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 endoplasmic reticulum in human cell line U-2 OS (HPA003901)
Scale bar represents 10µm
The endoplasmic reticulum is connected to the outer of the two nuclear membranes and consists of a series of interconnected membranes. It is usually divided into two parts: the smooth (sER) and the rough endoplasmic reticulum (rER), the latter being located closest to the nucleus. The rER has ribosomes attached to its cytoplasmic surface and is responsible for protein synthesis. The sER is involved in lipid and steroid synthesis. Lipids and correctly folded and assembled proteins are sent on to the Golgi apparatus for further processing and sorting. Another important task of the endoplasmic reticulum is the uptake and storage of calcium ions from the cytoplasm, as such will be released from the ER upon the receipt of certain extracellular signals.
As the endoplasmic reticulum is consistent with the outer nuclear membrane, it is recognizable by a network-like staining of the cytoplasm and staining of the nuclear membrane. It is usually stronger close to the nucleus and weakens as it gets closer to the edges of the cell. The structure is a network of thin strands that intersect at regular intervals.