SECONDA CONFERENZA DEI PROGETTI DEL CENTRO FERMI
19-20 APRILE 2012
SALONE DELLE CONFERENZE DEL MINISTERO DELL’INTERNO
ROMA, PIAZZA DEL VIMINALE 1
In vitro-In vivo MUrine coSmiC siLEnce
experiment (MUSCLE)
D. Capece and E. Fratini (Centro Fermi)
on behalf of the Cosmic Silence Collaboration
Aim of MUSCLE Project
To understand the biological effects of environmental radiation
Peculiar low dose radiation
effects (<100mGy)
 Bystander effect
Phenomenon in which unirradiated cells exhibit irradiated
effects as a result of signals received from nearby
irradiated cells.
Peculiar low dose radiation
effects (<100mGy)
 Genomic instability
Phenomenon characterized by an increase in the genetic
spontaneous alteration observed in cells which have not
themselves been irradiated, but are the progeny of an
irradiated cell.
Peculiar low dose radiation
effects (<100mGy)
Conditioning Dose
Challenge Dose
Damage
 Adaptive reponse
Phenomenon that occurs when a low dose of mutagenic
agent can protect from the biological damage of a
subsequent high dose of the same or different mutagenica
agents
+
Our Hypothesis
Life has evolved on Earth for 3 bilion years in the presence of environmental
ionizing radiation. All organism have therefore incorporated in their normal
biology a daily stiimulus of ultra-low-dose environmental radiation that
might act as conditioning agent.
LNGS – The Gran Sasso
underground laboratory
LNGS – Internal Labs
1400 m
Teramo
Roma
INFN-LNGS
Past Experiments
Satta et al., 1995.
Satta et al., 2002.
Antonelli et al., 2008.
S. Cerevisiae cells
Chinese
Hamster cells
Carbone et al., 2009.
Carbone & Pinto et al., 2010.
Human cells
S. Cerevisiae D7 cells
Satta et al., Mutat. Res. 1995.
Chinese Hamster V79
Satta et al., Radiat. Environ. Biophys 2002.
Antonelli et al., Nuovo Cimento B 2008.
TK6 Lymphoblastoid cells
Carbone et al., Radiat. Environ. Biophys 2009.
Carbone & Pinto et al., Nuovo Cimento B 2010.
…Summarizing…
Compatible with our hypothesis of environmental radiation as a conditioning
agent, reduced environmental radiation conditions seem to render cells, after
several months of protracted culture:
 Less tolerant to radiation-induced DNA damage
 Less efficient in scavenging reactive oxygen species
pKZ1 Mouse Model
An ideal model for studying responses to very low doses of DNA damaging
agents
Matsuoka et al., Science 1991
pKZ1 Chromosomal Inversion
Assay
P
ZcaL
DNA Inversion
P
LacZ
LacZ Expression
Matsuoka et. al., Science 1991
Experimental design
To use pKZ1 mouse chromosomal inversion assay to study biological effects
of environmental background radiation
 A11 Hybridoma cell line obtained from pKZ1 a splenocyte
 Immortalized cell lines from brain and skin of neonatal pKZ1 mice
Day et al., Radiat. Res. 1991
Experimental design
Reference environmental
radiation (~ 2mGy/year)
Reduced environmental
radiation (~ 25mGy/year)
Istituto Superiore di Sanità
Rome
LNGS - INFN
ISS (External/Reference
Laboratory)
LNGS (Underground
Laboratory)
Cosmic Rays
30 nGy/h
Negligible
Cosmic and terrestrial grays
300 nGy/h
3.6 nGy/h
222Rn
1.7 nGy/h
0.17 nGy/h
Total dose rate
~ 330 nGy/h
~ 3.8 nGy/h
Environmental
Radiation Compnents
Experimental design
ISS – Reference
Environmental Radiation
LNGS – Reduced
Environmental Radiation
Rome
Biological End-points
 Inversion frequency
 Doubling Time
 Rate of apoptosis/autophagy
 Redox cellular state
Teramo
Perspectives
What happens in vivo
Reference Environmental Radiation
L’Aquila University
pKZ1
?
Reduced Environmental Radiation
LNGS (L’Aquila)/LSC-Canfranc
underground laboratory (Saragozza)?
pKZ1
Cosmic Silence Collaboration
CENTRO FERMI
D. Capece, E. Fratini, M.C. Carbone, M. Pinto
INFN
L. Satta
Istituto Superiore di Sanità
G. Simone, M.A. Tabocchini
ENEA Casaccia
R. Amendola
L’Aquila University
F. Zazzeroni, E. Alesse
Flinders University, Adelaide
P. Sykes
ENEA
R. Amendola
INFN-LNGS
M. Balata