Cell-based microbots induce cell death only in cancer cells of multiple, different cancer types without affecting health cells

Good news! Cancer is history (soon)!

"Microrobots are a promising avenue for delivering medicines in the body ... A similarly tiny workhorse does a better job: our body’s own cells.

Researchers aimed to design a therapeutic that merged the drug delivery abilities of microrobots with the biological hunting abilities of natural cells.

They genetically engineered living human embryonic kidney cells to express a special molecule called tumor necrosis factor–related apoptosis-inducing ligand, or TRAIL.

When TRAIL binds to so-called “death receptors” in cancer cells, it sparks a series of signals that cause the cell to undergo programmed death.

Healthy cells, which have comparatively lower levels of death receptors, get left unharmed.

The researchers then outfitted the TRAIL-modified cells with tiny magnetic beads that enabled the team to magnetically navigate the cells to their targets. Across all kinds of cancer cells the team tested, including colon, brain, kidney, and ovarian cancer cells, the cell-based bot significantly harmed cancerous cells while leaving normal cells alive. ..."

"... These microrobots are built from living human kidney cells and also human fibroblasts that are genetically engineered to produce:

• TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)–a protein that selectively induces cancer cell death.
• GFP (green fluorescent protein)–a fluorescent marker used to visualize and track microrobots during navigation.

The engineered human cells are then attached to magnetic particles—tiny silica beads partially coated with a thin magnetic FePt layer. This design allows the microrobots to be remotely guided using magnetic fields.

After this fabrication process, the human cell-based microrobots can be magnetically controlled and directed toward target locations, where they release TRAIL as a therapeutic agent. Under external magnetic fields, they can be precisely guided to tumor sites, where they accumulate and act locally. ..."

From the abstract:

"Medical microrobots have strong potential for targeted therapeutic delivery; however, current systems achieve only physical targeting, and once at the target site, they are unable to distinguish healthy cells from cancerous ones because of the lack of biological selectivity.

Here, we present a biohybrid microrobot system that combines magnetic targeting with biological selectivity. The microrobots are derived from human embryonic kidney cells genetically engineered to produce tumor necrosis factor–related apoptosis-inducing ligand (TRAIL), a molecule that induces cancer cell death in multiple tumor types without damaging healthy cells.

Engineered cells are then conjugated to biocompatible magnetic Janus particles—silica beads half-coated with FePt nanofilms—to enable external magnetic control. With magnetic fields, the microrobots accumulate around the tumor spheroids and continuously release TRAIL for several days, leading to selective cancer cell death while avoiding damage to healthy cells.

This study combines microrobotics with genetically engineered cell therapies to achieve a targeted, prolonged, and cancer-selective therapeutic delivery."

ScienceAdviser

Human cell-based microrobots selectively kill cancer cells without harming healthy tissues

Genetically engineered human cell–based microrobots for selective cancer cell death (open access)

Figure 1. Fabrication of human cell-based microrobots.

Researchers create world's smallest programmable, autonomous microrobots at submillimeter dimensions

Amazing stuff! Not all robots are humanoid! 😊

"... Barely visible to the naked eye, each robot measures about 200 by 300 by 50 micrometers, smaller than a grain of salt. Operating at the scale of many biological microorganisms, the robots could advance medicine by monitoring the health of individual cells and manufacturing by helping construct microscale devices.

Powered by light, the robots carry microscopic computers and can be programmed to move in complex patterns, sense local temperatures and adjust their paths accordingly. ..."

From the abstract 1 (emphasis added):

"Although miniaturization has been a goal in robotics for nearly 40 years, roboticists have struggled to access submillimeter dimensions without making sacrifices to onboard information processing because of the unique physics of the microscale. Consequently, microrobots often lack the key features that distinguish their macroscopic cousins from other machines, namely, on-robot systems for decision-making, sensing, feedback, and programmable computation.

Here, we take up the challenge of building a robot comparable in size to a single-celled paramecium that can sense, think, and act using onboard systems for computation, sensing, memory, locomotion, and communication.

Built massively in parallel with fully lithographic processing, these microrobots can execute digitally defined algorithms and autonomously change behavior in response to their surroundings.

Combined, these results pave the way for general-purpose microrobots that can be programmed many times in a simple setup and can work together to carry out tasks without supervision in uncertain environments."

From the significance and abstract 2 (emphasis added):

"Significance

Electrokinetic propulsion offers speed, simplicity, and reliable operation at the microscale, but, despite decades of research, current micromotors cannot incorporate on-board systems for sensing and information processing, limiting their usefulness.
Here, we point a way forward by demonstrating electrokinetic microrobots whose propulsion is directly controlled by onboard electronics, namely photovoltaic cells.

Although incorporation of complex circuits is reserved for future work, these initial demonstrations simplify design and control of electrokinetic microrobots, decoupling the chemical environment from the propulsive electric field, and operate in new environments like those with high conductivities or that lack specialized fuels. Long term, these actuators could enable fast, robust sub-millimeter robots that use onboard electronics to sense, think, and act all on their own.

Abstract

Semiconductor microelectronics are emerging as a powerful tool for building smart, autonomous sub-millimeter robots.

Yet a number of existing microrobot platforms, despite significant advantages in speed, robustness, power consumption, or ease of fabrication, have no clear path toward electronics integration, limiting their potential for intelligence.

Here, we show how to upgrade a class of self-propelled particles into electronically integrated microrobots, reaping the best of both platforms in a single design.

Inspired by electrokinetic micromotors, these robots generate electric fields in a surrounding fluid, and by extension propulsive electrokinetic flows.

The underlying physics is captured by a model in which robot speed is proportional to applied current, making design and control straightforward.

As proof, we build basic robots at the 100-micron scale that use rudimentary, on-board photovoltaic circuits and a closed-loop optical control scheme to navigate waypoints and move in coordinated swarms at speeds of up to one body length per second.

Broadly, the unification of micromotor propulsion with on-robot electronics invites future work to realize robust, fast, easy to manufacture, electronically programmable microrobots that remain operationally viable for months to years."

Researchers create world's smallest programmable, autonomous robots

Microscopic robots that sense, think, act, and compute (open access, 1)

Electrokinetic propulsion for electronically integrated microscopic robots (open access, 2)

Fig. 1 Fig. 1. Overview of the microrobot circuits.

Fig. 1 Electrokinetic propulsion for microrobots.