Advanced in vitro exposure systems.

15. Nov. 2020

The Comparative Analysis of Cytokine Production by a Human 3D Tissue Model Following Exposure to Traditional Cigarette Smoke, Tobacco-Heated Product and E-Cigarette Aerosol

Rob Bedford1, Emma Rothwell1, Sophie Martin1, Cian O’Hanlon1, Andrew McCune2 and Michael Hollings1
1Genetic and Molecular Toxicology and 2Immunology and Immunotoxicology, Covance Laboratories Ltd., Harrogate, UK

 

- Exposure to 3R4F resulted in increased levels of IL-4, MDC, GM-CSF, IL-12/IL23p40, IL-10 and IFN-γ in the recovery media. Approximately three-fold increases in MDC, GM-CSF, IL-12/IL23p40 and IFNγ were observed whilst two-fold increases were observed for IL-4 and IL-10. In comparison, no marked effect was observed in the module media.

- In contrast to the response observed from 3R4F exposure, fewer changes in cytokine production were observed following THP and E-cigarette exposure. IFNγ demonstrated a two-fold increase in levels measured in the recovery media at doses 1 and 2 for THP. IL-12/IL23p40 also demonstrated a 1.5-fold increase in recovery media following exposure to THP. In addition, IFN-γ and IL-8 were increased following exposure to E-cigarette at dose 2. IL-1β also demonstrated a 1.5-fold increase in the recovery and module media following exposure to E-cigarette.

- A number of cytokines were reduced following exposure to THP and E-cigarette. For example, GM-CSF, MIP1α, VEGF and MCP-1.

- These results demonstrate the difference in cytokine profiles of MucilAir tissues following exposure to different nicotine-containing products.

 

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27. Jul. 2020

Vitrocell® holder systems for e-cigarettes

Secure and tight connection of any device to the smoking machine.

New designs of electronic cigarettes such as ENDS (Electronic Nicotine Delivery Systems) products or HTP (Heated Tobacco Products) lead to a large variety of different shapes which make the insertion into conventional holders with labyrinth seals impossible. VITROCELL® has developed a new holder system which is flexible to adjust to different shapes.

VITROCELL Application Note

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13. Jul. 2020

An experimental aerosol air–agar interface mouse lymphoma assay methodology

DOI: https://doi.org/10.1016/j.mrgentox.2020.503230 

Authors
Thorne D1, Hollings M2, Kilford J2, Clements J2, Payne R2, Ballantyne M2, Dalrymple, A1, Dillon, D1, Meredith, C1, Gaҫa, M1  
 
1 British American Tobacco, R&D, Southampton, Hampshire SO15 8TL, UK. 
2 Covance Laboratories Ltd, Otely Road, Harrogate, HG1 PY, UK

 

Highlights

  • An experimental concept of exposing L5178Y cells at the air-agar-interface
  • Cells were lightly seeded on an agar surface to achieve exposure
  • Flowing air, plating and recovery efficiencies from the agar-surface were investigated
  • Positive controls were responsive, suggesting a clear cellular interaction with the agar-matrix 
  • Cigarette smoke aerosol showed a dose-response relationship with increasing mutant frequencies

 

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24. Feb. 2020

In vitro advances in whole aerosol approaches for e-cigarette testing

IIVS Workshop 3, Feb 24-26th 2020

Autor

David Thorne, British American Tobacco

 

Workshop series to identify, discuss and develop recommendations for the optimal generation and use of in vitro data for product regulation.

 

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31. Dec. 2019

High Throughput Air Liquid Interface Exposure Modules: Characterization of Smoke/Aerosol Dosimetry and in vitro Mutagenicity and Cytotoxicity of Two Tobacco Product Types

Robert Leverette1, Brian Keyser1, Michael Hollings2 and Adam Seymour2
1RAI Services Company, Winston−Salem, NC 27101 USA
2Covance Laboratories Ltd., Harrogate, North Yorkshire HG3 1PY, UK

 

• Freshly generated whole smoke / aerosol from three different tobacco product types (3R4F, THP and ENDS) was consistently delivered within the AMES 48 and 6/48 exposure modules.
• Biological endpoints: 3R4F whole smoke induced increased revertant counts (Ames) and cytotoxicity (NRU) in the AMES 48 and 6/48 modules, respectively.
• Revertant counts (Ames) and cytotoxicity (IC50) values were comparable to those from the standard exposure modules when run under similar exposure conditions.
• Overall, the AMES 48 and 6/48 modules are deemed “Fit for Use" for the in vitrO evaluation of different tobacco product types (combustible, THP, ENDS).
 

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30. Nov. 2019

Characterization of Whole Mainstream Smoke/Aerosol Delivery within the Vitrocell® Ames 48 High Throughput Exposure Module Using Different Tobacco Product Types.

1Leverette R, 1Keyser B, 2Seymour A and 2Hollings M
1Scientific & Regulatory Affairs, RAI Services Company, Winston-Salem, NC 27101
2Covance Laboratories Ltd, Otley Road, Harrogate, North Yorkshire HG3 1PY, UK

 

  • Freshly generated whole smoke from the 3R4F reference cigarette (HCI; TPM) and aerosol from either a commercially available THP (HCI; glycerol) or ENDS (CRM81; glycerol) were delivered consistently within the Vitrocell® AMES 48 High Throughput exposure module.
  • Coefficients of variation (CV) for whole smoke/aerosol deposition within each dose (row) were < 20% (3R4F; TPM) and < 15% (THP and ENDS; glycerol).
  • Overall, the data presented demonstrate the consistent delivery of whole smoke/aerosol under controlled conditions and a reproducible in vitro biological response (Ames) with the Vitrocell® AMES 48 High Throughput exposure module. HCI 3R4F whole smoke exposures do require additional range finding experiments for optimization.
  • Ames activity of 3R4F whole smoke, when generated under similar conditions, was comparable when using either the Vitrocell® AMES 48 High Throughput exposure module or the Vitrocell® Standard exposure modules (Figure 6).
  • The Vitrocell® AMES 48 exposure module is a useful tool to increase sample throughput for the in vitro toxicological assessment of freshly generated whole smoke and aerosols from different tobacco product types (combustible, THP and ENDS). The AMES 48 module allows 7 smoke/aerosol doses (with 6 cultures per dose) per exposure versus only 2 (HCI) - 4 (ISO) doses (with 3 cultures per dose) for the standard exposure modules (when using a VC10® smoking machine).

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30. Nov. 2019

Dosimetric Analysis of Aerosol Generated by a Vitrocell® VC10® Smoking Robot – Investigations on Dose Dependency and Consistency of Application


Adam Seymour, Michael Hollings, Joanne Larner and Julie Clements;

Covance Laboratories Ltd, Harrogate, UK


QCMs were used to assess the deposition of cigarette aerosol from a Vitrocell® VC10® in Vitrocell® Ames, 6/4, 12/4 and 24/4 exposure modules. The power to resolve difference between 8 and 1 SLPM is statistically significant in all module types assessed. Uniformity within each module was confirmed (P >0.98) in all module types, at all airflows. Repeatability was assessed and found to be consistent (no significant difference) in all module types at airflows of 10, 8 and 4 SLPM, however, at 1 SLPM a significant difference was noted in 9 out of 12 experiments – likely an artifact of high deposition.
These results show that exposures utilizing the Vitrocell® VC10® and associated modules are robust; but indicate the necessity of dosimetry measures to aid in the quantification of delivered dose.
 

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4. Nov. 2019

Investigation of multiple whole smoke dosimetry techniques using a VITROCELL®VC10® smoke exposure system

https://doi.org/10.1016/j.toxrep.2019.10.011

Brian M. Keysera, Robert Leverettea, Michael Hollingsb, Adam Seymourb, Lesley Reeveb, Wanda Fieldsa
a RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC, 27101, USA1
b Covance Laboratories Ltd., North Yorkshire, UK

 

Highlights
• Investigation of dose-determining methods using the Vitrocell® VC10® system.
• Dose assessment using Quartz Crystal Microbalances (QCM) and aerosol photometers.
• Dose assessment using fluorescence of DMSO-captured smoke constituents.
• QCM, photometer AUC, and DMSO-captured matter were consistent and reproducible

 

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25. Oct. 2019

VITROCELL® High Throughput Exposure Module: Deposition and Cytotoxicity of Smoke/Aerosol from Different Tobacco Product Types

User Group Meeting 2019

1Leverette R, 1Keyser B, 2Seymour A, 2Hollings M and 1Bombick B
1Scientific & Regulatory Affairs, RAI Services Company Winston-Salem, NC 27102
2Covance Laboratories Ltd Otley Road, Harrogate, North Yorkshire HG3 1PY, UK

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25. Oct. 2019

New holder for ENDS products for VITROCELL® Smoking Machines and Robots

User Group Meeting 2019

Bastian Gutmann, Tobias Krebs
VITROCELL Systems GmbH 79183 Waldkirch, Germany

The poster shows the new holder for ENDS products

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