ICEmB

ICEmB

Capri, September 29 - October 2 2002

THz exposure of whole blood for the study of

biological effects on human lymphocytes

M. R. Scarfì, M. Romanò, R. Di Pietro, O. Zeni

CNR-IREA Napoli (I)A.Doria, G. P. Gallerano, E. Giovenale, G. Messina, A. Lai,

G. Campurra, D. Coniglio, M. D’ArienzoENEA – FIS-ACC Frascati (I)

ICEmB

Capri, September 29 - October 2 2002

To study the potential health hazard of THz radiation since very little is known about its

interaction with biological systems

Specialised personnel and users in the laboratory-scale THz sources in use at research labs

technical personnel and future patient exposure due to recent technological applications of THz radiation

in biology and medicine, based on the specific spectroscopic fingerprints of biological matter in this

spectral region

ICEmB

Capri, September 29 - October 2, 2002

Genotoxic effects a close correlation exists between DNA damage and cancer

occurence

Human peripheral blood lymphocytes

well known biological model

Cytogenetic techniques cytokinesis block MN assay is a very sensitive and simple

indicator of chromosome damage, which also provides information

on cell cycle progression

AIM: to study MN induction in HPBL exposed in G0 phase to 120 and 130 GHz THz radiation

ICEmB

Capri, September 29 - October 2, 2002

THz Irradiation Compact FEL Facility at the ENEA Research Center

a

b

cd

a = light pipeb = TDSc = right-angle bendd = pyroelectric detector

ICEmB

Capri, September 29 - October 2, 2002

Absorption measurements on whole blood at 120 GHz

Optimal thickness of the sample: 1 mmOptimal irradiation geometry to contain a minimum useful whole blood volume of 2 ml: Petri dishes with internal diameter of

52 mm

ICEmB

Capri, September 29 - October 2, 2002

f Bunch durat.

Bunchinterv.

Pulse durat.

Pulse rep. rate

Aver.power

Irrad. time

Delivered energy

120 GHz

50 ps 330 ps

4 µs 2 Hz 1 mW 20 min.

1.20 J

130 GHz

50 ps 330 ps

4 µs 2 Hz 0.6 mW

20 min.

0.72 J

Irradiation Parameters

ICEmB

Capri, September 29 - October 2, 2002

Blood collectionat the ENEA occupational health unitby venipuncture in heparinized vacutainers

Donors9 healthy subjects aged between 30 and 45 years (mean age: 39.33 ± 4.82 y)

neither therapeutic drugs nor diagnostic X rays

ICEmB

Capri, September 29 - October 2, 2002

Biological procedurefor each donor, 3 conditions:

• exposed• sham exposed• control

2 ml wb in 52 mm Petri dishes

Sham exposure rationale: to simulate the same environmental conditions of exposed samples, but in absence of radiation

ICEmB

Capri, September 29 - October 2, 2002

Lymphocyte cultures

Following 20 min. exposure/sham exposure, 0.8 ml wb in 9.2 ml RPMI 1640 medium containing 15% FCS, 2 mM L-Glutamine and 100 µl PHA

control cultures handled in parallel

ICEmB

Capri, September 29 - October 2, 2002

Cytokinesis-block micronucleus assay

Screening MN frequency: % CB cells containing MN/1000 CB cellsCBPI: by classifying 500 cells according to the n° of nuclei

[M1 + 2M2 + 3(M3+M4)/N]

Statistical analysistwo tailed paired Student’s t test

t=0 t=44h t=72h x - - - - - - - - - - - - - - - - - - - - x- - - - - - - - - - - - - - x | | | Start cyt- B harvest and (PHA) slide preparation

ICEmB

Capri, September 29 - October 2, 2002

1000X

ICEmB

Capri, September 29 - October 2, 2002

MN frequency in HPBL cultures following THz radiation exposure in G0 phase (9

subjects)at 120 and 130 GHz

00,20,40,60,8

1

120 GHz 130 GHz

Exposure frequency

MN

freq

uenc

y

controlshamexposed

P>0.05

120 GHz – 6 donors130 GHz – 3 donors

ICEmB

Capri, September 29 - October 2, 2002

CBPI in HPBL cultures following THz radiation exposure in G0 phase (9

subjects) at 120 and 130 GHz

00,5

11,5

22,5

120 GHz 130 GHz

Exposure frequency

CB

PI

controlshamexposed

P>0.05

ICEmB

Capri, September 29 - October 2, 2002

Conclusions• Environmental condition at FEL laboratory does not

influence MN induction and cell cycle kinetics of HPBL (sham/control);

• THz exposure of HPBL, at both 120 and 130 GHz: does not affect MN formation;

does not influence cell proliferation (sham/exposed).

Ongoing studies on a larger number of individuals should provide further, more complete information on

this topic.

ICEmB

Capri, September 29 - October 2, 2002

Future work• exposed/sham exposed

• different exposure conditions: f (following input from WP1); power levels

• modulation conditions: still open•possibility of extending the irradiation measurements to the range 1-10 THz at

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