🧬 Scientists May Have Found a New Way to Mass-Produce Cancer-Fighting Immune Cells

For more than a decade, cancer immunotherapy has been dominated by T cells. CAR-T therapies can be powerful against some blood cancers, but they remain expensive, highly personalized, and much harder to use against solid tumors.

Now researchers at USC Stem Cell have shifted attention to a different immune lineage: granulocyte-monocyte progenitors, or GMPs — early precursor cells that can produce macrophages, the immune system’s “first responders.”

Macrophages are especially interesting because they naturally enter tumors, engulf abnormal cells, and help coordinate immune responses. But mature macrophages are difficult to grow in large numbers, hard to genetically engineer, and not ideal for freezing and storage.

The USC team worked one step earlier — with GMPs before they mature. Using a defined chemical cocktail, they managed to keep mouse and human GMPs in a progenitor-like state while allowing them to expand long-term in the lab. That is important because long-term self-renewal in the blood system was traditionally associated mainly with true hematopoietic stem cells, not more committed progenitors.

Then the researchers engineered these GMPs with CAR receptors so they could recognize cancer cells. They also added a CAR-Fc design that can recruit other immune cells and help activate broader anti-tumor responses.

In mouse experiments, the engineered GMPs settled into bone marrow and other blood-forming tissues, where they continuously generated tumor-infiltrating macrophages and other myeloid cells. The cells suppressed CD19-positive leukemia and HER2-positive solid tumors, and the dual CAR-Fc design showed stronger effects in allogeneic cancer models.

The same platform also restored antibacterial defense in mice with chronic granulomatous disease, an inherited immune deficiency disorder.

Why this matters: this is not just another CAR-T variant. It is a possible manufacturing breakthrough for an entirely different branch of the immune system — one that may be better suited for solid tumors and potentially easier to produce as an off-the-shelf therapy.

The important caveat: these are still preclinical results in mice. The real test will be whether the platform is safe, durable, and effective in humans.

But the idea is powerful: instead of only engineering mature immune cells, scientists may be learning how to grow a renewable upstream factory that keeps producing cancer-fighting cells from inside the body.

Paper: Cell
https://www.cell.com/cell/fulltext/S0092-8674(26)00643-4

Summary: ScienceDaily
https://www.sciencedaily.com/releases/2026/06/260620100317.htm

#Immunotherapy #Cancer #StemCells #CellTherapy #Biotech

🧠 Scientists Replaced Most of a Mouse’s Cortex With Human Brain Tissue

This sounds like science fiction, but the experiment is real.

Stanford researchers genetically engineered mice so that most of their cerebral cortex and hippocampus never developed. The adult animals were left with only about 2% of the normal amount of corresponding cortical tissue.

Then, shortly after birth, scientists implanted tiny human cortical organoids — brain-like structures grown from human stem cells — into the empty space.

Three months later, more than 90% of the cortical tissue by volume was human-derived.

And it did not simply sit there.

Human neurons became integrated into the mouse nervous system, developed organized electrical activity and sent long-range projections — some extending as far as the spinal cord. The mice retained broadly normal movement, although researchers found specific differences in coordination and spontaneous behavior.

Then came an unexpected discovery.

Inside the transplanted human tissue, researchers found cells resembling von Economo neurons — extremely rare, large neurons associated with brain regions involved in social awareness and decision-making. They occur in humans, great apes, elephants, dolphins and whales, but scientists had never previously succeeded in generating them in laboratory brain cultures.

The team also demonstrated why the model could matter medically. When the animals experienced several hours of reduced oxygen, the human cortical tissue was severely damaged while comparable mouse tissue was largely spared — potentially giving researchers a living model for studying why the developing human brain is particularly vulnerable to oxygen deprivation.

An important distinction: these are not mice with human intelligence or a human brain. The transplanted tissue remained developmentally immature, and the experiment provides no evidence of human-like cognition or consciousness. It is a new animal model for studying human neural development and disease.

But the boundary scientists have crossed is remarkable.

We can now grow substantial amounts of developing human neural tissue not just in a dish —

but inside a living brain, connected to a living nervous system.

Where should the ethical boundary for experiments like this be?

#Neuroscience #Brain #Organoids #StemCells #Biotechnology #Stanford #Science

https://www.nature.com/articles/s41586-026-11032-2