Leukocyte Intravascular Crawling Through Intravital Microscopy ( Ivm )

outside of a living organisms. Though not as effective as in-vivo studies, the living cells of a

51) What activity does cell 1 undertake to contribute to the body's defense against injury and infection? phagocytosis of foreign materials

Neutrophils and wandering macrophages (originating form monocytes) were most likely the WBCs that phagocytized the tissues and pathogens early in Ed's infection. They gather at sites of infection or inflammation by means of emigration. They are

IgA – antibodies that are secreted across mucus layer to prevent microbes from penetrating cell bodies

To make the specimen compatible with both forms of advanced microscopy, they sufficiently prepared samples by coupling the specimen with a fluorescence that was also conductive. This technique was accomplished with the FlouroNanogold label, which contains gold nanoparticles covalently bonded to a fluorescence label. That way, the LM worked as well as the EM for the same set of kinetochores that were being studied. The Hec1 protein was stained in this case because this protein naturally delineates the structures to be studied.

Numerous cells have little, finger-formed projections of the plasma film on their uncovered surfaces. These projections, called microvilli (solitary, microvillus), significantly increment the surface territory of the phone presented to the extracellular environment. Likewise, they cover the surfaces of cells that are effectively engrossing materials from the extracellular liquid, for example, the cells coating the stomach related tract. Microvilli have broad associations with the cytoskeleton. A center of small scale fibers hardens each microvillus and grapples it to the cytoskeleton at the terminal web.

Using the microscope provided to analyze the different size of the different cells and organisms

Lymph is the name given to the fluid of plasma proteins that escape the circulatory system at the sites of the capillary network and diffuse into the cells around the capillaries. To enable the body to maintain a homeostatic fluid level and pressure, the lymph must be returned to the circulatory system. The way this happens is for the the network of lymph vessels to pick up the fluid which has escaped,

N-cadherin is a protein encoded by the CDH2 gene. It interacts with the cellular cytoskeleton, and is often involved in cardiac muscle, as well as certain cancers. Being calcium dependent, it helps to maintain cellular structure and integrity. For example, it plays a role in trans-endothelial migration, which involves cell-cell adhesion [3]. The endothelial layer contains many different fibers, as well as pathways that allow attachment for the cadherin protein. Some cancer cells can eventually pass through the endothelium, causing the cancer to become malignant and spread. Cadherins in this case can be used to identify and track the spread of the cells, and further identify common routes of travel through the human vasculature.

The next two molecules, α6β4 integrin, and collagen XVII extend beyond the basal keratinocyte membrane and into the lamina lucida layer of the basement membrane zone and hence they are known as transmembrane molecules. These latter two molecules can be found within the outer plaque of the hemidesmosome. The last molecule, CD151, the most recently discovered molecule, is closely associated with α6β4 Integrin, and resides at or near the surface of the basal cell plasma membrane. The intermediate filaments attach to BPAG1 and plectin, which compose the hemidesmosome inner plaque. Both plectin and BPAG1 belong to the plakin family of proteins, and share significant sequence homology.[14]

The ways we can examine organism is by using a microscope. We’ve used a bright-Field microscopy that shines light through a specimen (1). The organism is then magnified as light refracts through the four objective lens 4X, 10X, 40X, and 100X found on the revolving nosepiece. It is then further magnified as we look through the ocular lens at 10X. By multiplying the objective lenses and the ocular lens gives a total magnification of 40X, 100X, 400X and 1000X. Once reaching objective lens 100X oil needs to be put on the slide. By using oil, it increases the lens magnification because oil refracts light just like the lens in the microscope and it has the same refractive index (1).

We used ethanol when we used the crystal violet dye for instance. The ethanol allows the tightening of the peptidoglycan layer, making it parched and devoid of water, which in turn forces the stain to stay within the cell. When this happens, we can observe the cell accordingly under a microscope.

The effects of integrin’s vary from the type of protein they are and how they affect a certain part of the body. They are usually surface receptors that will interact with extracellular matrix. There is a family of alpha and beta classes which would usually form heterodimers. They are used for adhesion purposes most of the time and can also transduce a biochemical signal into or out of the cell. This process is called bidirectional, where the can transmit information from in and out of a cell. There are different structures that integrin’s play a role in. Integrin’s can bind to a ligand, where it will form a complex with a biological molecule that will usually serve as a purpose. They can go through a process called activation, where they would have a conformational change of the receptor. They can also trigger a cascade effect, which can change a receptors shape.

Promoting migration is a major function of Rabs as tumour cells need to be able to invade ECM and migrate to other sites. Rabs, especially Rab25, have roles in trafficking and recycling integrins, which are cell adhesion molecules providing linkage of cells to the ECM (Arnaout, Goodman and Xiong, 2007), to invasion structures to facilitate migration (Recchi, and Seabra, 2012).

Pathogenic L. monocytogenes go through an intracellular life cycle involving early escape from the phagocytic vacuole, rapid intracytoplasmic multiplication, bacterially induced actin-based motility, and direct spread to neighboring cells, in which they reinitiate the cycle. The bacterium is first phagocytosed by these cells and secretes a pore-forming toxin called listeriolysin, which allows the bacterium to escape from the phagosome. All virulent strains of L. monocytogenes synthesize and secrete listeriolysin. Phospholipase A and B are other virulence factors that facilitate escape of L. monocytogenes from the phagosome. Once out of the phagosome L. monocytogenes is capable of rapid division in the cytoplasm, evading the immune response and moving throughout the cytoplasm from cell to cell. L. monocytogenes is well known for its ability to propel itself like a rocket through the cell cytoplasm. This is the result of the bacterium’s ability to polymerize actin filaments at its tail end. Actin is arranged in subunits to form microfilaments that are capable of directing cell movement. L. monocytogenes accomplishes cell motility through a virulence factor called ActA that takes advantage of normal actin polymerization going on in the cell. The ActA protein shares sequence homology with a protein called WASP that is found in virtually all eukaryotic cells. WASP is responsible for recognizing and