Macrophages by Harris at Karolinska Institutet

Quote from the abstract:

Clinical therapeutic efficacy was assessed after adoptive transfer in NOD T1D, and after a single transfer of M2r macrophages, >80% of treated NOD mice were protected against T1D for at least 3 months, even when transfer was conducted just prior to clinical onset.

Quote from the news article:

At the end of the follow-up period only 25% of the mice receiving the cytokine-treated macrophages had developed Type 1 diabetes, while 83% of the control groups had become sick. 

"The cell therapy was initiated just 2 weeks before mice developed clinical diabetes", says Dr Harris. "At this stage few insulin-producing beta cells remain in the pancreas, yet we were able to protect these so that the mice never developed diabetes. Such a successful late-stage intervention has never previously been reported and is a significant result of our study. At the time of their clinical Type 1 diabetes diagnosis, most human individuals have already lost most of their insulin-producing beta cells."

News: http://bulletin.sciencebusiness.net/news/75792/Karolinska-researchers-prevent-mice-from-developing-diabetes
Abstract: http://diabetes.diabetesjournals.org/content/early/2012/06/20/db11-1635.abstract

Stem Cells (hESCs) by Rezania and Kieffer at University of British Columbia and BetaLogics

I'm not sure I should count this as a "cured in mice".  Basically the researchers took mice that had a compromised immune system, and then made them diabetic by poisoning their pancreas, and then cured them by implanting human embryonic stem cells (hESCs).  I think this proves that they know the recipe to turn hESCs into functional beta cells (a huge advance in itself), but it is not a cure for real type-1 diabetes, because the autoimmune attack would still kill off the new beta cells.  The mice used in this experiment did not have autoimmune (type-1) diabetes.

From the abstract:

As graft-derived insulin levels increased over time, diabetic mice were weaned from exogenous insulin and human C-peptide secretion was eventually regulated by meal and glucose challenges.

Abstract: http://diabetes.diabetesjournals.org/content/early/2012/06/25/db11-1711.abstract
Press release: http://www.eurekalert.org/pub_releases/2012-06/uobc-scc062512.php
News article: http://www.dailyrx.com/news-article/type-1-diabetic-mice-no-longer-need-insulin-treatment-after-stem-cell-transplantation-1

Non-Depleting Antibodies by Yi and Tisch at University of North Carolina

From the news article:

In some of the recently diagnosed NOD mice, blood sugar levels returned to normal within 48 hours of treatment. Within five days, about 80 percent of the animals had undergone diabetes remission, reversal of clinical diabetes. 

"The protective effect is very rapid, and once established, is long-term," [Tisch] said. "We followed the animals in excess of 400 days after the two antibody treatments, and the majority remained free of diabetes. And although the antibodies are cleared from within the animals in 2-3 weeks after treatment, the protective effect persists." The study showed that beta cells in the NOD mice had been rescued from ongoing autoimmune destruction.

I was asked if this is new concept or not.  Basically, I think that, in science, everything is based on work done before, so deciding that something is "new" or not usually involves arguing about the definition of "new", and is a waste of time.  Everything has some new parts and some old parts.

However, I will say that work in non-depleting antibodies targeting CD4 and CD8 to cure or prevent type-1 diabetes has been going on for about 20 years.  (Pubmed references from 1992, so the research actually has gone on longer than that.)  So from that point of view, I don't think this basic approach is completely novel, but I'm hoping these researchers are using a different antibody than has been used in the past, and that they will be more successful in humans than previous attempts.

Sources:
http://www.sciencedaily.com/releases/2012/07/120706013709.htm
http://diabetes.diabetesjournals.org/content/early/2012/06/25/db12-0098

Much older stuff:
http://onlinelibrary.wiley.com/doi/10.1002/eji.1830220735/abstract
http://www.freepatentsonline.com/5670150.html