Limits...
Peripheral neural cell sensitivity to mTHPC-mediated photodynamic therapy in a 3D in vitro model.

Wright KE, Liniker E, Loizidou M, Moore C, Macrobert AJ, Phillips JB - Br. J. Cancer (2009)

Bottom Line: MCF-7s and satellite glia were significantly more sensitive to PDT than neurons.Importantly, 4 microg ml(-1) mTHPC-PDT caused no significant neuron death compared with untreated controls but was sufficient to elicit substantial cell death in the other cell types.Initially, treatment reduced neurite length; neurons then extended neurites equivalent to those of untreated controls.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Department, The Open University, Milton Keynes MK7 6AA, UK.

ABSTRACT

Background: The effect of photodynamic therapy (PDT) on neural cells is important when tumours are within or adjacent to the nervous system. The purpose of this study was to investigate PDT using the photosensitiser, meta-tetrahydroxyphenyl chlorin (mTHPC), on rat neurons and satellite glia, compared with human adenocarcinoma cells (MCF-7).

Methods: Fluorescence microscopy confirmed that mTHPC was incorporated into all three cell types. Sensitivity of cells exposed to mTHPC-PDT (0-10 microg ml(-1)) was determined in a novel 3-dimensional collagen gel culture system. Cell death was quantified using propidium iodide and cell types were distinguished using immunocytochemistry. In some cases, neuron survival was confirmed by measuring subsequent neurite growth in monolayer culture.

Results: MCF-7s and satellite glia were significantly more sensitive to PDT than neurons. Importantly, 4 microg ml(-1) mTHPC-PDT caused no significant neuron death compared with untreated controls but was sufficient to elicit substantial cell death in the other cell types. Initially, treatment reduced neurite length; neurons then extended neurites equivalent to those of untreated controls. The protocol was validated using hypericin (0-3 microg ml(-1)), which caused neuron death equivalent to other cell types.

Conclusion: Neurons in culture can survive mTHPC-PDT under conditions sufficient to kill tumour cells and other nervous system cells.

Show MeSH

Related in: MedlinePlus

Neurons survive mTHPC-mediated PDT and produce new neurite outgrowth. After treatment with mTHPC-mediated PDT in 3D culture, neurons were grown in 2D in the presence of untreated satellite glia for 2 days. A similar number of neuronal cell bodies had neurites associated with them in the 3–4 μg ml–1 mTHPC-mediated PDT samples as in the controls (A). There was a similar level of neurite length detected in controls and treated neurons, except for the samples that had received 10 μg ml–1 mTHPC-mediated PDT, which showed a significant reduction in neurite length (*P<0.05) (B).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2736832&req=5

fig6: Neurons survive mTHPC-mediated PDT and produce new neurite outgrowth. After treatment with mTHPC-mediated PDT in 3D culture, neurons were grown in 2D in the presence of untreated satellite glia for 2 days. A similar number of neuronal cell bodies had neurites associated with them in the 3–4 μg ml–1 mTHPC-mediated PDT samples as in the controls (A). There was a similar level of neurite length detected in controls and treated neurons, except for the samples that had received 10 μg ml–1 mTHPC-mediated PDT, which showed a significant reduction in neurite length (*P<0.05) (B).

Mentions: Having established that PDT with 3, 4 and 10 μg ml–1 mTHPC resulted in a low level of neuronal death in the 3D culture system, the ability of ‘spared' neurons to sprout neurites was investigated. After PDT, neurons (along with remaining glia and dead cells) were harvested from collagen gels using enzymatic digestion, mixed with untreated satellite glia, then seeded in a monolayer culture. Figure 6A shows the numbers of β-III-tubulin immunoreactive neuronal cell bodies that showed neurite growth at 2 days after transfer to monolayer culture. Similar numbers of neurons were detected in control, light only and 3 and 4 μg ml–1 mTHPC-mediated PDT samples, although there were approximately one-third as many neurons detected in the 10 μg ml–1 mTHPC-mediated PDT sample. There were similar numbers of neurons without neurite growth in all groups. Overall, it is apparent that neurons treated with 3 and 4 μg ml–1 mTHPC-mediated PDT showed no difference to untreated and light-only controls in their ability to produce neurites.


Peripheral neural cell sensitivity to mTHPC-mediated photodynamic therapy in a 3D in vitro model.

Wright KE, Liniker E, Loizidou M, Moore C, Macrobert AJ, Phillips JB - Br. J. Cancer (2009)

Neurons survive mTHPC-mediated PDT and produce new neurite outgrowth. After treatment with mTHPC-mediated PDT in 3D culture, neurons were grown in 2D in the presence of untreated satellite glia for 2 days. A similar number of neuronal cell bodies had neurites associated with them in the 3–4 μg ml–1 mTHPC-mediated PDT samples as in the controls (A). There was a similar level of neurite length detected in controls and treated neurons, except for the samples that had received 10 μg ml–1 mTHPC-mediated PDT, which showed a significant reduction in neurite length (*P<0.05) (B).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2736832&req=5

fig6: Neurons survive mTHPC-mediated PDT and produce new neurite outgrowth. After treatment with mTHPC-mediated PDT in 3D culture, neurons were grown in 2D in the presence of untreated satellite glia for 2 days. A similar number of neuronal cell bodies had neurites associated with them in the 3–4 μg ml–1 mTHPC-mediated PDT samples as in the controls (A). There was a similar level of neurite length detected in controls and treated neurons, except for the samples that had received 10 μg ml–1 mTHPC-mediated PDT, which showed a significant reduction in neurite length (*P<0.05) (B).
Mentions: Having established that PDT with 3, 4 and 10 μg ml–1 mTHPC resulted in a low level of neuronal death in the 3D culture system, the ability of ‘spared' neurons to sprout neurites was investigated. After PDT, neurons (along with remaining glia and dead cells) were harvested from collagen gels using enzymatic digestion, mixed with untreated satellite glia, then seeded in a monolayer culture. Figure 6A shows the numbers of β-III-tubulin immunoreactive neuronal cell bodies that showed neurite growth at 2 days after transfer to monolayer culture. Similar numbers of neurons were detected in control, light only and 3 and 4 μg ml–1 mTHPC-mediated PDT samples, although there were approximately one-third as many neurons detected in the 10 μg ml–1 mTHPC-mediated PDT sample. There were similar numbers of neurons without neurite growth in all groups. Overall, it is apparent that neurons treated with 3 and 4 μg ml–1 mTHPC-mediated PDT showed no difference to untreated and light-only controls in their ability to produce neurites.

Bottom Line: MCF-7s and satellite glia were significantly more sensitive to PDT than neurons.Importantly, 4 microg ml(-1) mTHPC-PDT caused no significant neuron death compared with untreated controls but was sufficient to elicit substantial cell death in the other cell types.Initially, treatment reduced neurite length; neurons then extended neurites equivalent to those of untreated controls.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Department, The Open University, Milton Keynes MK7 6AA, UK.

ABSTRACT

Background: The effect of photodynamic therapy (PDT) on neural cells is important when tumours are within or adjacent to the nervous system. The purpose of this study was to investigate PDT using the photosensitiser, meta-tetrahydroxyphenyl chlorin (mTHPC), on rat neurons and satellite glia, compared with human adenocarcinoma cells (MCF-7).

Methods: Fluorescence microscopy confirmed that mTHPC was incorporated into all three cell types. Sensitivity of cells exposed to mTHPC-PDT (0-10 microg ml(-1)) was determined in a novel 3-dimensional collagen gel culture system. Cell death was quantified using propidium iodide and cell types were distinguished using immunocytochemistry. In some cases, neuron survival was confirmed by measuring subsequent neurite growth in monolayer culture.

Results: MCF-7s and satellite glia were significantly more sensitive to PDT than neurons. Importantly, 4 microg ml(-1) mTHPC-PDT caused no significant neuron death compared with untreated controls but was sufficient to elicit substantial cell death in the other cell types. Initially, treatment reduced neurite length; neurons then extended neurites equivalent to those of untreated controls. The protocol was validated using hypericin (0-3 microg ml(-1)), which caused neuron death equivalent to other cell types.

Conclusion: Neurons in culture can survive mTHPC-PDT under conditions sufficient to kill tumour cells and other nervous system cells.

Show MeSH
Related in: MedlinePlus