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- Baureus Koch, Catrin
(författare)
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Effects of ionising and non-ionising radiation in cell systems and a rat model for immuno-therapy
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The most malignant brain tumour, glioblastoma multiforme (GBM), has an utterly bad prognosis. In spite of all available therapy, the mean survival time is less than a year. In the unique BRIGTT project (Brain Immuno Gene Tumour Therapy), patients at the Dept of Neurosurgery. Lund University Hospital, are immunised with their own glioma cells, which have been transfected with the immunostimulatory Interferon-gamma gene by adenoviral vector technique. The thesis describes the development of the culturing techniques necessary for the BRIGTT project. A 75% success rate in achieving pure malignant cell cultures for treatment has been reached. These cells must not divide after injection intradermally but should survive long enough in the patient to alert the immune system. Therefore they must be irradiated before immunisation of the patient. The appropriate absorbed dose had to be identified and 100 Gy was found to be safe and has been used for all 9 treated patients in the study which has shown significantly prolonged survival in the treated patients, all above 50 years of age, but all have developed recurrences. Thus it is important to seek for other new therapies possible to combine with the immunotherapy. A novel possible method is the use of Pulsed Electric Fields (PEF) for local permeabilisation of cell membranes for release of tumour antigens to alert the immune system. In a rat model with glioma cells inoculated subcutaneously in either one or both thighs, where gliomas develop, we have studied the effect of combined PEF and Radiation Therapy (RT). In the rats with unilateral tumour we have shown complete remissions after repeated combined treatments. Based upon the results in this study, we have also developed a new mathematical model which offers a simple way to evaluate Tumour Growth Rate (TGR) and synergistic effects of combined therapies. As the basis for our clinical therapy is to stimulate the immune system, we continued the work by examining the possible immunological effects of PEF and/or RT in the rat model with bilaterally implanted thigh tumours. By treating only one of them, we could investigate the so called abscopal effect (distant effect) on the other, non-treated tumour. The TGR of the treated tumours was significantly reduced in all the treatment groups and also in the non-treated contralateral tumours in the RT and PEF + RT groups. The conclusion of this is that an abscopal effect is evident and that the possibility to add PEF to immunotherapy protocols such as BRIGTT may an important step in the search for a cure for the malignant gliomas
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| 2. |
- Baureus Koch, Catrin, et al.
(författare)
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Interaction between weak low frequency magnetic fields and cell membranes.
- 2003
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Ingår i: Bioelectromagnetics. - : Wiley. - 0197-8462. ; 24:6, s. 395-402
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Tidskriftsartikel (refereegranskat)abstract
- The question of whether very weak low frequency magnetic fields can affect biological systems, has attracted attention by many research groups for quite some time. Still, today, the theoretical possibility of such an interaction is often questioned and the site of interaction in the cell is unknown. In the present study, the influence of extremely low frequency (ELF) magnetic fields on the transport of Ca2+ was studied in a biological system consisting of highly purified plasma membrane vesicles. We tested two quantum mechanical theoretical models that assume that biologically active ions can be bound to a channel protein and influence the opening state of the channel. Vesicles were exposed for 30 min at 32 °C and the calcium efflux was studied using radioactive 45Ca as a tracer. Static magnetic fields ranging from 27 to 37 T and time varying magnetic fields with frequencies between 7 and 72 Hz and amplitudes between 13 and 114 T (peak) were used. We show that suitable combinations of static and time varying magnetic fields directly interact with the Ca2+ channel protein in the cell membrane, and we could quantitatively confirm the model proposed by Blanchard. Bioelectromagnetics 24:395-402, 2003. © 2003 Wiley-Liss, Inc.
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| 3. |
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| 4. |
- Belyaev, IY, et al.
(författare)
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Exposure of rat brain to 915 MHz GSM microwaves induces changes in gene expression but not double stranded DNA breaks or effects on chromatin conformation
- 2006
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Ingår i: Bioelectromagnetics. - : Wiley. - 0197-8462 .- 1521-186X. ; 27:4, s. 295-306
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Tidskriftsartikel (refereegranskat)abstract
- We investigated whether exposure of rat brain to microwaves (MWs) of global system for mobile communication (GSM) induces DNA breaks, changes in chromatin conformation and in gene expression. An exposure installation was used based on a test mobile phone employing a GSM signal at 915 MHz, all standard modulations included, output power level in pulses 2 W, specific absorption rate (SAR) 0.4 mW/g. Rats were exposed or sham exposed to MWs during 2 h. After exposure, cell suspensions were prepared from brain samples, as well as from spleen and thymus. For analysis of gene expression patterns, total RNA was extracted from cerebellum. Changes in chromatin conformation, which are indicative of stress response and genotoxic effects, were measured by the method of anomalous viscosity time dependencies (AVTD). DNA double strand breaks (DSBs) were analyzed by pulsed-field gel electrophoresis (PFGE). Effects of MW exposure were observed on neither conformation of chromatin nor DNA DSBs. Gene expression profiles were obtained by Affymetrix U34 GeneChips representing 8800 rat genes and analyzed with the Affymetrix Microarray Suite (MAS) 5.0 software. In cerebellum from all exposed animals, I I genes were upregulated in a range of 1.34-2.74 fold and one gene was downregulated 0.48-fold (P <.0025). The induced genes encode proteins with diverse functions including neurotransmitter regulation, blood-brain barrier (BBB), and melatonin production. The data shows that GSM MWs at 915 MHz did not induce PFGE-detectable DNA double stranded breaks or changes in chromatin conformation, but affected expression of genes in rat brain cells. Bioelectromagnetics 27:295-306, 2006. (c) 2006 Wiley-Liss, Inc.
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| 5. |
- Persson, Bertil R, et al.
(författare)
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“Abscopal” Effect of Radiation Therapy Combined with Immune-Therapy Using IFN-γ Gene Transfected Syngeneic Tumor Cells, in Rats with Bilateral Implanted N29 Tumors
- 2011
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Ingår i: ISRN Immunology. - : Hindawi Limited. - 2090-5645 .- 2090-5653. ; 2011
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Tidskriftsartikel (refereegranskat)abstract
- The tumor growth rate response was studied on N29 rat glioma tumor cells subcutaneously implanted on both hind legs of Fischer-344 rats. At around 30 days after inoculation, RT was given with 60Co gamma radiation with 4 daily fractions of 5 Gy only to the right-lateral tumors. At days 26, 42, and 54 after inoculation, immunization was performed with irradiated syngeneic IFNγ-gene transfected cells. Tumor growth rate (TGR % per day) of the right-lateral irradiated tumor was significantly decreased (P<0.01) after RT alone and with the combination of RT and immunization. But immunization alone gave no significant decrease of the TGR but significantly increased time of survival. The TGR of the unirradiated left-lateral tumors was significantly decreased (P<0.02) only in the group of rats treated with RT alone. It is apparent that tumor cells killed by the radiation mediate suppression of tumor cells outside the target area. This effect is called the abscopal effect.
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| 6. |
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| 7. |
- Persson, Bertil R.R., et al.
(författare)
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A Model for Evaluating Therapeutic Response of Combined Cancer Treatment Modalities : Applied to Treatment of Subcutaneously Implanted Brain Tumors (N32 and N29) in Fischer Rats with Pulsed Electric Fields (PEF) and 60Co-gamma Radiation (RT)
- 2003
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Ingår i: Technology in Cancer Research and Treatment. - : SAGE Publications. - 1533-0346 .- 1533-0338. ; 2:5, s. 459-470
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study is to develop a mathematical model for evaluating therapeutic response of combined treatment modalities. The study was performed in rats of the Fischer-344 strain with rat glioma N32 or N29 tumors implanted subcutaneously on the thigh of the hind leg. Pulsed electric fields, PEF, with 16 exponentially decaying pulses with a maximum electric field strength of 140 V/mm and t1/e = 1 ms were first applied to the tumors. Then within 5 min radiation therapy with 60Co-gamma radiation, RT, was given in daily fractions of 5 Gy. The animals were arranged into one group of controls and 3 groups of different kind of treatments: PEF only, RT only or combination of PEF + RT. At about 4 weeks after inoculation, the tumors were given the treatment sessions during one week. In 2 experimental series with totally 52 rats with N32 tumors, of which 16 were controls, were given 4 sessions of PEF treatments and RT (totally 20 Gy). In a special experimental series with totally 56 rats with N32 tumors, of which 10 were controls, the different groups were given 1, 2, 3 or 4 treatment sessions respectively, Another strain of glioma tumor, N29 with 62 tumors of which 14 were controls was studied in 2 series given 4PEF + 4RT and 2PEF + 4RT respectively. Fitting the data obtained from consecutive measurements of tumor volume (TV) of each individual tumor to an exponential model TV = TV 0 · exp[TGR · t] estimated the tumor growth rate (TGR % per day) after the first day of treatment (t = 0). The TGR of N32 tumors treated with the combination of 4PEF + 4RT are significantly decreased compared to the controls (p < 0.0001), compared to RT alone (p < 0.0001) and compared to PEF alone (p < 0.001). The combined treatment of N32 gives significant effect on the tumor growth rate after 2, 3 and 4 treatment session while RT alone seems to be most efficient after one treatment of 5 Gy and PEF alone is most efficient after 2 treatments at 2 consecutive days. The TGR of N29 tumors treated with the combination of 4PEF + 4RT are significantly decreased compared to the controls (p < 0.05) but the combination of 2PEF + 4RT was more effective (p < 0.005). The specific therapeutic effect STE is defined as the difference between the average tumor growth rates of controls and exposed tumors divided by the average tumor growth rate of the controls. With 4PEF treatments alone the average STE value was 0.32 for N32 tumors and 0 for N29; for 4RT alone the STE values were 0.29 and 0.42 respectively, and for combined treatments 4PEF + 4RT 0.67 and 0.17 respectively. For the N29 tumors treated with 2PEF + 4RT the STE value was 0.53. The therapeutic enhancement ratio, TER, value increase with the number of treatment sessions and the TER of the combined treatments is above 1 in two of the N32 series, which indicates a synergistic effect of 4PEF + 4RT. This work demonstrate the use of our model for analyzing the combination PEF + RT, but it can also be used for evaluation the therapeutic effects of combining RT with chemotherapy or immunogene-therapy.
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| 8. |
- Persson, Bertil R, et al.
(författare)
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Radiation immunomodulatory gene tumor therapy of rats with intracerebral glioma tumors.
- 2010
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Ingår i: Radiation Research. - 0033-7587. ; 173:4, s. 433-440
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Tidskriftsartikel (refereegranskat)abstract
- Single-fraction radiation therapy with 5 or 15 Gy (60)Co gamma radiation was combined with intraperitoneal injections of syngeneic interferon gamma (IFN-gamma)-transfected cells in rats with intracerebral N29 or N32 glioma tumors at days 7, 21 and 35 after inoculation. For intracerebral N29 tumors, single-fraction radiation therapy with 5 or 15 Gy had no significant effect on the survival time. Immunization with IFN-gamma-transfected N29 cells significantly increased the survival time by 61%. Single-fraction radiation therapy with 5 Gy combined with immunization increased the survival time significantly by 87% and complete remissions by 75% while with 15 Gy the survival time increased 45% with 38% complete remissions. For intracerebral N32 tumors, single-fraction radiation therapy with 15 Gy increased the survival time significantly by 20%. Immunization by itself had no significant effect with IFN-gamma-transfected N32 cells, but combined with 15 Gy single-fraction radiation therapy it increased survival time significantly by 40%, although there were no complete remissions. Based on these findings, we suggest a new therapeutic regimen for malignant glioma using single-fraction radiation therapy with a target absorbed dose of the order of 5-10 Gy combined with clinically verified immunotherapy.
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| 9. |
- Persson, Bertil R, et al.
(författare)
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Survival of rats with N29 brain tumours after irradiation with 5 or 15 Gy and immunization with IFN-gamma secreting tumour cells
- 2008
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Ingår i: BioMedical Engineering and Informatics : New Development and the Future - Proceedings of the 1st International Conference on BioMedical Engineering and Informatics, BMEI 2008 - New Development and the Future - Proceedings of the 1st International Conference on BioMedical Engineering and Informatics, BMEI 2008. - 9780769531182 ; 2, s. 243-247
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Konferensbidrag (refereegranskat)abstract
- Intra cerebral tumours were inoculated into the brain of Fischer-344 syngeneic rats. After one week they were treated with either 5 or 15 Gy of Co-60-gamma radiation. The first immunization was given 1 hour before the radiation treatment and then two more times with 14-day intervals. Immunization was performed with 3 x 10(6) radiation sterilized IFN-gamma secreting tumour cells (N29) injected intraperitoneally. Neither radiation therapy with 5 or 15 Gy nor immunization with N29 cells alone had any significant effect on the length of survival of N29 tumour bearing rats. But radiation therapy with 5 Gy combined with immunization with IFN-gamma secreting syngeneic N29 cells resulted in 63 % complete remissions and significantly (p < 0.05) increased survival for the tumour bearing rats. Corresponding combination with 15 Gy RT resulted in 50% complete remissions. There is a possibility of a synergistic effect by optimal combination of radiation therapy and immunization.
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| 10. |
- Persson, Bertil R, et al.
(författare)
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Treatment of tumour cell with 5-aza-2-deoxycytidine (DAC) for immune tumour therapy of Glioma in Fischer-344 rats
- 2012
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Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2012:007, s. 1-21
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Fisher 344 rats with implanted N29 glioma tumours were treated with Pulsed Electric Fields (PEF) in combination with immunization using either IFN-gamma-gene-transfected syngeneic tumour cells or IFN-gamma transfected N29 cells treated with 10 micro-M 5-aza-2-deoxycytidine (DAC). Tumours (N29) were inoculated subcutaneously on both thighs of female F- 344 syngeneic rats. The left tumour was treated once with 16 exponential pulses with an electric field strength of 1400 V/cm, and 1.0 ms duration (time constant). No anticancer drugs were given at any time. The following day and then once weekly for three weeks, the animals were given intra-peritoneal injections of irradiated, modified N29 tumour cells. The results were evaluated by daily measuring the size of tumour on both sides of the animals. Treatment with solely PEF in 32 animals resulted in a specific growth rate decrease of 20±6 % on the PEF exposed tumour. The effect at the non targeted tumour was negligible (0±4 %). Treatment with IFN-gamma secreting tumour cells resulted in a significant decrease of tumour growth rate on the right tumour of 20± 2 % (p< 0.05) and no significant effect (3±0.3% ) was observed on the left tumour. Immunization with DAC treated IFN-gamma secreting cells in 12 animals showed no significant decreased growth rate, on neither the left nor the right tumours. By combining PEF+IFN-gamma no significant decrease in growth rate was achieved. But in the combination of PEF and IFN-gamma secreting cells grown in DAC medium the tumour growth rate decreased by about 50 % at the PEF treated tumour and there was a decrease of about 20% in tumour growth at the non-PEF treated tumour rate which is about the same as for PEF treatment alone. Immune therapy of rats with intracranial N32 tumours by immunization with IFN-gamma secreting syngeneic cells treated with DAC resulted in a slight (3%) but not significant increase in survival time. With a single RT fraction of 15 Gy there was, however, a significant increase of 32% in the length of survival time of the rats with N32 tumours (p<0.02). Radiation therapy with a single fraction of 15 Gy combined with immunization with IFN-gamma secreting syngeneic cells treated with DAC resulted in significant (p<0.01) 34% increased length of survival time for the N32 tumours although there were no complete remissions.
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