Microinjection of living adherent cells by using a semi-automatic microinjection system

Area of Science:

• Biotechnology
• Cell Biology
• In Vitro Testing

Background:

• In vitro testing offers an alternative to animal experimentation.
• Capillary pressure microinjection is a key technology for delivering large molecules into single living cells.
• Improving cell survival rates post-microinjection is crucial for advancing in vitro research.

Purpose of the Study:

• To develop and present a reliable three-phase evaluation process for assessing cell survival after capillary pressure microinjection.
• To report initial results from a semi-automatic capillary pressure microinjection system.
• To optimize microinjection techniques for increased cell viability.

Main Methods:

• A three-phase evaluation process was developed: cell membrane penetration, substance delivery, and post-injection cell survival.
• A semi-automatic capillary pressure microinjection system was utilized.
• Experiments were conducted on retinal pigment epithelial cells, MCF-7 human breast cancer cells, and SH-SY5Y neuroblastoma cells.

Main Results:

• The micromanipulator achieved an average cell membrane penetration success rate of 87%.
• Initial injection tests demonstrated a 49% success rate for delivering fluorescein dextran into MCF-7 cells.
• Post-microinjection survival tests with KCl in neuronal cells showed initial decreased adhesion followed by recovery and dendrite growth.

Conclusions:

• The presented three-phase evaluation method provides a framework for assessing capillary pressure microinjection efficiency.
• The semi-automatic system shows potential for reliable in vitro cell manipulation.
• Further studies are required to obtain statistically significant cell survival rates and optimize the technique.