Pathogenreduktion mittels UVC-Licht: Entwicklung des THERAFLEX UV-Plättchen-Systems

Transcription

1 Pathogenreduktion mittels UVC-Licht: Entwicklung des THERAFLEX UV-Plättchen-Systems Pathogen reduction by UVC light: Development of the THERAFLEX UV-Platelets system Fribourg 2011 Prof. Dr. Axel Seltsam, MD MHBA

2 Current PR technologies PR procedure Solvent-Detergent MB INTERCEPT Acellular Plasma and derivates Blood products Platelets Cellular RBCs MIRASOL? Frale (S303)?? THERAFLEX UVC? Procedures targeting cell membranes Procedures targeting ribonucleic acids

3 Target structure: Nucleic acid Pathogens with nucleic acids reproduce by replicating their nucleic acid roadmap. This is a mandatory step for all pathogenic agents except prions.

4 Active principle of THERAFLEX UV-Platelets UVC irradiation + Agitation of loosely placed platelet concentrates

5 Mechanism of action UVC wavelength used: 254 nm

6 Mechanism of action Direct interaction with nucleic acids: Formation of cyclobutane pyrimidine und pyrimidine pyrimidone dimers UVC light Blocking of elongation of nucleic acid transcripts

7 THERAFLEX UV-Platelets Efficient UVC penetration through mixing and a thin layer of platelets Formation of 6-4 photoproducts UVC UVC UVC Platelet concentrate UVC Formation of cyclobutane pyrimidine dimers (Thymine dimers) DNA Optimal UVC exposure UVC-induced before iradiation under agitation DNA damage

8 Procedure

9 Specifications THERAFLEX UV-Platelets Parameter Volume Platelet concentration Specification 350 ml ( ml) /ml Plasma content 35 ± 5 % Ratio plasma : SSP+ 30:70 to 40:60 Seltsam & Müller, Transfus Med Hemother 2011

10 Virus inactivation Virus Model for THERAFLEX UV- Platelets HIV-1 1 West Nile virus (WNV) Sindbis virus HCV 5.3 Encephalomyocarditis virus (EMCV) HAV 4.0 Porcine parvovirus (PPV) Parvovirus B Vesicular stomatitis virus (VSV) 6.3 Suid herpes virus (SHV-1) CMV 2.8 HCV 5.0 Influenza, H3N2 5.3

11 Bacteria inactivation (Spiking)

12 Bacteria inactivation (Spiking) Species Aerobic/ anaerobic Gram stain Spore former Bacillus cereus aerobic ± 0.81 Clostridium perfringens anaerobic Escherichia coli (PEI-B-19) fac. anaerobic Enterobacter cloacae fac. anaerobic Klebsiella pneumoniae (PEI-B-08) fac. anaerobic ± 0.28 Pseudomonas aeruginosa aerobic Reduction factor (log 10 ) Propionibacterium acnes anaerobic ± 1.13 Serratia marcescens fac. anaerobic Staphylococcus aureus aerobic Staphylococcus epidermidis (PEI-B-06) aerobic ± 0.51 Fac.= facultative WHO Repository Transfusion-Relevant Bacteria Reference Strains (WHO RTRBRS)

13 Bacteria inactivation (Sterility)

14 Bacteria inactivation (Sterility)

15 Bacteria inactivation (Sterility) Species 0.83 x standard dose BacT/ALERT results after 6 days* Standard dose 1.33 x standard dose Bacillus cereus 10 sterile, 2 unsterile 12 sterile 11 sterile, 1 unsterile Enterobacter cloacae 12 sterile 12 sterile Escherichia coli 12 sterile 12 sterile 12 sterile Klebsiella pneumoniae 12 sterile 12 sterile 12 sterile Propionibacterium acnes 12 sterile 12 sterile 12 sterile Pseudomonas aeruginosa 12 sterile 12 sterile Staphylococcus aureus 10 sterile, 2 unsterile 12 sterile 12 sterile Staphylococcus epidermidis 12 sterile 12 sterile 12 sterile *Spiking concentration 100 CFU/ml Aerobic as well as anaerobic culture bottles were used Mohr et al., Transfusion 2009

16 Inactivation of leukocytes PBMC spike Spiked Pool PC (1x10 6 PBMC* /ml PC) 350 ml 350 ml 350 ml γ-irradiation untreated UVC-irradiation PBMC removal γ 30 Gy 0 J/cm J/cm J/cm 2 * PBMC: peripheral blood mononuclear cells In vitro assays n=5

17 Proliferation (CPM) Inactivation of leukocytes Stimulation assay Mixed lymphocyte culture 3 H-Thymidine incooperation (cpm) Medium anti CD3/CD28 10 µg/ml PHA Gy UVC J/cm 2 Gamma Treatment untreated Donor H untreated UVC 0.1 UVC 0.2 J/cm 2 Stimulator MNC, medium Responder MNC, medium MLC

18 Parameter In vitro platelet quality Days after UVC irradiation Day 1 Day 4 Day 6 control UVC control UVC control UVC PLT concentration [x 10 9 /ml] 1.19 ± ± ± ± ± ± 0.05 ph 7.17 ± ± ± ± ± ± 0.04 Glucose [mmol/l] 5.9 ± ± ± ± ± ± 0.8 Lactate [mmol/l] 8.5 ± ± ± ± ± ± 1.3 Hypotonic shock response [%] 79 ± 3 68 ± 8 62 ± 0 56 ± 7 57 ± 3 51 ± 1 Collagen-induced aggregation [%] 10 µg/ml collagen Collagen-induced aggregation [%] 2 µg/ml collagen 93 ± 4 93 ± 3 88 ± 4 89 ± 6 68 ± ± 9 33 ± ± 7 23 ± ± 12 7 ± 2 16 ± 7 CD62 [%] 44 ± ± 3 38 ± ± 2 47 ± 4 53 ± 4 Annexin V [%] 4 ± 1 3 ± 1 6 ± 2 6 ± 2 7 ± 2 9 ± 2 PAC-1 binding [Geo mean] 571 ± ± ± ± ± ± 220 significant at p<0.05 (paired t-test) Seltsam & Müller, Transfus Med Haemother 2011

19 Platelet proteome study 1.33 x standard dose Total N=762 Mohr et al., Transfusion 2009

20 Tolerability No addition and/or removal of any photoactive reagent photoreagent-related adverse events excluded Preclinical animal model (Beagle dog): No acute or subchronic toxicity No evidence for immunogenicity Animal group 2 Animal group 1 X 6 X Sampled before UVCirradiation t=1 t=2 t=1 t=2 Sampled after UVCirradiation Transfusion, In press

21 Survival and recovery buffy coat platelets Buffy coat (BC)-derived platelets, stored for 5 days, N=12 Recovery (%) Recovery Survival (d) Survival (d) Fresh Stored % stored vs. fresh Fresh Stored % stored vs. fresh Control group UVC group % reduction treated vs. control N/A Bashir et al., Transfusion 2012

22 Phase I study Monocentric 10 healthy volunteers UVC-treated apheresis platelet concentrates Primary endpoint: safety and tolerance Secundary endpoints: CCI, UVC-specific platelet antibodies

23 Study plan 1.Series 2 days 2 Weeks Study plan 2.Series 2 days 2 Weeks 3.Series Apheresis Sequencial Retransfusion 2 days Apheresis Complete Retransfusion Double Apheresis Double Retransfusion

24 Status phase I study Experiments completed No transfusion-related adverse events No UVC-specific platelet antibodies

25 Summary-THERAFLEX UV-Platelets Simple and rapid procedure Irradiation + agitation (< 60 sec.) Adequate platelet viability and efficacy In vitro parameter Good survival and recovery High efficacy for bacteria and most viruses Inactivation of residual leukocytes Good tolerability No addition and/or removal of any photoactive reagent No evidence for an immune response