= LhARA radiobiology; meeting: 23Jul26; 14:00 GMT =

**ZOOM:** https://imperial-ac-uk.zoom.us/j/98220889714?pwd=SM90vOF7BKSXoU3mD9q7OwBQo4IVB3.1 

== Meeting Notes == 

Attended: KL, CD, JMcG, AG, JB, PP, AFr, AT, BS, CW, DA, GS, JuP, MD, MH, NK, RH, RA, RW

1. Long-term LhARA Biology Plan
- KL: Presentation [raw-attachment: Slides]
 - Radiobiology is a key component throughout the LhARA program
  - Aim for the program to be definitive
  - Must be multi-disciplinary. Have to do the radiobiology but in new ways
  - Multi-national: Need greater expertise
  - Multisource: laser-driven, electrons, X-rays, and gamma-rays for reference sources
  - Multi-messenger: Diverse cell lines, diverse markers (need to integrate automation)
  - Systematic: Same conditions at a variety of sources across borders
  - AI-enabled: Consistent sample handling and irradiation
   - Interpretation: AI as well to develop more on TOPAS and G4DNA
- JMcG: Presentation [raw-attachment: Slides]
 - Long-term vision of a facility that can support: FLASH, SFRT, Advanced Imaging and Beam Monitoring
 - PoPLaR Current Vision:
  - Improve setup and workflow protocols and instrumentation needed
  - Becomes a comparison against X-ray and cyclotron proton beams
  - Measuring: Clonogenics, Comet assays, Fixed IF (immunofluorescence) imaging
 - Live Cell Imaging:
  - Understand underlying mechanisms in real-time
  - Builds on Tony's SFRT work and FLASH comparisons
  - Biggest limitation on previous fixed IF SFRT work was only able to compare different cell samples at each time point.
   - Live cell imaging would help fix this.
- General Discussion
 - Strong agreement that comparison between laser-driven and cyclotron is key.
 - Next vary the beam, looking at FLASH and SFRT
  - Agreement that this needs to focus on particular biological hypotheses
  - Need to understand mechanisms being discussed behind both and what the current hypotheses are
   - Review literature 
    - Literature review: Mechanisms, challenges and opportunities for FLASH radiotherapy in cancer Marie-Catherine Vozenin  1   2 , Pierre Montay-Gruel  3   4 , Pelagia Tsoutsou  5   6 , Charles L Limoli  7 DOI: 10.1038/s41568-025-00878-9
   - Invite experts in: Jason et al, Yolanda et al, Dresden group, Maria Catherine at PSI
    - Also, input from Jason, Emma, Marie and Katya (Munich) about what they expect at each stage as the instrumentation and beamline gets better.
   - Identify which hypotheses LhARA is uniquely capable of testing
   - **Josie to coordinate**
 - Strong agreement to start developing live cell imaging techniques now so when the beamline is ready it is ready.
 - Warning that if we do not see differences at the cell level does not mean there is no difference at the tissue or for whole organisms
 - Strong agreement that dosimetry must be included from the outset

2. Overview of Current SCAPA Plan 
- Solutions to the three main problems:
 - Move the scatterer further up the beamline (closer to the laser-target).
 - Use a real-time diagnostic
 - Investigate how long the cells survive and the cause of death
- Additions:
 - Collect more biology results?
- When?:
 - Confirmation: earliest possible beamtime is February, as this is when the tape drive is being put back in.
- More information: https://docs.google.com/document/d/1OTARVtxhLRu02S6CLdRDB2QlGvCqDfZ3aWBifjIFs_Q/edit?tab=t.0
- Steps required: Below and at https://trello.com/invite/b/67587c515b0c69656ee78b48/ATTIe86f94b24e3e5884e4cb87e5ed3b89ab64321B83/poplar

3. Instrumentation Discussion
- Options:
 - Sparse scintillating fibre arrays in the vacuum chamber
 - Scintillating fibre around the cell dish
 - Lanex around the cell dish
 - Integrated Current Transformers (ICTs)
 - Laser Diagnostics (Backscatter etc)
 - Replace the scatterer with a scintillating sheet
 - (RCF around the cell dish (if desperate))
 - Discussion:
  - Other diagnostics:
   - Should include Liverpool's fluorescence.
    - **Colin to contact Narender about implementation**
   - Suggestion to use the fast electrons as a diagnostic
   - Nick also has his ToF for future times when we have money
  - Scifi:
   - Test clear fibre in a beam. If it scintillates then can use it in the scifi array. If it doesn't can use it to transport the light out the vacuum chamber from the scifi array
    - Robbie offered to test at ELI. He leaves on the 16th August.
     - **Ken and Calvin to send to SCAPA before then (Contact Ewan or Colin since Robbie is USA)**
    - If no time can always test at Swansea or Birmingham
  - Lanex:
   - Fear of Lanex quenching at high rep rates but this is more of a concern near the laser target rather than at the cell dish
 - Testing Method:
  - Agreement that we should calibrate with RCF before hand
  - However, also calibrate a batch of RCF that is scanned after a shorter time period (not 24/48 hrs)
   - Use this for continuous calibration of whichever diagnostic is used during cell irradiations

4. BioPrep Discussion
- Spatial Variation: Is a CV of 8% acceptable?
 - Diaza has read a lot of literature that says 5% should be the maximum
 - Need to figure out how to improve the beamline (Move PMQs)
- Cell Control Survival:
 - Need to test how long cells can remain vertical
  - **Josie to plan a test**
   - Investigate:
    - Vertical or time out of incubator
    - Emma/Jason's HeLa cell line
    - Marie's cell line
  - Also look at evolving a group of cells that can survive the Mylar
 - Can reduce the time taken to conduct the irradiations (and therefore the time the cells are vertical for)
 - Monitor the temperature of the thermostat
- Better instrumentation:
 - Emma and Jason looking at a glass ring setup so that the cells could remain submerged in media
  - Potential to leak...
 - Investigate thicker Mylar as less likely to poke through with pipette
  - Can get up to 1mm Mylar
 - There is an inverted microscope for £250: Openflex 3D printable one with raspberry pi. Could automate counting?
- More results (as well as clonogenics):
 - Comet analyses
  - Agreed to do
 - X-ray comparison on-site
 - IF:
  - Very useful for SFRT
  - Also, provides a potential internal dosimeter: 30 dots = 1Gy
   - Could store two samples and use one as the dosimeter
   - Would have to be consistent with when the cells are fixed and stained
   - Need to test further: **Josie to look into this. Discuss with Emma**
  - Concern is the labour to check at every timepoint

5. Alternate Beamlines
 - ELI Rejected
  - Waiting for feedback
   - Robbie says they usually give good feedback and much easier to get beamtime on the second try

6. Discussion on Ion-Acoustic Plan
 - Current updates
 - No time

7. DoNM 
 - 06/08/26

8. AoB
- Richard: Proton beams at Medical Director Holland PTC. FLASH enabled, and they are actively looking to offer the beam out for experimentation. In Amsterdam. Timeline: Available now but not sure how many other people have started to apply. Write a paragraph about what they wanna do. Did not mention cost. 

=== Summary of actions required ===

In-Beam Diagnostics
- **Unassigned**: Acquire a glass sheet
- **Unassigned**: Get a new RCF batch and calibrate
- **TP**: Testing delaminating EBT3
- **PH**: Obtain transparent fibre or an alternative method for light transport
- **PH**: Obtain a lens for hollow fibre tests
- **CD**: Simulate energy deposited in transport fibres
- **KL, CD, JMcG, PH**: Design a system to make full scifi prototypes
- **KL, CD, JMcG, PH**: Make a full scifi prototype
- **KL, CD**: Send clear fibre to SCAPA before 16th August (Contact Ewan or Colin since Robbie is USA)
- **KL, CD, JMcG, PH**: Discuss visit to Birmingham to test SciFi
- **RW, CD**: Study the correlation between laser diagnostics and mean dose
- **Unassigned**: Investigate how a phosphor sheet could be incorporated into the design of the cell dish
- **CW**: Investigate the feasibility of ICTs for our beamline
- **MH**: Investigate LET detector
- **CW**: Ask Narender about air fluorescence implementation
- **JMcG**: Investigate using IF as a dosimeter


Bio Next Steps
- **EM, CD, JMcG**: Write up technical summary of Phase 2
- **EM**: Write up a biology plan for a 2 PMQ setup
- **Unassigned**: Obtain an inverted microscope
- **Unassigned**: Obtain multi-chamber haemocytometers (Might be able to use Birmingham's)
- **Unassigned**: Obtain a thermostat for the incubator
- **EM**: Run controls to examine how long the cells can survive vertically
- **JMcG**: Plan a test of vertical cell survival using Emma/Jason's HeLa cell line and Marie's cell line
- **JMcG**: Produce a HeLa colony that can survive on Mylar

Beamline Modelling
- **CD**: Examine energy spectra variation
- **RW, CD**: Source characterisation

Alternate Beamlines
- **JMcG**: Simulate BELLA
- **JMcG**: Simulate ELI

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