Study type: Medical/biological study (experimental study)

Millimeter wave induced reversible externalization of phosphatidylserine molecules in cells exposed in vitro. med./bio.

Published in: Bioelectromagnetics 2006; 27 (3): 233-244

Aim of study (acc. to editor)

To study the effects of millimeter waves on thrombogenic activity and phosphatidylserine externalization in various human and murine cells.

Background/further details

Phosphatidylserine (PS) is a key phospholipid component of eucaryotic cell membrane and found almost exclusively on inner leaflet of the plasma membrane lipid bilayer in normal healthy cells. PS externalization is an important physiological signal (for example, in the apoptotic process).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 42.25 GHz
Exposure duration: continuous for 30 min
Exposure 2: 42.25 GHz
Modulation type: CW
Exposure duration: continuous for 30 min

General information

Sham exposure were performed under the same conditions as the real exposureexcept that the MMW generators were not energized.

Exposure 1

Main characteristics
Frequency 42.25 GHz
Charakteristic
  • guided field
Exposure duration continuous for 30 min
Modulation
Modulation type unspecified
Exposure setup
Exposure source
Distance between exposed object and exposure source 1 mm
Parameters
Measurand Value Type Method Mass Remarks
power density 0.55 W/cm² spatial average unspecified - -
power density 1.23 W/cm² spatial average unspecified - -

Exposure 2

Main characteristics
Frequency 42.25 GHz
Charakteristic
  • guided field
Exposure duration continuous for 30 min
Modulation
Modulation type CW
Exposure setup
Exposure source
Distance between exposed object and exposure source 1 mm
Parameters
Measurand Value Type Method Mass Remarks
power density 34.5 mW/cm² peak value unspecified - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • before exposure
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

Fluorescence microscopy of the adherent human keratinocytes and murine melanoma cells showed that millimeter wave exposure at an incident power density of 1.23 W/cm² is capable of inducing reversible externalization of phosphatidylserine molecules in cells within the beam area without detectable membrane damage.
Non-adherent Jurkat cells exposed to millimeter wave at an incident power density of 34.5 mW/cm² also showed reversible phosphatidylserine externalization with flow cytometry, whether the cell temperature was held constant or permitted to rise.
These data suggest that certain biological effects induced by millimeter waves could be initiated by membrane changes in exposed cells.

Study character:

Study funded by