Cell Culture

By: Leslie Nelson

Purpose

The objective of the research is to study cytotoxicity to RAW 264.7 mouse macrophages of Echinacea ethanol extract fractions and Lipopolysaccharides (LPS).

Importance

As studies have shown that Echinacea has the antiviral and anti-inflammatory properties, it has become a common medicinal plant in the market. In the past, Native Americans had many medicinal purposes of Echinacea that ranged from treating infected wounds, common colds, burns and immune dysfunction. The RAW 264.7 mouse macrophage cell line has been used to demonstrate that Echinacea extracts and fractions contributes anti-inflammatory activity. Specifically, our lab studied two major inflammation mediators, prostaglandin E2 (PGE2) and nitric oxide (NO), as endpoints for LPS induced inflammation in RAW 264.7 cell culture. When active plant materials were applied to cell culture simultaneously with LPS, the mediator release was significantly alleviated, thus suggesting potential anti-inflammatory activity. Nonetheless, the cytotoxcity of extracts might be a possible cause of the decrease in NO and PGE2. For this reason, cytotoxcity assay on the Echinacea extracts and fractions is necessary to verify there is no decrease in cell viability. In addition, LPS induction could also jeopardize cell viability, which is worthy of investigation.
The importance of cytotoxicity to the studies of botanical impacts on LPS induced inflammation is to help validate results of bioactivity assays by proving cytotoxicity is not the cause of reduced inflammatory response observed in cells treated with plant materials and LPS.

Leslie's role

Under the guidance of Dr. Birt and her graduate students she is performing cell culture and learning the process of conducting the experiment of cytotoxicity assay. Her duties include changing cell media, cell passaging and eventually conducting cytotoxcity assay under supervision. Following the experiments, she will conduct statistical analysis to evaluate cell viability under Echinacea fractions and LPS treatment.

Hypothesis

There is no significant cytotoxicity from Echinacea fractions and LPS at the concentrations used in bioactivity assays.

Results