On the welcome page of the dictionary, three major sections are shown: Normal tissues, Cancer and Cell structure. Below the image of each section are links to introductory texts for i) normal tissue histology, ii) hallmarks of cancer, and iii) cell structure overview. For the cancer-section there is also a link to current cancer statistics (incidence, survival, etc) for Sweden and the rest of the world. Within each section there are direct links to histology descriptions of different tissue types and tumor forms as well as descriptions of cell structures.
For the 'Tissue & cell types' and 'Tumor' sections, tissue-slides stained with hematoxylin and eosin (HE) are shown at three different levels of magnification. On the top level, an overview of the whole tissue-sample is shown with boxes in black indicating where zoomed-in representative parts of the tissue are available for viewing. Clicking on these boxes will zoom in on that part to show tissue structures, cells and features in greater detail. Throughout these sections, arrows indicate relevant tissue structures, cell-types and other features.
For the 'Cell structure' section, immunofluorescent images of formaldehyde-fixed cell lines are shown. The various cell structures that are demonstrated are always shown in the green channel using an antibody found in the Human Protein Atlas. The antibody name is linked to the subcellular location summary page of the target gene. The other channels: nucleus, microtubules and endoplasmic reticulum, are always shown in the blue, red and yellow channels, respectively. The channels can be toggled on and off by clicking on the respective coloured button above the image. When applicable, the immunofluorescent images are complemented by immunohistochemically stained cells where the location of the particular cell structure is shown in brown.
A common feature for all sections is that a general descriptive text about the tissue, tumor-type or cell structure is provided when browsing a particular topic.
Staining of microtubules in human cell line RT-4 (HPA017750)
Scale bar represents 10?m
Cytoskeleton - microtubules
Microtubules function as a rail network, transporting vesicles to different locations within the cell. They start out from the microtubule organizing centre (MTOC) at the centrosome and stretch out to the edges of the cell. At high enough concentrations of the tubuli subunits, the microtubules will spontaneously self assemble, and when the concentration dips they will disassemble. This process of dynamic instability is much faster at the free ends of the tubules, thus referred to as the plus ends, whereas the slowly changing minus ends are joined together at the MTOC.
During mitosis the microtubule network will completely disassemble and instead form what will become the mitotic spindle, responsible for separating the duplicated chromosomes into the two daughter cells.
Immunofluorescent staining
Immunofluorescent staining of microtubules shows thin strands that stretch throughout the whole cell. It is almost always possible to detect the center from which they all originate, the centrosome, even though it need not be stained.
Sometimes it is also possible to stain the growing plus ends of the microtubule, in which case only the tip furthest away from the center is stained.