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*CIL – Cell Image Library accession number. Please use this to reference an image.

CIL:36721*  Cite 

A mAb, B25-1-3, was raised to antigen Q2 (arbitrary code) to the same set of membranes as mAb 132-F4-G6 labels. This mAb was more reactive on frozen sections. To tell the age of vacuoles, cells were exposed to latex beads for 2.5 minutes and then washed free of the beads (0.5 min) and then chased in bead-free buffer for a known time before fixing. In this image the labeled phagosome is a DV-I as it contained 1.1µm beads that were present in the medium for the 3 minutes before the cells were fixed. Some vesicles in the cytosol are also labeled but there is very little nonspecific label over the general cytosol or the contents of the vacuole. TEM taken 10/24/92 by R. Allen with Zeiss 10A operating at 80kV. Neg. 19,800X. Bar = 0.2µm.

Technical Details

To label membranes inside the cell we used very lightly fixed cells (0.25% glutaraldehyde) that were then rapidly frozen in liquid nitrogen and sectioned later at -100oC. These frozen sections were picked up on drops of methylcellulose and transferred to a Formvar-supported grid. The sections were immunogold labeled (15nm gold) to show the location of the specific antigen inside the cell as well as on the cell surface. Microtome sections prepared at approximately 75nm thickness. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. Additional information available at (

Biological Sources
NCBI Organism Classification
Paramecium multimicronucleatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
pre-autophagosomal structure membrane
food vacuole
Biological Context
Biological Process
digestive system process
Richard Allen (University of Hawaii)
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Image Type
transmission electron microscopy (TEM)
illumination by electrons
Image Mode
detection of electrons
Parameters Imaged
electron density
intrinsic mass distribution
Source of Contrast
stain with broad specificity
Visualization Methods
stain with broad specificity
uranyl salt
Processing History
recorded image
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Sample Preparation
glutaraldehyde fixed tissue
tissue in vitreous ice embedment
microtome-sectioned tissue
monoclonal antibodies
Relation To Intact Cell
microtome-sectioned tissue
Spatial Axis Image Size Pixel Size
X 2280px ——
Y 2748px ——