Direct ultrastructural imaging of macrophages using a novel x-ray contact microscopy.
A compact, high-resolution, laser-plasma, x-ray contact microscopy method using a table-top Nd:glass laser system has been developed. This x-ray microscopy system was applied for the observation of macrophage ultrastructures. These images were produced using proximity imaging in which a 5-ns pulse of soft x-rays with wavelengths near and inside the water windows (23A-44A) produced by the laser-plasma were absorbed by the specimen and then registered on a photo resist. The x-ray images imprinted on the photo resist were then developed and analyzed with an atomic force microscope (AFM). Mouse thioglycollate-elicited peritoneal macrophages in suspension were examined by this new x-ray microscope. The x-ray images of the macrophages were compared with those observed by conventional transmission electron microscopy (TEM). The x-ray images showed no obvious organelles, including the nucleus and endoplasmic reticulum, as can be seen with TEM, but high- and low-contrast structures caused by mass distribution of carbon were observed. Thus, using the x-ray microscopy we visualized the first x-ray images of macrophage ultrastructures. The successful x-ray imaging of macrophage ultrastructure indicates that proximity x-ray microscopy may be of value in studying physiology linked to the dynamics of a cell.
Kado
M
M
Center for Research and Education in Optics and Lasers, University of Central Florida, Orlando, Florida 32826, USA.
Richardson
M
M
Rajyaguru
J M
JM
Muszynski
M J
MJ
Friedman
H
H
Yamamoto
Y
Y
D000818:Animals; D005260:Female; D007834:Lasers; D017737:Macrophages, Peritoneal / Q000648:ultrastructure*; D051379:Mice; D008807:Mice, Inbred BALB C; D008853:Microscopy / Q000379:methods*; D018625:Microscopy, Atomic Force; D008854:Microscopy, Electron / Q000379:methods