Bellwether July 2021

Page 143

ALISIARA HOBBS CAROLINE FEIG LORENA RAMIREZ

Macrophages

Introduction Phagocytosis, a type of endocytosis, is an engulfing process done by phagocytic cells to eliminate invading organisms. An example of a phagocytic cell undergoing this process is a macrophage. A macrophage is a type of white blood cell that identifies, engulfs, and eliminates harmful bacteria, in this case E. coli. Unlike other methods of transportation, such as osmosis and active transport, the particles involved in phagocytosis are too large to be carried across the membrane causing the cell to attach and engulf the particle (Richards, 2017). A method of quantifying the rate of E. coli being phagocytized is using flow cytometry. Flow cytometry is a technique used to measure particular components of given cells (McKinnon, 2018). A sample of cells, suspended in a fluid, is injected into a flow cytometer where they pass through very small channels that align them in a single file as they pass through the detector. In order for E. coli to be read by the machine, it needs to be changed to express glowing fluorescence done in a process called transformation. Transformation occurs when foreign DNA is added to bacteria, ultimately resulting in the uptake and expression of the traits in the DNA (Griffiths, Miller, Suzuki 2013). Plasmids, pieces of DNA encoding for specific traits, are used in the process of transformation. GFP plasmids are proteins that encode for a green fluorescent gene and can be transformed 144


Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.