Cells that Evade the Immune System - Warning more Type 1 mouse research

Some interesting progress reported here:


I sure wish I were a mouse. I would have been cured years ago! The following first sentence in the article causes concern:

“Most type 1 diabetics are children and teenagers,” says Salk Professor Ronald Evans, senior author and holder of the March of Dimes Chair in Molecular and Developmental Biology.

I think that has been long dispoven… there are far more Type 1 adults who have been diagnosed with T1 as adults. I thought we had put the misnomer of “juvenile diabetes” to rest. Heartbreaking when children get it, but it is not a disease of mostly children and teenagers.


I don’t think that the professor’s statement that most T1Ds are children and teenagers is true, but I do think it’s true that most T1Ds are diagnosed before adulthood.


I disagree.

The incidence of T1D is highest in children aged 10-14. About a quarter of T1Ds are diagnosed as adults.


Back to the article, I’ve scanned the paper. Of course it’s research in mice again. Dozens of studies concerning protection of islet grafts against the recipient immune systems have been performed. PD-L1 is a known immunosuppressive protein. Another study earlier this year involved linking PD-L1 to islets. It’s nice that this new study has found a way to achieve protection without chemically modifying the surface of islet cells or embedding islets in microgels. Yet it remains to be seen whether this will work well enough to provide long-term islet transplant survival in humans. 50 days transplant survival in a first study in mice is decent, but will it work in longer studies? What percentage of animals will remain free of diabetes and for how long? Will it work in non-human primates and finally humans?
The research was focused mainly on the functioning of the islets, but it doesn’t show how PD-L1 expression prevents immune destruction. Does it prevent islet invasion by cytotoxic T cells and the like? Does it induce regulatory T cells?
The transplantation site and procedure affect islet survival too. These are not the same in mice and in humans. In humans, islet are usually transplanted into the liver via the portal vein. That’s not an option in mice, so the preferred site of islet transplantation is usually under the kidney capsule. Intraportal transplantation is the easiest method and less of a burden to the patient, but a large proportion of the islets doesn’t survive that procedure. That’s a problem. There’s an enormous shortage of donors and multiple donors are needed to treat one patient. I hope the use of induced pluripotent stem cells, as in this paper, can help reduce the shortage of islet grafts.


Thanks for the summary. Good work and of course good questions.


I would like researchers to stop putting questions like this one below in their FAQs. To this day, the best-case scenario has never happened in the quest for a T1D cure. Particularly older generations will remember all the broken promises.

Q: In the best-case scenario, how soon could this treatment be available for humans?

A: We expect that it could take 2-5 years to get FDA approval to use of HILOs in people. Typically, clinical trials of treatments designed for humans have four phases, with each phase looking at different aspects of safety and effectiveness, in increasingly larger groups of people. Because study subjects must be followed for certain minimum lengths of time, clinical trials can take a few years even in the best-case scenarios, and are costly to conduct.

Before clinical trials can even begin, preliminary research in the laboratory must indicate that a treatment shows promise. Financial support is critical at this stage to help ensure the best scientific minds are hired to conduct the research as effectively and as thoroughly as possible.


Is best case scenario the same thing as “pie in the sky”? I hope not, but so far it has been.