Detection and spatial distribution of the beta 2 integrin (Mac-1) and L-selectin (LECAM-1) adherence receptors on human neutrophils by high-resolution field emission SEM.

1993 ◽  
Vol 41 (3) ◽  
pp. 327-333 ◽  
Author(s):  
S L Erlandsen ◽  
S R Hasslen ◽  
R D Nelson
Keyword(s):  
Cell Adhesion ◽  
High Resolution ◽  
Field Emission ◽  
Cell Body ◽  
Human Neutrophils ◽  
Adhesion Receptors ◽  
Backscatter Electron Imaging ◽  
Beta 2 ◽  
Electron Imaging ◽  
Small Clusters

We have developed a method utilizing high-resolution field emission SEM and backscatter electron imaging of immunogold for detection of cell adhesion receptors on the surface of unfixed human neutrophils, using indirect immunogold localization of specific murine monoclonal antibodies (MAb) to the cell adhesion receptors L-selectin (LECAM-1) and the beta 2 integrin (Mac-1). We have observed that these two receptor populations occupy different membrane domains on the surface of unactivated human neutrophils. LECAM-1 was observed to occur in clusters on the tips of microvilli or membrane ruffles and was seldom detected on the membrane of the cell body. On the other hand, Mac-1 was found mainly on the membrane of the cell body in unactivated neutrophils, either singly or in small clusters, and was only rarely encountered on microvilli or ruffles. In contrast, the distribution of Mac-1 on activated, spreading neutrophils was markedly increased (up-regulated) and occurred in clusters on both the membrane of the cell body and also of surface projections, i.e., microvilli and ruffles. The unique distributions of LECAM-1 and Mac-1 on the surface of unactivated human neutrophils, as observed by high-resolution LVSEM, confirm the spatial relationships of these receptor types as predicted by models for the attachment of circulating neutrophils to vascular endothelium and their emigration to sites of inflammation.

High-resolution backscatter electron imaging of colloidal gold in LVSEM

2003 ◽  
Vol 211 (3) ◽  
pp. 212-218 ◽  
Author(s):  
S. Erlandsen ◽  
Y. Chen ◽  
C. Frethem ◽  
J. Detry ◽  
C. Wells
Keyword(s):  
High Resolution ◽  
Colloidal Gold ◽  
Backscatter Electron ◽  
Backscatter Electron Imaging ◽  
Electron Imaging

scholarly journals Etching and High-Resolution Backscatter Electron Imaging for Semi-Automated Segmentation and Stereology of the Gamma Prime Phase in Ni-based Superalloys

2010 ◽  
Vol 16 (S2) ◽  
pp. 682-683
Author(s):  
EJ Payton ◽  
PJ Phillips ◽  
MJ Mills
Keyword(s):  
High Resolution ◽  
Automated Segmentation ◽  
Backscatter Electron ◽  
Gamma Prime ◽  
Backscatter Electron Imaging ◽  
Electron Imaging ◽  
Prime Phase

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Digital image acquisition for the Hitachi S-900 field-emission SEM

1994 ◽  
Vol 52 ◽  
pp. 1034-1035
Author(s):  
S. L. Erlandsen ◽  
P. Telega ◽  
E. Chi ◽  
W. Dobson ◽  
E. Egelman
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Cell Surfaces ◽  
Digital Conversion ◽  
Image Storage ◽  
Macromolecular Assemblies ◽  
Data Translation ◽  
Electron Imaging ◽  
Imaging Conditions ◽  
Frame Grabber

Users of the Hitachi S-900 field emission SEM attempting to do high resolution topographical studies of cell surfaces (or macromolecular assemblies) and correlative localization of colloidal gold probes are handicapped by imaging conditions related to contamination or radiation damage of the specimen surface since secondary (SE) and backscatter (BS) electron imaging must be done consecutively.We have developed a digitial acquisition system for the S-900 FESEM using an analog/digital conversion board on the VME bus of a Silicon Graphics IRIS, using the conventional and graphics memory for image storage, rather than using a frame grabber with its internal A/D and frame memory. A DT-1492-G board from Data Translation with a 250 kHz throughput was used for the 12-bit A/D circuitry. We collect data at 12-bit resolution, and use the frame buffer memory on the IRIS for separately converting, and then displaying as 8-bit (greyscale, 256 levels) SE and BS electron images.

scholarly journals Receptors for the Chemoattractants C5a and IL-8 Are Clustered on the Surface of Human Neutrophils

1997 ◽  
Vol 45 (11) ◽  
pp. 1461-1467 ◽  
Author(s):  
Gary D. Gray ◽  
Sharon R. Hasslen ◽  
Julia A. Ember ◽  
David F. Carney ◽  
Michael J. Herron ◽  
...  
Keyword(s):  
Human Neutrophils ◽  
Backscatter Electron ◽  
Anterior Pole ◽  
New Information ◽  
Activated State ◽  
C5a Receptors ◽  
Blood Neutrophils ◽  
Backscatter Electron Imaging ◽  
Electron Imaging ◽  
Leukocyte Receptors

We have used high-resolution field emission scanning electron microscopy with backscatter electron imaging to detect immunogold-labeled C5a and interleukin-8 (IL-8) receptors on human blood neutrophils. The receptors were labeled with receptor-specific antibodies in combination with secondary antibody conjugated to immunogold. When neutrophils were isolated in a “nonactivated” state, both of these receptor populations were expressed primarily in clusters on nonprojecting domains of the cell membrane. When these cells were double labeled for C5a and IL-8 receptors, intermixing of these receptor species in a common cluster was not found. When neutrophils were isolated in an “activated” state, by mixing the blood with N-formylmethionyl-leucyl-phenylalanine, the cells were seen to be elongated and ruffled at their anterior pole, but the C5a receptors did not disperse or redistribute on the surface of the peptide-activated cells. Analysis of the distribution of human C5a receptors expressed by transfected mouse L-cell fibroblasts showed the C5a receptors to be clustered, but expressed on nonprojecting and projecting domains of the cell surface. These observations provide new information on the topographical expression of leukocyte receptors involved in directing cell migration. (J Histochem Cytochem 45:1461–1467, 1997)

Remarks on the application of backscattered electron imaging (BEI) to the scanning electron microscopy (SEM) of biological structures

1983 ◽  
Vol 41 ◽  
pp. 484-487
Author(s):  
Etienne de Harven
Keyword(s):  
High Resolution ◽  
Incident Beam ◽  
Spot Size ◽  
Primary Electron ◽  
Critical Point Drying ◽  
Cell Shapes ◽  
High Resolution Images ◽  
Backscattered Electron ◽  
Electron Imaging ◽  
Scanning Electron

Biological ultrastructures have been extensively studied with the scanning electron microscope (SEM) for the past 12 years mainly because this instrument offers accurate and reproducible high resolution images of cell shapes, provided the cells are dried in ways which will spare them the damage which would be caused by air drying. This can be achieved by several techniques among which the critical point drying technique of T. Anderson has been, by far, the most reproducibly successful. Many biologists, however, have been interpreting SEM micrographs in terms of an exclusive secondary electron imaging (SEI) process in which the resolution is primarily limited by the spot size of the primary incident beam. in fact, this is not the case since it appears that high resolution, even on uncoated samples, is probably compromised by the emission of secondary electrons of much more complex origin.When an incident primary electron beam interacts with the surface of most biological samples, a large percentage of the electrons penetrate below the surface of the exposed cells.

Field Emission SEM Equipped With Noise Compensator

1973 ◽  
Vol 31 ◽  
pp. 302-303
Author(s):  
S. Saito ◽  
H. Todokoro ◽  
S. Nomura ◽  
T. Komoda
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Field Emission ◽  
Low Contrast ◽  
Probe Current ◽  
High Resolution Images ◽  
Scanning Electron

Field emission scanning electron microscope (FESEM) features extremely high resolution images, and offers many valuable information. But, for a specimen which gives low contrast images, lateral stripes appear in images. These stripes are resulted from signal fluctuations caused by probe current noises. In order to obtain good images without stripes, the fluctuations should be less than 1%, especially for low contrast images. For this purpose, the authors realized a noise compensator, and applied this to the FESEM.Fig. 1 shows an outline of FESEM equipped with a noise compensator. Two apertures are provided gust under the field emission gun.

Development of a conical anode Fe-gun for low voltage SEM

1988 ◽  
Vol 46 ◽  
pp. 978-979
Author(s):  
T. Miyokawa ◽  
S. Norioka ◽  
S. Goto
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Low Voltage ◽  
Irradiation Damage ◽  
Cold Cathode ◽  
Virtual Source ◽  
Source Position ◽  
Electrostatic Lens ◽  
Electrostatic Lenses ◽  
Wide Range

Field emission SEMs (FE-SEMs) are becoming popular due to their high resolution needs. In the field of semiconductor product, it is demanded to use the low accelerating voltage FE-SEM to avoid the electron irradiation damage and the electron charging up on samples. However the accelerating voltage of usual SEM with FE-gun is limited until 1 kV, which is not enough small for the present demands, because the virtual source goes far from the tip in lower accelerating voltages. This virtual source position depends on the shape of the electrostatic lens. So, we investigated several types of electrostatic lenses to be applicable to the lower accelerating voltage. In the result, it is found a field emission gun with a conical anode is effectively applied for a wide range of low accelerating voltages.A field emission gun usually consists of a field emission tip (cold cathode) and the Butler type electrostatic lens.

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