Geoffrey Coombs

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.

Methicillin resistance, in particular hetero-methicillin resistance, in S aureus and the coagulase negative staphylococci (CNS) can be difficult to detect by phenotypic methods. Subsequently detection of the mecA gene for determining methicillin resistance in staphylococci is generally considered to be the Gold Standard. In Australian diagnostic microbiology laboratories, molecular assays used for the detection of the mecA gene have generally been designed in-house. These assays have either been single primer PCR assays targeting the mecA gene or a duplex primer PCR assay with primers targeting the mecA gene and a gene specific for S. aureus such as the nuc (nuclease) or fem gene. In some laboratories a Panton Valentine-leukocidin (PVL) gene primer has been incorporated with the duplex PCR assay allowing the detection of PVL virulence genes in S aureus.