Tsinghua University develops microscope that overcomes imaging limits, elucidates electroacupuncture’s immunomodulatory mechanism

Chinese researchers have developed an ultrahigh-resolution microscope that can observe the collective behavior of immune cells in real time in living organisms, using it to elucidate the immunomodulatory mechanism of electroacupuncture for the first time worldwide.

A joint research team led by Professors Dai Chonghai and Wu Jiamin of Tsinghua University and Professor Wang Wei of Huazhong University of Science and Technology published a research paper detailing the findings in the international journal Nature Biotechnology on the 15th (local time), Chinese biotechnology media outlet BioOn reported on the 31st.

The research team developed a new confocal volumetric microscope named “RUSH3D-HR.” The microscope overcomes the trade-off among spatial resolution, field of view, imaging speed and sample viability—considered limitations of existing technologies—a so-called “impossible triangle.”

RUSH3D-HR achieves a high numerical aperture (NA) of 1.05 and can capture a broad volume measuring 2.7 × 2.0 × 0.04 mm³ five times per second at a high resolution of approximately 390 nanometers (nm). This performance increases experimental efficiency by more than several dozen times compared with conventional microscopes.

Using the technology, the research team observed the movement of more than 6,000 neutrophils in the spleens of mice in which inflammation had been induced with lipopolysaccharide (LPS) for more than one hour. The researchers discovered “burst collective behavior,” in which neutrophils that had been randomly dispersed suddenly gathered.

In particular, the team directly confirmed that this collective behavior by neutrophils was suppressed when electroacupuncture stimulation was applied to Zusanli (ST36), one of the acupuncture points. This provided direct evidence that peripheral nerve stimulation can regulate the immune system.

The research team explained, “RUSH3D-HR technology successfully enabled us to observe various immune phenomena at the subcellular level, including cell migration during wound healing and neutrophil-macrophage interactions in acute liver failure.”

The findings suggest that RUSH3D-HR technology could be broadly used across fields including cell biology, immunology and pathology to understand disease progression.