiogenic and anti-tumor activity. Sorafenib is also known to bind to protein (>99.5%), suggesting protein binding may be involved in sorafenib pharmacokinetic variability. Albumin is a major drug-binding protein. In this study, we examined the effect of albumin on sorafenib-induced cytotoxicity using two in vitro culture cell lines, human hepatoma Huh-7 cells and androgen-independent prostate cancer PC-3 cells. The...

  8. Mannose 6-, fructose 1-, and fructose 6-phosphates inhibit human natural cell-mediated cytotoxicity.

    OpenAIRE

    Forbes, J T; Bretthauer, R. K.; Oeltmann, T N

    1981-01-01

    In vitro human natural cell-mediated cytotoxicity (NCMC) to K-562, Molt-4, and F-265 cells is inhibited in a dose-dependent manner by mannose 6-phosphate, fructose 1-phosphate and fructose 6-phosphate. This inhibition is not observed with mannose, glucose, fucose, glucose 6-phosphate, mannose 1-phosphate, galactose 1-phosphate, or galactose 6-phosphate. Preincubation of the effector cells, obtained from fresh whole blood, with mannose-6-phosphate, fructose-1-phosphate, or fructose-6-phosphate...

  9. Rapid Ped-2E9 Cell-Based Cytotoxicity Analysis and Genotyping of Bacillus Species

    OpenAIRE

    Gray, Kristen M.; Banada, Padmapriya P.; O'Neal, Erin; Arun K. Bhunia

    2005-01-01

    Bacillus species causing food-borne disease produce multiple toxins eliciting gastroenteritis. Toxin assays with mammalian cell cultures are reliable but may take 24 to 72 h to complete and also lack sensitivity. Here, a sensitive and rapid assay was developed using a murine hybridoma Ped-2E9 cell model. Bacillus culture supernatants containing toxins were added to a Ped-2E9 cell line and analyzed for cytotoxicity with an alkaline phosphatase release assay. Most Bacillus cereus strains produc...

  10. Cytotoxicity and cell cycle effects of novel indolo[2,3-b]quinoline derivatives.

    Science.gov (United States)

    Humeniuk, Rita; Kaczmarek, Lukasz; Peczyńska-Czoch, Wanda; Marcinkowska, Ewa

    2003-01-01

    Cellular effects of novel indolo[2,3-b]quinoline derivatives were studied. These compounds are synthetic analogs of plant alkaloid neocryptolepine (5-methyl-5H-indolo[2,3-b]quinoline) present in extracts from Cryptolepis sanguinolenta. They are traditionally used in natural medicine in Central and West Africa. Previous molecular and computational studies indicated that these compounds were DNA intercalators and inhibitors of topoisomerase II. We have extended our studies on their mode of action to the cellular level. Past experiments have shown that these compounds were active in vitro against cell lines derived from solid tumors, so for the present studies we selected leukemic cell lines. Jurkat acute T cell, CCRF-CEM T lymphoblastoid, THP-1 acute monocytic, HL-60 acute promyelocytic leukemias, and HL-60/MX2 subline with reduced expression of topoisomerase II were used. We evaluated the cytotoxicity and cell cycle effects of the indolo[2,3-b]quinoline compounds. We also tested if these compounds were able to induce apoptosis in the cells. Our studies revealed that novel indolo[2,3-b]quinoline derivatives were more cytotoxic to all cell lines than etoposide (used as a reference topoisomerase II inhibitor), and that their cytotoxicity depended on the substituents introduced to the indolo[2,3-b]quinoline core. Surprisingly, our studies have shown that HL-60/MX2 cell line and also THP-1 cell line, resistant to etoposide, were susceptible to methyl- and methoxy-substituted indolo[2,3-b]quinoline derivatives. In parallel to the evaluation of cytotoxicity we studied cell cycle effects of these compounds. Treatment of HL-60 cells with etoposide in subcytotoxic concentrations resulted in a massive accumulation of the cells in the G2/M phase of the cell cycle. When we used subcytotoxic concentrations of our novel indolo[2,3-b]quinoline derivatives the cell cycle progression of HL-60 cells was not affected. Moreover, the cell cycle of HL-60/MX2 cells was not influenced by

  11. Cytotoxic effects and specific gene expression alterations induced by I-125-labeled triplex-forming oligonucleotides

    OpenAIRE

    Dahmen, Volker; Kriehuber, Ralf

    2012-01-01

    Purpose: Triplex-forming oligonucleotides (TFO) bind to the DNA double helix in a sequence-specific manner. Therefore, TFO seem to be a suitable carrier for Auger electron emitters to damage exclusively targeted DNA sequences, e.g., in tumor cells. We studied the influence of I-125 labeled TFO with regard to cell survival and induction of DNA double-strand breaks (DSB) using TFO with different genomic targets and target numbers. Furthermore, the ability of TFO to alter the gene expression of ...

  12. Immunoprophylaxis and cytotoxic effector cells against EL 4 leukemia induced in syngeneic C57BL/6J mice by use of irradiated EL 4 cells

    International Nuclear Information System (INIS)

    Tumor-specific immunoprophylaxis was achieved in C57BL/6J mice against EL 4 leukosis cell challenge by sensitization of the syngeneic host with multiple ip injections of irradiated EL 4 cells. A minimal radiation dose was used to replication-block EL 4 cells before inoculation, as defined by dose-response analysis of irradiated EL 4 cells. Multiple ip injections of irradiated EL 4 cells stimulated development of significant, yet relatively low, levels of cytotoxic lymphoid activity (CLA) in lymphoid cells of the peritoneal exudate as measured by in vitro 51Cr-release cytotoxicity assays. The specific temporal and frequency dependencies of the inoculation regimen for achieving immunoprophylaxis indicated that, in addition to CLA, other, short-lived, immune processes were important in the tumor rejection. These observations showed the capacity of the C57BL/6J host for tumor-specific immune recognition and rejection of the syngeneic EL 4 leukemia. The tumor rejection could be elicited solely by inoculations of irradiated EL 4 cells and did not require exogenous amplifiers, such as immunoadjuvants, chemical modifiers, and/or allogeneic immune information transfer. (auth)

  13. Natural killer cell cytotoxicity of breast cancer targets is enhanced by two distinct mechanisms of antibody-dependent cellular cytotoxicity against LFA-3 and HER2/neu.

    Science.gov (United States)

    Cooley, S; Burns, L J; Repka, T; Miller, J S

    1999-10-01

    Treatment of advanced breast cancer with autologous stem cell transplantation is limited by a high probability of disease relapse. In clinical trials, interleukin 2 (IL-2) alone can expand natural killer (NK) cells in vivo and increase their cytotoxic activity against breast cancer cell lines, but this increase is modest. Understanding the mechanisms that mediate NK cell lysis of breast cancer targets may lead to improvements of current immunotherapy strategies. NK cells from normal donors or patients receiving subcutaneous IL-2 were tested in cytotoxicity assays against five breast cancer cell lines. The role of adhesion molecules and antibodies that interact through Fc receptors on NK cells was explored. NK cell lysis of breast cancer targets is variable and is partially dependent on recognition through ICAM-1 and CD18. While blocking CD2 slightly decreased cytotoxicity, contrary to expectations, an antibody against CD58 (the ligand for CD2), failed to block killing and instead mediated an increased cytotoxicity that correlated with target density of CD58. The CD58 antibody-enhanced killing was dependent not only on FcRgammaIII but also on CD2 and ICAM-1/CD18. To further elucidate the mechanism of this CD58 antibody-dependent cellular cytotoxicity (ADCC), another antibody was tested. Trastuzumab (Herceptin), a humanized antibody against HER2/neu, mediated potent ADCC against all the HER2/neu positive breast cancer targets. Unlike CD58 antibody-mediated ADCC, Herceptin ADCC was minimally affected by blocking antibodies to CD2 or ICAM-1/CD18, which suggests a different mechanism of action. This study shows that multiple mechanisms are involved in NK cell lysis of breast cancer targets, that none of the targets are inherently resistant to killing, and that two distinct mechanisms of ADCC can target immunotherapy to breast cancer cells. PMID:10517495

  14. A biophysical model of cell evolution after cytotoxic treatments: Damage, repair and cell response.

    Science.gov (United States)

    Tomezak, M; Abbadie, C; Lartigau, E; Cleri, F

    2016-01-21

    We present a theoretical agent-based model of cell evolution under the action of cytotoxic treatments, such as radiotherapy or chemotherapy. The major features of cell cycle and proliferation, cell damage and repair, and chemical diffusion are included. Cell evolution is based on a discrete Markov chain, with cells stepping along a sequence of discrete internal states from 'normal' to 'inactive'. Probabilistic laws are introduced for each type of event a cell can undergo during its life: duplication, arrest, senescence, damage, reparation, or death. We adjust the model parameters on a series of cell irradiation experiments, carried out in a clinical LINAC, in which the damage and repair kinetics of single- and double-strand breaks are followed. Two showcase applications of the model are then presented. In the first one, we reconstruct the cell survival curves from a number of published low- and high-dose irradiation experiments. We reobtain a very good description of the data without assuming the well-known linear-quadratic model, but instead including a variable DSB repair probability. The repair capability of the model spontaneously saturates to an exponential decay at increasingly high doses. As a second test, we attempt to simulate the two extreme possibilities of the so-called 'bystander' effect in radiotherapy: the 'local' effect versus a 'global' effect, respectively activated by the short-range or long-range diffusion of some factor, presumably secreted by the irradiated cells. Even with an oversimplified simulation, we could demonstrate a sizeable difference in the proliferation rate of non-irradiated cells, the proliferation acceleration being much larger for the global than the local effect, for relatively small fractions of irradiated cells in the colony. PMID:26549470

  15. Protein-binding, cytotoxicity in vitro and cell cycle arrest of ruthenium(II) polypyridyl complexes

    Science.gov (United States)

    Liu, Si-Hong; Zhu, Jian-Wei; Xu, Hui-Hua; Wang, Yan; Liu, Ya-Min; Liang, Jun-Bo; Zhang, Gui-Qiang; Cao, Di-Hua; Lin, Yang-Yang; Wu, Yong; Guo, Qi-Feng

    2016-05-01

    The cytotoxic activity of two Ru(II) complexes against A549, BEL-7402, HeLa, PC-12, SGC-7901 and SiHa cell lines was investigated by MTT method. Complexes 1 and 2 show moderate cytotoxicity toward BEL-7402 cells with an IC50 value of 53.9 ± 3.4 and 39.3 ± 2.1 μM. The effects of the complexes inducing apoptosis, cellular uptake, reactive oxygen species and mitochondrial membrane potential in BEL-7402 cells have been studied by fluorescence microscopy. The percentages of apoptotic and necrotic cells and cell cycle arrest were studied by flow cytometry. The BSA-binding behaviors were investigated by UV/visible and fluorescent spectra.

  16. Fasting-Mimicking Diet Reduces HO-1 to Promote T Cell-Mediated Tumor Cytotoxicity.

    Science.gov (United States)

    Di Biase, Stefano; Lee, Changhan; Brandhorst, Sebastian; Manes, Brianna; Buono, Roberta; Cheng, Chia-Wei; Cacciottolo, Mafalda; Martin-Montalvo, Alejandro; de Cabo, Rafael; Wei, Min; Morgan, Todd E; Longo, Valter D

    2016-07-11

    Immune-based interventions are promising strategies to achieve long-term cancer-free survival. Fasting was previously shown to differentially sensitize tumors to chemotherapy while protecting normal cells, including hematopoietic stem and immune cells, from its toxic side effects. Here, we show that the combination of chemotherapy and a fasting-mimicking diet (FMD) increases the levels of bone marrow common lymphoid progenitor cells and cytotoxic CD8(+) tumor-infiltrating lymphocytes (TILs), leading to a major delay in breast cancer and melanoma progression. In breast tumors, this effect is partially mediated by the downregulation of the stress-responsive enzyme heme oxygenase-1 (HO-1). These data indicate that FMD cycles combined with chemotherapy can enhance T cell-dependent targeted killing of cancer cells both by stimulating the hematopoietic system and by enhancing CD8(+)-dependent tumor cytotoxicity. PMID:27411588

  17. Lentivirus-Specific Cytotoxic T-Lymphocyte Responses Are Rapidly Lost in Thymectomized Cats Infected with Feline Immunodeficiency Virus

    OpenAIRE

    Hayes, Kathleen A.; Köksoy, Sadi; Phipps, Andrew J.; Buck, Wayne R.; Kociba, Gary J.; Mathes, Lawrence E.

    2005-01-01

    To what extent the thymus is needed to preserve the virus-specific cytotoxic T-lymphocyte (CTL) response of lentivirus-infected adults is unclear. Presented here is the first definitive study using thymectomized (ThX) animals to directly evaluate the contribution of thymic function to lentivirus-specific CTL response and the control of lentivirus infections. ThX and mock-ThX cats were inoculated with feline immunodeficiency virus (FIV) and monitored for their FIV-specific CTL responses. Early...

  18. Cytotoxic effect of soil cyanobacterial extracts to mammal cell lines YAC-1 and WEHI

    Czech Academy of Sciences Publication Activity Database

    Hrouzek, Pavel; Kopecký, Jiří; Salát, Jiří; Maršálek, Blahoslav; Lukešová, Alena

    2005-01-01

    Roč. 5, - (2005), s. 79-90. ISSN 1213-3434 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60660521 Keywords : cytotoxic effect * soil cyanobacterial extracts * mammal cell lines YAC-1 and WEHI Subject RIV: EH - Ecology, Behaviour

  19. Dicoumarol enhances gemcitabine-induced cytotoxicity in high NQO1-expressing cholangiocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Benjaporn; Buranrat; Auemduan; Prawan; Upa; Kukongviriyapan; Sarinya; Kong-petch; Veerapol; Kukongviriyapan

    2010-01-01

    AIM: To investigate whether dicoumarol, a potent inhibitor of NAD(P)H quinone oxidoreductase-1 (NQO1), potentiates gemcitabine to induce cytotoxicity in chol-angiocarcinoma cells (CCA) and the role of reactive oxygen generation in sensitizing the cells. METHODS: Four human cell lines with different NQO1 activity were used; the human CCA cell lines, KKU-100, KKU-OCA17, KKU-M214, and Chang liver cells. NQO1 activity and mRNA expression were determined. The cells were pretreated with dicoumarol at relevant con...

  20. The production of podophyllotoxin and related cytotoxic lignans by plant cell cultures

    NARCIS (Netherlands)

    Uden, Wilhelmus van

    1992-01-01

    Podophyllotoxin is a lignan that occurs in several plant species. Its cytotoxic activity is well-known, but it can not be applied clinically because of severe toxic side effects. Attempts have been undertaken to develop less toxic and more specifically acting antitumour drugs derived from podophyllo

  1. Subamolide B Isolated from Medicinal Plant Cinnamomum subavenium Induces Cytotoxicity in Human Cutaneous Squamous Cell Carcinoma Cells through Mitochondrial and CHOP-Dependent Cell Death Pathways

    OpenAIRE

    Shu-Yi Yang; Hui-Min Wang; Tai-Wen Wu; Yi-Ju Chen; Jeng-Jer Shieh; Ju-Hwa Lin; Tsing-Fen Ho; Ren-Jie Luo; Chung-Yi Chen; Chia-Che Chang

    2013-01-01

    Subamolide B is a butanolide isolated from Cinnamomum subavenium, a medicinal plant traditionally used to treat various ailments including carcinomatous swelling. We herein reported for the first time that subamolide B potently induced cytotoxicity against diverse human skin cancer cell lines while sparing nonmalignant cells. Mechanistic studies on human cutaneous squamous cell carcinoma (SCC) cell line SCC12 highlighted the involvement of apoptosis in subamolide B-induced cytotoxicity, as ev...

  2. Evaluation of cytotoxicity and genotoxicity of insecticide carbaryl to flounder gill cells and its teratogenicity to zebrafish embryos

    Science.gov (United States)

    Pandey, Manish Raj; Guo, Huarong

    2015-04-01

    In this study, we determined the cytotoxicity and genotoxicity of carbamate insecticide carbaryl to flounder gill (FG) cells and its teratogenicity to zebrafish embryos. The cytotoxicity of carbaryl to FG cells was determined with methods including MTT and neutral red uptaking (NRU), lactate dehydrogenase (LDH) releasing and Hoechst 33342 and propidium idodide (PI) double staining. Moderate cytotoxicity in a concentration-dependent manner was observed. The 24 h-IC50 value of 53.48 ± 1.21, 59.13 ± 1.19 and 46.21 ± 1.24 mg L-1 carbaryl was obtained through MTT, NRU and LDH assays, respectively. Double fluorescence staining demonstrated that carbaryl induced the death of FG cells mainly through necrosis. There was no significant genotoxicity found in the FG cells exposed to the highest testing concentration of carbaryl (20 mg L-1, P > 0.05) as was demonstrated by Comet assay. Zebrafish embryos exposed to carbaryl at concentrations ≥10 mg L-1 displayed moderate toxic effects on the survival, spontaneous movement, hatching, heart rates of the embryos and their development, which were evidenced by yolk and pericardial sac edemas, body length reduction and tail flexure in time- and concentration-dependent manners at specific stages. The 24 h-, 48 h- and 96 h-LC50 values of carbaryl to zebrafish embryos were 41.80 ± 1.10, 17.80 ± 1.04 and 14.46 ± 1.05 mg L-1, respectively. These results suggested that carbaryl is moderately toxic to FG cells cultured in vitro and zebrafish embryos, and the FG cells were similar to zebrafish embryos in their sensitivity to carbaryl as 24 h-IC50 and LC50 indicated.

  3. Folate Conjugated Cellulose Nanocrystals Potentiate Irreversible Electroporation-induced Cytotoxicity for the Selective Treatment of Cancer Cells.

    Science.gov (United States)

    Colacino, Katelyn R; Arena, Christopher B; Dong, Shuping; Roman, Maren; Davalos, Rafael V; Lee, Yong W

    2015-12-01

    Cellulose nanocrystals are rod-shaped, crystalline nanoparticles that have shown prom-ise in a number of industrial applications for their unique chemical and physical properties. However, investigations of their abilities in the biomedical field are limited. The goal of this study is to show the potential use of folic acid-conjugated cellulose nanocrystals in the potentiation of irreversible electroporation-induced cell death in folate receptor (FR)-positive cancers. We optimized key pulse parameters including pulse duration, intensity, and incubation time with nanoparticles prior to electroporation. FR-positive cancer cells, KB and MDA-MB-468, were preincubated with cellulose nanocrystals (CNCs) conjugated with the targeting molecule folic acid (FA), 10 and 20 min respectively, prior to application of the optimized pulse electric field (PEF), 600 and 500 V/cm respectively. We have shown cellulose nanocrystals' ability to potentiate a new technique for tumor ablation, irreversible electroporation. Pre-incubation with FA-conjugated CNCs (CNC-FA) has shown a significant increase in cytotoxicity induced by irreversible electroporation in FR-positive cancer cells, KB and MDA-MB-468. Non-targeted CNCs (CNC-COOH) did not potentiate IRE when preincubated at the same parameters as previously stated in these cell types. In addition, CNC-FA did not potentiate irreversible electroporation-induced cytotoxicity in a FR-negative cancer cell type, A549. Without changing irreversible electroporation parameters it is possible to increase the cytotoxic effect on FR-positive cancer cells by exploiting the specific binding of FA to the FR, while not causing further damage to FR-negative tissue. PMID:24750004

  4. In vitro cytotoxicity of superparamagnetic iron oxide nanoparticles on neuronal and glial cells. Evaluation of nanoparticle interference with viability tests.

    Science.gov (United States)

    Costa, Carla; Brandão, Fátima; Bessa, Maria João; Costa, Solange; Valdiglesias, Vanessa; Kiliç, Gözde; Fernández-Bertólez, Natalia; Quaresma, Pedro; Pereira, Eulália; Pásaro, Eduardo; Laffon, Blanca; Teixeira, João Paulo

    2016-03-01

    Superparamagnetic iron oxide nanoparticles (ION) have attracted great interest for use in several biomedical fields. In general, they are considered biocompatible, but little is known of their effects on the human nervous system. The main objective of this work was to evaluate the cytotoxicity of two ION (magnetite), coated with silica and oleic acid, previously determining the possible interference of the ION with the methodological procedures to assure the reliability of the results obtained. Human neuroblastoma SHSY5Y and glioblastoma A172 cells were exposed to different concentrations of ION (5-300 µg ml(-1) ), prepared in complete and serum-free cell culture medium for three exposure times (3, 6 and 24 h). Cytotoxicity was evaluated by means of the MTT, neutral red uptake and alamar blue assays. Characterization of the main physical-chemical properties of the ION tested was also performed. Results demonstrated that both ION could significantly alter absorbance readings. To reduce these interferences, protocols were modified by introducing additional washing steps and cell-free systems. Significant decreases in cell viability were observed for both cell lines in specific conditions by all assays. In general, oleic acid-coated ION were less cytotoxic than silica-coated ION; besides, a serum-protective effect was observed for both ION studied and cell lines. These results contribute to increase the knowledge of the potential harmful effects of ION on the human nervous system. Understanding these effects is essential to establish satisfactory regulatory policies on the safe use of magnetite nanoparticles in biomedical applications. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26212026

  5. Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2Kd, but not H-2Dd. The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

  6. δ-Aminolevulinic acid cytotoxic effects on human hepatocarcinoma cell lines

    Directory of Open Access Journals (Sweden)

    del Batlle Alcira M

    2002-03-01

    Full Text Available Abstract Background Acute Intermittent Porphyria is a genetic disorder of heme metabolism, characterized by increased levels of porphyrin precursors, δ-aminolevulinic acid (ALA and porphobilinogen (PBG. ALA has been reported to generate reactive oxygen species and to cause oxidative damage to proteins, subcellular structures and DNA. It is known that oxidative stress can induce apoptosis. The aim of this work was to study the cytotoxic effect of ALA on two hepatocarcinoma cell lines. Results We have determined the impact of ALA on HEP G2 and HEP 3B hepatocarcinoma cell lines survival as measured by the MTT assay. ALA proved to be cytotoxic in both cell lines however; HEP G2 was more sensitive to ALA than HEP 3B. Addition of hemin or glucose diminished ALA cytotoxicity in HEP G2 cells; instead it was enhanced in HEP 3B cells. Because apoptosis is usually associated with DNA fragmentation, the DNA of ALA treated and untreated cells were analyzed. The characteristic pattern of DNA fragmentation ladders was observed in ALA treated cells. To elucidate the mechanisms of ALA induced apoptosis, we examined its effect on p53 expression. No changes in p53 mRNA levels were observed after exposure of both cell lines to ALA for 24 h. CDK2 and CDK4 protein levels were reduced after ALA treatment at physiological concentrations.

  7. Cytotoxic Effects of Tropodithietic Acid on Mammalian Clonal Cell Lines of Neuronal and Glial Origin

    Directory of Open Access Journals (Sweden)

    Heidi Wichmann

    2015-11-01

    Full Text Available The marine metabolite tropodithietic acid (TDA, produced by several Roseobacter clade bacteria, is known for its broad antimicrobial activity. TDA is of interest not only as a probiotic in aquaculture, but also because it might be of use as an antibacterial agent in non-marine or non-aquatic environments, and thus the potentially cytotoxic influences on eukaryotic cells need to be evaluated. The present study was undertaken to investigate its effects on cells of the mammalian nervous system, i.e., neuronal N2a cells and OLN-93 cells as model systems for nerve cells and glia. The data show that in both cell lines TDA exerted morphological changes and cytotoxic effects at a concentration of 0.3–0.5 µg/mL (1.4–2.4 µM. Furthermore, TDA caused a breakdown of the mitochondrial membrane potential, the activation of extracellular signal-regulated kinases ERK1/2, and the induction of the small heat shock protein HSP32/HO-1, which is considered as a sensor of oxidative stress. The cytotoxic effects were accompanied by an increase in intracellular Ca2+-levels, the disturbance of the microtubule network, and the reorganization of the microfilament system. Hence, mammalian cells are a sensitive target for the action of TDA and react by the activation of a stress response resulting in cell death.

  8. Cytotoxic Effects of Tropodithietic Acid on Mammalian Clonal Cell Lines of Neuronal and Glial Origin.

    Science.gov (United States)

    Wichmann, Heidi; Vocke, Farina; Brinkhoff, Thorsten; Simon, Meinhard; Richter-Landsberg, Christiane

    2015-12-01

    The marine metabolite tropodithietic acid (TDA), produced by several Roseobacter clade bacteria, is known for its broad antimicrobial activity. TDA is of interest not only as a probiotic in aquaculture, but also because it might be of use as an antibacterial agent in non-marine or non-aquatic environments, and thus the potentially cytotoxic influences on eukaryotic cells need to be evaluated. The present study was undertaken to investigate its effects on cells of the mammalian nervous system, i.e., neuronal N2a cells and OLN-93 cells as model systems for nerve cells and glia. The data show that in both cell lines TDA exerted morphological changes and cytotoxic effects at a concentration of 0.3-0.5 µg/mL (1.4-2.4 µM). Furthermore, TDA caused a breakdown of the mitochondrial membrane potential, the activation of extracellular signal-regulated kinases ERK1/2, and the induction of the small heat shock protein HSP32/HO-1, which is considered as a sensor of oxidative stress. The cytotoxic effects were accompanied by an increase in intracellular Ca(2+)-levels, the disturbance of the microtubule network, and the reorganization of the microfilament system. Hence, mammalian cells are a sensitive target for the action of TDA and react by the activation of a stress response resulting in cell death. PMID:26633426

  9. δ-Aminolevulinic acid cytotoxic effects on human hepatocarcinoma cell lines

    International Nuclear Information System (INIS)

    Acute Intermittent Porphyria is a genetic disorder of heme metabolism, characterized by increased levels of porphyrin precursors, δ-aminolevulinic acid (ALA) and porphobilinogen (PBG). ALA has been reported to generate reactive oxygen species and to cause oxidative damage to proteins, subcellular structures and DNA. It is known that oxidative stress can induce apoptosis. The aim of this work was to study the cytotoxic effect of ALA on two hepatocarcinoma cell lines. We have determined the impact of ALA on HEP G2 and HEP 3B hepatocarcinoma cell lines survival as measured by the MTT assay. ALA proved to be cytotoxic in both cell lines however; HEP G2 was more sensitive to ALA than HEP 3B. Addition of hemin or glucose diminished ALA cytotoxicity in HEP G2 cells; instead it was enhanced in HEP 3B cells. Because apoptosis is usually associated with DNA fragmentation, the DNA of ALA treated and untreated cells were analyzed. The characteristic pattern of DNA fragmentation ladders was observed in ALA treated cells. To elucidate the mechanisms of ALA induced apoptosis, we examined its effect on p53 expression. No changes in p53 mRNA levels were observed after exposure of both cell lines to ALA for 24 h. CDK2 and CDK4 protein levels were reduced after ALA treatment at physiological concentrations

  10. Integrin receptors on tumor cells facilitate NK cell-mediated antibody-dependent cytotoxicity.

    Science.gov (United States)

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J; Powers, Gordon D; Sato, Takami; Campbell, Kerry S; Sykulev, Yuri

    2014-08-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high antibody concentration, revealing a dose limiting effect. A similar effect was also observed with primary human NK cells. The effect was erased after IFN-γ treatment of tumor cells resulting in upregulation of ICAM-1. Furthermore, killing of the same tumor cells induced by Herceptin antibody was significantly impaired in the presence of CNTO 95Ala-Ala antibody variant that blocks αV integrins but is incapable of binding to CD16. These data suggest that αV integrins on tumor cells could compensate for the loss of ICAM-1 molecules, thereby facilitating ADCC by NK cells. Thus, NK cells could exercise cytolytic activity against ICAM-1 deficient tumor cells in the absence of proinflammatory cytokines, emphasizing the importance of NK cells in tumor-specific immunity at early stages of cancer. PMID:24810893

  11. Real-time cell-microelectronic sensing of nanoparticle-induced cytotoxic effects

    Energy Technology Data Exchange (ETDEWEB)

    Moe, Birget [Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada T6G 2G3 (Canada); Gabos, Stephan [Alberta Health, 24th floor, Telus Plaza North Tower, 10025 Jasper Avenue, Edmonton, Canada T5J 2N3 (Canada); Li, Xing-Fang, E-mail: xingfang.li@ualberta.ca [Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada T6G 2G3 (Canada)

    2013-07-30

    Graphical abstract: Cell-electronic sensing of 96 tests of nanoparticles. -- Highlights: •Cell-electronic sensing of cytotoxic effects of nanoparticles. •Simultaneous sensing of 96 tests. •Multiplex data of real-time dynamic responses. •Unique temporal IC{sub 50} histograms. •Minimized interference and high throughput analysis. -- Abstract: We report a real-time cell analysis (RTCA) sensing method of 96 electronic microwells for profiling the cytotoxicity of nanoparticles on different cell lines. The method consists of 96 microwells embedded with microelectrodes (96x E-plate) to measure impedance changes of adherent cell lines. When the testing cells change in population, adhesion, and/or morphology, the impedance at the cell–electrode interface changes to provide real-time monitoring of overall cell status. To demonstrate this technique, we used three cell lines as sensing probes: two human lung carcinoma cell lines, A549 and SK-MES-1, and a normal mammalian cell line, CHO-K1. We tested two well-characterized nanoparticles: nano-titanium dioxide (nTiO{sub 2}) and nano-silver (nAg). The three cell lines were separately seeded into 96x E-plates and treated with varying concentrations of nanoparticles (0.078–160 μg mL{sup −1}). This method provides dynamic cell response profiles and temporal IC{sub 50} histograms, showing concentration-, time-, particle-, and cell-dependent cytotoxicity. The 24 h and 48 h IC{sub 50} values of nAg obtained using both the RTCA and the neutral red uptake (NRU) assays were in good agreement, validating the RTCA technique. The RTCA assay does not suffer interference from nTiO{sub 2}, whereas the NRU assay cannot be used due to severe interference from nTiO{sub 2}. A cytostatic response was observed in CHO-K1 cells after 24 h exposure to 40 μg mL{sup −1} nTiO{sub 2}, which was correlated with S-phase cell cycle arrest based on cell cycle analysis using flow cytometry. This suggests that the shapes of the response curves

  12. Isolation of motile Aeromonas spp. from fish and their cytotoxic effect on Vero cell cultures

    Directory of Open Access Journals (Sweden)

    Karabasil Neđeljko

    2002-01-01

    Full Text Available The presence of motile Aeromonas spp. in fish and other sea food on the Belgrade retail market was investigated with the aim of determining the ability of these bacteria to produce and secrete toxins. Nine strains of motile Aeromonas spp. were isolated from seventy-eight food samples. Aer. sobria was identified in three cases, while six of the obtained strains were identified as Aer. hydrophila. Strains of motile Aeromonas spp. from different sources were analyzed for cytotoxicity on Vero cell cultures. A cytotoxic effect was detected for all tested strains, but of different intensity.

  13. Th17 cells promote cytotoxic T cell activation in tumor immunity

    OpenAIRE

    Martin-Orozco, Natalia; Muranski, Pawel; Chung, Yeonseok; Yang, Xuexian O.; Yamazaki, Tomohide; Lu, Sijie; Hwu, Patrick; Restifo, Nicholas P; Overwijk, Willem W.; Dong, Chen

    2009-01-01

    Although T helper 17 (Th17) cells have been found in human tumor tissues, their function in cancer immunity is unclear. Here we show that IL-17-deficient mice were more susceptible to the development of lung melanoma. Conversely, adoptive T cell therapy with tumor-specific Th17 cells prevented tumor development. Importantly, the donor Th17 cells retained their cytokine expression phenotype and exhibited stronger therapeutic efficacy than Th1 cells. Unexpectedly, therapy using Th17 but not Th1...

  14. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay.

    Science.gov (United States)

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc-optimized CD19 antibody (4G7SDIE) and a bi-specific antibody with the specificities CD19 and CD16 (N19-C16) was evaluated in CD107a-degranulation assays and intracellular cytokine staining. CD107a, TNFα, and IFNγ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system) measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits a promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and requires clinical

  15. Cytotoxicity of Algae Extracts on Normal and Malignant Cells

    OpenAIRE

    Jane Liesveld; Karen Rosell; Jeremy Bechelli; Myra Coppage

    2011-01-01

    Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. Primar...

  16. Impaired cytotoxicity associated with defective natural killer cell differentiation in myelodysplastic syndromes.

    Science.gov (United States)

    Hejazi, Maryam; Manser, Angela R; Fröbel, Julia; Kündgen, Andrea; Zhao, Xiaoyi; Schönberg, Kathrin; Germing, Ulrich; Haas, Rainer; Gattermann, Norbert; Uhrberg, Markus

    2015-05-01

    Natural killer cells are well known to mediate anti-leukemic responses in myeloid leukemia but their role in myelodysplastic syndromes is not well understood. Here, in a cohort of newly diagnosed patients (n=75), widespread structural and functional natural killer cell defects were identified. One subgroup of patients (13%) had a selective deficiency of peripheral natural killer cells (count <10/mm(3) blood) with normal frequencies of T and natural killer-like T cells. Natural killer cell-deficient patients were predominantly found in high-risk subgroups and deficiency of these cells was significantly associated with poor prognosis. In the second subgroup, comprising the majority of patients (76%), natural killer cells were present but exhibited poor cytotoxicity. The defect was strongly associated with reduced levels of perforin and granzyme B. Notably, natural killer cell function and arming of cytotoxic granules could be fully reconstituted by in vitro stimulation. Further phenotypic analysis of these patients revealed an immature natural killer cell compartment that was biased towards CD56(bright) cells. The residual CD56(dim) cells exhibited a significant increase of the unlicensed NKG2A(-)KIR(-) subset and a striking reduction in complexity of the repertoire of killer cell immunoglobulin-like receptors. Taken together, these results suggest that the widespread defects in natural killer cell function occurring in patients with myelodysplastic syndromes are mostly due to either unsuccessful or inefficient generation of mature, functionally competent natural killer cells, which might contribute to disease progression through impaired immune surveillance. PMID:25682594

  17. A cytotoxic humanized anti-ganglioside antibody produced in a murine cell line defective of N-glycolylated-glycoconjugates.

    Science.gov (United States)

    Fernández-Marrero, Yuniel; Roque-Navarro, Lourdes; Hernández, Tays; Dorvignit, Denise; Molina-Pérez, Marively; González, Addys; Sosa, Katya; López-Requena, Alejandro; Pérez, Rolando; de Acosta, Cristina Mateo

    2011-12-01

    Gangliosides containing the N-glycolyl (NGc) form of sialic acid are tumor-associated antigens and promising candidates for cancer therapy. We previously generated the murine 14F7 monoclonal antibody (mAb), specific for the N-glycolyl-GM3 ganglioside (NGcGM3), which induced an oncosis-like type of cell death on malignant cell lines expressing this antigen and recognized breast carcinoma by immunoscintigraphy in cancer patients. As humanization is expected to enhance its use for human cancer therapy, herein we describe the design and generation of two humanized versions of the 14F7 mAb by disrupting potential human T cell epitopes on its variable region. No differences in antigen reactivity or cytotoxic properties were detected among the variants tested and with respect to the chimeric counterpart. Humanized 14F7 genes were transfected into the NGcGM3-expressing NS0 cell line. Therefore, in the industrial scaling-up of the transfectoma in serum-free medium, cell viability was lost due to the cytotoxic effect of the secreted antibody. This shortcoming was solved by knocking down the CMP-N-acetylneuraminic acid hydroxylase enzyme, thus impairing the synthesis of NGc-glycoconjugates. Humanized 14F7 mAb is of potential value for the therapy of NGcGM3-expressing tumors. PMID:21802167

  18. Effects of radiation on IL-2 secretion and cytotoxicity of T cells

    International Nuclear Information System (INIS)

    Peripheral blood mononuclear cells (PBMC) from normal persons were irradiated with 1.6 Gy γ-rays in vitro. The method of indirect immunofluorescence was used for analysis of positive percentage of TCR, CD3 and CD25 of T cells. The method of 3H-TdR incorporation and release wa used for determination of IL-2 secretion and T cell cytotoxicity, and immunocytochemistry was used for analysis of expression of TCR and CD3. A decreasing pattern of TCR, CD3 and CD25 expression, IL-2 secretion, and T cell cytotoxicity depending on radiation dose was found. The inhibition of IL-2 secretion and cytotoxicity after irradiation of T cells was associated, in some degree, with decreasing expression and damaging activity of TCR, CD3 and CD25, whereas it was possible that the decreasing expression of TCR and CD3 at the cell surface was related to accumulation of TCR and CD3 in cytoplasm of irradiated T cells

  19. Cytotoxic effect of Erythroxylum suberosum combined with radiotherapy in head and neck cancer cell lines

    International Nuclear Information System (INIS)

    The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as 'cabelo-de-negro'. The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas. (author)

  20. Cytotoxic effect of Erythroxylum suberosum combined with radiotherapy in head and neck cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Taysa B.C.; Torres, Hianne M.; Yamamoto-Silva, Fernanda Paula; Silva, Maria Alves G. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Escola de Odontologia; Elias, Silvia T.; Silveira, Damaris; Magalhaes, Perola O.; Lofrano-Porto, Adriana; Guerra, Eliete N.S., E-mail: elieteneves@unb.br [Universidade de Brasilia (UnB), Brasilia, DF (Brazil). Faculdade de Ciencias da Saude

    2016-01-15

    The mouth and oropharynx cancer is the 6{sup th} most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as 'cabelo-de-negro'. The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas. (author)

  1. Cytotoxic Effect of Erythroxylum suberosum Combined with Radiotherapy in Head and Neck Cancer Cell Lines.

    Science.gov (United States)

    Macedo, Taysa B C; Elias, Silvia T; Torres, Hianne M; Yamamoto-Silva, Fernanda Paula; Silveira, Dâmaris; Magalhães, Pérola O; Lofrano-Porto, Adriana; Guerra, Eliete N S; Silva, Maria Alves G

    2016-01-01

    The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas. PMID:27007356

  2. Cancer Cell Cytotoxicities of 1-(4-Substitutedbenzoyl-4-(4-chlorobenzhydrylpiperazine Derivatives

    Directory of Open Access Journals (Sweden)

    Mine Yarim

    2012-06-01

    Full Text Available A series of novel 1-(4-substitutedbenzoyl-4-(4-chlorobenzhydrylpiperazine derivatives 5ag was designed by a nucleophilic substitution reaction of 1-(4-chlorobenzhydrylpiperazine with various benzoyl chlorides and characterized by elemental analyses, IR and 1H nuclear magnetic resonance spectra. Cytotoxicity of the compounds was demonstrated on cancer cell lines from liver (HUH7, FOCUS, MAHLAVU, HEPG2, HEP3B, breast (MCF7, BT20, T47D, CAMA-1, colon (HCT-116, gastric (KATO-3 and endometrial (MFE-296 cancer cell lines. Time-dependent cytotoxicity analysis of compound 5a indicated the long-term in situ stability of this compound. All compounds showed significant cell growth inhibitory activity on the selected cancer cell lines.

  3. PROTECTIVE EFFECT OF MELATONIN ON NEURAL CELLS AGAINST THE CYTOTOXICITY OF OXYRADICALS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective. To investigate the exact mechanism of melatonin to prohibit the apoptosis of neural cells induced by various kinds of cytotoxic agents.Methods. We used the methods of phase contrast microscopy, MTT assay and hoechst dye staining to check this mechanism in SKNSH and U251 cell lines.Results. Both 2mmol/L H2O2 and 0.5 μ mol/L amyloid β- protein (Aβ) induce these two cell lines die via apoptosis. Either melatonin or glutathione can significantly protect both cell lines. The protective effect of 10 μ mol/L melatonin is as same as that of 60 μ mol/L glutathione.Conclusion. Melatonin can partly inhibit the cytotoxicity of H2O2 and Aβ through its role as a free radical scavenger.

  4. Comparison of the cytotoxicity of cladribine and clofarabine when combined with fludarabine and busulfan in AML cells: enhancement of cytotoxicity with epigenetic modulators

    OpenAIRE

    Valdez, Benigno C.; Li, Yang; Murray, David; Ji, Jie; Liu, Yan; Popat, Uday; Champlin, Richard E.; Andersson, Borje S.

    2015-01-01

    Clofarabine (Clo), fludarabine (Flu) and busulfan (Bu) combinations are efficacious in hematopoietic stem cell transplantation (HSCT) for myeloid leukemia. We now determined if the more affordable drug cladribine (Clad) can provide a viable alternative to Clo, with or without panobinostat (Pano) and 5-aza-2′-deoxycytidine (DAC). Both [Clad+Flu+Bu] and [Clo+Flu+Bu] combinations showed synergistic cytotoxicity in KBM3/Bu2506, HL60 and OCI-AML3 cell lines. Cell exposure to these drug combination...

  5. Cytotoxicity of algae extracts on normal and malignant cells.

    Science.gov (United States)

    Bechelli, Jeremy; Coppage, Myra; Rosell, Karen; Liesveld, Jane

    2011-01-01

    Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. Primary CLL cells showed apoptosis at 24 hours after exposure to Dun, Ast, Spir, and AFA. High AFA concentrations decreased viability of normal marrow cells. Normal CD34+ viability was inhibited by Dun. Dun and AFA inhibited BFU-E, but all extracts inhibited CFU-GM. Cell-cycle analysis of AML cell lines showed G0/G1 arrest in the presence of AFA. These data suggest that algae extracts may inhibit AML cell lines and leukemia blasts, but they may also have potential inhibitory effects on normal hematopoiesis. PMID:23213541

  6. Target cell specific antibody-based photosensitizers for photodynamic therapy

    Science.gov (United States)

    Rosenblum, Lauren T.; Mitsunaga, Makoto; Kakareka, John W.; Morgan, Nicole Y.; Pohida, Thomas J.; Choyke, Peter L.; Kobayashi, Hisataka

    2011-03-01

    In photodynamic therapy (PDT), localized monochromatic light is used to activate targeted photosensitizers (PS) to induce cellular damage through the generation of cytotoxic species such as singlet oxygen. While first-generation PS passively targeted malignancies, a variety of targeting mechanisms have since been studied, including specifically activatable agents. Antibody internalization has previously been employed as a fluorescence activation system and could potentially enable similar activation of PS. TAMRA, Rhodamine-B and Rhodamine-6G were conjugated to trastuzumab (brand name Herceptin), a humanized monoclonal antibody with specificity for the human epidermal growth factor receptor 2 (HER2), to create quenched PS (Tra-TAM, Tra-RhoB, and Tra-Rho6G). Specific PDT with Tra-TAM and Tra-Rho6G, which formed covalently bound H-dimers, was demonstrated in HER2+ cells: Minimal cell death (SDS-PAGE).

  7. Studies on antitumor mechanism of two planar platinum(II) complexes with 8-hydroxyquinoline: synthesis, characterization, cytotoxicity, cell cycle and apoptosis.

    Science.gov (United States)

    Qin, Qi-Pin; Chen, Zhen-Feng; Qin, Jiao-Lan; He, Xiao-Ju; Li, Yu-Lan; Liu, Yan-Cheng; Huang, Ke-Bin; Liang, Hong

    2015-03-01

    [Pt(Q)2] (1) and [Pt(MQ)2] (2) exhibited enhanced cytotoxicity against BEL-7404, Hep-G2, NCI-H460, T-24, A549 tumor cells but low cytotoxicity on normal HL-7702 cells. 1 and 2 could cause the cell cycle arrest in G2 and S phase, respectively. While pifithrin-α, a specific p53 inhibitor, induced cell cycle arrest in G1 phase. Although 1, 2 and pifithrin-α caused serious inhibition on p53, 1 and 2 significantly cause the loss of mitochondrial membrane potential and increase of the reactive oxygen species level, cytochrome c, apaf-1 and caspase-3/9 ratio in BEL-7404 cells. 1 and 2 may trigger the cell apoptosis through a mitochondrial dysfunction pathway whereas pifithrin-α does not. The interactions of 1 and 2 with DNA are most probably via an intercalation. PMID:25575314

  8. In Vitro Cytotoxicity and Phototoxicity Assessment of Acylglutamate Surfactants Using a Human Keratinocyte Cell Line

    OpenAIRE

    Abhay Kyadarkunte; Milind Patole; Varsha Pokharkar

    2014-01-01

    In the current study, human keratinocyte cell line was used as in vitro cell culture model to elucidate the effects of the fatty acid chain length of acylglutamate (amino acid-based surfactant) namely, sodium cocoyl glutamate, sodium lauroyl glutamate, and sodium myristoyl glutamate on their cytotoxicity and the ultraviolet B induced phototoxicity. The endpoint used to assess toxicity was a tetrazolium-based assay whereas, the phototoxic potential of acylglutamate surfactants was predicted u...

  9. Sex steroids do not affect shigatoxin cytotoxicity on human renal tubular or glomerular cells

    OpenAIRE

    Kohan Donald E; Schmid Douglas I; Hughes Alisa K

    2002-01-01

    Abstract Background The greater susceptibility of children to renal injury in post-diarrheal hemolytic-uremic syndrome (HUS) may be related, at least in part, to heightened renal cell sensitivity to the cytotoxic effect of Shiga toxin (Stx), the putative mediator of kidney damage in HUS. We hypothesized that sexual maturation, which coincides with a falling incidence of HUS, may induce a relatively Stx-resistant state in the renal cells. Methods Cultured human glomerular endothelial (HGEN), h...

  10. Cytotoxic Effects of Tropodithietic Acid on Mammalian Clonal Cell Lines of Neuronal and Glial Origin

    OpenAIRE

    Heidi Wichmann; Farina Vocke; Thorsten Brinkhoff; Meinhard Simon; Christiane Richter-Landsberg

    2015-01-01

    The marine metabolite tropodithietic acid (TDA), produced by several Roseobacter clade bacteria, is known for its broad antimicrobial activity. TDA is of interest not only as a probiotic in aquaculture, but also because it might be of use as an antibacterial agent in non-marine or non-aquatic environments, and thus the potentially cytotoxic influences on eukaryotic cells need to be evaluated. The present study was undertaken to investigate its effects on cells of the mammalian nervous system,...

  11. Cytotoxicity of Biologically Synthesized Silver Nanoparticles in MDA-MB-231 Human Breast Cancer Cells

    OpenAIRE

    Sangiliyandi Gurunathan; Jae Woong Han; Vasuki Eppakayala; Muniyandi Jeyaraj; Jin-Hoi Kim

    2013-01-01

    Silver nanoparticles (AgNPs) have been used as an antimicrobial and disinfectant agents. However, there is limited information about antitumor potential. Therefore, this study focused on determining cytotoxic effects of AgNPs on MDA-MB-231 breast cancer cells and its mechanism of cell death. Herein, we developed a green method for synthesis of AgNPs using culture supernatant of Bacillus funiculus, and synthesized AgNPs were characterized by various analytical techniques such as UV-visible spe...

  12. Salinomycin induces selective cytotoxicity to MCF-7 mammosphere cells through targeting the Hedgehog signaling pathway.

    Science.gov (United States)

    Fu, Ying-Zi; Yan, Yuan-Yuan; He, Miao; Xiao, Qing-Huan; Yao, Wei-Fan; Zhao, Lin; Wu, Hui-Zhe; Yu, Zhao-Jin; Zhou, Ming-Yi; Lv, Mu-Tian; Zhang, Shan-Shan; Chen, Jian-Jun; Wei, Min-Jie

    2016-02-01

    Breast cancer stem cells (BCSCs) are believed to be responsible for tumor chemoresistance, recurrence, and metastasis formation. Salinomycin (SAL), a carboxylic polyether ionophore, has been reported to act as a selective breast CSC inhibitor. However, the molecular mechanisms underlying SAL-induced cytotoxicity on BCSCs remain unclear. The Hedgehog (Hh) signaling pathway plays an important role in CSC maintenance and carcinogenesis. Here, we investigated whether SAL induces cytotoxicity on BCSCs through targeting Hh pathway. In the present study, we cultured breast cancer MCF-7 cells in suspension in serum-free medium to obtain breast CSC-enriched MCF-7 mammospheres (MCF-7 MS). MCF-7 MS cells possessed typical BCSC properties, such as CD44+CD24-/low phenotype, high expression of OCT4 (a stem cell marker), increased colony-forming ability, strong migration and invasion capabilities, differentiation potential, and strong tumorigenicity in xenografted mice. SAL exhibited selective cytotoxicity to MCF-7 MS cells relative to MCF-7 cells. The Hh pathway was highly activated in BCSC-enriched MCF-7 MS cells and SAL inhibited Hh signaling activation by downregulating the expression of critical components of the Hh pathway such as PTCH, SMO, Gli1, and Gli2, and subsequently repressing the expression of their essential downstream targets including C-myc, Bcl-2, and Snail (but not cyclin D1). Conversely, Shh-induced Hh signaling activation could largely reverse SAL-mediated inhibitory effects. These findings suggest that SAL-induced selective cytotoxicity against MCF-7 MS cells is associated with the inhibition of Hh signaling activation and the expression of downstream targets and the Hh pathway is an important player and a possible drug target in the pathogenesis of BCSCs. PMID:26718029

  13. Gangliosides inhibit bee venom melittin cytotoxicity but not phospholipase A2-induced degranulation in mast cells

    International Nuclear Information System (INIS)

    Sting accident by honeybee causes severe pain, inflammation and allergic reaction through IgE-mediated anaphylaxis. In addition to this hypersensitivity, an anaphylactoid reaction occurs by toxic effects even in a non-allergic person via cytolysis followed by similar clinical manifestations. Auto-injectable epinephrine might be effective for bee stings, but cannot inhibit mast cell lysis and degranulation by venom toxins. We used connective tissue type canine mast cell line (CM-MC) for finding an effective measure that might inhibit bee venom toxicity. We evaluated degranulation and cytotoxicity by measurement of β-hexosaminidase release and MTT assay. Melittin and crude bee venom induced the degranulation and cytotoxicity, which were strongly inhibited by mono-sialoganglioside (GM1), di-sialoganglioside (GD1a) and tri-sialoganglioside (GT1b). In contrast, honeybee venom-derived phospholipase A2 induced the net degranulation directly without cytotoxicity, which was not inhibited by GM1, GD1a and GT1b. For analysis of distribution of Gαq and Gαi protein by western blotting, lipid rafts were isolated by using discontinuous sucrose gradient centrifuge. Melittin disrupted the localization of Gαq and Gαi at lipid raft, but gangliosides stabilized the rafts. As a result from this cell-based study, bee venom-induced anaphylactoid reaction can be explained with melittin cytotoxicity and phospholipase A2-induced degranulation. Taken together, gangliosides inhibit the effect of melittin such as degranulation, cytotoxicity and lipid raft disruption but not phospholipase A2-induced degranulation in mast cells. Our study shows a potential of gangliosides as a therapeutic tool for anaphylactoid reaction by honeybee sting.

  14. A role of ZnO nanoparticle electrostatic properties in cancer cell cytotoxicity

    Science.gov (United States)

    Wingett, Denise; Louka, Panagiota; Anders, Catherine B; Zhang, Jianhui; Punnoose, Alex

    2016-01-01

    ZnO nanoparticles (NPs) have previously been shown to exhibit selective cytotoxicity against certain types of cancerous cells suggesting their potential use in biomedical applications. In this study, we investigate the effect of surface modification of ZnO NPs on their cytotoxicity to both cancerous and primary T cells. Our results show that polyacrylic acid capping produces negatively charged ZnO NPs that are significantly more toxic compared to uncapped positively charged NPs of identical size and composition. In contrast, the greatest selectivity against cancerous cells relative to normal cells is observed with cationic NPs. In addition, differences in NP cytotoxicity inversely correlate with NP hydrodynamic size, propensity for aggregation, and dissolution profiles. The generation of reactive oxygen species (ROS) was also observed in the toxicity mechanism with anionic NPs generating higher levels of mitochondrial superoxide without appreciably affecting glutathione levels. Additional experiments evaluated the combined effects of charged ZnO NPs and nontoxic cationic or anionic CeO2 NPs. Results show that the CeO2 NPs offer protective effects against cytotoxicity from anionic ZnO NPs via antioxidant properties. Altogether, study data indicate that surface modification of NPs and resulting changes in their surface charge affect the level of intracellular ROS production, which can be ameliorated by the CeO2 ROS scavenger, suggesting that ROS generation is a dominant mechanism of ZnO NP cytotoxicity. These findings demonstrate the importance of surface electrostatic properties for controlling NP toxicity and illustrate an approach for engineering NPs with desired properties for potential use in biological applications. PMID:27486313

  15. In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Paula; M.Kustiawan; Songchan; Puthong; Enos; T.Arung; Chanpen; Chanchao

    2014-01-01

    Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indonesia for cytotoxic activity against five human cancer cell lines(HepG2,SW620,ChaGo-1,KATO-Ⅲand BT474).Methods:All samples were extracted with methanol,and then subpartitioned with n-hexane and ethyl acetate.Each crude extract was screened at 20μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Tn addition,four previously shown bioactive components from propolis(apigenin,cafieic acid phenyl ester,kaempferol and naringenin)and two chemotherapeutic drugs(doxorubicin and 5-fluorouracil)were used to evaluate the sensitivity of the cell lines.Results:Overall,crude extracts from propolis and honey had higher cytotoxic activities than bee pollen,but the activity was dependent upon the extraction solvent,bee species and cell line.Propolis extracts from T.incisa and Tarda apicalis showed the highest and lowest cytotoxic activity,respectively.Only the HepG2 cell line was broadly sensitive to the honey extracts.For pure compounds,doxorubicin was the most cytotoxic,the four propolis compounds the least,but the ChaGo-I cell line was sensitive to kaempferol at 10μg/mL and KATO-Ⅲwas sensitive to kaempferol and apigenin at 10μg/mL,.All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from f,incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines.Further study is required,including the isolation and characterization of the active antiproliferative agent(s).

  16. Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica papaya Leaf Extracts.

    Science.gov (United States)

    Nguyen, Thao T; Parat, Marie-Odile; Hodson, Mark P; Pan, Jenny; Shaw, Paul N; Hewavitharana, Amitha K

    2016-01-01

    In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer. PMID:26712788

  17. Chemical Characterization and in Vitro Cytotoxicity on Squamous Cell Carcinoma Cells of Carica Papaya Leaf Extracts

    Directory of Open Access Journals (Sweden)

    Thao T. Nguyen

    2015-12-01

    Full Text Available In traditional medicine, Carica papaya leaf has been used for a wide range of therapeutic applications including skin diseases and cancer. In this study, we investigated the in vitro cytotoxicity of aqueous and ethanolic extracts of Carica papaya leaves on the human oral squamous cell carcinoma SCC25 cell line in parallel with non-cancerous human keratinocyte HaCaT cells. Two out of four extracts showed a significantly selective effect towards the cancer cells and were found to contain high levels of phenolic and flavonoid compounds. The chromatographic and mass spectrometric profiles of the extracts obtained with Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry were used to tentatively identify the bioactive compounds using comparative analysis. The principal compounds identified were flavonoids or flavonoid glycosides, particularly compounds from the kaempferol and quercetin families, of which several have previously been reported to possess anticancer activities. These results confirm that papaya leaf is a potential source of anticancer compounds and warrant further scientific investigation to validate the traditional use of papaya leaf to treat cancer.

  18. IN VITRO CYTOTOXICITY OF MADHUCA INDICA AGAINST DIFFERENT HUMAN CANCER CELL LINES

    Directory of Open Access Journals (Sweden)

    Satish K. Verma et al.

    2012-05-01

    Full Text Available Cancer is a public health problem all over the world. Large number of plants and their isolated constituents has been shown to potential anticancer activity. Ethanolic whole plant extract of Madhuca indica showed in vitro cytotoxicity against different human cancer cell lines such as lung, neuroblastima, and colon. There was no growth of inhibition recorded against liver cancer cell line. Sulforhodamine B dye (SRB assay was done for in vitro cytotoxicity test assay. The in vitro cytotoxicity was performed against five human cancer cell lines namely of lung (A-549, liver (Hep-2 colon (502713 HT-29 and neuroblastima (IMR-32. The activity was done using 100µg/ml of the extract. Against lung (A-549 cell line plant extract showed 83% growth of inhibition. In case of liver (Hep-2 showed no activity reported, where as in case of colon 502713 cell line plant extract showed maximum activity. In case of HT-29 liver human cancer line and IMR-32 neuroblastima cell line plant extract showed 99% and 98% activity respectively.

  19. Sex steroids do not affect shigatoxin cytotoxicity on human renal tubular or glomerular cells

    Directory of Open Access Journals (Sweden)

    Kohan Donald E

    2002-08-01

    Full Text Available Abstract Background The greater susceptibility of children to renal injury in post-diarrheal hemolytic-uremic syndrome (HUS may be related, at least in part, to heightened renal cell sensitivity to the cytotoxic effect of Shiga toxin (Stx, the putative mediator of kidney damage in HUS. We hypothesized that sexual maturation, which coincides with a falling incidence of HUS, may induce a relatively Stx-resistant state in the renal cells. Methods Cultured human glomerular endothelial (HGEN, human glomerular visceral epithelial (HGEC and human proximal tubule (HPT cells were exposed to Stx-1 after pre-incubation with progesterone, β-estradiol or testosterone followed by determination of cytotoxicity. Results Under basal conditions, Stx-1 potently and dose-dependently killed HPT and HGEC, but had relatively little effect on HGEN. Pre-incubation for 1, 2 or 7 days with physiologic or pharmacologic concentrations of progesterone, β-estradiol or testosterone had no effect on Stx-1 cytotoxicity dose-response on any cell type. In addition, no steroid altered Gb3 expression (Stx receptor by any cell type at any time point. Conclusion These data do not support the notion that hormonal changes associated with puberty induce an Stx-resistant state within kidney cells.

  20. Cytotoxicity and apoptotic effects of nickel oxide nanoparticles in cultured HeLa cells

    International Nuclear Information System (INIS)

    The aim of this study was to observe the cytotoxicity and apoptotic effects of nickel oxide nanoparticles on human cervix epithelioid carcinoma cell line (HeLa). Nickel oxide precursors were synthesized by an nickel sulphate-excess urea reaction in boiling aqueous solution. The synthesized NiO nanoparticles (< 200 nm) were investigated by X-ray diffraction analysis and transmission electron microscopy techniques. For cytotoxicity experiments, HeLa cells were incubated in 50-500 micro g/ml NiO for 2, 6, 12 and 16 hours. The viable cells were counted with a haemacytometer using light microscopy. The cytotoxicity was observed low in 50-200 micro g/ml concentration for 16 h, but high in 400-500 micro g/ml concentration for 2-6 h. HeLa cells cytoplasm membrane was lysed and detached from the well surface in 400 micro g/ml concentration NiO nanoparticles. Double staining and M30 immunostaining were performed to quantify the number of apoptotic cells in culture on the basis of apoptotic cell nuclei scores. The apoptotic effect was observed 20% for 16 h incubation. (authors)

  1. Cytotoxic activity of kenaf (Hibiscus cannabinus L.) seed extract and oil against human cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Yu Hua Wong; Wai Yan Tan; Chin Ping Tan; Kamariah Long; Kar Lin Nyam

    2014-01-01

    Objective: To examine the cytotoxic properties of both the kenaf (Hibiscus cannabinus L.) seed extract and kenaf seed oil on human cervical cancer, human breast cancer, human colon cancer and human lung cancer cell lines.Methods:kenaf seed oil on human cancer cell lines was evaluated by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and sulforhodamine B assays. Cell morphological changes were observed by using an inverted light microscope.Results:The in vitro cytotoxic activity of the kenaf (Hibiscus cannabinus L.) seed extract and cancer cell lines. Morphological alterations in the cell lines after KSE and KSO treatment were observed. KSE and KSO possessed effective cytotoxic activities against all the cell lines been selected.Conclusions:KSE and KSO could be potential sources of natural anti-cancer agents. Further The kenaf seed extract (KSE) exhibited a lower IC50 than kenaf seed oil (KSO) in all of the investigations on using kenaf seeds for anti-proliferative properties are warranted.

  2. Cytotoxicity and apoptotic effects of nickel oxide nanoparticles in cultured HeLa cells

    Directory of Open Access Journals (Sweden)

    Kezban Ada

    2010-04-01

    Full Text Available The aim of this study was to observe the cytotoxicity and apoptotic effects of nickel oxide nanoparticles on humancervix epithelioid carcinoma cell line (HeLa. Nickel oxide precursors were synthesized by an nickel sulphate-excess ureareaction in boiling aqueous solution. The synthesized NiO nanoparticles (<200 nm were investigated by X-ray diffractionanalysis and transmission electron microscopy techniques. For cytotoxicity experiments, HeLa cells were incubated in50-500 μg/mL NiO for 2, 6, 12 and 16 hours. The viable cells were counted with a haemacytometer using light microscopy.The cytotoxicity was observed low in 50-200 μg/mL concentration for 16 h, but high in 400-500 μg/mL concentration for2-6 h. HeLa cells' cytoplasm membrane was lysed and detached from the well surface in 400 μg/mL concentration NiOnanoparticles. Double staining and M30 immunostaining were performed to quantify the number of apoptotic cells in cultureon the basis of apoptotic cell nuclei scores. The apoptotic effect was observed 20% for 16 h incubation.

  3. Preferential accumulation of T helper cells but not cytotoxic T cells characterizes benign subclinical rejection of human liver allografts.

    Science.gov (United States)

    Baumann, Anna K; Schlue, Jerome; Noyan, Fatih; Hardtke-Wolenski, Matthias; Lehner, Frank; Barg-Hock, Hannelore; Klempnauer, Juergen; Manns, Michael P; Taubert, Richard; Jaeckel, Elmar

    2016-07-01

    Subclinical rejection (SCR) is a common event in protocol biopsies after liver transplantation (LT). So far the interpretation of the underlying histological changes and clinical significance is limited. Previous studies were restricted to SCR manifestations within the first weeks after transplantation with limited follow-up. We analyzed clinical data from our prospective protocol biopsy program and found late SCR (at least 3 months after transplantation) to be a common event (41/94 patients). SCR manifested much later than acute cellular rejection (ACR). In the second year after transplantation, the SCR incidence in protocol biopsies reached a plateau of approximately 25% and remained at this level until the latest observed manifestations more than 5 years after transplantation. During a median follow-up of 32 months after SCR, no acute or chronic rejection, relevant graft fibrosis, graft loss, or liver-related death occurred even without specific therapy for SCR. Immunophenotyping of liver biopsies during SCR showed that similar to ACR, the composition of intrahepatic T cells depended on the severity of histological rejection. However, SCR showed a different pattern of infiltrating T cells with a stronger accumulation of CD4(+) cells, an increasing CD4(+) /CD8(+) ratio, and an increasing CD4(+) forkhead box P3 (FOXP3)(+) regulatory T cell (Treg)/CD8(+) ratio, which was not seen in ACR. These intrahepatic T cell patterns were not reflected in the peripheral blood. In conclusion, late SCR after LT has a good clinical prognosis, and it seems safe to leave it untreated. This benign clinical course compared to ACR is associated with intrahepatic T cell infiltration patterns showing less cytotoxic T cells and more CD4(+) FOXP3(+) Tregs. Liver Transplantation 22 943-955 2016 AASLD. PMID:26929119

  4. Uptake and cytotoxicity of chitosan nanoparticles in human liver cells

    International Nuclear Information System (INIS)

    Despite extensive research into the biomedical and pharmaceutical applications of nanoparticles, and the liver being the main detoxifying organ in the human body, there are limited studies which delineate the hepatotoxicity of nanoparticles. This paper reports on the biological interactions between liver cells and chitosan nanoparticles, which have been widely recognised as biocompatible. Using the MTT assay, human liver cells were shown to tolerate up to 4 h of exposure to 0.5% w/v of chitosan nanoparticles (18 ± 1 nm, 7.5 ± 1.0 mV in culture medium). At nanoparticle concentrations above 0.5% w/v, cell membrane integrity was compromised as evidenced by leakage of alanine transaminase into the extracellular milieu, and there was a dose-dependent increase in CYP3A4 enzyme activity. Uptake of chitosan nanoparticles into the cell nucleus was observed by confocal microscopic analysis after 4 h exposure with 1% w/v of chitosan nanoparticles. Electron micrographs further suggest necrotic or autophagic cell death, possibly caused by cell membrane damage and resultant enzyme leakage.

  5. Ethanolic Extract Cytotoxic Effect of Zingiber Afficinale in Breast Cancer (MCF7 Cell Line

    Directory of Open Access Journals (Sweden)

    J Tavakkol Afshari

    2010-07-01

    Full Text Available Introduction & Objective: Biological activities of Zingiber afficieale plants have been reported as possessing anticancer, antibacterial, anti ulcer, antifungal, and insecticidal properties. However, its antitumor effects haven't been studied in cancer cell lines. The aim of this study was to investigate the antitumor effect of zingiber afficieale on breast cancer cell lines. Materials & Methods: This experimental study was conducted in 2010 at Mashhad University of medical Sciences. Breast cancer cell line (MCF7 and normal connective tissue cell line (L929 were cultured in DMEM medium. Ethanolic extract of Zingiber afficinale was prepared and cell lines were treated with different concentration of extract (5000 to 78 µg. Cell viability was measured by MTT assay after 24, 48, and 72 hours. The collected data were statistically analyzed by SPSS software. Results: The effects of Zingiber afficinale on cell viability were observed after 48 hours on cell lines. Ginger doses in 2500 µg concentration inhibited 50% of cell growth (IC50 in cell lines after 48 hours. Conclusion: Our study revealed that fresh ginger extract has cytotoxic effects on tumor cells, but it doesn’t have any cytotoxic effect on normal cells. It seems that ginger could be considered as a promising chemotherapeutic agent in cancer treatment.

  6. Cytotoxic Activity of Piper cubeba Extract in Breast Cancer Cell Lines

    Science.gov (United States)

    Graidist, Potchanapond; Martla, Mananya; Sukpondma, Yaowapa

    2015-01-01

    This study aimed to evaluate the cytotoxicity of a crude extract of Piper cubeba against normal and breast cancer cell lines. To prepare the extract, P. cubeba seeds were ground, soaked in methanol and dichloromethane and isolated by column chromatography. Fractions were tested for cytotoxicity effects on normal fibroblast (L929), normal breast (MCF-12A) and breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231). The most effective fraction was selected for DNA fragmentation assay to detect apoptotic activity. The results showed that the methanolic crude extract had a higher cytotoxic activity against MDA-MB-468 and MCF-7 than a dichloromethane crude extract. Then, the methanolic crude extract was separated into six fractions, designated A to F. Fraction C was highly active against breast cancer cell lines with an IC50 value less than 4 μg/mL. Therefore, Fraction C was further separated into seven fractions, CA to CG. The 1H-NMR profile showed that Fraction CE was long chain hydrocarbons. Moreover, Fraction CE demonstrated the highest activity against MCF-7 cells with an IC50 value of 2.69 ± 0.09 μg/mL and lower cytotoxicity against normal fibroblast L929 cells with an IC50 value of 4.17 ± 0.77 μg/mL. Finally, DNA fragmentation with a ladder pattern characteristic of apoptosis was observed in MCF-7, MDA-MB-468, MDA-MB-231 and L929 cells, but not in MCF-12A cells. PMID:25867951

  7. Cytotoxicity of Marchantia convoluta leaf extracts to human liver and lung cancer cells

    Directory of Open Access Journals (Sweden)

    Xiao J.B.

    2006-01-01

    Full Text Available The cytotoxicity of three extracts (petroleum ether, ethyl acetate and n-butanol from a plant used in folk medicine, Marchantia convoluta, to human non-small cell lung carcinoma (H1299 and liver carcinoma (HepG2 cell lines was tested. After 72-h incubation of lung and liver cancer cell cultures with varying concentrations of extracts (15 to 200 µg/mL, cytotoxicity was determined by the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay and reported in terms of cell viability. The extracts that showed a significant cytotoxicity were subjected to gas chromatography-mass spectrometry analysis to identify the components. The ethyl acetate, but not the petroleum ether or n-butanol extract, had a significant cytotoxicity against lung and liver carcinoma cells with IC50 values of 100 and 30 µg/mL, respectively. A high concentration of ethyl acetate extract (100 µg/mL rapidly reduced the number of H1299 cells. At lower concentrations of ethyl acetate extract (15, 30, and 40 µg/mL, the numbers of HepG2 cells started to decrease markedly. Gas chromatography-mass spectrometry analysis of the ethyl acetate extract revealed the presence of several compounds such as phytol (23.42%, 1,2,4-tripropylbenzene (13.09%, 9-cedranone (12.75%, ledene oxide (7.22%, caryophyllene (1.82%, and caryophyllene oxide (1.15%. HPLC analysis result showed that there were no flavonoids in ethyl acetate extract, but flavonoids are abundant in n-butanol extract. Further studies are needed regarding the identification, toxicity, and mechanism of action of active compounds.

  8. Identification of HLA-A*2402-restricted HCMV immediate early-1 (IE-1 epitopes as targets for CD8+ HCMV-specific cytotoxic T lymphocytes

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    Lee Sang-Guk

    2009-08-01

    Full Text Available Abstract Background To identify novel HLA-A*2402-restricted human cytomegalovirus (HCMV immediate early-1 (IE-1 epitopes for adoptive immunotherapy, we explored 120 overlapping 15-amino acid spanning IE-1. Methods These peptides were screened by measuring the frequency of polyclonal CD8+ T cells producing intracellular interferon-γ (IFN-γ using flow cytometry and the epitopes were validated with a HCMV-infected target Cr release cytotoxicity assay. Results Initial screening was performed with 12 mini-pools of 10 consecutive peptides made from 120 overlapping peptides15-amino acids in length that spanned IE-1. When peripheral blood mononuclear cells (PBMCs from HLA-A*2402 HCMV-seropositive donors were sensitized with each of the 12 mini-pools, mini-pools 1 and 2 induced the highest frequency of CD8+ cytotoxic T lymphocytes (CTLs producing IFN-γ. When PBMCs were stimulated with each of the twenty peptides belonging to mini-pools 1 and 2, peptides IE-11–15MESSAKRKMDPDNPD and IE-15–19AKRKMDPDNPDEGPS induced the greatest quantities of IFN-γ production and cytotoxicity of HLA-matched HCMV-infected fibroblasts. To determine the exact HLA-A*2402-restricted epitopes within the two IE-1 proteins, we synthesized a total of twenty-one overlapping 9- or 10 amino acid peptides spanning IE-11–15 and IE-15–19. Peptide IE-13–12SSAKRKMDPD induced the greatest quantities of IFN-γ production and target cell killing by CD8+ CTLs. Conclusion HCMV IE-13–12SSAKRKMDPD is a HLA-A*2402-restricted HCMV IE-1 epitope that can serve as a common target for CD8+ HCMV-specific CTLs.

  9. Cytotoxic Activities against Breast Cancer Cells of Local Justicia gendarussa Crude Extracts

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    Zahidah Ayob

    2014-01-01

    Full Text Available Justicia gendarussa methanolic leaf extracts from five different locations in the Southern region of Peninsular Malaysia and two flavonoids, kaempferol and naringenin, were tested for cytotoxic activity. Kaempferol and naringenin were two flavonoids detected in leaf extracts using gas chromatography-flame ionization detection (GC-FID. The results indicated that highest concentrations of kaempferol and naringenin were detected in leaves extracted from Mersing with 1591.80 mg/kg and 444.35 mg/kg, respectively. Positive correlations were observed between kaempferol and naringenin concentrations in all leaf extracts analysed with the Pearson method. The effects of kaempferol and naringenin from leaf extracts were examined on breast cancer cell lines (MDA-MB-231 and MDA-MB-468 using MTT assay. Leaf extract from Mersing showed high cytotoxicity against MDA-MB-468 and MDA-MB-231 with IC50 values of 23 μg/mL and 40 μg/mL, respectively, compared to other leaf extracts. Kaempferol possessed high cytotoxicity against MDA-MB-468 and MDA-MB-231 with IC50 values of 23 μg/mL and 34 μg/mL, respectively. These findings suggest that the presence of kaempferol in Mersing leaf extract contributed to high cytotoxicity of both MDA-MB-231 and MDA-MB-468 cancer cell lines.

  10. Cytotoxic and genotoxic effects of abamectin, chlorfenapyr, and imidacloprid on CHOK1 cells.

    Science.gov (United States)

    Al-Sarar, Ali S; Abobakr, Yasser; Bayoumi, Alaa E; Hussein, Hamdy I

    2015-11-01

    The cytotoxicity and genotoxicity of abamectin, chlorfenapyr, and imidacloprid have been evaluated on the Chinese hamster ovary (CHOK1) cells. Neutral red incorporation (NRI), total cellular protein content (TCP), and methyl tetrazolium (MTT) assays were followed to estimate the mid-point cytotoxicity values, NRI50, TCP50, and MTT50, respectively. The effects of the sublethal concentration (NRI25) on glutathione S-transferase (GST), glutathione reductase (GRD), glutathione peroxidase (GPX), and total glutathione content have been evaluated in the presence and absence of reduced glutathione (GSH), vitamin C, and vitamin E. The genotoxicity was evaluated using chromosomal aberrations (CA), micronucleus (MN) formation, and DNA fragmentation techniques in the presence and absence of the metabolic activation system, S9 mix. Abamectin was the most cytotoxic pesticide followed by chlorfenapyr, while imidacloprid was the least cytotoxic one. The glutathione redox cycle components were altered by the tested pesticides in the absence and presence of the tested antioxidants. The results of genotoxicity indicate that abamectin, chlorfenapyr, and imidacloprid have potential genotoxic effects on CHOK1 cells under the experimental conditions. PMID:26122579

  11. Particle Size Affects Concentration-Dependent Cytotoxicity of Chitosan Nanoparticles towards Mouse Hematopoietic Stem Cells

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    Siti Sarah Omar Zaki

    2015-01-01

    Full Text Available Chitosan nanoparticles (CSNPs have been extensively applied in medical and pharmaceutical fields as promising drug delivery systems. Despite that, the safety of CSNPs remains inadequate and needs further investigation, particularly on hematopoietic stem cells (HSCs. CSNPs were prepared by ionic gelation method and later were characterized for their physical characteristics (particle size and zeta potential. Cytotoxicity of CSNPs was assessed by MTT assay. Particle size was highly influenced by chitosan concentration and molecular weight (medium and high molecular weight (MMW and HMW. Higher chitosan concentration and molecular weight produced larger nanoparticles. Zeta potential of CSNPs was not significantly affected by chitosan concentrations and molecular weights used in the present study. MMW had a better stability than HMW CSNPs as their particle size and zeta potential were not significantly altered after autoclaving. Cytotoxicity of CSNPs was influenced by zeta potential and particle size. On the other hand, chitosan concentration and molecular weight indirectly influenced cytotoxicity by affecting particle size and zeta potential of CSNPs. In conclusion, cytotoxicity of CSNPs was mainly attributed to their physical characteristics and this opens a strategy to ensure the safety of CSNPs applications in stem cell technology.

  12. Cytotoxic Activities against Breast Cancer Cells of Local Justicia gendarussa Crude Extracts

    Science.gov (United States)

    Abd Samad, Azman; Jamil, Shajarahtunnur

    2014-01-01

    Justicia gendarussa methanolic leaf extracts from five different locations in the Southern region of Peninsular Malaysia and two flavonoids, kaempferol and naringenin, were tested for cytotoxic activity. Kaempferol and naringenin were two flavonoids detected in leaf extracts using gas chromatography-flame ionization detection (GC-FID). The results indicated that highest concentrations of kaempferol and naringenin were detected in leaves extracted from Mersing with 1591.80 mg/kg and 444.35 mg/kg, respectively. Positive correlations were observed between kaempferol and naringenin concentrations in all leaf extracts analysed with the Pearson method. The effects of kaempferol and naringenin from leaf extracts were examined on breast cancer cell lines (MDA-MB-231 and MDA-MB-468) using MTT assay. Leaf extract from Mersing showed high cytotoxicity against MDA-MB-468 and MDA-MB-231 with IC50 values of 23 μg/mL and 40 μg/mL, respectively, compared to other leaf extracts. Kaempferol possessed high cytotoxicity against MDA-MB-468 and MDA-MB-231 with IC50 values of 23 μg/mL and 34 μg/mL, respectively. These findings suggest that the presence of kaempferol in Mersing leaf extract contributed to high cytotoxicity of both MDA-MB-231 and MDA-MB-468 cancer cell lines. PMID:25574182

  13. Development of IgG Mediated Antibody Dependent Cell-mediated Cytotoxicity (ADCC) in the Serum and Genital Mucosa of HIV Seroconverters

    OpenAIRE

    Aziz, Mariam; Mahmood, Fareeha; Mata, Mariana; Durkin, Helen G.; Liu, Chenglong; Greenblatt, Ruth M.; Nowicki, Marek; Elizabeth T Golub; Anastos, Kathryn; French, Audrey L.; Baum, Linda L.

    2015-01-01

    Background We measured antibody-dependent cell mediated cytotoxicity (ADCC) activity in serum and genital fluids of heterosexually exposed women during HIV seroconversion. Methods Plasma and cervico-vaginal lavage (CVL) fluid from 11 seroconverters (SC) were analyzed biannually from one year pre- to 6 year post-seroconversion using a 51Cr-release assay to measure HIV-1 gp120 specific ADCC. Results No SC had significant HIV specific CVL ADCC activity before seroconversion or until 1.5 yr after...

  14. γδ T cell-mediated antibody-dependent cellular cytotoxicity with CD19 antibodies assessed by an impedance-based label-free real-time cytotoxicity assay

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    Ursula Jördis Eva Seidel

    2014-12-01

    Full Text Available γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation (SCT strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC with monoclonal antibodies (mAbs. These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL. To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc optimized CD19 antibody (4G7SDIE and a bispecific antibody with the specificities CD19 and CD16 (N19-C16 was evaluated in CD107a degranulation assays and intracellular cytokine staining (ICS. CD107a, TNF-α and IFN-γ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits an promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and

  15. Biocompatibility of various ferrite nanoparticles evaluated by in vitro cytotoxicity assays using HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Tomitaka, Asahi [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan)], E-mail: d07gd158@ynu.ac.jp; Hirukawa, Atsuo; Yamada, Tsutomu [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan); Morishita, Shin [Department of Mechanical Engineering and Materials Science, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan); Takemura, Yasushi [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan)

    2009-05-15

    Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Fe{sub 3}O{sub 4} (20-30 nm), ZnFe{sub 2}O{sub 4} (15-30 nm) and NiFe{sub 2}O{sub 4} (20-30 nm) nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. The Fe{sub 3}O{sub 4} sample was found to be biocompatible on HeLa cells. While ZnFe{sub 2}O{sub 4} and NiFe{sub 2}O{sub 4} were non-toxic at low concentrations, HeLa cells exhibited cytotoxic effects when exposed to concentrations of 100 {mu}g/ml nanoparticles.

  16. Inactivation of chromatin remodeling factors sensitizes cells to selective cytotoxic stress

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    Freeman MD

    2014-11-01

    Full Text Available Miles D Freeman, Tryphon Mazu, Jana S Miles, Selina Darling-Reed, Hernan Flores-Rozas College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, USA Abstract: The SWI/SNF chromatin-remodeling complex plays an essential role in several cellular processes including cell proliferation, differentiation, and DNA repair. Loss of normal function of the SWI/SNF complex because of mutations in its subunits correlates with tumorigenesis in humans. For many of these cancers, cytotoxic chemotherapy is the primary, and sometimes the only, therapeutic alternative. Among the antineoplastic agents, anthracyclines are a common treatment option. Although effective, resistance to these agents usually develops and serious dose-related toxicity, namely, chronic cardiotoxicity, limits its use. Previous work from our laboratory showed that a deletion of the SWI/SNF factor SNF2 resulted in hypersensitivity to doxorubicin. We further investigated the contribution of other chromatin remodeling complex components in the response to cytotoxic chemotherapy. Our results indicate that, of the eight SWI/SNF strains tested, snf2, taf14, and swi3 were the most sensitive and displayed distinct sensitivity to different cytotoxic agents, while snf5 displayed resistance. Our experimental results indicate that the SWI/SNF complex plays a critical role in protecting cells from exposure to cytotoxic chemotherapy and other cytotoxic agents. Our findings may prove useful in the development of a strategy aimed at targeting these genes to provide an alternative by hypersensitizing cancer cells to chemotherapeutic agents. Keywords: chromatin remodeling, cancer, DNA damage/repair, heat-shock response, oxidative stress

  17. Relationship of CD86 surface marker expression and cytotoxicity on dendritic cells exposed to chemical allergen

    International Nuclear Information System (INIS)

    Human peripheral blood-derived dendritic cells (DC) respond to a variety of chemical allergens by up-regulating expression of the co-stimulatory molecule CD86. It has been postulated that this measure might provide the basis for an in vitro alternative approach for the identification of skin sensitizing chemicals. We recently reported that DC, exposed in culture to the highest non-cytotoxic concentrations of various chemical allergens, displayed marginal up-regulation of membrane CD86 expression; the interpretation being that such changes were insufficiently sensitive for the purposes of hazard identification. For the work presented here, immature DC were derived from human monocytes and treated with the chemical allergens 2,4-dinitrobenzenesulfonic acid (DNBS), nickel sulfate (NiSO4), p-phenylenediamine (PPD), Bandrowski's base (BB), hydroquinone (HQ) and propyl gallate (PG) for 48 h at concentrations which induced both no to slight to moderate cytotoxicity. For comparison, DC were treated with the irritants sodium dodecyl sulfate (SDS), benzoic acid (BA), and benzalkonium chloride (BZC) at concentrations resulting in comparable levels of cytotoxicity. CD86 expression, as measured by flow cytometry, was consistently up-regulated (ranging from 162 to 386% control) on DC treated with concentrations of chemical allergens that induced approximately 10-15% cytotoxicity. The irritants BA and BZC did not induce up-regulation of CD86 expression when tested at concentrations that induced similar levels of cytotoxicity. SDS, however, up-regulated CD86 expression to 125-138% of control in 2/4 preparations when tested at concentrations which induced similar toxicity. Our results confirm that chemical allergens up-regulate CD86 expression on blood-derived DC and illustrate further that up-regulation of CD86 surface marker expression is more robust when DC are treated with concentrations of chemical allergen that induce slight to moderate cytotoxicity

  18. Deoxysphingolipids, novel biomarkers for type 2 diabetes, are cytotoxic for insulin-producing cells.

    Science.gov (United States)

    Zuellig, Richard A; Hornemann, Thorsten; Othman, Alaa; Hehl, Adrian B; Bode, Heiko; Güntert, Tanja; Ogunshola, Omolara O; Saponara, Enrica; Grabliauskaite, Kamile; Jang, Jae-Hwi; Ungethuem, Udo; Wei, Yu; von Eckardstein, Arnold; Graf, Rolf; Sonda, Sabrina

    2014-04-01

    Irreversible failure of pancreatic β-cells is the main culprit in the pathophysiology of diabetes, a disease that is now a global epidemic. Recently, elevated plasma levels of deoxysphingolipids, including 1-deoxysphinganine, have been identified as a novel biomarker for the disease. In this study, we analyzed whether deoxysphingolipids directly compromise the functionality of insulin-producing Ins-1 cells and primary islets. Treatment with 1-deoxysphinganine induced dose-dependent cytotoxicity with senescent, necrotic, and apoptotic characteristics and compromised glucose-stimulated insulin secretion. In addition, 1-deoxysphinganine altered cytoskeleton dynamics, resulting in intracellular accumulation of filamentous actin and activation of the Rho family GTPase Rac1. Moreover, 1-deoxysphinganine selectively upregulated ceramide synthase 5 expression and was converted to 1-deoxy-dihydroceramides without altering normal ceramide levels. Inhibition of intracellular 1-deoxysphinganine trafficking and ceramide synthesis improved the viability of the cells, indicating that the intracellular metabolites of 1-deoxysphinganine contribute to its cytotoxicity. Analyses of signaling pathways identified Jun N-terminal kinase and p38 mitogen-activated protein kinase as antagonistic effectors of cellular senescence. The results revealed that 1-deoxysphinganine is a cytotoxic lipid for insulin-producing cells, suggesting that the increased levels of this sphingolipid observed in diabetic patients may contribute to the reduced functionality of pancreatic β-cells. Thus, targeting deoxysphingolipid synthesis may complement the currently available therapies for diabetes. PMID:24379346

  19. Assessment of cytotoxicity and oxidative stress induced by titanium oxide nanoparticles on Chinook salmon cells.

    Science.gov (United States)

    Srikanth, Koigoora; Pereira, Eduarda; Duarte, Armando C; Ahmad, Iqbal; Rao, Janapala Venkateswara

    2015-10-01

    Titanium oxide nanoparticles (TiO2 NPs) have received wide attention in diverse application, but the potential impact of these nanomaterials on the environment, aquatic life and especially on fish cell lines is lacking. The present study aimed to investigate the cytotoxicity and oxidative stress induced by TiO2 NPs on Chinook salmon cells derived from Oncorhynchus tshawytscha embryos (CHSE-214). The The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] and neutral red (NR) assays in CHSE-214 cells exposed to TiO2 NPs revealed concentration-dependent cytotoxic effect in the range of 10 to 60 μg/ml for 24 h. CHSE-214 cells exposed to TiO2 NPs (10-60 μg/ml) exhibited significant decline in superoxide dismutase (SOD), catalase (CAT) glutathione (GSH) content and increased lipid peroxidation (LPO) in a concentration-dependent manner. TiO2 NPs induced cytotoxicity and oxidative stress in CHSE-214 cells which serve as a base line studies for future studies. PMID:26013742

  20. Cytotoxicity and Apoptotic Effects of Polyphenols from Sugar Beet Molasses on Colon Carcinoma Cells in Vitro

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    Mingshun Chen

    2016-06-01

    Full Text Available Three polyphenols were isolated and purified from sugar beet molasses by ultrasonic-aid extraction and various chromatographic techniques, and their structures were elucidated by spectral analysis. Cytotoxicity and the molecular mechanism were measured by methyl thiazolyl tetrazolium (MTT assay, flow cytometry, caspase-3 activity assay and Western blot assay. The results showed that gallic acid, cyanidin-3-O-glucoside chloride and epicatechin have cytotoxicity to the human colon, hepatocellular and breast cancer cells. Cyanidin-3-O-glucoside chloride showed its cytotoxicity against various tumor cell lines, particularly against colon cancer Caco-2 cells with half maximal inhibitory concentration (IC50 value of 23.21 ± 0.14 μg/mL in vitro. Cyanidin-3-O-glucoside chloride may be a potential candidate for the treatment of colon cancer. In the mechanism study, cyanidin-3-O-glucoside chloride increased the ratio of cell cycle at G0/G1 phase and reduced cyclin D1 expression on Caco-2 cells. Cyanidin-3-O-glucoside chloride decreased mutant p21 expression, and increased the ratio of Bax/Bcl-2 and the activation of caspase-3 to induce apoptosis.

  1. Cytotoxicity and Apoptotic Effects of Polyphenols from Sugar Beet Molasses on Colon Carcinoma Cells in Vitro.

    Science.gov (United States)

    Chen, Mingshun; Zhao, Zhengang; Yu, Shujuan

    2016-01-01

    Three polyphenols were isolated and purified from sugar beet molasses by ultrasonic-aid extraction and various chromatographic techniques, and their structures were elucidated by spectral analysis. Cytotoxicity and the molecular mechanism were measured by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry, caspase-3 activity assay and Western blot assay. The results showed that gallic acid, cyanidin-3-O-glucoside chloride and epicatechin have cytotoxicity to the human colon, hepatocellular and breast cancer cells. Cyanidin-3-O-glucoside chloride showed its cytotoxicity against various tumor cell lines, particularly against colon cancer Caco-2 cells with half maximal inhibitory concentration (IC50) value of 23.21 ± 0.14 μg/mL in vitro. Cyanidin-3-O-glucoside chloride may be a potential candidate for the treatment of colon cancer. In the mechanism study, cyanidin-3-O-glucoside chloride increased the ratio of cell cycle at G₀/G₁ phase and reduced cyclin D1 expression on Caco-2 cells. Cyanidin-3-O-glucoside chloride decreased mutant p21 expression, and increased the ratio of Bax/Bcl-2 and the activation of caspase-3 to induce apoptosis. PMID:27347927

  2. Reduced cadmium-induced cytotoxicity in cultured liver cells following 5-azacytidine pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Waalkes, M.P.; Wilson, M.J.; Poirier, L.A.

    1985-11-01

    Recent work indicated that administration of the pyrimidine analog 5-azacytidine (AZA), either to cells in culture or to rats, results in an enhancement of expression of the metallothionein (MT) gene. Since MT is thought to play a central role in the detoxification of cadmium, the present study was designed to assess the effect of AZA pretreatment on cadmium cytotoxicity. Cultured rat liver cells in log phase of growth were first exposed to AZA (8 microM). Forty-eight hours later, cadmium was added. A modest increase in MT amounts over control was detected after AZA treatment alone. Cadmium alone resulted in a 10-fold increase in MT concentrations. The combination of AZA pretreatment followed by cadmium exposure caused a 23-fold increase in MT concentrations over control. Treatment with the DNA synthesis inhibitor hydroxyurea (HU) eliminated the enhancing effect of AZA pretreatment on cadmium induction of MT, indicating that cell division is required. AZA-pretreated cells were also harvested and incubated in suspension with cadmium for 0 to 90 min. AZA-pretreated cells showed marked reductions in cadmium-induced cytotoxicity as reflected by reduced intracellular potassium loss, glutamic-oxaloacetic transaminase loss, and lipid peroxidation following cadmium exposure. Results suggest that AZA pretreatment induces tolerance to cadmium cytotoxicity which appears to be due to an increased capacity to synthesize MT rather than high quantities of preexisting MT at the time of cadmium exposure.

  3. Reduced cadmium-induced cytotoxicity in cultured liver cells following 5-azacytidine pretreatment

    International Nuclear Information System (INIS)

    Recent work indicated that administration of the pyrimidine analog 5-azacytidine (AZA), either to cells in culture or to rats, results in an enhancement of expression of the metallothionein (MT) gene. Since MT is thought to play a central role in the detoxification of cadmium, the present study was designed to assess the effect of AZA pretreatment on cadmium cytotoxicity. Cultured rat liver cells in log phase of growth were first exposed to AZA (8 microM). Forty-eight hours later, cadmium was added. A modest increase in MT amounts over control was detected after AZA treatment alone. Cadmium alone resulted in a 10-fold increase in MT concentrations. The combination of AZA pretreatment followed by cadmium exposure caused a 23-fold increase in MT concentrations over control. Treatment with the DNA synthesis inhibitor hydroxyurea (HU) eliminated the enhancing effect of AZA pretreatment on cadmium induction of MT, indicating that cell division is required. AZA-pretreated cells were also harvested and incubated in suspension with cadmium for 0 to 90 min. AZA-pretreated cells showed marked reductions in cadmium-induced cytotoxicity as reflected by reduced intracellular potassium loss, glutamic-oxaloacetic transaminase loss, and lipid peroxidation following cadmium exposure. Results suggest that AZA pretreatment induces tolerance to cadmium cytotoxicity which appears to be due to an increased capacity to synthesize MT rather than high quantities of preexisting MT at the time of cadmium exposure

  4. Synthesis and Cytotoxic Evaluation of a Series of 2-Amino-Naphthoquinones against Human Cancer Cells

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    Thiago A. P. de Moraes

    2014-08-01

    Full Text Available The cytotoxicity of a series of aminonaphthoquinones resulting from the reaction of suitable aminoacids with 1,4-naphthoquinone was assayed against SF-295 (glioblastoma, MDAMB-435 (breast, HCT-8 (colon, HCT-116 (colon, HL-60 (leukemia, OVCAR-8 (ovarian, NCI-H358M (bronchoalveolar lung carcinoma and PC3-M (prostate cancer cells and also against PBMC (peripheral blood mononuclear cells. The results demonstrated that all the synthetic aminonaphthoquinones had relevant cytotoxic activity against all human cancer lines used in this experiment. Five of the compounds showed high cytotoxicity and selectivity against all cancer cell lines tested (IC50 = 0.49 to 3.89 µg·mL−1. The title compounds were less toxic to PBMC, since IC50 was 1.5 to eighteen times higher (IC50 = 5.51 to 17.61 µg·mL−1 than values shown by tumour cell lines. The mechanism of cell growth inhibition and structure–activity relationships remains as a target for future investigations.

  5. Cytotoxicity of Metal Ions Released from Nitinol Alloys on Endothelial Cells

    Science.gov (United States)

    Haider, W.; Munroe, N.; Tek, V.; Gill, P. K. S.; Tang, Y.; McGoron, A. J.

    2011-07-01

    Most implantable medical devices are expected to function in the body over an extended period of time. Therefore, immersion tests under simulated conditions can be useful for assessing the amount of metal ions released in situ. In this investigation, dissolved ions from as-received binary and ternary Nitinol alloys in cell culture media were periodically measured under static and dynamic conditions. Endothelial cells were grown in aliquots of culture media obtained and the effect of dissolved ions on cell proliferation and viability of endothelial cells (HUVEC) was studied by cytotoxicity assays. The concentration of metal ions in the media was measured by inductively coupled plasma mass spectrometry.

  6. The Aryl Hydrocarbon Receptor: Differential Contribution to T Helper 17 and T Cytotoxic 17 Cell Development

    OpenAIRE

    Hayes, Mark D.; Ovcinnikovs, Vitalijs; Smith, Andrew G.; Kimber, Ian; Dearman, Rebecca J

    2014-01-01

    The aryl hydrocarbon receptor (AhR) has been shown to be required for optimal Thelper (Th) 17 cell activation. Th17 cells provide immunity against extracellular pathogens and are implicated in autoimmune diseases. Herein, the role of the AhR in cytokine production by Th17, and by the analogous population of T cytotoxic (Tc)17 cells, has been examined. Lymph node Tc (CD8+) and Th (CD4+) cells were isolated by negative selection from naive AhR+/− and AhR−/− mice and polarised to Tc1/Th1 or Tc17...

  7. The Aryl Hydrocarbon Receptor: Differential Contribution to T Helper 17 and T Cytotoxic 17 Cell Development

    OpenAIRE

    Mark D Hayes; Vitalijs Ovcinnikovs; Smith, Andrew G.; Ian Kimber; Dearman, Rebecca J.

    2014-01-01

    The aryl hydrocarbon receptor (AhR) has been shown to be required for optimal Thelper (Th) 17 cell activation. Th17 cells provide immunity against extracellular pathogens and are implicated in autoimmune diseases. Herein, the role of the AhR in cytokine production by Th17, and by the analogous population of T cytotoxic (Tc)17 cells, has been examined. Lymph node Tc (CD8(+)) and Th (CD4(+)) cells were isolated by negative selection from naive AhR(+/-) and AhR(-/-) mice and polarised to Tc1/Th1...

  8. The Influences of Cell Type and ZnO Nanoparticle Size on Immune Cell Cytotoxicity and Cytokine Induction

    Directory of Open Access Journals (Sweden)

    Thurber Aaron

    2009-01-01

    Full Text Available Abstract Nanotechnology represents a new and enabling platform that promises to provide a range of innovative technologies for biological applications. ZnO nanoparticles of controlled size were synthesized, and their cytotoxicity toward different human immune cells evaluated. A differential cytotoxic response between human immune cell subsets was observed, with lymphocytes being the most resistant and monocytes being the most susceptible to ZnO nanoparticle-induced toxicity. Significant differences were also observed between previously activated memory lymphocytes and naive lymphocytes, indicating a relationship between cell-cycle potential and nanoparticle susceptibility. Mechanisms of toxicity involve the generation of reactive oxygen species, with monocytes displaying the highest levels, and the degree of cytotoxicity dependent on the extent of nanoparticle interactions with cellular membranes. An inverse relationship between nanoparticle size and cytotoxicity, as well as nanoparticle size and reactive oxygen species production was observed. In addition, ZnO nanoparticles induce the production of the proinflammatory cytokines, IFN-γ, TNF-α, and IL-12, at concentrations below those causing appreciable cell death. Collectively, these results underscore the need for careful evaluation of ZnO nanoparticle effects across a spectrum of relevant cell types when considering their use for potential new nanotechnology-based biological applications.

  9. Cytotoxic T-cells from T-cell receptor transgenic NOD8.3 mice destroy beta-cells via the perforin and Fas pathways.

    Science.gov (United States)

    Dudek, Nadine L; Thomas, Helen E; Mariana, Lina; Sutherland, Robyn M; Allison, Janette; Estella, Eugene; Angstetra, Eveline; Trapani, Joseph A; Santamaria, Pere; Lew, Andrew M; Kay, Thomas W H

    2006-09-01

    Cytotoxic T-cells are the major mediators of beta-cell destruction in type 1 diabetes, but the molecular mechanisms are not definitively established. We have examined the contribution of perforin and Fas ligand to beta-cell destruction using islet-specific CD8(+) T-cells from T-cell receptor transgenic NOD8.3 mice. NOD8.3 T-cells killed Fas-deficient islets in vitro and in vivo. Perforin-deficient NOD8.3 T-cells were able to destroy wild-type but not Fas-deficient islets in vitro. These results imply that NOD8.3 T-cells use both pathways and that Fas is required for beta-cell killing only when perforin is missing. Consistent with this theory, transgenic NOD8.3 mice with beta-cells that do not respond to Fas ligation were not protected from diabetes. We next investigated the mechanism of protection provided by overexpression of suppressor of cytokine signaling-1 (SOCS-1) in beta-cells of NOD8.3 mice. SOCS-1 islets remained intact when grafted into NOD8.3 mice and were less efficiently killed in vitro. However, addition of exogenous peptide rendered SOCS-1 islets susceptible to 8.3 T-cell-mediated lysis. Therefore, NOD8.3 T-cells use both perforin and Fas pathways to kill beta-cells and the surprising blockade of NOD8.3 T-cell-mediated beta-cell death by SOCS-1 overexpression may be due in part to reduced target cell recognition. PMID:16936188

  10. A Comparison between the Cytotoxicity Induced by Gossypol in Two Testicular Cell Lines

    Directory of Open Access Journals (Sweden)

    Neda MahdinezhadGorji

    2014-12-01

    Full Text Available Background: Gossypol is a yellow toxic pigment from the cottonseed that can cause acute or chronic toxicity in humans and animals by affecting the testicular tissues. Nowadays cottonseed is used as food supplement for ruminants specially the sheep. In this study, two different stem cell lines of testicular tissue including GC1-spg (mouse testis and SFTF-PI43 (sheep testis cells were used to evaluation of gossypol cytotoxicity. Methods: The GC-1spg and the SFTF_PI43 cells were cultured in RPMI-1640 supplemented with fetal bovine serum (10% and antibiotic (penicillin 105/ml, streptomycin100μg/ml, and then 5×104 cells/well were seeded in 24 well plates. Cultured cells were exposed to four different concentrations of gossypol (1.25, 2.5, 5 and 10μM. After 24 h incubation, cells viability test was performed using Trypan Blue dye exclusion and MTT assay. The Thiobarbituric Acid Reacting Substances (TBARS and Ferric Reducing Activity Potential (FRAP assays was performed on media. Result: In high concentrations (over than 2.5μM, Gossypol showed cytotoxic effects on cells. The IC50 for gossypol (using MTT assays on SFTF-PI43 and GC-1spg cell lines was 2.2 μM and 3.2 μM, respectively. While the results for FRAP assay did not show any significant differences between the test and control groups, significantly higher lipid peroxidation was observed in SFTF-PI43 cells that were treated with higher doses of gossypol (10μM. Conclusion: In this research, we found that gossypol has cytotoxic effects on both examined testicular cell lines and increased lipid peroxidation, which is a probable mechanism of its toxicity on cell lines.

  11. Procyanidin B2 cytotoxicity to MCF-7 human breast adenocarcinoma cells

    Directory of Open Access Journals (Sweden)

    Monalisa M Avelar

    2012-01-01

    Full Text Available Procyanidins have attracted some attention due to their demonstrated chemopreventive action, a relatively new and promising strategy to prevent cancer. Breast cancer is one of the leading causes of death in women worldwide and its treatment needs improvements. The aim of this work was to verify the procyanidin dimmer B2 cytotoxic effect to MCF-7 human breast cancer cells. MCF-7 cells were cultured in RPMI medium, containing 20% fetal bovine serum and antibiotics in a CO 2 chamber. The cells were treated with different concentrations of B2 and its cytotoxic potential was assessed by the sulforhodamine B assay, morphologically through haematoxylin-eosin staining and by DNA fragmentation analysis. The significance of differences between experimental conditions was determined using the ANOVA test, followed by the Tukey test when P<0.05. Cell proliferation decreased in a concentration and time-dependent manner upon procyanidin dimmer B2 treatment, being 19.20 μM the IC 50 . Procyanidin dimmer B2 treatment displayed concentration and time-dependent decline in MCF-7 cells compared to control and also induced morphological alterations compatible with cell-death induction. Cell condensation and cell diameter decreased (3.5 folds compared to control cells, after 48 h cell-exposure to 50 μM procyanidin dimmer B2, but the DNA ladder formation was not observed. In conclusion, our results demonstrated that procyanidin dimmer B2 exhibits cytotoxic activity to MCF-7 cells and it could be a potential antineoplastic agent. Further studies are necessary to clarify the procyanidin dimmer B2 mechanism of action. The evaluation of biological efficacy of individual components is an important step towards drug discovery and development.

  12. Induction of cytotoxic CD8+CD56+ T cells from human thymocytes by interleukin-15

    DEFF Research Database (Denmark)

    Thulesen, S; Nissen, Mogens Holst; Ødum, N; Röpke, C

    2001-01-01

    CD8(+) CD56(+) cells isolated from human peripheral blood lymphocytes have been shown recently to represent a population of cytotoxic active T cells. However, it is not known if these cells are intrathymically or extrathymically developed or how these cells are influenced by growth factors. In the...... present study, we investigated the effects of interleukin-2 (IL-2) and IL-15 on human thymocytes with respect to development of CD8(+) CD56(+) T cells. Freshly isolated thymocytes contain few CD8(+) CD56(+) cells, but the number of these cells increases significantly when thymocytes are grown in the...... presence of IL-15 or IL-2. However, IL-15 induced a significantly higher fraction of CD8(+) CD56(+) cells compared with IL-2. Thus, although IL-2 and IL-15 are known to have a number of redundant functions, we here demonstrate that IL-15 is superior to IL-2 in inducing CD8(+) CD56(+) T cells from cultures...

  13. Parvovirus B19 Genotype Specific Amino Acid Substitution in NS1 Reduces the Protein's Cytotoxicity in Culture

    Directory of Open Access Journals (Sweden)

    Violetta Kivovich, Leona Gilbert, Matti Vuento, Stanley J. Naides

    2010-01-01

    Full Text Available A clinical association between idiopathic liver disease and parvovirus B19 infection has been observed. Fulminant liver failure, not associated with other liver-tropic viruses, has been attributed to B19 in numerous reports, suggesting a possible role for B19 components in the extensive hepatocyte cytotoxicity observed in this condition. A recent report by Abe and colleagues (Int J Med Sci. 2007;4:105-9 demonstrated a link between persistent parvovirus B19 genotype I and III infection and fulminant liver failure. The genetic analysis of isolates obtained from these patients demonstrated a conservation of key amino acids in the nonstructural protein 1 (NS1 of the disease-associated genotypes. In this report we examine a conserved residue identified by Abe and colleagues and show that substitution of isoleucine 181 for methionine, as occurs in B19 genotype II, results in the reduction of B19 NS1-induced cytotoxicity of liver cells. Our results support the hypothesis that in the setting of persistent B19 infection, direct B19 NS1-induced cytotoxicity may play a role in idiopathic fulminant liver failure.

  14. Enhancement of radiation cytotoxicity in breast-cancer cells by localized attachment of gold nanoparticles.

    Science.gov (United States)

    Kong, Tao; Zeng, Jie; Wang, Xiaoping; Yang, Xiaoyan; Yang, Jing; McQuarrie, Steve; McEwan, Alexander; Roa, Wilson; Chen, Jie; Xing, James Z

    2008-09-01

    Gold nanoparticles (GNPs) and modified GNPs having two kinds of functional molecules, cysteamine (AET) and thioglucose (Glu), are synthesized. Cell uptake and radiation cytotoxicity enhancement in a breast-cancer cell line (MCF-7) versus a nonmalignant breast-cell line (MCF-10A) are studied. Transmission electron microscopy (TEM) results show that cancer cells take up functional Glu-GNPs significantly more than naked GNPs. The TEM results also indicate that AET-capped GNPs are mostly bound to the MCF-7 cell membrane, while Glu-GNPs enter the cells and are distributed in the cytoplasm. After MCF-7 cell uptake of Glu-GNPs, or binding of AET-GNPs, the in vitro cytotoxicity effects are observed at 24, 48, and 72 hours. The results show that these functional GNPs have little or no toxicity to these cells. To validate the enhanced killing effect on cancer cells, various forms of radiation are applied such as 200 kVp X-rays and gamma-rays, to the cells, both with and without functional GNPs. By comparison with irradiation alone, the results show that GNPs significantly enhance cancer killing. PMID:18712753

  15. Synergistic cytotoxicity of gemcitabine, clofarabine and edelfosine in lymphoma cell lines.

    Science.gov (United States)

    Valdez, B C; Zander, A R; Song, G; Murray, D; Nieto, Y; Li, Y; Champlin, R E; Andersson, B S

    2014-01-01

    Treatments for lymphomas include gemcitabine (Gem) and clofarabine (Clo) which inhibit DNA synthesis. To improve their cytotoxicity, we studied their synergism with the alkyl phospholipid edelfosine (Ed). Exposure of the J45.01 and SUP-T1 (T-cell) and the OCI-LY10 (B-cell) lymphoma cell lines to IC10-IC20 levels of the drugs resulted in strong synergistic cytotoxicity for the 3-drug combination based on various assays of cell proliferation and apoptosis. Cell death correlated with increased phosphorylation of histone 2AX and KAP1, decreased mitochondrial transmembrane potential, increased production of reactive oxygen species and release of pro-apoptotic factors. Caspase 8-negative I9.2 cells were considerably more resistant to [Gem+Clo+Ed] than caspase 8-positive cells. In all three cell lines [Gem+Clo+Ed] decreased the level of phosphorylation of the pro-survival protein AKT and activated the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) stress signaling pathway, which in J45.01 cells resulted in the phosphorylation and heterodimerization of the transcription factors ATF2 and c-Jun. The observed rational mechanism-based efficacy of [Gem+Clo+Ed] based on the synergistic convergence of several pro-death and anti-apoptotic signaling pathways in three very different cell backgrounds provides a powerful foundation for undertaking clinical trials of this drug combination for the treatment of lymphomas. PMID:24413065

  16. Synergistic cytotoxicity of gemcitabine, clofarabine and edelfosine in lymphoma cell lines

    International Nuclear Information System (INIS)

    Treatments for lymphomas include gemcitabine (Gem) and clofarabine (Clo) which inhibit DNA synthesis. To improve their cytotoxicity, we studied their synergism with the alkyl phospholipid edelfosine (Ed). Exposure of the J45.01 and SUP-T1 (T-cell) and the OCI-LY10 (B-cell) lymphoma cell lines to IC10–IC20 levels of the drugs resulted in strong synergistic cytotoxicity for the 3-drug combination based on various assays of cell proliferation and apoptosis. Cell death correlated with increased phosphorylation of histone 2AX and KAP1, decreased mitochondrial transmembrane potential, increased production of reactive oxygen species and release of pro-apoptotic factors. Caspase 8-negative I9.2 cells were considerably more resistant to [Gem+Clo+Ed] than caspase 8-positive cells. In all three cell lines [Gem+Clo+Ed] decreased the level of phosphorylation of the pro-survival protein AKT and activated the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) stress signaling pathway, which in J45.01 cells resulted in the phosphorylation and heterodimerization of the transcription factors ATF2 and c-Jun. The observed rational mechanism-based efficacy of [Gem+Clo+Ed] based on the synergistic convergence of several pro-death and anti-apoptotic signaling pathways in three very different cell backgrounds provides a powerful foundation for undertaking clinical trials of this drug combination for the treatment of lymphomas

  17. Idarubicin induces mTOR-dependent cytotoxic autophagy in leukemic cells

    International Nuclear Information System (INIS)

    We investigated if the antileukemic drug idarubicin induces autophagy, a process of programmed cellular self-digestion, in leukemic cell lines and primary leukemic cells. Transmission electron microscopy and acridine orange staining demonstrated the presence of autophagic vesicles and intracellular acidification, respectively, in idarubicin-treated REH leukemic cell line. Idarubicin increased punctuation/aggregation of microtubule-associated light chain 3B (LC3B), enhanced the conversion of LC3B-I to autophagosome-associated LC3B-II in the presence of proteolysis inhibitors, and promoted the degradation of the selective autophagic target p62, thus indicating the increase in autophagic flux. Idarubicin inhibited the phosphorylation of the main autophagy repressor mammalian target of rapamycin (mTOR) and its downstream target p70S6 kinase. The treatment with the mTOR activator leucine prevented idarubicin-mediated autophagy induction. Idarubicin-induced mTOR repression was associated with the activation of the mTOR inhibitor AMP-activated protein kinase and down-regulation of the mTOR activator Akt. The suppression of autophagy by pharmacological inhibitors or LC3B and beclin-1 genetic knockdown rescued REH cells from idarubicin-mediated oxidative stress, mitochondrial depolarization, caspase activation and apoptotic DNA fragmentation. Idarubicin also caused mTOR inhibition and cytotoxic autophagy in K562 leukemic cell line and leukocytes from chronic myeloid leukemia patients, but not healthy controls. By demonstrating mTOR-dependent cytotoxic autophagy in idarubicin-treated leukemic cells, our results warrant caution when considering combining idarubicin with autophagy inhibitors in leukemia therapy. - Highlights: • Idarubicin induces autophagy in leukemic cell lines and primary leukemic cells. • Idarubicin induces autophagy by inhibiting mTOR in leukemic cells. • mTOR suppression by idarubicin is associated with AMPK activation and Akt blockade.

  18. Idarubicin induces mTOR-dependent cytotoxic autophagy in leukemic cells

    Energy Technology Data Exchange (ETDEWEB)

    Ristic, Biljana [Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade (Serbia); Bosnjak, Mihajlo [Institute of Histology and Embryology, School of Medicine, University of Belgrade, Belgrade (Serbia); Arsikin, Katarina [Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade (Serbia); Mircic, Aleksandar; Suzin-Zivkovic, Violeta [Institute of Histology and Embryology, School of Medicine, University of Belgrade, Belgrade (Serbia); Bogdanovic, Andrija [Clinic for Hematology, Clinical Centre of Serbia, School of Medicine, University of Belgrade, Belgrade (Serbia); Perovic, Vladimir [Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade (Serbia); Martinovic, Tamara; Kravic-Stevovic, Tamara; Bumbasirevic, Vladimir [Institute of Histology and Embryology, School of Medicine, University of Belgrade, Belgrade (Serbia); Trajkovic, Vladimir, E-mail: vtrajkovic@med.bg.ac.rs [Institute of Microbiology and Immunology, School of Medicine, University of Belgrade, Dr. Subotica 1, 11000 Belgrade (Serbia); Harhaji-Trajkovic, Ljubica, E-mail: buajk@yahoo.com [Institute for Biological Research, University of Belgrade, Belgrade, Despot Stefan Blvd. 142, 11000 Belgrade (Serbia)

    2014-08-01

    We investigated if the antileukemic drug idarubicin induces autophagy, a process of programmed cellular self-digestion, in leukemic cell lines and primary leukemic cells. Transmission electron microscopy and acridine orange staining demonstrated the presence of autophagic vesicles and intracellular acidification, respectively, in idarubicin-treated REH leukemic cell line. Idarubicin increased punctuation/aggregation of microtubule-associated light chain 3B (LC3B), enhanced the conversion of LC3B-I to autophagosome-associated LC3B-II in the presence of proteolysis inhibitors, and promoted the degradation of the selective autophagic target p62, thus indicating the increase in autophagic flux. Idarubicin inhibited the phosphorylation of the main autophagy repressor mammalian target of rapamycin (mTOR) and its downstream target p70S6 kinase. The treatment with the mTOR activator leucine prevented idarubicin-mediated autophagy induction. Idarubicin-induced mTOR repression was associated with the activation of the mTOR inhibitor AMP-activated protein kinase and down-regulation of the mTOR activator Akt. The suppression of autophagy by pharmacological inhibitors or LC3B and beclin-1 genetic knockdown rescued REH cells from idarubicin-mediated oxidative stress, mitochondrial depolarization, caspase activation and apoptotic DNA fragmentation. Idarubicin also caused mTOR inhibition and cytotoxic autophagy in K562 leukemic cell line and leukocytes from chronic myeloid leukemia patients, but not healthy controls. By demonstrating mTOR-dependent cytotoxic autophagy in idarubicin-treated leukemic cells, our results warrant caution when considering combining idarubicin with autophagy inhibitors in leukemia therapy. - Highlights: • Idarubicin induces autophagy in leukemic cell lines and primary leukemic cells. • Idarubicin induces autophagy by inhibiting mTOR in leukemic cells. • mTOR suppression by idarubicin is associated with AMPK activation and Akt blockade.

  19. CYTOTOXICITY AND MODE OF CELL DEATH INDUCED BY TRIPHENYLTIN (IV) COMPOUNDS IN VITRO

    OpenAIRE

    Normah Awang; Zalila Abdul Aziz; Nurul Farahana Kamaludin; Kok Meng Chan

    2014-01-01

    A series of newly synthesized organotin (IV) with N-alkyl-N-phenyldithiocarbamate ligands namely triphenyltin (IV) ethylphenyldithiocarbamate (compound 1) and triphenyltin (IV) butylphenyldithiocarbamate (compound 2) were assessed for their cytotoxic effect against HT-29 human colon adenocarcinoma cells and human CCD-18Co normal colon cells. The cytotoxicity of these organotins in both cells was assessed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazholium bromide (MTT) assay upon 24 ...

  20. Cytotoxic and apoptotic effects of six herbal plants against the human hepatocarcinoma (HepG2) cell line

    OpenAIRE

    Nonpunya Apiyada; Sripanidkulchai Bungorn; Barusrux Sahapat; Weerapreeyakul Natthida; Machana Sasipawan; Thitimetharoch Thaweesak

    2011-01-01

    Abstract Background Six plants from Thailand were evaluated for their cytotoxicity and apoptosis induction in human hepatocarcinoma (HepG2) as compared to normal African green monkey kidney epithelial cell lines. Methods Ethanol-water crude extracts of the six plants were tested with neutral red assay for their cytotoxicity after 24 hours of exposure to the cells. Apoptotic induction was tested in the HepG2 cells with diamidino-2-phenylindole staining. DNA fragmentation, indicative of apoptos...

  1. Hexavalent chromium is cytotoxic and genotoxic to hawksbill sea turtle cells

    International Nuclear Information System (INIS)

    Sea turtles are a charismatic and ancient ocean species and can serve as key indicators for ocean ecosystems, including coral reefs and sea grass beds as well as coastal beaches. Genotoxicity studies in the species are absent, limiting our understanding of the impact of environmental toxicants on sea turtles. Hexavalent chromium (Cr(VI)) is a ubiquitous environmental problem worldwide, and recent studies show it is a global marine pollutant of concern. Thus, we evaluated the cytotoxicity and genotoxicity of soluble and particulate Cr(VI) in hawksbill sea turtle cells. Particulate Cr(VI) was both cytotoxic and genotoxic to sea turtle cells. Concentrations of 0.1, 0.5, 1, and 5 μg/cm2 lead chromate induced 108, 79, 54, and 7% relative survival, respectively. Additionally, concentrations of 0, 0.1, 0.5, 1, and 5 μg/cm2 lead chromate induced damage in 4, 10, 15, 26, and 36% of cells and caused 4, 11, 17, 30, and 56 chromosome aberrations in 100 metaphases, respectively. For soluble Cr, concentrations of 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate induced 84, 69, 46, 25, and 3% relative survival, respectively. Sodium chromate induced 3, 9, 9, 14, 21, and 29% of metaphases with damage, and caused 3, 10, 10, 16, 26, and 39 damaged chromosomes in 100 metaphases at concentrations of 0, 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate, respectively. These data suggest that Cr(VI) may be a concern for hawksbill sea turtles and sea turtles in general. - Highlights: • Particulate Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Soluble Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Cr(VI) may be a risk factor for hawksbill sea turtle health

  2. Hexavalent chromium is cytotoxic and genotoxic to hawksbill sea turtle cells

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Sandra S., E-mail: sandra.wise@maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Xie, Hong, E-mail: hongxie@usm.maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Fukuda, Tomokazu, E-mail: tomofukuda009@gmail.com [Graduate School of Agricultural Sciences, Tohoku University, Laboratory of Animal Breeding and Genetics, Second Research Building, Rm 112, 1-1 Amamiyamachi, Aoba-ku, Sendai 981-8555 (Japan); Douglas Thompson, W., E-mail: dougt@usm.maine.edu [Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); and others

    2014-09-01

    Sea turtles are a charismatic and ancient ocean species and can serve as key indicators for ocean ecosystems, including coral reefs and sea grass beds as well as coastal beaches. Genotoxicity studies in the species are absent, limiting our understanding of the impact of environmental toxicants on sea turtles. Hexavalent chromium (Cr(VI)) is a ubiquitous environmental problem worldwide, and recent studies show it is a global marine pollutant of concern. Thus, we evaluated the cytotoxicity and genotoxicity of soluble and particulate Cr(VI) in hawksbill sea turtle cells. Particulate Cr(VI) was both cytotoxic and genotoxic to sea turtle cells. Concentrations of 0.1, 0.5, 1, and 5 μg/cm{sup 2} lead chromate induced 108, 79, 54, and 7% relative survival, respectively. Additionally, concentrations of 0, 0.1, 0.5, 1, and 5 μg/cm{sup 2} lead chromate induced damage in 4, 10, 15, 26, and 36% of cells and caused 4, 11, 17, 30, and 56 chromosome aberrations in 100 metaphases, respectively. For soluble Cr, concentrations of 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate induced 84, 69, 46, 25, and 3% relative survival, respectively. Sodium chromate induced 3, 9, 9, 14, 21, and 29% of metaphases with damage, and caused 3, 10, 10, 16, 26, and 39 damaged chromosomes in 100 metaphases at concentrations of 0, 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate, respectively. These data suggest that Cr(VI) may be a concern for hawksbill sea turtles and sea turtles in general. - Highlights: • Particulate Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Soluble Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Cr(VI) may be a risk factor for hawksbill sea turtle health.

  3. Molecular basis of arsenite (As+3-induced acute cytotoxicity in human cervical epithelial carcinoma cells

    Directory of Open Access Journals (Sweden)

    Muhammad Nauman Arshad

    2015-04-01

    Full Text Available Background: Rapid industrialization is discharging toxic heavy metals into the environment, disturbing human health in many ways and causing various neurologic, cardiovascular, and dermatologic abnormalities and certain types of cancer. The presence of arsenic in drinking water from different urban and rural areas of the major cities of Pakistan, for example, Lahore, Faisalabad, and Kasur, was found to be beyond the permissible limit of 10 parts per billion set by the World Health Organization. Therefore the present study was initiated to examine the effects of arsenite (As+3 on DNA biosynthesis and cell death. Methods: After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and flow cytometry. Results: We show that As+3 ions have a dose- and time-dependent cytotoxic effect through the activation of the caspase-dependent apoptotic pathway. In contrast to previous research, the present study was designed to explore the early cytotoxic effects produced in human cells during exposure to heavy dosage of As+3 (7.5 µg/ml. Even treatment for 1 h significantly increased the mRNA levels of p21 and p27 and caspases 3, 7, and 9. It was interesting that there was no change in the expression levels of p53, which plays an important role in G2/M phase cell cycle arrest. Conclusion: Our results indicate that sudden exposure of cells to arsenite (As+3 resulted in cytotoxicity and mitochondrial-mediated apoptosis resulting from up-regulation of caspases.

  4. Cytotoxicity and oxidative stress induced by different metallic nanoparticles on human kidney cells

    Directory of Open Access Journals (Sweden)

    Ohayon-Courtès Céline

    2011-03-01

    Full Text Available Abstract Background Some manufactured nanoparticles are metal-based and have a wide variety of applications in electronic, engineering and medicine. Until now, many studies have described the potential toxicity of NPs on pulmonary target, while little attention has been paid to kidney which is considered to be a secondary target organ. The objective of this study, on human renal culture cells, was to assess the toxicity profile of metallic nanoparticles (TiO2, ZnO and CdS usable in industrial production. Comparative studies were conducted, to identify whether particle properties impact cytotoxicity by altering the intracellular oxidative status. Results Nanoparticles were first characterized by size, surface charge, dispersion and solubility. Cytotoxicity of NPs was then evaluated in IP15 (glomerular mesangial and HK-2 (epithelial proximal cell lines. ZnO and CdS NPs significantly increased the cell mortality, in a dose-dependent manner. Cytotoxic effects were correlated with the physicochemical properties of NPs tested and the cell type used. Analysis of reactive oxygen species and intracellular levels of reduced and oxidized glutathione revealed that particles induced stress according to their composition, size and solubility. Protein involved in oxidative stress such as NF-κb was activated with ZnO and CdS nanoparticles. Such effects were not observed with TiO2 nanoparticles. Conclusion On glomerular and tubular human renal cells, ZnO and CdS nanoparticles exerted cytotoxic effects that were correlated with metal composition, particle scale and metal solubility. ROS production and oxidative stress induction clearly indicated their nephrotoxic potential.

  5. Radiosensitizing effect of 2,4-dinitroimidazole-1-ethanol and its cytotoxicity in HeLa S3 cells

    International Nuclear Information System (INIS)

    Using cultured HeLa S3 cells, the radiosensitizing and cytotoxic effects of newly synthesized derivatives of dinitroimidazole were investigated and compared with those of misonidazole. 2,4-dinitroimidazole-1-ethanol radiosensitized hypoxic cells selectively. At 5 mM misonidazole, the enhancement ratio was 1.95; with 0.5 mM 2,4-dinitroimidazole-1-ethanol, almost the same enhancement could be obtained. This indicates that the radiosensitizing effect of the latter agent was about 10 times greater than that of misonidazole. However, its cytotoxicity was twice that of misonidazole under hypoxic conditions and there was no apparent differential cytotoxicity to hypoxic and aerobic cells. (orig.)

  6. A novel metabolite from aspergillus ochraceus JGI 25 showing cytotoxicity to hela cells

    Directory of Open Access Journals (Sweden)

    Varalakshmi K Nadumane

    2013-01-01

    Full Text Available This study aims at the isolation of filamentous fungi, extraction of metabolites, and evaluation of the cytotoxic properties on HeLa cells and normal human lymphocytes. We isolated fungi from the soil by serial dilution method. One of the isolates was chosen and identified as Aspergillus ochraceus Wilhelm (Trichocomaceae by standard techniques. The metabolites were extracted using methanol. Different concentrations of the extract were evaluated for their potential anticancer activity on HeLa cells by 3-(4,5-dimethylthiazol-2yl-2,5-diphenyl tetrazolium bromide assay and the safety of the extract was checked on normal human lymphocytes. The extract was purified by chromatographic techniques like thin-layer chromatography and high-performance liquid chromatography, and subjected to mass spectrometric analysis. The extract showed significant cytotoxic potential on HeLa cells at low concentrations with a half maximal inhibitory concentration value of <50 ΅g/ml. The extract gave 10 fractions by thin layer chromatography, and fraction B had higher toxicity than the rest. This fraction gave a single peak by high-performance liquid chromatography and had a mass-to-charge ratio of 905.65, which did not match any of the earlier known fungal metabolites or metabolites from other strains of A. ochraceus. The metabolite from A. ochraceus is alkaloid in nature, cytotoxic to HeLa cells, and appears to be a novel with anticancer potentials, which could be explored further for characterization of the active component.

  7. Interactive cytotoxicity of etoposide and radiation on cultured Chinese hamster V-79 cells

    International Nuclear Information System (INIS)

    Etoposide is a semisynthetic derivative of podophyllotoxin and is an active antitumor agent. The interactive cytotoxic effect of Etoposide and radiation was investigated using cultured Chinese hamster V-79 cells. The surviving fraction of the cells was reduced by only 20%, when the cells were exposed to 5μg/ml of Etoposide for 30 min. Etoposide at this concentration reduced the width of the shoulder of the radiation survival curve. The change became more significant with increase in the concentration of Etoposide. The Dqs (quasithreshold doses) of the radiation survival curves were 5.39, 3.28, 2.13 and 0.54Gy, although the Dos (37% dose slopes) of the radiation survival curves were 2.55, 2.49, 2.39 and 2.18 Gy, when combination treatment with radiaiton and 0, 5, 10 and 20 μg/ml of Etoposide, respectively, was carried out. The cytotoxic effect became increased when fractional treatments with Etoposide and radiation were performed. The results obtained suggest that the mechanism of the interactive cytotoxic effect of this combination treatment involves a reciprocal action of Etoposide and sublethal damage by the radiation to the cells. (author)

  8. Interactive cytotoxicity of etoposide and radiation on cultured Chinese hamster V-79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Tsutomu; Shimada, Yuji; Kamata, Rikisaburo (Nihon Univ., Tokyo (Japan). School of Medicine)

    1989-10-01

    Etoposide is a semisynthetic derivative of podophyllotoxin and is an active antitumor agent. The interactive cytotoxic effect of Etoposide and radiation was investigated using cultured Chinese hamster V-79 cells. The surviving fraction of the cells was reduced by only 20%, when the cells were exposed to 5mug/ml of Etoposide for 30 min. Etoposide at this concentration reduced the width of the shoulder of the radiation survival curve. The change became more significant with increase in the concentration of Etoposide. The Dqs (quasithreshold doses) of the radiation survival curves were 5.39, 3.28, 2.13 and 0.54Gy, although the Dos (37% dose slopes) of the radiation survival curves were 2.55, 2.49, 2.39 and 2.18 Gy, when combination treatment with radiaiton and 0, 5, 10 and 20 mug/ml of Etoposide, respectively, was carried out. The cytotoxic effect became increased when fractional treatments with Etoposide and radiation were performed. The results obtained suggest that the mechanism of the interactive cytotoxic effect of this combination treatment involves a reciprocal action of Etoposide and sublethal damage by the radiation to the cells. (author).

  9. The Protective Effect of Silybin against Lasalocid Cytotoxic Exposure on Chicken and Rat Cell Lines

    Directory of Open Access Journals (Sweden)

    Lidia Radko

    2013-01-01

    Full Text Available Lasalocid, an ionophore coccidiostat, extensive use implies a risk of toxicological impacts. Protective effects of silybin, a herbal compound of Silybum marianum, are reported elsewhere. The aim of this study was to compare effects of the combined use of lasalocid and silybin in chicken hepatoma cells (LMH and rat myoblasts (L6 cell lines cultures. The cytoprotective effect resulting from an interaction of both pharmaceuticals was measured with the help of MTT reduction and, coomassie brilliant blue binding (CBB and LDH release assays. Isobolography and the combination index (CI estimated the nature and scale of interaction. In all performed tests, the lowest lasalocid EC50-values were obtained for chicken hepatocytes. In the rat myoblasts cultures, the lowest lasalocid EC50-values were found with LDH test. Simultaneously, a lack of silybin cytotoxic effect was proven for the studied cell lines. An interaction between both substances led to a considerable decrease of lasalocid cytotoxicity. The isobolograms and combination index showed a significant antagonistic nature of silybin effect in the course of lasalocid cytotoxicity. It is concluded that the mechanism of cytoprotection results from complex reaction at biochemical and biophysical endpoints during chicken hepatocytes and rat myoblasts cell lines exposure to silybin and lasalocid co-action.

  10. Studies on the cytotoxicity of diamond nanoparticles against human cancer cells and lymphocytes.

    Science.gov (United States)

    Adach, Kinga; Fijalkowski, Mateusz; Gajek, Gabriela; Skolimowski, Janusz; Kontek, Renata; Blaszczyk, Alina

    2016-07-25

    Detonation nanodiamonds (DND) are a widely studied group of carbon nanomaterials. They have the ability to adsorb a variety of biomolecules and drugs onto their surfaces, and additionally their surfaces may be subjected to chemical functionalization by covalent bonds. We present a procedure for the purification and surface oxidation of diamond nanoparticles, which were then tested by spectroscopic analysis such as ATR-FTIR, Raman spectroscopy, and thermogravimetric analysis. We also examined the zeta potential of the tested material. Analysis of the cytotoxic effect of nanodiamonds against normal lymphocytes derived from human peripheral blood, the non-small cell lung cancer cell line (A549) and the human colorectal adenocarcinoma cell line (HT29) was performed using MTT colorimetric assay. Evaluation of cell viability was performed after 1-h and 24-h treatment with the tested nanoparticles applied at concentrations ranging from 1 μg/ml to 100 μg/ml. We found that the survival of the examined cells was strongly associated with the presence of serum proteins in the growth medium. The incubation of cells with nanodiamonds in the presence of serum did not exert a significant effect on cell survival, while the cell treatment in a serum-free medium resulted in a decrease in cell survival compared to the negative control. The role of purification and functionalization of nanodiamonds on their cytotoxicity was also demonstrated. PMID:27270448

  11. FOXP3-specific immunity

    OpenAIRE

    Andersen, Mads Hald

    2013-01-01

    Forkhead box P3 (FOXP3)-specific cytotoxic CD8+ T cells are present among human peripheral blood mononuclear cells (PBMCs), especially in cancer patients. Such T lymphocytes are able not only to specifically recognize dendritic cells (DCs) that have been exposed to recombinant FOXP3 and regulatory T cells, but also to kill FOXP3+ malignant T cells. The natural occurrence of FOXP3-specific cytotoxic T lymphocytes among human PBMCs suggests a general role for these cells in the complex network ...

  12. Uptake and cytotoxic effects of multi-walled carbon nanotubes in human bronchial epithelial cells

    International Nuclear Information System (INIS)

    Carbon nanotubes (CNT) are cytotoxic to several cell types. However, the mechanism of CNT toxicity has not been fully studied, and dosimetric analyses of CNT in the cell culture system are lacking. Here, we describe a novel, high throughput method to measure cellular uptake of CNT using turbimetry. BEAS-2B, a human bronchial epithelial cell line, was used to investigate cellular uptake, cytotoxicity, and inflammatory effects of multi-walled CNT (MWCNT). The cytotoxicity of MWCNT was higher than that of crocidolite asbestos in BEAS-2B cells. The IC50 of MWCNT was 12 μg/ml, whereas that of asbestos (crocidolite) was 678 μg/ml. Over the course of 5 to 8 h, BEAS-2B cells took up 17-18% of the MWCNT when they were added to the culture medium at a concentration of 10 μg/ml. BEAS-2B cells were exposed to 2, 5, or 10 μg/ml of MWCNT, and total RNA was extracted for cytokine cDNA primer array assays. The culture supernatant was collected for cytokine antibody array assays. Cytokines IL-6 and IL-8 increased in a dose dependent manner at both the mRNA and protein levels. Migration inhibitory factor (MIF) also increased in the culture supernatant in response to MWCNT. A phosphokinase array study using lysates from BEAS-2B cells exposed to MWCNT indicated that phosphorylation of p38, ERK1, and HSP27 increased significantly in response to MWCNT. Results from a reporter gene assays using the NF-κB or AP-1 promoter linked to the luciferase gene in transiently transfected CHO-KI cells revealed that NF-κB was activated following MWCNT exposure, while AP-1 was not changed. Collectively, MWCNT activated NF-κB, enhanced phosphorylation of MAP kinase pathway components, and increased production of proinflammatory cytokines in human bronchial epithelial cells.

  13. Synergistic cytotoxic effects of antibodies directed against different cell surface determinants

    International Nuclear Information System (INIS)

    Three antibody populations were raised in rabbits against surface antigens on guinea-pig L2C leukaemic lymphocytes: against idiotypic determinants on the lambda chain of the surface immunoglobulin, against C region determinants on the lambda chain, and against the surface antigens recognised by conventional anti-lymphocyte sera. Complement and K-cell cytotoxicities effected by the antibodies on L2C cells were studied in vitro. In both cytotoxic systems mixtures of the antibodies revealed synergy, in that the titres of the mixtures exceeded predicted additive titres of their components. The synergy was greater when the mixed antibodies were directed to determinants on the same molecule rather than to determinants on different molecules. (author)

  14. Cytotoxic mechanism of flavonoid from Temu Kunci (Kaempferia pandurata) in cell culture of human mammary carcinoma.

    Science.gov (United States)

    Sukardiman; Darwanto, A; Tanjung, M; Darmadi, M O

    2000-01-01

    The cytotoxic activity of flavonoid from Temu Kunci (Kaempferia pandurata) was tested by brine shrimp lethality test and cell culture of human mammary carcinoma. This compound is pinostrobin, and has antitumor activity. However, the critical biochemical target of these pinostrobin has not been identified. In our present studies, we used DNA topoisomerase I which was isolated from human tumor. This result showed that pinostrobin inhibited DNA topoisomerase I activity. Pinostrobin may be interfere with DNA breakage-reunion reaction by stabilizing a key covalent intermediate between DNA and the enzyme, resulting in the cleavage DNA. An inhibition in the activity of DNA topoisomerase I is suggesting that this could be a possible mechanism of pinostrobin from Temu Kunci for the cytotoxicity observed in cell culture of human mammary carcinoma. PMID:11321439

  15. Cytotoxicity evaluation of self-etching dentine bonding agents in a cell culture perfusion condition

    OpenAIRE

    Korsuwannawong, Suwanna; Srichan, Ratchaporn; Vajrabhaya, La-Ongthong

    2012-01-01

    Objective: The aim of this study was to evaluate the cytotoxicity of three dentine bonding agents (G-Bond, Clearfil S3 Bond and Clearfil SE Bond X) in cell-culture perfusion. Methods: In this experiment, 8×104 TCPC SV40 cells (bovine-pulp-derived cells transfected with simian virus 40 large T-antigen) in MEM-alpha media, 20%FCS were seeded on mesh in a 6-well plate and incubated at 37 °C with 5% CO2. After 2 days, the mesh inserts were transferred to a 24-well plate and incubated in MEM-alpha...

  16. Phytic acid protects porcine intestinal epithelial cells from deoxynivalenol (DON) cytotoxicity.

    OpenAIRE

    Pacheco, Graziela Drociunas; Silva, Caio Abércio da; Pinton, Philippe; Oswald, Isabelle

    2012-01-01

    The purpose of this study was to evaluate the effects of phytic acid (IP(6)) as a possible inhibitor of cellular damage induced by toxic substances such as mycotoxins on a porcine intestinal epithelial cell line (IPEC-1). We first observed that a dose of 5 mM phytic acid decreases cell viability and transepithelial electrical resistance (TEER) of cell monolayer. We next investigate the effect of non-cytotoxic dose of phytic acid on the deoxinivalenol (DON) induced decreased TEER. We showed th...

  17. The cytotoxic effects a of ACA1 on human melanoma cell line

    OpenAIRE

    R. Yaraie; M.R. Jalali Nadoushan; Naseri, M.; S. Shahrokhi; T. Ghazanfari; Kardar, M.

    2006-01-01

    Background and purpose: Different methods such as surgery, chemotherapy, radiotherapy, hormone therapy and immunotherapy are used for treatment of melanoma cancer. Unfortunately they don't always have desirable results and they may have unfavorable side effects. Researchers try to find new, more effective drugs with low side effects. In this study we evaluated the cytotoxic effect of ACA-1, a water extract of a traditional Iranian medicinal herbs on a melanoma cell line SKMEL-3.Materials and ...

  18. In-vitro screening of organotin compounds and sediment extracts for cytotoxicity to fish cells

    OpenAIRE

    Giltrap, Michelle; Macken, Ailbhe; McHugh, Brendan; McGovern, Evin; Foley, Barry; Davoren, Maria

    2011-01-01

    The present study reports an in vitro screening method for contaminants in sediment samples utilizing an RTG-2 cell line. This technique integrates cytotoxicity testing with analytical chemistry with the aim of achieving a toxicity evaluation of the sediment sample. The toxic effect of individual organotin (OT) compounds and their presence in the sediment sample is the focus of the present study; however, other contaminants are also discussed. The following OT compounds: tributyltin (TBT), di...

  19. Unraveling the response of plant cells to cytotoxic saponins: Role of metallothionein and nitric oxide

    OpenAIRE

    Balestrazzi, Alma; Macovei, Anca; Tava, Aldo; Avato, Pinarosa; Raimondi, Elena; Daniela CARBONERA

    2011-01-01

    A wide range of pharmacological properties are ascribed to natural saponins, in addition to their biological activities against herbivores, plant soil-borne pathogens and pests. As for animal cells, the cytotoxicity and the chemopreventive role of saponins are mediated by a complex network of signal transduction pathways which include reactive oxygen species (ROS) and nitric oxide (NO). The involvement of other relevant components of the saponin-related signaling routes, such as the Tumor Nec...

  20. Cytotoxicity activities of chloroform extract of Cichorium intybus seed against HCT-15 and Vero cell line

    OpenAIRE

    Prashant Y Mali

    2015-01-01

    Background: Cichorium intybus L., (Asteraceae) is well-known as a coffee substitute but is also widely used medicinally to treat various ailments ranging from wounds to diabetes. Other plant parts are also used for liver and cancer disorder. Objective: The objective was to study the cytotoxic potential of chloroform extract of C. intybus seed against HCT-15 and Vero (normal) cell line. Materials and Methods: Fourier transform infrared spectroscopy (FTIR) analysis of the extract was performed....

  1. Evaluation of cytotoxicity of Moringa oleifera Lam. callus and leaf extracts on Hela cells

    OpenAIRE

    Abbas Jafarain; Gholamreza Asghari; Erfaneh Ghassami

    2014-01-01

    Background: There are considerable attempts worldwide on herbal and traditional compounds to validate their use as anti-cancer drugs. Plants from Moringaceae family including Moringa oleifera possess several activities such as antitumor effect on tumor cell lines. In this study we sought to determine if callus and leaf extracts of M. oleifera possess any cytotoxicity. Materials and Methods: Ethanol-water (70-30) extracts of callus and leaf of M. oleifera were prepared by maceration method...

  2. Cytotoxic effect of Argentine medicinal plant extracts on human hepatocellular carcinoma cell line.

    Science.gov (United States)

    Ruffa, M J; Ferraro, G; Wagner, M L; Calcagno, M L; Campos, R H; Cavallaro, L

    2002-03-01

    Methanolic extracts from Achyrocline satureioides (Dc.) Lam, Aristolochia macroura Gomez, Lithraea molleoides (Vell.) Engl., Schinus molle L., unlike those from Celtis spinosa Spreng, Chenopodium ambrosioides L., Petiveria alliacea L., and Plantago major L. showed cytotoxic activity against a human hepatocellular carcinoma cell line, Hep G2. Schinus molle L. was the most active (IC50=50+/-7 microg/ml). These results call for further studies of these extracts. PMID:11849838

  3. Regulatory T Cells and IL-10 Independently Counterregulate Cytotoxic T Lymphocyte Responses Induced by Transcutaneous Immunization

    OpenAIRE

    Pamela Stein; Michael Weber; Steve Prüfer; Beate Schmid; Edgar Schmitt; Hans-Christian Probst; Ari Waisman; Peter Langguth; Hansjörg Schild; Markus P Radsak

    2011-01-01

    BACKGROUND: The imidazoquinoline derivate imiquimod induces inflammatory responses and protection against transplanted tumors when applied to the skin in combination with a cognate peptide epitope (transcutaneous immunization, TCI). Here we investigated the role of regulatory T cells (T(reg)) and the suppressive cytokine IL-10 in restricting TCI-induced cytotoxic T lymphocyte (CTL) responses. METHODOLOGY/PRINCIPAL FINDINGS: TCI was performed with an ointment containing the TLR7 agonist imiqui...

  4. Analysis of cytotoxic T cell epitopes in relation to cancer

    DEFF Research Database (Denmark)

    Stranzl, Thomas

    kill the infected cells. The focus of my PhD project has been on improving a method for CTL epitope pathway prediction, on analyzing the epitope density in the alternative cancer exome, and on a study investigating minor histocompatibility antigens (mHags) associated with leukemia. Part I......CTL methods, the experimental effort to identify 90% of new epitopes can be reduced by 15% and 40%, respectively. Part III reports the results of an analysis investigating how the alternatively spliced cancer exome differs from the exome of normal tissue in terms of containing predicted MHC class I binding...... epitopes. We show that peptides unique to cancer splice variants comprise significantly fewer predicted HLA class I epitopes than peptides unique to spliced transcripts in normal tissue. We furthermore find that hydrophilic amino acids are significantly enriched in the unique carcinoma sequences, which...

  5. Non-cytotoxic Thymus capitata extracts prevent Bovine herpesvirus-1 infection in cell cultures

    OpenAIRE

    Boubaker–Elandalousi, Ramzi; Mekni–Toujani, Marwa; Kaabi, Belhassen; Larbi, Imen; Diouani, Mohamed-Fethi; Gharbi, Mohamed; Akkari, Hafidh; B’chir, Fatma; Ghram, Abdeljelil

    2014-01-01

    Background Bovine herpes virus type 1 (BHV-1) still causes great economic loss to the livestock industry and trade because there aren’t any available drugs that proved to be fully effective against it. In this study, the cytotoxicity and the antiviral activities of the Thymus capitata extracts were evaluated for the development of new, non toxic and specific anti-herpesvirus drug. Aqueous extracts (AE), ethanolic extracts (EE) and essential oil (EO) of the aerial parts of Thymus capitata were...

  6. Cytotoxic Effects of Newly Synthesized Palladium(II Complexes of Diethyldithiocarbamate on Gastrointestinal Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Shahram Hadizadeh

    2014-01-01

    Full Text Available As a part of a drug development program to discover novel therapeutic and more effective palladium (Pd based anticancer drugs, a series of water-soluble Pd complexes have been synthesized by interaction between [Pd (phen(H2O2(NO32] and alkylenebisdithiocarbamate(al-bis-dtc disodium salts. This study was undertaken to examine the possible cytotoxic effect of three novel complexes (0.125–64 µg/mL on human gastric carcinoma (AGS, esophageal squamous cell carcinoma (Kyse-30, and hepatocellular carcinoma (HepG2 cell lines. The cytotoxicity was examined using cell proliferation and acridine orange/ethidium bromide (AO/EB assay. In order to examine the effects of new Pd(II complexes on cell cycle status, we performed cell cycle analysis. The complexes were found to have completely lethal effects on the cell lines, and the half maximal inhibitory concentration (IC50 values obtained for the cell lines were much lower in comparison with cisplatin. We demonstrated that the three new Pd(II complexes are able to induce G2/M phase arrest in AGS and HepG2; in addition, the Pd(II complexes caused an S phase arrest in Kyse-30 cell line. Our results indicate that newly synthesized Pd(II complexes may provide a novel class of chemopreventive compounds for anticancer therapy.

  7. Cytotoxic effects of Gemcitabine-loaded liposomes in human anaplastic thyroid carcinoma cells

    Directory of Open Access Journals (Sweden)

    Rotiroti Domenicoantonio

    2004-09-01

    Full Text Available Abstract Background Identification of effective systemic antineoplastic drugs against anaplastic thyroid carcinomas has particularly important implications. In fact, the efficacy of the chemotherapeutic agents presently used in these tumours, is strongly limited by their low therapeutic index. Methods In this study gemcitabine was entrapped within a pegylated liposomal delivery system to improve the drug antitumoral activity, thus exploiting the possibility to reduce doses to be administered in cancer therapy. The cytotoxic effects of free or liposome-entrapped gemcitabine was evaluated against a human thyroid tumour cell line. ARO cells, derived from a thyroid anaplastic carcinoma, were exposed to different concentrations of the drug. Liposomes formulations were made up of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol/1,2-distearoyl-sn-glycero-3-phosphoethanolamine-MPEG (8:3:1 molar ratio. Cell viability was assessed by both trypan bleu dye exclusion assay and fluorimetric analysis of cell DNA content. Results A cytotoxic effect of free gemcitabine was present only after 72 h incubation (ARO cell mortality increased of approximately 4 fold over control at 1 μM, 7 fold at 100 μM. When gemcitabine was encapsulated in liposomes, a significant effect was observed by using lower concentrations of the drug (increased cell mortality of 2.4 fold vs. control at 0.3 μM and earlier exposure time (24 h. Conclusion These findings show that, in vitro against human thyroid cancer cells, the gemcitabine incorporation within liposomes enhances the drug cytotoxic effect with respect to free gemcitabine, thus suggesting a more effective drug uptake inside the cells. This may allow the use of new formulations with lower dosages (side effect free for the treatment of anaplastic human thyroid tumours.

  8. Cytotoxic activities of Euphorbia kopetdaghi against OVCAR-3 and EJ-138 cell lines

    Directory of Open Access Journals (Sweden)

    Aghaei Mahmoud

    2015-04-01

    Full Text Available Introduction: Over the centuries, the genus Euphorbia was known to be toxic to humans and animals. Recently, in a primary study significant suppressive activity against phytohemagglutinin activated T-cell proliferation has been reported from this plant. Therefore, this study was designed to evaluate the cytotoxic effects of different parts of E. kopetdaghi against cancer cell lines. Methods: Filtration and in vacuo concentration resulted in a green gum which was subjected on silica gel CC (hexane/Acetone, 0→50 to several fractions: F1-F8. The inhibitory effects of obtained fractions with 5, 50, and 500 μg/ml concentrations were evaluated on proliferation and viability of cancer cells (OVCAR and EJ-138 in 48 hours treatment. Finally, cell viability was determined at a wavelength of 570 by 3-4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT method. Results: Based on studies of microscopic observation and viability testing, F1, F2, F4, F5, F6, and F7 showed significant cytotoxic effect at concentration of 50 and 500 μg/ml against EJ-138 and OVCAR-3 cell lines. These fractions inhibited growth of EJ-138 and OVCAR-3 cells in a concentration-dependent manner. Fraction of F8 induced tumor promotion significantly in EJ-138 and OVCAR-3 cells, respectively. Conclusion: Due to the inhibitory properties of E. kopetdaghi extract and its fractions on cancer cells of OVCAR3 and EJ-13, isolation, purification and identification of compounds presented in the fractions possessing cytotoxic effects are recommended which were the area of our future research.

  9. Catalytic nanomedicine technology: copper complexes loaded on titania nanomaterials as cytotoxic agents of cancer cell.

    Science.gov (United States)

    Lopez, Tessy; Ortiz-Islas, Emma; Guevara, Patricia; Gómez, Esteban

    2013-01-01

    The anticancer properties of pure copper (II) acetate and copper (II) acetylacetonate, alone and loaded on functionalized sol-gel titania (TiO(2)), were determined in four different cancer cell lines (C6, RG2, B16, and U373), using increasing concentrations of these compounds. The copper complexes were loaded onto the TiO(2) network during its preparation by the solgel process. Once copper-TiO(2) materials were obtained, these were characterized by several physical-chemical techniques. An in vitro copper complex-release test was developed in an aqueous medium at room temperature and monitored by ultraviolet spectroscopy. The toxic effect of the copper complexes, alone and loaded on TiO(2), was determined using a cell viability 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay, when cancer cells were treated with increasing concentrations (15.75-1000 mg/mL) of these. Characterization studies revealed that the addition of copper complexes to the TiO(2) sol-gel network during its preparation, did not generate changes in the molecular structure of the complexes. The surface area, pore volume, and pore diameter were affected by the copper complex additions and by the crystalline phases obtained. The kinetic profiles of both copper complexes released indicated two different stages of release: The first one was governed by first-order kinetics and the second was governed by zero-order kinetics. The cell viability assay revealed a cytotoxic effect of copper complexes, copper-TiO(2), and cisplatin in a dose-dependent response for all the cell lines; however, the copper complexes exhibited a better cytotoxic effect than the cisplatin compound. TiO(2) alone presented a minor cytotoxicity for C6 and B16 cells; however, it did not cause any toxic effect on the RG2 and U373 cells, which indicates its high biocompatibility with these cells. PMID:23413123

  10. Cytotoxic effects of Gemcitabine-loaded liposomes in human anaplastic thyroid carcinoma cells

    International Nuclear Information System (INIS)

    Identification of effective systemic antineoplastic drugs against anaplastic thyroid carcinomas has particularly important implications. In fact, the efficacy of the chemotherapeutic agents presently used in these tumours, is strongly limited by their low therapeutic index. In this study gemcitabine was entrapped within a pegylated liposomal delivery system to improve the drug antitumoral activity, thus exploiting the possibility to reduce doses to be administered in cancer therapy. The cytotoxic effects of free or liposome-entrapped gemcitabine was evaluated against a human thyroid tumour cell line. ARO cells, derived from a thyroid anaplastic carcinoma, were exposed to different concentrations of the drug. Liposomes formulations were made up of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol/ 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-MPEG (8:3:1 molar ratio). Cell viability was assessed by both trypan bleu dye exclusion assay and fluorimetric analysis of cell DNA content. A cytotoxic effect of free gemcitabine was present only after 72 h incubation (ARO cell mortality increased of approximately 4 fold over control at 1 μM, 7 fold at 100 μM). When gemcitabine was encapsulated in liposomes, a significant effect was observed by using lower concentrations of the drug (increased cell mortality of 2.4 fold vs. control at 0.3 μM) and earlier exposure time (24 h). These findings show that, in vitro against human thyroid cancer cells, the gemcitabine incorporation within liposomes enhances the drug cytotoxic effect with respect to free gemcitabine, thus suggesting a more effective drug uptake inside the cells. This may allow the use of new formulations with lower dosages (side effect free) for the treatment of anaplastic human thyroid tumours

  11. Selective cytotoxic effect of 1-O-undecylglycerol in human melanoma cells

    Directory of Open Access Journals (Sweden)

    Marian Hernández-Colina

    2016-04-01

    Full Text Available Context: 1-O-alkylglycerols are ether-linked glycerols derived from shark liver oil and found in small amounts in human milk. Previous studies showed antineoplastic activity for this family of compounds, structurally related to alkylphospholipids, but the activity of linear chain synthetic alkylglycerols in cancer cell lines is less documented. Melanoma is a high incidence cancer, highly resistant to potential treatments. Finding new anti-cancer compounds to improve melanoma prognosis is a relevant research issue. Aims: To study the cytotoxic effect of 1-O-undecylglycerol in primary cultured normal fibroblasts and A375 human melanoma cell line. Methods: Cells were treated with different concentrations of 1-O-undecylglycerol and viability assessed by MTT assay. Morphological changes were visualized by DAPI and acridine orange-ethidium bromide staining. Mitochondrial membrane potential was evaluated, and gene expression of P53 and BcL-2 was semi-quantified. Results: 1-O-undecylglycerol decreased viability of A375 cells and exerted very low cytotoxicity on primary cultured normal fibroblasts. Necrosis appeared in A375 cells but not in fibroblasts, and no apoptotic changes were visualized in DAPI staining experiments. After 24 h fibroblasts and melanoma cells developed mitochondrial potential changes similar to valinomycin. The gene expression of P53 and BcL-2 decreased in treated cells. Conclusions: 1-O-undecylglycerol exhibited selective cytotoxic activity in A375 melanoma cells when compared with primary cultured fibroblast. Its toxicity is mediated by necrosis that may be related with mitochondrial events and decrease in P53 and BcL-2 expression. The results suggest that UDG could be a useful strategy to combine with other chemotherapeutic agents in melanoma treatment.

  12. Nanoliposomal formulation of Agrostemma githago aqueous extract shows enhanced cytotoxic effect on gastric cancer cell line

    Directory of Open Access Journals (Sweden)

    Shahab Bohlooli

    2015-01-01

    Full Text Available Objective(s: The objective of this study was to determine the cytotoxic effects of nanoliposomal form of lyophilized aqueous extract of Agrostemma githago (A. githago seeds on gastric cancer cell line (AGS using cell viability tests. Materials and Methods: Lyophilized aqueous extract of A. githago seeds was prepared. Liposomes were also prepared by thin-film hydration method and their stability and size were characterized by SEM. The size and zeta potential were determined by Malvern Zetasizer. Cytotoxic effects of nanoliposomes on gastric cancer cell line was determined using MTT, Neutral Red and Frame methods. Results: The size of liposomes was around 171.5 nm with proper dispersion (PDI=0.268. The morphology of the liposomes was suitable according to SEM images. The IC50 values indicated that the nanoliposomal form of extract was 3-4 times more active than extract alone. Average IC50 values for extract and liposomal form of extract were 13.02 ± 0.95 and 4.43 ± 1.49 ug/ml, respectively. Conclusion: This study showed that liposomal form of aqueous extract of A. githago seeds exerts cytotoxic effect at significantly lower concentrations than the extract itself.

  13. Modulation of Tamoxifen Cytotoxicity by Caffeic Acid Phenethyl Ester in MCF-7 Breast Cancer Cells.

    Science.gov (United States)

    Motawi, Tarek K; Abdelazim, Samy A; Darwish, Hebatallah A; Elbaz, Eman M; Shouman, Samia A

    2016-01-01

    Although Tamoxifen (TAM) is one of the most widely used drugs in managing breast cancer, many women still relapse after long-term therapy. Caffeic acid phenethyl ester (CAPE) is a polyphenolic compound present in many medicinal plants and in propolis. The present study examined the effect of CAPE on TAM cytotoxicity in MCF-7 cells. MCF-7 cells were treated with different concentrations of TAM and/or CAPE for 48 h. This novel combination exerted synergistic cytotoxic effects against MCF-7 cells via induction of apoptotic machinery with activation of caspases and DNA fragmentation, along with downregulation of Bcl-2 and Beclin 1 expression levels. However, the mammalian microtubule-associated protein light chain LC 3-II level was unchanged. Vascular endothelial growth factor level was also decreased, whereas levels of glutathione and nitric oxide were increased. In conclusion, CAPE augmented TAM cytotoxicity via multiple mechanisms, providing a novel therapeutic approach for breast cancer treatment that can overcome resistance and lower toxicity. This effect provides a rationale for further investigation of this combination. PMID:26697130

  14. Reaction between nitracrine and glutathione: implications for hypoxic cell radiosensitization and cytotoxicity

    International Nuclear Information System (INIS)

    Nitracrine (NC) is an electron affinic DNA intercalating agent and a potent hypoxia-selective cytotoxin and radiosensitizer in cell culture. Although NC is too cytotoxic and too rapidly metabolized to provide hypoxic cell radiosensitization in tumors, it is of mechanistic interest as an example of a DNA affinic radiosensitizer. We have observed a rapid chemical reaction between NC and reduced glutathione (GSH), which suggests that the observed potent in vitro cytotoxicity and radiosensitization might be dependent on thiol depletion by the large extracellular reservoir of drug. However, no GSH depletion was observed under conditions providing radiosensitization or rapid cell killing, and prior depletion of GSH by buthionine sulphoximine had no effect on cytotoxicity or formation of macromolecular adducts. Further, the intracellular reaction of NC with GSH is slower than predicted on the basis of the measured second order rate constant and the total intracellular concentrations of both species. The results are consistent with a role for DNA binding in protecting NC from reaction with GSH, and in improving the efficiency with which reduced electrophilic metabolites react with DNA in preference to GSH

  15. Combined cytotoxic effects of pesticide mixtures present in the Chinese diet on human hepatocarcinoma cell line.

    Science.gov (United States)

    Ma, Mengmeng; Chen, Chen; Yang, Guiling; Li, Yun; Chen, Zhijun; Qian, Yongzhong

    2016-09-01

    Consumers might be simultaneously exposed to several pesticide residues contained in their food. Based on the results of previous studies, 20 pesticides were selected due to their high exposure levels to which the Chinese population is likely exposed through the diet. The purpose of this study was to measure the cytotoxicity of these pesticides in HepG2 cells in vitro, as an alternative approach to assess the toxicity of chemicals. Then, the pesticides and some of the mixtures with comparatively high cell-proliferating inhibitory activities were selected to test the cellular ROS level and apoptosis-related protein Caspase-3/7 content in HepG2 cells. The combined effects of these pesticide mixtures with the prediction was based on a combination index (CI)-isobologram equation and the pesticide combinations exhibited various types of interactions (synergism, antagonism, and additivity). Two individuals, one binary combinations, and three uniform design (UD) mixtures of the pesticides were found to have significant cytotoxic effects, along with significant time- and dose-dependent induction of caspase-3/7 activity in vitro, indicating that cytotoxicity caused by these pesticides might be attributed to the pro-oxidative and apoptosis induced potential. PMID:27300773

  16. Effect of linear alkylbenzene sulfonate (LAS) on human intestinal Caco-2 cells at non cytotoxic concentrations.

    Science.gov (United States)

    Bradai, Mohamed; Han, Junkyu; Omri, Abdelfatteh El; Funamizu, Naoyuki; Sayadi, Sami; Isoda, Hiroko

    2016-08-01

    Linear alkylbenzene sulfonate (LAS) is a cytotoxic synthetic anionic surfactant widely present in the environment due to its large-scale production and intensive use in the detergency field. In this study, we investigated the effect of LAS (CAS No. 25155-30-0) at non cytotoxic concentrations on human intestinal Caco-2 cells using different in vitro bioassays. As results, LAS increased Caco-2 cell proliferation at concentrations ranging from 1 to 15 ppm, more significantly for shorter exposure time (24 h), confirmed using flow cytometry and trypan blue exclusion methods. Moreover, proteomics analysis revealed that this effect was associated with an over-expression of elongation factor 2 and dipeptidyl peptidase 3, and a down-regulation of 14-3-3 protein theta, confirmed at mRNA level using real-time PCR. These findings suggest that LAS at non cytotoxic concentrations, similar to those observed at wastewater treatment plants outlets, increases the growth rate of colon cancer cells, raising thereby its tumor promotion effect potential. PMID:25999174

  17. Modulation of Tamoxifen Cytotoxicity by Caffeic Acid Phenethyl Ester in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Tarek K. Motawi

    2016-01-01

    Full Text Available Although Tamoxifen (TAM is one of the most widely used drugs in managing breast cancer, many women still relapse after long-term therapy. Caffeic acid phenethyl ester (CAPE is a polyphenolic compound present in many medicinal plants and in propolis. The present study examined the effect of CAPE on TAM cytotoxicity in MCF-7 cells. MCF-7 cells were treated with different concentrations of TAM and/or CAPE for 48 h. This novel combination exerted synergistic cytotoxic effects against MCF-7 cells via induction of apoptotic machinery with activation of caspases and DNA fragmentation, along with downregulation of Bcl-2 and Beclin 1 expression levels. However, the mammalian microtubule-associated protein light chain LC 3-II level was unchanged. Vascular endothelial growth factor level was also decreased, whereas levels of glutathione and nitric oxide were increased. In conclusion, CAPE augmented TAM cytotoxicity via multiple mechanisms, providing a novel therapeutic approach for breast cancer treatment that can overcome resistance and lower toxicity. This effect provides a rationale for further investigation of this combination.

  18. Cytotoxicity of graphene oxide and graphene oxide loaded with doxorubicin on human multiple myeloma cells

    Directory of Open Access Journals (Sweden)

    Wu S

    2014-03-01

    Full Text Available Shaoling Wu,1 Xindong Zhao,2 Zhongguang Cui,1 Chunting Zhao,1 Yuzhen Wang,1 Li Du,1 Yanhui Li3 1Department of Hematology, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, Shandong, People's Republic of China; 2Department of Hematology, Medical College of Qingdao University, Qingdao, Shandong, People's Republic of China; 3Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, Qingdao University, Qingdao, Shandong, People's Republic of China Abstract: The purpose of this study was to evaluate the cytotoxicity of human multiple myeloma cells (RPMI-8226 treated with graphene oxide (GO, doxorubicin (DOX, and GO loaded with DOX (GO/DOX. Cell viability was determined using the Cell Counting Kit-8 assay and analyzing the cell cycle and cell apoptosis. Cells treated with GO, GO/DOX, and pure DOX for 24 hours showed a decrease in proliferation. GO/DOX significantly inhibited cell proliferation as compared with pure DOX (P<0.01. When the effects of GO were removed, there was no observed difference between GO/DOX and pure DOX (P>0.05. Flow cytometry analysis of untreated and GO-, DOX-, and GO/DOX-treated cells found no significant differences in the G0/G1 phase (P>0.05, while significant differences were observed in the total apoptotic rates (P<0.05. No significant differences existed in the total apoptotic rates of GO-treated and untreated cells (P>0.05. These findings suggest that GO caused low cytotoxicity and did not induce cell apoptosis or change the cell cycle in multiple myeloma cells. Moreover, GO did not affect the antitumor activity of DOX. In conclusion, GO would be suitable as an anticancer drug nanocarrier and used to treat hematological malignancies. Keywords: graphene oxide, doxorubicin, human multiple myeloma cell, CCK-8, cell cycle, cell apoptosis

  19. Cell type-dependent uptake, localization, and cytotoxicity of 1.9 nm gold nanoparticles

    Directory of Open Access Journals (Sweden)

    Coulter JA

    2012-06-01

    Full Text Available Jonathan A Coulter,1 Suneil Jain,2 Karl T Butterworth,2 Laura Taggart,2 Glenn Dickson,2 Stephen J McMahon,3 Wendy Hyland,1 Mark F Muir,3 Coleman Trainor,2 Alan Hounsell,2,4 Joe M O'Sullivan,2,4 Giuseppe Schettino,2 Fred Currell,3 David G Hirst,1 Kevin M Prise21School of Pharmacy, McClay Research Centre, 2Centre for Cancer Research and Cell Biology, 3School of Mathematics and Physics, Queens University Belfast, 4Belfast Health and Social Care Trust, Belfast, IrelandBackground: This follow-up study aims to determine the physical parameters which govern the differential radiosensitization capacity of two tumor cell lines and one immortalized normal cell line to 1.9 nm gold nanoparticles. In addition to comparing the uptake potential, localization, and cytotoxicity of 1.9 nm gold nanoparticles, the current study also draws on comparisons between nanoparticle size and total nanoparticle uptake based on previously published data.Methods: We quantified gold nanoparticle uptake using atomic emission spectroscopy and imaged intracellular localization by transmission electron microscopy. Cell growth delay and clonogenic assays were used to determine cytotoxicity and radiosensitization potential, respectively. Mechanistic data were obtained by Western blot, flow cytometry, and assays for reactive oxygen species.Results: Gold nanoparticle uptake was preferentially observed in tumor cells, resulting in an increased expression of cleaved caspase proteins and an accumulation of cells in sub G1 phase. Despite this, gold nanoparticle cytotoxicity remained low, with immortalized normal cells exhibiting an LD50 concentration approximately 14 times higher than tumor cells. The surviving fraction for gold nanoparticle-treated cells at 3 Gy compared with that of untreated control cells indicated a strong dependence on cell type in respect to radiosensitization potential.Conclusion: Gold nanoparticles were most avidly endocytosed and localized within cytoplasmic

  20. Increased betulinic acid induced cytotoxicity and radiosensitivity in glioma cells under hypoxic conditions

    International Nuclear Information System (INIS)

    Betulinic acid (BA) is a novel antineoplastic agent under evaluation for tumor therapy. Because of the selective cytotoxic effects of BA in tumor cells (including gliomas), the combination of this agent with conservative therapies (such as radiotherapy and chemotherapy) may be useful. Previously, the combination of BA with irradiation under hypoxic conditions had never been studied. In this study, the effects of 3 to 30 μM BA on cytotoxicity, migration, the protein expression of PARP, survivin and HIF-1α, as well as radiosensitivity under normoxic and hypoxic conditions were analyzed in the human malignant glioma cell lines U251MG and U343MG. Cytotoxicity and radiosensitivity were analyzed with clonogenic survival assays, migration was analyzed with Boyden chamber assays (or scratch assays) and protein expression was examined with Western blot analyses. Under normoxic conditions, a half maximal inhibitory concentration (IC50) of 23 μM was observed in U251MG cells and 24 μM was observed in U343MG cells. Under hypoxic conditions, 10 μM or 15 μM of BA showed a significantly increased cytotoxicity in U251MG cells (p = 0.004 and p = 0.01, respectively) and U343MG cells (p < 0.05 and p = 0.01, respectively). The combination of BA with radiotherapy resulted in an additive effect in the U343MG cell line under normoxic and hypoxic conditions. Weak radiation enhancement was observed in U251MG cell line after treatment with BA under normoxic conditions. Furthermore, under hypoxic conditions, the incubation with BA resulted in increased radiation enhancement. The enhancement factor, at an irradiation dose of 15 Gy after treatment with 10 or 15 μM BA, was 2.20 (p = 0.02) and 4.50 (p = 0.03), respectively. Incubation with BA led to decreased cell migration, cleavage of PARP and decreased expression levels of survivin in both cell lines. Additionally, BA treatment resulted in a reduction of HIF-1α protein under hypoxic conditions. Our results suggest that BA is capable of

  1. Cytotoxic T lymphocyte control during ectromelia (mousepox) virus infection: Interaction between MHC-restricted cells analyzed by non-radioactive-fluorimetry

    International Nuclear Information System (INIS)

    Cytotoxic T lymphocyte activity of draining lymph node cells isolated from BALB/c mice infected with ectromelia virus (EV) was examined using a fluorometric cell-mediated cytotoxicity (CMC) assay. Specific lysis of target cells A20 and EMT-6 primed with EV was demonstrated. The classical CD8+ cytolytic pathway (72.7%) as compared to that of CD4+ (27.3%) in the cellular response during acute infection. Also an alternative method for determining CMC, employing a bis-benzamide dye for labelling target cells, is described. Coefficient variations of relative fluorescence were below 6%, that makes the method sensitive and reliable. Comparison of the assay demonstrated with to that of the 51Cr-release assay is discussed

  2. Cytotoxicity of Silver Nanoparticles in Human Embryonic Stem Cell-Derived Fibroblasts and an L-929 Cell Line

    Directory of Open Access Journals (Sweden)

    Hui Peng

    2012-01-01

    Full Text Available Consensus about the toxicity of silver nanoparticles (Ag-NPs has not been reached, even though extensive attention has been paid to this issue. This confusion may be due to physicochemical factors of Ag-NPs and the cell model used for biological safety evaluation. In the present study, human embryonic stem cell-derived fibroblasts (EBFs, which have been considered a closer representative of the in vivo response, were used as a novel cell model to assess the cytotoxicity of Ag-NPs (~20 nm and ~100 nm in comparison with L-929 fibroblast cell line. Cell proliferation, cell cycle, apoptosis, p53 expression, and cellular uptake were examined. Results showed that Ag-NPs presented higher cytotoxicity to EBF than to L-929. EBF demonstrated a stronger capacity to ingest Ag-NPs, a higher G2/M arrest, and more upgraduated p53 expression after exposed to Ag-NPs for 48 h when compared with L-929. It could be concluded that EBF exhibited a more sensitive response to Ag-NPs compared with L-929 cells, indicating that EBF may be a valid candidate for cytotoxicity screening assays of nanoparticles.

  3. Do cancer cells in human and meristematic cells in plant exhibit similar responses toward plant extracts with cytotoxic activities?

    Science.gov (United States)

    Khalifa, Noha S; Barakat, Hoda S; Elhallouty, Salwa; Salem, Dina

    2015-01-01

    We examined the effect of water extracts of Persea americana fruit, and of the leaves of Tabernamontana divericata, Nerium oleander and Annona cherimolia (positive control) on Vicia faba root cells. We had confirmed in our previously published data the cytotoxicity of these plant extracts on four human cancer cell lines: liver (HepG-2), lung (A549), colon (HT-29) and breast (MCF-7). Vicia faba roots were soaked in plant extracts at dilutions of 100, 1,250, 2,500, 5,000, 10,000, 20,000 ppm for 4 and 24 h. All treatments resulted in a significant reduction in the mitotic index in a dose dependant manner. Root cells treated with T. divericata, N. oleander and A. cherimolia exhibited a decrease in prophase cell percentage, increase in micronuclei and chromosomal abnormalities as concentration increased. The P. americana treatment showed the highest cytotoxic effect on cancer cells, prophase cell percentage increased linearly with the applied concentration and no micronuclei were detected. This study shows that root tip assay of beans can be used in initial screening for new plant extracts to validate their use as candidates for containing active cytotoxic agents against malignant cells. This will greatly help in exploring new plant extracts as drugs for cancer treatment. PMID:24705601

  4. DNA fragmentation and cytotoxicity by recombinant human tumor necrosis factor in L929 fibroblast cells

    International Nuclear Information System (INIS)

    Induction of cell DNA fragmentation by treatment of recombinant human Tumor Necrosis Factor alpha (rhTNF alpha) was examined by using mouse L929 cells derived from mouse fibroblast cells. The amount of DNA fragments derived from rhTNF alpha-treated cells, detected by alkaline elution technique, was smaller than that derived from X-irradiated cells. The rhTNF alpha caused the DNA fragmentation depending on its incubation time and concentration. The DNA damage caused by rhTNF alpha treatment correlated with its cytotoxicity. This result suggested that the DNA fragmentation is one of causes of cell death. The treatment with proteinase K of DNA obtained from rhTNF alpha-treated cells did not increase the amount of DNA fragmentation, which indicates that rhTNF alpha causes DNA-fragmentation but not DNA-protein cross-linking

  5. Electroporation enhances mitomycin C cytotoxicity on T24 bladder cancer cell line

    DEFF Research Database (Denmark)

    Vasquez, Juan Luis; Gehl, Julie; Hermann, Gregers G

    2012-01-01

    Intravesical mitomycin instillation combined with electric pulses is being used experimentally for the treatment of T1 bladder tumors, in patients unfit for surgery. Electroporation may enhance the uptake of chemotherapeutics by permeabilization of cell membranes. We investigated if electroporation...... improves the cytotoxicity of mitomycin. In two cell lines, T24 (bladder cancer cell line) and DC3F (Chinese hamster fibroblast), exposure to different concentrations of mitomycin (0.01-2000μM) was tested with and without electroporation (6 pulses of 1kV/cm, duration: 99μs, frequency: 1Hz). Cell viability...... was assessed by colorimetric assay (MTT). For both cell lines, mitomycin's IC_50 was approximately 1000μM in both pulsed and unpulsed cells. On T24 cells, electroporation and mitomycin caused (relative reduction) RR of survival of: 25%, 31% and 29%, by concentrations 0μM, 500μM and 1000μM respectively...

  6. In vitro Cytotoxicity of TCDD on SPC-A1 Cells

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective The toxicology of TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) has been studied mainly with regard to the carcinogenicity of its metabolites, but its phototoxicity is not well understood. Although some studies have indicated the lethal phototoxicity of TCDD, this study was designed to investigate its effect on SPC-A1 cells. Methods SPC-A1 cells were cultured in 1640 medium and treated with 10 nmol/L, 0.1 μmol/L, 1 μmol/L TCDD for either 24 h or 96 h at each concentration. SPC-A1 cells were co-cultured with TCDD at different concentrations. Then the cell morphology, DNA fragment electrophoresis, and cell cycle were analyzed by flow cytometry, and enzyme assays were used to observe the effect of TCDDon the morphology, growth rate, and enxyme change of SPC-A1 cells. Results With the increasing concentrations of TCDD and prolongation of culture time, the morphology of SPC-A1 cells was changed from round shape to spindle, and the ability of SPC-A1 cells to adhere to wall was decreased. With debris emitted around the cells, the morphologic changes included reduction in cell volume. Nuclear chromatin condensation and PI were observed. With the increasing concentrations of TCDD,DNA ladder occurred. After treatment with TCDD, extraction of cancer cells exhibited typical DNA fragmentation, and flow cytometry analysis showed apoptosis in a dose-dependent manner. As the concentration of TCDD rose from 10 nmol/L to 1 μmol/L, the ratio of apoptotic cells increased from 10.76% to 21.82%. Conclusions TCDD has in vitro cytotoxicity on SPC-A1 cells, and the cytotoxicity is positively related to its concentration and culture time. TCDD may inhibit the growth and proliferation of SPC-A 1 cells through the pathway of apoptosis introduction.

  7. Engineering antigen-specific T cells from genetically modified human hematopoietic stem cells in immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Scott G Kitchen

    Full Text Available There is a desperate need for effective therapies to fight chronic viral infections. The immune response is normally fastidious at controlling the majority of viral infections and a therapeutic strategy aimed at reestablishing immune control represents a potentially powerful approach towards treating persistent viral infections. We examined the potential of genetically programming human hematopoietic stem cells to generate mature CD8+ cytotoxic T lymphocytes that express a molecularly cloned, "transgenic" human anti-HIV T cell receptor (TCR. Anti-HIV TCR transduction of human hematopoietic stem cells directed the maturation of a large population of polyfunctional, HIV-specific CD8+ cells capable of recognizing and killing viral antigen-presenting cells. Thus, through this proof-of-concept we propose that genetic engineering of human hematopoietic stem cells will allow the tailoring of effector T cell responses to fight HIV infection or other diseases that are characterized by the loss of immune control.

  8. Cytotoxic and inflammatory responses of TiO2 nanoparticles on human peripheral blood mononuclear cells.

    Science.gov (United States)

    Kongseng, Supunsa; Yoovathaworn, Krongtong; Wongprasert, Kanokpan; Chunhabundit, Rodjana; Sukwong, Patinya; Pissuwan, Dakrong

    2016-10-01

    Titanium dioxide nanoparticles (TiO2 -NPs) have been widely used in many applications. Owing to their nanoscale size, interactions between cells and NPs have been expansively investigated. With the health concerns raised regarding the adverse effects of these interactions, closer examination of whether TiO2 -NPs can induce toxicity towards human cells is greatly needed. Therefore, in this study, we investigated the cytotoxicity of TiO2 -NPs towards human blood cells (peripheral blood mononuclear cells [PBMCs]) in serum-free medium, for which there is little information regarding the cytotoxic effects of TiO2 -NPs. Our results provide evidence that PBMCs treated with TiO2 -NPs (at concentrations ≥25 μg ml(-1) ) for 24 h significantly reduced cell viability and significantly increased production of toxic mediators such as reactive oxygen species and inflammatory response cytokines such as interleukin-6 and tumor necrosis factor-α (P < 0.05). Cell apoptosis induction also occurred at these concentrations. Significant expressions of cyclooxygenase-2 and interleukin-1β were also observed in PBMCs treated with TiO2 -NPs at concentrations ≥125 μg ml(-1) . Our data presented here clearly indicate that the concentration of TiO2 -NPs (at size ~26.4 ± 1.2 nm) applied to human blood cells has a strong impact on cytotoxic induction. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27225715

  9. Schedule-Dependent Antiangiogenic and Cytotoxic Effects of Chemotherapy on Vascular Endothelial and Retinoblastoma Cells.

    Science.gov (United States)

    Winter, Ursula; Mena, Hebe A; Negrotto, Soledad; Arana, Eloisa; Pascual-Pasto, Guillem; Laurent, Viviana; Suñol, Mariona; Chantada, Guillermo L; Carcaboso, Angel M; Schaiquevich, Paula

    2016-01-01

    Current treatment of retinoblastoma involves using the maximum dose of chemotherapy that induces tumor control and is tolerated by patients. The impact of dose and schedule on the cytotoxicity of chemotherapy has not been studied. Our aim was to gain insight into the cytotoxic and antiangiogenic effect of the treatment scheme of chemotherapy used in retinoblastoma by means of different in vitro models and to evaluate potential effects on multi-drug resistance proteins. Two commercial and two patient-derived retinoblastoma cell types and two human vascular endothelial cell types were exposed to increasing concentrations of melphalan or topotecan in a conventional (single exposure) or metronomic (7-day continuous exposure) treatment scheme. The concentration of chemotherapy causing a 50% decrease in cell proliferation (IC50) was determined by MTT and induction of apoptosis was evaluated by flow cytometry. Expression of ABCB1, ABCG2 and ABCC1 after conventional or metronomic treatments was assessed by RT-qPCR. We also evaluated the in vivo response to conventional (0.6 mg/kg once a week for 2 weeks) and metronomic (5 days a week for 2 weeks) topotecan in a retinoblastoma xenograft model. Melphalan and topotecan were cytotoxic to both retinoblastoma and endothelial cells after conventional and metronomic treatments. A significant decrease in the IC50 (median, 13-fold; range: 3-23) was observed following metronomic chemotherapy treatment in retinoblastoma and endothelial cell types compared to conventional treatment (p0.05). In mice, continuous topotecan lead to significantly lower tumor volumes compared to conventional treatment after 14 days of treatment (pretinoblastoma and endothelial cells to both chemotherapy agents with lower IC50 values compared to short-term treatment. These findings were validated in an in vivo model. None of the dosing modalities induced multidrug resistance mechanisms while apoptosis was the mechanism of cell death after both treatment

  10. Cytotoxicity of Human Cord Blood Natural Killer Cells is Enhanced by Recombinant Interleukin-15

    Directory of Open Access Journals (Sweden)

    Shiva Saghafi

    2010-06-01

    Full Text Available Hematopoietic cord blood (CB stem cell transplantation has more advantages to other cell sources because of lower Graft Versus Host Disease (GVHD. Interleukin-15(IL-15 is an immunoregulatory cytokine, known to enhance cytolytic function of cord Natural Killer (NK cells. The aim of this study was to investigate the effect of IL-15 on NK cytotoxicity simultaneously in different cell death stages.We compared the ability of IL-15 to enhance the NK cytotoxicity of CB in comparison to adult blood Mononuclear Cells (MNCs against K562 target cells by co-staining with AnnexinV-FITC and Propidium Iodide after 3.5 h incubation at 37C and 5% CO2 by using flow cytometric method. We also evaluated phenotypic changes after treatment by IL-15 in both cell sources.Our results indicated that CB samples had lower level of apoptosis, while necrosis was negligible; also by escalating Effector: Target (E: T, we got higher level of apoptosis and necrosis in peripheral blood (PB. NK activity of cord and adult MNCs was enhanced by incubation with IL-15 (10 ng/ml for 72 h with significantly higher results of PB in comparison to CB (pTaken together, these results indicated that NK cytotoxicity of CB MNCs could be augmented by human recombinant (hr IL-15, but this activity did not reach to same level of PB counterparts.We established that CD25 expression on CB MNCs could be increased with IL-15, in 72-hour cultures, but to a lesser degree compared to that on corresponding adult PB MNCs.

  11. Primary stimulation by dendritic cells induces antiviral proliferative and cytotoxic T cell responses in vitro

    OpenAIRE

    1989-01-01

    We used well-gassed hanging drop (20 microliters) cultures with high concentrations of purified T cells from normal BALB/c mice to examine whether dendritic cells (DC) can induce primary antiviral proliferative T cell responses and generate virus-specific CTL. We found that DC exposed to infectious influenza virus in vitro or in vivo in small numbers (0.1-1%) resulted in strong proliferation of responder T cells within 3 d, and this was strongly inhibited by antibodies to class II MHC molecul...

  12. Decreased Cytotoxicity of Peripheral and Peritoneal Natural Killer Cell in Endometriosis

    Science.gov (United States)

    Jeung, InCheul; Cheon, Keunyoung; Kim, Mee-Ran

    2016-01-01

    Endometriosis causes significant chronic pelvic pain, dysmenorrhea, and infertility and affects 10% of all women. In endometriosis, ectopic endometrium surviving after retrograde menstruation exhibits an abnormal immune response characterized by increased levels of activated macrophages and inflammatory cytokines. Particularly, dysfunctional natural killer (NK) cells play an important role in the pathogenesis of the disease by either facilitating or inhibiting the survival, implantation, and proliferation of endometrial cells. NK cells in the peritoneum and peritoneal fluid exhibit reduced levels of cytotoxicity in women with endometriosis. Several cytokines and inhibitory factors in the serum and peritoneal fluid also dysregulate NK cell cytotoxicity. Additionally, increased numbers of immature peripheral NK cells and induction of NK cell apoptosis are evident in the peritoneal fluid of women with endometriosis. The high rate of endometriosis recurrence after pharmaceutical or surgical treatment, which is associated with dysfunctional NK cells, indicates that new immunomodulatory management strategies are required. A good understanding of immune dysfunction would enable improvement of current treatments for endometriosis. PMID:27294113

  13. Synchrotron infrared spectromicroscopy as a novel bioanalytical microprobe for individual living cells: Cytotoxicity considerations

    Energy Technology Data Exchange (ETDEWEB)

    Holman, Hoi-Ying N.; Bjornstad, Kathleen A.; McNamara, Morgan P.; Martin, Michael C.; McKinney, Wayne R.; Blakely, Eleanor A.

    2001-12-12

    Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging analytical tool capable of monitoring the biochemistry within an individual living mammalian cell in real time. This unique technique provides infrared (IR)spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Mid-IR photons are too low in energy (0.05-0.5 eV) to either break bonds or to cause ionization, and the synchrotron IR beam has been shown to produce minimal sample heating. However, an important question remains, ''Does the intense synchrotron beam induce any cytotoxic effects in living cells?'' In this work, we present the results from a series of standard biological assays to evaluate any short-and/or long-term effects on cells exposed to the synchrotron radiation-based infrared (SR-IR) beam. Cell viability was tested using alcian blue dye-exclusion and colony formation assays. Cell-cycle progression was tested with bromodeoxyuridine (BrdU) uptake during DNA synthesis. Cell metabolism was tested using an 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. All control, 5-, 10-, and 20-minute SR-IR exposure tests (267 total and over 1000 controls) show no evidence of cytotoxic effects. Concurrent infrared spectra obtained with each experiment confirm no detectable chemistry changes between control and exposed cells.

  14. Cytotoxicity of some oxysterols on human vascular smooth muscle cells was mediated by apoptosis.

    Science.gov (United States)

    Miyashita, Y; Shirai, K; Ito, Y; Watanabe, J; Urano, Y; Murano, T; Tomioka, H

    1997-01-01

    A decrease in smooth muscle cells is observed in advanced atherosclerotic lesion. To understand this mechanism, we selected oxysterols as candidates for toxic lipid, and examined their cytotoxicity on human cultured vascular smooth muscle cells, together with the manner of cell death. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol (50 mumol/L), the percentage of detached cells increased significantly with dose dependency, and an increase in detached cell number and DNA nick detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling study (TUNEL) preceded an increase in lactate dehydrogenase released into the medium. DNA extracted from smooth muscle cells incubated with 7-ketocholesterol or 7 beta-hydroxycholesterol showed a laddering pattern on agarose electrophoresis. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol, fragmented DNA quantified by the quantitative sandwich enzyme immunoassay was significantly increased. From these results, it is proposed that 7-ketocholesterol and 7 beta-hydroxycholesterol are toxic to smooth muscle cells, and that this cytotoxicity is mediated by apoptosis. PMID:9638517

  15. Primary central nervous system gamma delta cytotoxic T-cell lymphoma.

    Science.gov (United States)

    Mooney, Kelly L; Choy, Winward; Woodard, Joslyn; Xian, Rena R; Deal, Taylor M; Kendle, Ryan F; Said, Jonathan; Grody, Wayne; Yang, Isaac

    2016-04-01

    Primary T-cell lymphomas of the central nervous system (CNS) are uncommon, but aggressive and increasing in incidence. We describe a rare case of T-cell lymphoma in a cerebellar location, to our knowledge the first reported case demonstrating gamma/delta receptor expression. Additionally, we elaborate on key diagnostic features and review all nine patients with primary CNS lymphoma of cytotoxic T-cell phenotype reported in the literature. A 26-year-old female medical student presented with a 6week history of nausea, vomiting and dizziness. MRI revealed a 2cm cerebellar mass. The tumor was subtotally resected, and pathologic examination of a subtotal resection specimen demonstrated peripheral T-cell lymphoma, not otherwise specified, with a gamma/delta cytotoxic T-cell phenotype. She subsequently started high dose methotrexate and cytarabine. We report a unique case of primary CNS gamma delta CD8+ T-cell lymphoma lineage in a young female patient. While these are rare entities, it is an important differential diagnosis to consider. Therapy should be tailored to the patient, and involves resection with adjuvant chemotherapy, radiotherapy or autologous stem-cell based treatments. PMID:26804925

  16. Polyphenols of Mangifera indica modulate arsenite-induced cytotoxicity in a human proximal tubule cell line

    Directory of Open Access Journals (Sweden)

    Gabino Garrido

    2012-04-01

    Full Text Available Inorganic arsenic is an ubiquitous environmental contaminant able to cause severe pathologies in humans, including kidney disorders. The possible protective effects of Mangifera indica L., Anacardiaceae, stem bark extract (MSBE and some mango phenols on the cytotoxicity of arsenite (AsIII in the proximal tubule cell line HK-2 was investigated. In cells cultured for 24 h in presence of AsIII, a dose-dependent loss of cell viability occurred that was significantly alleviated by MSBE, followed by gallic acid, catechin and mangiferin. Mangiferin complexed with Fe+++ proved more efficacious than mangiferin alone. MSBE and pure phenols increased significantly the cell surviving fraction in clonogenic assays. In cells pretreated with MSBE or phenols for 72 h the protection afforded by MSBE resulted decreased in comparison with the shorter experiments. Cells pretreated with a subcytotoxic amount of AsIII or cultured in continuous presence of low concentration of mangiferin proved to be more resistant to AsIII, while cells cultured in presence of albumin resulted more sensitive. Because all the above conditions share changes in expression/activity of P-glycoprotein (P-gp, a transporter potentially involved in arsenic resistance, the capability of M. indica phenols in modulating AsIII-induced cytotoxicity would be at least in part dependent on their interactions with P-gp.

  17. Radioimmunotherapy: A Specific Treatment Protocol for Cancer by Cytotoxic Radioisotopes Conjugated to Antibodies

    Directory of Open Access Journals (Sweden)

    Hidekazu Kawashima

    2014-01-01

    Full Text Available Radioimmunotherapy (RIT represents a selective internal radiation therapy, that is, the use of radionuclides conjugated to tumor-directed monoclonal antibodies (including those fragments or peptides. In a clinical field, two successful examples of this treatment protocol are currently extended by 90Y-ibritumomab tiuxetan (Zevalin and 131I-tositumomab (Bexxar, both of which are anti-CD20 monoclonal antibodies coupled to cytotoxic radioisotopes and are approved for the treatment of non-Hodgkin lymphoma patients. In addition, some beneficial observations are obtained in preclinical studies targeting solid tumors. To date, in order to reduce the unnecessary exposure and to enhance the therapeutic efficacy, various biological, chemical, and treatment procedural improvements have been investigated in RIT. This review outlines the fundamentals of RIT and current knowledge of the preclinical/clinical trials for cancer treatment.

  18. In vitro cytotoxic effects of CTL activated by dendritic cells loaded with esophageal cancer antigen peptide by 51Cr release assay

    International Nuclear Information System (INIS)

    Objective: RIT plays an important role in the targeted therapy for tumors. The aim of the paper was to study cytotoxic effects of the cytotoxic T lymphocytes (CTL) to human esophageal cancer cell line TE-1, activated by dendritic cells (DC) loaded with esophageal cancer antigen peptide. Methods: Esophageal cancer TE-1 cell antigen peptide was obtained by citrate phosphate buffer elution. DC were induced and proliferated in vitro and were loaded with the esophageal cancer antigen peptide. The tumor antigen specific CTL were generated from the DC. And the cytotoxicity of CTL to TE-1 was assessed by 51Cr release assay. Results: The killing rate of CTL activated by loaded DC[(81.12±2.93)%] was higher than that of CTL activated by DC unloaded [(11.16±3.07)%]. The killing rate of CTL activated by loaded DC in TE-1 pretreated with interferon (IFN)-γ [(89.15±3.62)%] was higher than that in cells without IFN-γ [(61.19±5.17)%]. The killing rate of CTL was higher than that in TE-1 with acid elution [(9.18±2.52)%]. The killing rate of CTL activated by loaded DC diminished in order in Eta-109, human adenocarcinoma cell line K59 and human suprarenal epithelioma cell line 786-0. Conclusions: Acid elution could get effective esophageal cancer antigen peptide from TE-1 cell membrane. The CTL activated by DC loaded with that peptide had specific cytotoxic effects to TE-1 cells. (authors)

  19. The Natural Killer Cell Cytotoxic Function Is Modulated by HIV-1 Accessory Proteins

    Directory of Open Access Journals (Sweden)

    Edward Barker

    2011-07-01

    Full Text Available Natural killer (NK cells’ major role in the control of viruses is to eliminate established infected cells. The capacity of NK cells to kill virus-infected cells is dependent on the interactions between ligands on the infected cell and receptors on the NK cell surface. Because of the importance of ligand-receptor interactions in modulating the NK cell cytotoxic response, HIV has developed strategies to regulate various NK cell ligands making the infected cell surprisingly refractory to NK cell lysis. This is perplexing because the HIV-1 accessory protein Vpr induces expression of ligands for the NK cell activating receptor, NKG2D. In addition, the accessory protein Nef removes the inhibitory ligands HLA-A and -B. The reason for the ineffective killing by NK cells despite the strong potential to eliminate infected cells is due to HIV-1 Vpu’s ability to down modulate the co-activation ligand, NTB-A, from the cell surface. Down modulation of NTB-A prevents efficient NK cell degranulation. This review will focus on the mechanisms through which the HIV-1 accessory proteins modulate their respective ligands, and its implication for NK cell killing of HIV-infected cells.

  20. Complement-dependent cytotoxicity of antibodies reactive with HIV-induced cell surface antigens in HIV-carrying haemophiliacs

    International Nuclear Information System (INIS)

    Sera obtained from HIV positive and from uninfected hemophiliacs and from healthy subjects were investigated for the presence of lymphocytotoxic antibodies. Using the 51Cr-release test, HIV-positive hemophiliacs were found to produce serum antibodies exerting a complement-dependent cytotoxic effect on HIV-infected T4 cells. The antibodies were reactive mainly when HIV-infected target cells were stimulated with concanavalin A. The results of complement-dependent antibody cytotoxicity and indirect membrane immunofluorescence tests suggest that envelope antigen(s) of HIV may be the target(s) for cytotoxic antibodies. (author)

  1. Cytotoxicity of Elaoephorbia drupifera and other Cameroonian medicinal plants against drug sensitive and multidrug resistant cancer cells

    OpenAIRE

    Kuete, Victor; Voukeng, Igor K; Tsobou, Roger; Mbaveng, Armelle T; Wiench, Benjamin; Beng, Veronique P; Efferth, Thomas

    2013-01-01

    Background Multidrug resistance (MDR) is a major hurdle for cancer treatment worldwide and accounts for chemotherapy failure in over 90% of patients with metastatic cancer. Evidence of the cytotoxicity of Cameroonian plants against cancer cell lines including MDR phenotypes is been intensively and progressively provided. The present work was therefore designed to evaluate the cytotoxicity of the methanol extracts of twenty-two Cameroonian medicinal plants against sensitive and MDR cancer cell...

  2. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

    Science.gov (United States)

    Putz, Eva Maria; Gotthardt, Dagmar; Hoermann, Gregor; Csiszar, Agnes; Wirth, Silvia; Berger, Angelika; Straka, Elisabeth; Rigler, Doris; Wallner, Barbara; Jamieson, Amanda M.; Pickl, Winfried F.; Zebedin-Brandl, Eva Maria; Müller, Mathias; Decker, Thomas; Sexl, Veronika

    2013-01-01

    Summary The transcription factor STAT1 is important in natural killer (NK) cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A) enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8). Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance. PMID:23933255

  3. Characterization of crude Echis carinatus venom-induced cytotoxicity in HEK 293T cells.

    Science.gov (United States)

    Pierce, Rebecca D; Kim, Ethan S; Girton, Lance W; McMurry, Jonathan L; Francis, Joshua W; Albrecht, Eric A

    2011-01-01

    Echis carinatus (saw-scaled viper) produces potent hemorrhagic venom that causes the development of apoptotic and necrotic tissues. In this study, we used polyethyleneimine (PEI) to enhance cellular adherence, and to determine whether the substrate attachment influenced the survival of cells treated with crude E. carinatus venom. Human embryonic kidney (HEK) 293T cells were grown for 18hr in tissue culture plates with or without polyethyleneimine (PEI), and were then stimulated with crude E. carinatus venom for 3 or 12hr. HEK 293T cells grown without PEI displayed a robust oxidative response to corresponding substrate detachment, loss of plasma membrane integrity and decreased cell viability. Cells grown on PEI adsorbed substrates demonstrated prolonged substrate attachment resulting in significantly higher cell viabilities. These observations suggest that the cytotoxicity of crude E. carinatus venom is dependent upon cellular detachment. PMID:22331993

  4. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

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    Eva Maria Putz

    2013-08-01

    Full Text Available The transcription factor STAT1 is important in natural killer (NK cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8. Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance.

  5. Phototoxicity and cytotoxicity of fullerol in human retinal pigment epithelial cells

    International Nuclear Information System (INIS)

    The water-soluble nanoparticle hydroxylated fullerene [fullerol, nano-C60(OH)22-26] has several clinical applications including use as a drug carrier to bypass the blood ocular barriers. We have previously found that fullerol is both cytotoxic and phototoxic to human lens epithelial cells (HLE B-3) and that the endogenous antioxidant lutein blocked some of this phototoxicity. In the present study we have found that fullerol induces cytotoxic and phototoxic damage to human retinal pigment epithelial cells. Accumulation of nano-C60(OH)22-26 in the cells was confirmed spectrophotometrically at 405 nm, and cell viability, cell metabolism and membrane permeability were estimated using trypan blue, MTS and LDH assays, respectively. Fullerol was cytotoxic toward hRPE cells maintained in the dark at concentrations higher than 10 μM. Exposure to an 8.5 J.cm-2 dose of visible light in the presence of > 5 μM fullerol induced TBARS formation and early apoptosis, indicating phototoxic damage in the form of lipid peroxidation. Pretreatment with 10 and 20 μM lutein offered some protection against fullerol photodamage. Using time resolved photophysical techniques, we have now confirmed that fullerol produces singlet oxygen with a quantum yield of Φ = 0.05 in D2O and with a range of 0.002-0.139 in various solvents. As our previous studies have shown that fullerol also produces superoxide in the presence of light, retinal phototoxic damage may occur through both type I (free radical) and type II (singlet oxygen) mechanisms. In conclusion, ocular exposure to fullerol, particularly in the presence of sunlight, may lead to retinal damage.

  6. Immunostimulatory DNA-based vaccines induce cytotoxic lymphocyte activity by a T-helper cell-independent mechanism.

    Science.gov (United States)

    Cho, H J; Takabayashi, K; Cheng, P M; Nguyen, M D; Corr, M; Tuck, S; Raz, E

    2000-05-01

    Immunostimulatory DNA sequences (ISS) contain unmethylated CpG dinucleotides within a defined motif. Immunization with ISS-based vaccines has been shown to induce high antigen-specific cytotoxic lymphocyte (CTL) activity and a Th1-biased immune response. We have developed a novel ISS-based vaccine composed of ovalbumin (OVA) chemically conjugated to ISS-oligodeoxynucleotide (ODN). Protein-ISS conjugate (PIC) is more potent in priming CTL activity and Th1-biased immunity than other ISS-based vaccines. Cytotoxic lymphocyte activation by ISS-ODN-based vaccines is preserved in both CD4-/- and MHC class II-/- gene-deficient animals. Furthermore, PIC provides protection against a lethal burden of OVA-expressing tumor cells in a CD8+ cell-dependent manner. These results demonstrate that PIC acts through two unique mechanisms: T-helper-independent activation of CTL and facilitation of exogenous antigen presentation on MHC class I. This technology may have clinical applications in cancer therapy and in stimulating host defense in AIDS and chronic immunosuppression. PMID:10802617

  7. In Vitro Cytotoxic Effects of Cuscuta chinensis Whole Extract on Human Acute Lymphoblastic Leukemia Cell Line

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    Fatemeh Zeraati

    2010-12-01

    Full Text Available Background: One of the major paths for drug development isthe study of bioactivities of natural products. Therefore, theaim of this study was to compare the cytotoxic effects ofaqueous extract of whole Cuscuta chinensis Lam., which is atraditional medicinal herb commonly used in Iran and otheroriental countries, on the human caucasian acute lymphoblasticleukemia (CCRF-CEM and another human lymphocyte,Jurkat (JM cell lines.Methods: In vitro cytotoxic screening with various concentrations(0, 0.1, 1, 10, 25 and 50 μg/ml of the extract wasperformed using microscope and methyl tetrazolium bromidetest (MTT.Results: The minimum effective concentration of the plantextract was 1 μg/ml, and increasing the dose to 10 μg/mlinduced increasingly stronger effects. The inhibitory concentration50% (IC50 of the extract against CCRF wasabout 3 μg/ml in 24 hours and 2.5 μg/ml in 48 hrs. In contrast,the extract did not have cytotoxic effect for the JMcells at these doses.Conclusion: The findings of the present study suggest that C.chinensis is toxic against CCRF-CEM and JM tumor cells.Whether or not such effects can be employed for the treatmentof such tumors must await future studies.Iran J Med Sci 2010; 35(4: 310-314.

  8. Simultaneous measurement of natural killer cell cytotoxicity against each of three different target cell lines.

    Science.gov (United States)

    Blomberg, K

    1994-02-10

    A time-resolved fluorometric assay for the simultaneous measurement of natural killer cell activity against three different lanthanide diethylenetriaminopentaacetate (LaDTPA) labelled target cell lines is described. The target cell line K-562 was labelled with SmDTPA, the cell line Molt with TbDTPA and the cell line Raji with EuDTPA. After co-incubation of the three target cell lines with effector cells the fluorescence of the lanthanides released from the lysed target cells was measured in an enhancer solution in which they formed highly fluorescent complexes. It was possible to differentiate the specific release from the three target cell lines because the emission lines of the europium, samarium and terbium complexes formed in the enhancer solution are well separated from each other. The autofluorescence from culture media supplemented with serum was avoided by the use of time-resolved fluorometry. The results show that applying fluorometry based on the combination of spectral and temporal resolution to natural killer cell assays, makes possible the simultaneous determination of lysis in up to three target cell lines in complex culture medium. PMID:8308301

  9. Secondary specific immune response in vitro to MSV tumor cells.

    Science.gov (United States)

    Senik, A; Hebrero, F P; Levy, J P

    1975-12-15

    The interactions which occur between antigenic tumor cells and normal or immune lymphoid cells in a 3-day in vitro culture, have been studied with a murine sarcoma virus (MSV)-induced tumor. The 3H-thymidine incorporation of lymphoma cells growing in suspension, and the radioactive-chromium release of freshly sampled lymphoma cells regularly added to the culture, have been compared to determine the part played by immune lymphoid cells in cytolysis and cytostasis of the tumor-cell population. The cytolytic activity increases in the culture from day 0 to day 3. It is due, predominantly, to T-cells, and remains specific to antigens shared by MSV tumors and related lymphomas. This activity would be difficult to detect unless freshly sampled ascitic cells were used as targets, since the lymphoma cells spontaneously lose a part of their sensitivity to immune cytolysis during in vitro culture. The method used in the present experiments is a secondary chromium release test (SCRT), which measures the invitro secondary stimulation of cytotoxic T-lymphocytes (CTL) by tumor cells. In the absence of stimulatory cells, the CTL activity would have rapidly fallen in vitro. The cytostatic activity also increases during the 3 days in vitro, in parallel to the cytolytic activity: it is due to non-T-cells and remains mainly non-specific. The significance of these data for the interpretation of invitro demonstrated cell-mediated anti-tumor immune reactions is briefly discussed, as well as their relevance in the in vivo role of immune CTL. PMID:53210

  10. Cytotoxic effect of Eucalyptus citriodora resin on human hepatoma HepG2 cells.

    Science.gov (United States)

    Shen, Kun-Hung; Chen, Zong-Tsi; Duh, Pin-Der

    2012-01-01

    The aim of this study was to evaluate the antiproliferative effect of Eucalyptus citriodora resin (ECR) on human hepatoma HepG2 cells. The results from MTT assay and LDH leakage analysis showed that water extracts of ECR (WEECR) in the dose range of 0-500 μg/ml displayed stronger cytotoxic effects on HepG2 cells than other organic solvent extracts of ECR. By flow cytometry analysis, WEECR slowed down the cell cycle at the G0/G1 phase after 24 h of incubation. Moreover, WEECR treatment induced an apoptotic response in HepG2 cells. WEECR-induced apoptosis was in association with the attenuation of mitochondrial transmembrane potentials (ΔΨ(m)), increased Bax/Bcl-2 ratio and activation of caspase-3. In addition, WEECR contained high concentration of phenolics and flavonoids, which may be responsible for the potent cytotoxicity of WEECR on HepG2 cells. Taken together, WEECR may be a potent antihepatoma agent due to apoptosis in HepG2 cells. PMID:22419432

  11. Houttuynia cordata Thunb extract induces cytotoxicity in human nasopharyngeal carcinoma cells: Raman spectroscopic studies

    Science.gov (United States)

    Chen, Weiwei; Li, Zuanfang; Yu, Yun; Lin, Duo; Huang, Hao; Shi, Hong

    2016-01-01

    The molecular mechanisms of cytotoxicity induced by Houttuynia cordata Thunb (HCT) in nasopharyngeal carcinoma (NPC) cells was investigated by Raman spectroscopy (RS). The average Raman spectra of cell groups treated with HCT (0, 62.5, 125, 250, and 500 μg ml-1) for 24 h were measured separately. Compared to the control group, the intensities of the selected bands (1002, 1338, and 1448 cm-1) related to protein, DNA, and lipid in the treatment groups decreased obviously as the concentration of HCT increased. Both cell groups treated with 250 and 500 μg ml-1 of HCT could be differentiated from the control group by principal component analysis (PCA) combined with linear discriminate analysis (LDA) with a diagnostic accuracy of 100%, suggesting that cytotoxicity occurred and that 250 μg ml-1 was the proper dose for treatment. Simultaneously, the Raman spectra of cells treated with different treatment times with 250 μg ml-1 of HCT were obtained. We can get that treatment with HCT decreased cell viability in a dose and time-dependent fashion. The results indicated that the RS combined with PCA-LDA can be used for pharmacokinetics studies of HCT in NPC cells, which could also provide useful data for clinical dosage optimization for HCT.

  12. Short communication: selective cytotoxicity of curcumin on osteosarcoma cells compared to healthy osteoblasts

    Directory of Open Access Journals (Sweden)

    Chang R

    2014-01-01

    Full Text Available Run Chang,1 Linlin Sun,1 Thomas J Webster1,21Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 2Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi ArabiaAbstract: Curcumin is a natural phenolic compound extracted from the plant Curcuma longa L. In previous studies, curcumin has been shown to have anticancer, antioxidant, and anti-inflammatory effects. In this study, the cytotoxicity of different concentrations (5, 10, 25, 50, 75, and 100 µM of curcumin dissolved in dimethyl sulfoxide was compared between MG-63 osteosarcoma and healthy human osteoblast cells. Consequently, the viability of osteosarcoma cells was less than 50% at a concentration of 10 µM compared to the control sample without curcumin, but healthy osteoblast cells had at least 80% viability throughout all the concentrations tested. The results demonstrated that MG-63 osteosarcoma cells were much more sensitive in terms of cytotoxicity to curcumin, while the healthy human osteoblasts exhibited a higher healthy viability after 24 hours of curcumin treatment. Therefore, this study showed that at the right concentrations (5 µM to 25 µM, curcumin, along with a proper nanoparticle drug delivery carrier, may selectively kill bone cancer cells over healthy bone cells.Keywords: curcumin, osteosarcoma, human osteoblast, viability, bone cancer

  13. Oxidative stress-mediated cytotoxicity of zirconia nanoparticles on PC12 and N2a cells

    International Nuclear Information System (INIS)

    In recent years, there is a growing interest in the application of nanoparticles like zirconium dioxide (zirconia <100 nm), for many purposes. Since a comprehensive study on the toxic effects of zirconia has not been done, we decided to investigate the effects of zirconia nanoparticles on cultured PC12 and N2a cells. In this study, cytotoxic effect of different concentrations of zirconia nanoparticles at three different time intervals were evaluated using MTT and ROS (reactive oxygen species) assays. Also, Lipid peroxidation, glutathione (GSH) content changes, and DNA damage were measured. Zirconia nanoparticles caused a significant reduction in cell viability and GSH content of the cells, and induce a significant increase in intracellular ROS and MDA content of PC12 and N2a cells. Moreover, it increases the percentage of DNA tail of treated cells as compared with control group. Zirconia nanoparticles have cytotoxic and genotoxic effects in PC12 and N2a cells in a time and concentration-dependent manner in concentration more than 31 µg/mL

  14. Methotrexate-conjugated quantum dots: synthesis, characterisation and cytotoxicity in drug resistant cancer cells.

    Science.gov (United States)

    Johari-Ahar, Mohammad; Barar, Jaleh; Alizadeh, Ali Mohammad; Davaran, Soodabeh; Omidi, Yadollah; Rashidi, Mohammad-Reza

    2016-01-01

    Methotrexate (MTX), a folic acid derivative, is a potent anticancer used for treatment of different malignancies, but possible initiation of drug resistance to MTX by cancer cells has limited its applications. Nanoconjugates (NCs) of MTX to quantum dots (QDs) may favour the cellular uptake via folate receptors (FRs)-mediated endocytosis that circumvents the efflux functions of cancer cells. We synthesised MTX-conjugated l-cysteine capped CdSe QDs (MTX-QD nanoconjugates) and evaluated their internalisation and cytotoxicity in the KB cells with/without resistancy to MTX. The NCs were fully characterised by high resolution transmission electron microscopy (HR-TEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and optical spectroscopy. Upon conjugation with MTX, the photoluminescence (PL) properties of QDs altered, while an obvious quenching in PL of QDs was observed after physical mixing. The MTX-QD nanoconjugates efficiently internalised into the cancer cells, and induced markedly high cytotoxicity (IC50, 12.0 µg/mL) in the MTX-resistant KB cells as compared to the free MTX molecules (IC50,105.0 µg/mL), whereas, these values were respectively about 7.0 and 0.6 µg/mL in the MTX-sensitive KB cells. Based on these findings, the MTX-QD nanoconjugates are proposed for the targeted therapy of MTX-resistant cancers, which may provide an improved outcome in the relapsed FR-overexpressing cancers. PMID:26176269

  15. Oxidative stress-mediated cytotoxicity of zirconia nanoparticles on PC12 and N2a cells

    Energy Technology Data Exchange (ETDEWEB)

    Asadpour, Elham [Shiraz University of Medical Sciences, Anesthesiology and Critical Care Research Center (Iran, Islamic Republic of); Sadeghnia, Hamid R. [Mashhad University of Medical Sciences, Department of Pharmacology, Faculty of Medicine (Iran, Islamic Republic of); Ghorbani, Ahmad [Mashhad University of Medical Sciences, Pharmacological Research Center of Medicinal Plants (Iran, Islamic Republic of); Sedaghat, Mehran, E-mail: m-sedaghat81@yahoo.com [Mashhad University of Medical Sciences, Department of Neurosurgery (Iran, Islamic Republic of); Boroushaki, Mohammad T., E-mail: boroushakimt@mums.ac.ir [Mashhad University of Medical Sciences, Department of Pharmacology, Faculty of Medicine (Iran, Islamic Republic of)

    2016-01-15

    In recent years, there is a growing interest in the application of nanoparticles like zirconium dioxide (zirconia <100 nm), for many purposes. Since a comprehensive study on the toxic effects of zirconia has not been done, we decided to investigate the effects of zirconia nanoparticles on cultured PC12 and N2a cells. In this study, cytotoxic effect of different concentrations of zirconia nanoparticles at three different time intervals were evaluated using MTT and ROS (reactive oxygen species) assays. Also, Lipid peroxidation, glutathione (GSH) content changes, and DNA damage were measured. Zirconia nanoparticles caused a significant reduction in cell viability and GSH content of the cells, and induce a significant increase in intracellular ROS and MDA content of PC12 and N2a cells. Moreover, it increases the percentage of DNA tail of treated cells as compared with control group. Zirconia nanoparticles have cytotoxic and genotoxic effects in PC12 and N2a cells in a time and concentration-dependent manner in concentration more than 31 µg/mL.

  16. Cytotoxic effect of the biotechnologically-derived justicidin B on human lymphoma cells.

    Science.gov (United States)

    Ilieva, Y; Zhelezova, I; Atanasova, T; Zaharieva, M M; Sasheva, P; Ionkova, I; Konstantinov, S

    2014-11-01

    Purpose of work: The study was aimed to assess the antineoplastic activity of justicidin B in vitro and to search for its general toxicological profile in vivo. The anti-neoplastic activity of the arylnaphthalene lignin, justicidin B, was assessed in a panel of human lymphoma cell lines and compared with etoposide as a reference compound. A screening of the cytotoxicity after 24, 48 and 72 h exposure was performed by the MTT-dye reduction assay. Dose- and time-dependent cytotoxic effect was observed and the IC50 values ranged from 0.17 µM (RPMI-8226, 72 h) to 183 µM (U-266, 24 h) and more than 200 µM (HD-MY-Z, 24 and 48 h). Activation of caspase 3 and 8 was involved in the induction of programmed cell death in DOHH-2 cell line. NF-κB modulation occurred in DOHH-2 and HH cells. The general toxicity in mice after i.p. injection was also tested. The highest applied dose (50 mg/kg = 137.25 µM) did not show any toxicity. Justicidin B possesses definite and potent selective antineoplastic activity, related to its ability to induce programmed cell death in NHL-derived human cell lines at concentrations that can be reached in mice without toxicity. PMID:25048236

  17. Rapamycin potentiates cytotoxicity by docetaxel possibly through downregulation of Survivin in lung cancer cells

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    Li Hui

    2011-03-01

    Full Text Available Abstract Background To elucidate whether rapamycin, the inhibitor of mTOR (mammalian target of rapamycin, can potentiate the cytotoxic effect of docetaxel in lung cancer cells and to probe the mechanism underlying such enhancement. Methods Lung cancer cells were treated with docetaxel and rapamycin. The effect on the proliferation of lung cancer cells was evaluated using the MTT method, and cell apoptosis was measured by flow cytometry. Protein expression and level of phosphorylation were assayed using Western Blot method. Results Co-treatment of rapamycin and docetaxel was found to favorably enhance the cytotoxic effect of docetaxel in four lung cancer cell lines. This tumoricidal boost is associated with a reduction in the expression and phosphorylation levels of Survivin and ERK1/2, respectively. Conclusion The combined application of mTOR inhibitor and docetaxel led to a greater degree of cancer cell killing than that by either compound used alone. Therefore, this combination warrants further investigation