Morphologic observation of the phagocytic activity of cells and silicosis occurrence in experiments
Morphologic observation of the phagocytic activity of cells and silicosis occurrence in experiments
This experimental method was obtained from the official website of Chongqing Medical University
Operation method
Morphologic observation of the phagocytic activity of cells and silicosis occurrence in experiments
Principle
In higher animals, there exists a phagocytic cell system with defense function, in which granulocytes and monocytes have the strongest phagocytic ability, so it is called phagocytosis, and these cells gradually evolve into macrophages after entering into the tissues with the blood. When the body is invaded by a foreign body, macrophages move toward the foreign body under the action of chemokines, and then extend pseudopods to wrap the foreign body, swallow the foreign body into the cell to form phagocytic vesicles, merge with lysosomes to form secondary lysosomes, and then digest and decompose the foreign body through the acidic hydrolases in the lysosomes. It is currently believed that macrophages within the alveoli play a key role in the pathogenesis of silicosis. When SiO2 silica dust particles are inhaled into the lungs, they are phagocytosed by macrophages in the alveoli, forming phagocytic vesicles, which merge with lysosomes to form secondary lysosomes. As SiO2 is contained in silica dust particles, the hydroxyl groups on its surface form hydrogen bonds with phospholipids or proteins in lysosomal membranes, which changes the stability of the lysosomal membranes, causes lysosomal membranes to disintegrate, and releases hydrolases, which finally leads to the dissolution of the macrophages and their death, And containing SiO2 silica dust particles released, again phagocytosed by other macrophages, and so on repeatedly. Macrophages die in large numbers, and the fibrogenic factors released during their death activate fibroblasts, leading to collagen fiber proliferation. At the same time, the silica released when macrophages die can also be used as an antigen to stimulate immunologically active cells and produce antibodies, and the antigen-antibody reaction produces complexes together with complement, which are deposited on the collagen fibers, giving the newly formed connective tissue a hyaline-like appearance.
Materials and Instruments
Rooster venous blood Adult mice Move 1, Two days before the experiment, 1 ml of 6% starch broth (to act as a marker) was injected intraperitoneally into mice every day to induce the production of more macrophages in the peritoneal cavity. Common Problems 1. Alsever's solution: glucose 2.05 g, sodium citrate 0.80 g, NaCl 0.42 g, dissolved in 100 ml of double-distilled water. For more product details, please visit Aladdin Scientific website.
Alsever's solution Saline Starch broth
Microscope Syringe Carrier plate Cover plate
2, During the experiment, every four students took one mouse treated as above and injected 1ml of 1% chicken blood cell suspension intraperitoneally.
3, After 30 min, 0.5 ml of mouse saline was then injected into the peritoneal cavity.
4、 After 30min, the mice were executed by cervical dislocation method.
5、Take the drop piece of intraperitoneal fluid with a syringe and cover the cover piece.
6、Microscopic observation
2. 6% starch broth: beef paste 0.3g peptone 1.0g NaCl 0.3g Trypan blue 0.3g.
3. Distilled water: 100ml, boil and sterilize, store in 4℃ refrigerator.
4. mouse saline 0.85g sodium chloride dissolved in 100m1 distilled water
5. chicken saline 0.75g sodium chloride dissolved in 100m1 distilled water
6. 1% chicken erythrocyte suspension from the healthy chicken wing vein blood collection or from the market to kill chickens at the blood 2ml (to prevent contamination), put into a bottle containing 8ml AlseVer solution, mixing in the refrigerator at 4 ℃ to save spare (within a week to use). Before use, add 0.85% saline centrifugation (1,500r/min 10min) to wash for two times, and then use saline to form 1% concentration suspension.