epithelial cells
Sperm cells can be selectively captured using a clinical procedure known as laser capture microdissection (LCM), which is commonly used to select tumor cells from surrounding tissue on microscope slides. Sperm cells from sexual assault evidence spread on microscope slides can be collected with LCM to perform reliable STR testing. When sperm cells are observed in the field of view of the microscope, a tiny laser is activated, and a thin plastic fi lm placed over the slide melts at the specifi c point of laser light contact to capture or embalm the cell of interest. By moving the microscope slide around, dozens of sperm cells are collected onto this thin fi lm that sits directly above the sample. The collection fi lm is then transferred to a tube where DNA from the isolated sperm can be extracted and amplified using the polymerase chain reaction. Other LCM methods catapult identified cells directly into a collection tube.
Sources
Anslinger , K. , et al. ( 2007 ) . Sex-specific fl labeling and laser capture microdissection of male cells . International Journal of Legal Medical , 121 , 54 – 56 . Elliott , K. , et al. ( 2003 ) . Use of laser microdissection greatly improves the recovery of DNA from sperm on microscope slides . Forensic Science International , 137 , 28 – 36 . Sanders , C. T. , et al. ( 2006 ) . Laser microdissection separation of pure spermatozoa from epithelial cells for short tandem repeat analysis . Journal of Forensic Sciences , 51 , 748 – 757 .
epithelial cells