Posted in | Microscopy

High Resolution Microscopy Reveals Selective Responses of Human Immune System

A research team at the Sandia National Laboratories in Albuquerque has revealed the power of a high-resolution microscopy technique named Stochastic Optical Reconstruction Microscopy (STORM) that can capture multiple molecules in living immune cells at the same time.

The team presented a paper recently at the 55th Annual Biophysical Society Annual Meeting held in Baltimore. Jesse Aaron and JerilynTimlin deployed this methodology to show the changes in certain protein concentration present in the membranes of the human immune cells that come in contact with toxins from E.coli. The team revealed that the same changes did not take place in the immune cells coming into contact with toxins from Y.pestis, which are the bacteria causing plague.

This research reveals how our immune system can withstand some bacteria, such as E.coli, but not the plague causing bacteria. The team captured the buildup of TLR4, a human receptor protein, which is present on the outside of immune cells as they hunt for foreign bacteria. These receptors identify lipopolysaccharide (LPS), a toxic chemical signifying the presence of some bacteria, and the TLR4 proteins act as mediators of our innate immunity to these infections.

According to Jerilyn Timlin, principal scientist at Sandia National Laboratories, a cell membrane is a complicated, heterogeneous system that consists of proteins that interact with each other simultaneously on a scale much below the diffraction limit. The simultaneous STORM –based dual-color imaging system and an objective-based TIRF microscope and filter-based image splitter, has revealed how the TLR4 receptor is formed after it comes in contact with toxic bacterial LPS.

Resolving these interactions at or below 40nm showed that TLR4 receptors club together when they encounter the toxin. When TLR4 receptors detect toxins emitted by E.coli, they multiply in number and form clusters on the cell membrane.


Tell Us What You Think

Do you have a review, update or anything you would like to add to this news story?

Leave your feedback