Plaque assays have traditionally been a reliable way to determine the titer of a lytic virus. However, this method has several shortcomings in that it is time-consuming, labor intensive, and suffers from limited sensitivity. In this article, we describe a novel flow cytometry-based titration assay to quantify green fluorescent protein-labeled herpes simplex virus type 1 (HSV-1-GFP). Using this assay, we were able to directly quantify ten-fold dilutions of the virus in which every GFP-positive cell could be counted. In a head-to-head comparison with a traditional plaque assay, the flow cytometry assay showed a greater linear range and was accomplished in less than half the time of the plaque assay.
Tag: <span>green-fluorescent protein</span>
In October 8, 2008, the Nobel Prize for Chemistry was awarded to Osamu Shimomura, Martin Chalfie, and Roger Tsien ostensibly for the discovery, cloning, and applications of green-fluorescent protein (GFP). This protein is associated with bioluminescence in coelenterates, including jellyfish and sea pansies. This award is as much a celebration of basic research as it is an acknowledgement of the achievements of three accomplished researchers…