Evaluating the effects of immunotoxicants using carbon fiber microelectrode amperometry

Area of Science:

• Immunotoxicology
• Cellular Biology
• Analytical Chemistry

Background:

• Assessing immunotoxicant effects on cellular function is crucial for understanding health risks.
• Single-cell analysis provides detailed insights into cellular processes like exocytosis.
• Mouse peritoneal mast cells (MPMCs) are key players in immune responses and exocytosis.

Purpose of the Study:

• To evaluate carbon fiber microelectrode amperometry (CFMA) as a technique for studying single-cell exocytosis.
• To investigate the impact of immunotoxicants mono-2-ethylhexyl phthalate (MEHP) and bisphenol A (BPA) on MPMC exocytosis.
• To quantify serotonin release and assess exocytotic efficiency in response to MEHP and BPA exposure.

Main Methods:

• Utilized a co-culture model of mouse peritoneal mast cells (MPMCs) and fibroblasts.
• Exposed MPMCs to varying concentrations (10-100 μM) of MEHP and BPA.
• Employed carbon fiber microelectrode amperometry (CFMA) to measure serotonin release from single cells.

Main Results:

• A significant decrease in quantal serotonin content was observed with all tested concentrations of both MEHP and BPA.
• Bisphenol A (BPA) impaired the overall exocytotic efficiency of MPMCs at all exposure levels.
• Mono-2-ethylhexyl phthalate (MEHP) impaired exocytotic efficiency only at the lowest exposure concentration.

Conclusions:

• Carbon fiber microelectrode amperometry (CFMA) is a valuable tool for quantitative analysis in in vitro immunotoxicology.
• MEHP and BPA demonstrably impair single-cell exocytosis function in mouse mast cells.
• CFMA provides biophysical and chemical information essential for understanding immunotoxicant mechanisms at the cellular level.