{"id":173,"date":"2025-05-27T08:54:04","date_gmt":"2025-05-27T15:54:04","guid":{"rendered":"https:\/\/scienceblog.com\/sciencechina\/?p=173"},"modified":"2025-05-27T08:54:04","modified_gmt":"2025-05-27T15:54:04","slug":"scientists-turn-immune-cells-into-light-controlled-robots","status":"publish","type":"post","link":"https:\/\/scienceblog.com\/sciencechina\/2025\/05\/27\/scientists-turn-immune-cells-into-light-controlled-robots\/","title":{"rendered":"Scientists Turn Immune Cells Into Light-Controlled Robots"},"content":{"rendered":"

Chinese researchers have developed a new type of microrobot that transforms ordinary immune cells into precision-guided warriors using nothing more than focused light beams.<\/p>\n

The “phagobots”\u2014macrophage cells that can be awakened and steered with near-infrared laser light\u2014represent a major advance in biomedical robotics by combining the natural power of immune cells with robotic controllability. Published in Light: Science & Applications<\/a>, the research demonstrates how these light-powered immune microrobots can hunt down and destroy various threats including bacteria, cancer debris, and plastic nanoparticles both in laboratory settings and inside living zebrafish.<\/p>\n

The breakthrough addresses a fundamental challenge in medical robotics: how to create controllable microscopic machines that won’t be rejected by the body’s immune system.<\/p>\n

Waking Up Cellular Warriors<\/h2>\n

“We wanted to find a way to control immune cells with the same precision as machines, but without taking away their natural strengths,” said Professor Hongbao Xin from Jinan University, the study’s corresponding author. “With this dual-mode optical control strategy, macrophages remain completely natural, yet they can be precisely instructed to move, seek, and phagocytosis of bio-threats both in vitro and in vivo.”<\/p>\n

The process begins by focusing a tightly controlled near-infrared laser beam onto resting macrophages\u2014the immune system’s natural cleanup crew. Within minutes, the localized heating effect triggers temperature-sensitive ion channels in the cell membrane, causing calcium to flood into the cell.<\/p>\n

This calcium surge activates the cell’s energy production and leads to a burst of reactive oxygen species, transforming the dormant macrophage into an active predator complete with flexible “arms” called pseudopodia.<\/p>\n

Light-Guided Precision Navigation<\/h2>\n

“It’s like flipping a biological switch with light,” said Xing Li, the paper’s first author and PhD student at Jinan University. “The light doesn’t just move the cell. It turns the cell into a warrior.”<\/p>\n

Once activated, the researchers can control the phagobot’s movement by manipulating its extended pseudopodia with gentle optical forces. Unlike other bio-microrobots that push entire cells around using magnetic or acoustic fields, this approach works at the subcellular level.<\/p>\n

“Other bio-microrobots that rely on magnetic or acoustic fields to push entire cells, which may inevitably disturb cell activity and immune state. On contrast, this method works at the subcellular level, guiding only the pseudopodia,” explained co-corresponding author Associate Professor Ting Pan. “This keeps the rest of the cell undisturbed, mimicking how immune cells naturally migrate in tissue.”<\/p>\n

Hunting Down Multiple Threats<\/h2>\n

Laboratory tests revealed the phagobots’ remarkable versatility in targeting different biological threats. The controlled immune cells successfully engulfed Staphylococcus aureus bacteria, yeast cells, plastic nanoparticles, and tumor cell debris with impressive precision.<\/p>\n

The speed of engulfment depended on target size\u2014smaller particles like bacteria took about 2 minutes to consume, while larger targets like yeast cells required around 10 minutes. In one demonstration, researchers programmed a single phagobot to sequentially hunt down and destroy six different bacterial cells within 10 minutes.<\/p>\n

Key Capabilities Demonstrated:<\/h3>\n