[Abstract]  [Full Text]  [PDF]

Neora Pick¹, Scott Cameron¹, Dorit Arad¹ and Yossef Av-Gay^1*

¹ University of British Columbia, Department of Medicine, Division of Infectious Diseases. Vancouver, BC, V5Z 3J5. Canada.

* To whom correspondence should be addressed: Yossef Av-Gay, University of British Columbia, Department of Medicine, Division of Infectious Diseases. 2733 Heather Street, D450 HP East, Vancouver, BC, V5Z 3J5. Canada. Phone: 604-875-4588. Email: yossi@interchange.ubc.ca

Biol. Proced. Online 2004;6:220-225. doi:10.1251/bpo92
Submitted: February 25, 2004; Accepted: September 19, 2004; Published: October 01, 2004.

Indexing terms: Flow cytometry; Propidium; Lethal Dose 50.

Abbreviations: FACS, Fluorescence Activated Cell Sorting; PI, propidium iodide; LD50, lethal dose in which 50% of the cells die.

The worldwide rapid increase in bacterial resistance to numerous antibiotics requires on-going development of new drugs to enter the market. As the development of new antibiotics is lengthy and costly, early monitoring of compound's toxicity is essential in the development of novel agents. Our interest is in a rapid, simple, high throughput screening method to assess cytotoxicity induced by potential agents. Some intracellular pathogens, such as Mycobacterium tuberculosis primary site of infection is human alveolar macrophages. Thus, evaluation of candidate drugs for macrophage toxicity is crucial. Protocols for high throughput drug toxicity screening of macrophages using flow cytometry are lacking in the literature. For this application we modified a preexisting technique, propidium iodide (PI) exclusion staining and utilized it for rapid toxicity tests. Samples were prepared in 96 well plates and analyzed by flow cytometry, which allowed for rapid, inexpensive and precise assessment of compound's toxicity associated with cell death.