---
title: Transplanted Insulin Cells Kept Working for 100 Days in Mice With No Anti-Rejection Drugs
description: Rice University bioengineers kept transplanted insulin-producing cells working in diabetic mice for 100 days with no anti-rejection drugs.
author: Darie Nani (Editor-in-Chief)
updated: 2026-08-06T03:17:45.944Z
canonical: https://richhealthmagazine.com/article/islet-transplant-without-immunosuppression-mice-rice
image: https://cdn.nanimediahouse.com/rice-veiseh-lab-islet-capsules-108065.webp
categories: Longevity & Science
content_type: News
region: United States
publication: Rich Health Magazine
schema_type: Article
---

Bioengineers at Rice University have kept transplanted insulin-producing cells alive and working in diabetic mice for up to 100 days without giving the animals any anti-rejection medication. Those drugs are the reason islet transplantation, a procedure that can free some people with type 1 diabetes from insulin injections altogether, is a treatment almost nobody receives. The work is preclinical, tested so far in mice and in a two-animal pilot in monkeys.

## Recipients Must Take Immunosuppressants for as Long as the Islets Work

In type 1 diabetes the immune system destroys the beta cells in the pancreas that make insulin, so the insulin has to come from an injection or a pump instead. Islet transplantation offers a different route. Doctors take islets, the cell clusters that contain those beta cells, from the pancreas of a deceased donor and infuse them through a catheter into a vein carrying blood to the recipient's liver, where they begin producing insulin.

In an [NIH-sponsored Phase 3 trial](https://www.niddk.nih.gov/health-information/diabetes/overview/insulin-medicines-treatments/pancreatic-islet-transplantation), close to 9 in 10 recipients had an A1C below 7 percent, the goal for many people with diabetes, and no episodes of severe hypoglycemia a year after the transplant. About half needed no insulin at all.

The catch is what has to happen afterwards. The transplanted islets survive only while the recipient keeps taking immunosuppressants, and those drugs carry a higher risk of infection and cancer, kidney damage, high blood pressure, and digestive and neurological side effects. Stop taking them and the body rejects the islets. That, together with a shortage of donor pancreases, is why the procedure stays rare. Between 1999 and 2015, 1,086 people worldwide received an islet transplant.

## The Capsule Now Carries a Second Cell That Releases IL-10

One long-standing answer to the drug problem is encapsulation, enclosing the donor islets in a protective shell so the immune system cannot reach them directly. On its own it runs into something else. The body treats the capsule as foreign and coats it in scar tissue, a process called fibrosis, which can eventually suffocate the cells inside.

The Rice design adds a second kind of cell to the capsule alongside the islets. These are retinal pigment epithelial cells, engineered to secrete a signaling protein called a cytokine continuously. After testing several candidates, the team found interleukin-10, or IL-10, worked best at holding the immune response in check. In healthy rodents, IL-10 produced inside the capsule kept it from being walled off and scarred.

Dilrasbonu Vohidova, a doctoral student in bioengineering at Rice and a co-first author on the study, said conventional immunosuppression “can increase the risk of infection, cancer and organ failure”.

> "This work addresses the critical problem of graft rejection without compromising systemic immunity."
> — Dilrasbonu Vohidova, doctoral student in bioengineering at Rice University and co-first author of the study

## Mice Held Normal Blood Sugar for 100 Days

In diabetic mice, human islets implanted together with the IL-10-producing cells showed less fibrosis around the capsule and stayed viable, and the animals held normal blood glucose [4.76 times longer](https://www.biorxiv.org/content/10.1101/2025.10.13.682221v1.full-text) than islets implanted on their own. None of them received systemic immunosuppression.

## The Monkey Study Used Two Animals and Tested Tolerability

The team also implanted the capsules in the abdominal cavity of cynomolgus macaques, healthy animals rather than diabetic ones. One received the IL-10 capsules and one control animal received unmodified capsules. The researchers state that this part of the study was not powered to measure efficacy and was meant to assess whether the capsules are tolerated and worth carrying forward.

## The Team Is Aiming for Human Trials

Rice describes the research as still preclinical. Omid Veiseh, a professor of bioengineering at Rice, a corresponding author on the study and director of the Rice Biotech Launch Pad, said the results show “we may be able to protect implanted ‘living pharmacies’ by working with the immune system instead of against it”, and that with support from Breakthrough T1D “we are pushing this technology further towards clinical trials in the coming years”. He called the work “an important step forward for cell-based therapies”.

The study was also funded by the Advanced Research Projects Agency for Health and the National Institutes of Health. Its other first authors are Boram Kim, a former Rice doctoral student now a postdoctoral researcher at MIT, and Amanda Nash, an assistant professor of bioengineering at Rice. The researchers say the same idea, pairing an implant with cytokine-producing cells rather than suppressing the whole immune system, could eventually apply to other implanted cell therapies, autoimmune conditions and organ transplants.

More on the lab behind the study is at [veisehlab.rice.edu](https://veisehlab.rice.edu/).

## FAQ

**Q: Why do islet transplant recipients need immunosuppressants?**
Without them, the recipient's immune system treats the donor islets as foreign and destroys them. Recipients have to keep taking the drugs for as long as the transplanted islets are meant to keep working.

**Q: What is the FDA-approved islet transplant for type 1 diabetes?**
In 2023 the FDA approved the first cell therapy made from donor islets. It is for adults with type 1 diabetes who cannot manage their blood glucose and keep having episodes of severe hypoglycemia despite intensive treatment.

**Q: How long do transplanted islets keep working?**
In the NIH-sponsored Phase 3 trial, about 7 in 10 recipients still had an A1C below 7 percent with no severe hypoglycemia two years after the transplant, and about 4 in 10 needed no insulin.

**Q: Is there a cure for type 1 diabetes?**
Not yet. Islet transplantation can free some recipients from insulin, but it requires lifelong immunosuppression and donor islets are scarce. The Rice research is an early, animal-stage attempt to remove the immunosuppression requirement, not a treatment available to patients.