Neisseria meningitidis and Neisseria gonorrhoeae are obligate pathogens of the human host. Due to their adaptation to the human host, many factors required for infection are specialized for the human host to the point that natural infection processes are difficult to replicate in animal models. Immortalized human cell lines have been used to identify the host factors necessary for successful colonization of human mucosal surfaces. One such model is the Detroit 562 pharyngeal immortalized cell monolayer model which is used to measure the rate of attachment to and invasion of N. meningitidis and N. gonorrhoeae into epithelial cells. The methodology of this assay, as well as the maintenance of Detroit 562 cells necessary for the experiment, will be described.