Scientists discovered that a specially engineered probiotic bacteria called Lactococcus lactis containing a protein called HSP65 may help prevent type 1 diabetes in mice. Type 1 diabetes happens when the body’s immune system accidentally attacks cells that make insulin, the hormone that controls blood sugar. In this study, mice that received this special probiotic were protected from developing diabetes and had lower blood sugar levels. The bacteria worked by training the immune system to be more tolerant and less likely to attack the body’s own cells. While these results are promising, the research was done in mice, so scientists need to do more studies in humans before this treatment could be used as medicine.

The Quick Take

  • What they studied: Whether a genetically modified probiotic bacteria containing a special protein could train the immune system to prevent type 1 diabetes
  • Who participated: Laboratory mice and immune cells from people with type 1 diabetes were used in this research. The exact number of mice wasn’t specified in the available information
  • Key finding: Mice that received the special probiotic bacteria (L. lactis-HSP65) developed diabetes much less often than mice that didn’t receive it, and their blood sugar stayed lower. This protection only worked when a specific immune system receptor called TLR2 was present
  • What it means for you: This research suggests a potential new way to prevent type 1 diabetes by using probiotics to retrain the immune system. However, this is early-stage research in mice, and much more testing in humans would be needed before this could become a treatment. People with type 1 diabetes should continue following their doctor’s current treatment plans

The Research Details

This was a laboratory research study where scientists created a special probiotic bacteria by adding a protein called HSP65 to Lactococcus lactis, a common bacteria found in yogurt and other fermented foods. They tested this bacteria in two ways: first by growing immune cells in dishes to see how they responded, and second by giving the bacteria to mice to see if it could prevent diabetes from developing.

The researchers also studied immune cells taken from people who already have type 1 diabetes to understand what was different about their immune systems. They compared mice that received the special probiotic to mice that didn’t receive it, and they also tested mice that were missing a specific immune receptor called TLR2 to understand how important it was for the treatment to work.

This type of research is called a preclinical study because it happens in the laboratory and in animals before any human testing would occur. The scientists were looking for proof that their idea could work and understanding the biological mechanisms behind it.

Understanding how the immune system goes wrong in type 1 diabetes is crucial for developing new treatments. This research approach is important because it combines laboratory experiments with animal studies to show both how something works and whether it actually prevents disease. By testing in mice first, scientists can gather safety and effectiveness information before considering human trials. The study also identified the specific immune system pathway involved, which helps explain why the treatment works

This research was published in a peer-reviewed scientific journal, meaning other experts reviewed it before publication. The study used both laboratory experiments and animal models, which provides multiple lines of evidence. However, the sample size of mice wasn’t specified in the available information, which makes it harder to assess the statistical strength. The research was conducted in mice, not humans, so results may not directly apply to people. The findings are promising but represent early-stage research that would need confirmation in larger studies and eventually human trials

What the Results Show

Mice that received the special probiotic bacteria (L. lactis-HSP65) showed strong protection against developing type 1 diabetes. These mice had significantly lower blood sugar levels and developed diabetes much less frequently compared to mice that didn’t receive the treatment. The protected mice showed specific changes in their immune systems: they had more immune cells called dendritic cells that express TLR2, and they had more regulatory T cells (Tregs), which are immune cells that help calm down the immune system and prevent it from attacking the body’s own tissues.

The researchers found that the special bacteria worked by triggering a specific immune pathway. The bacteria activated a receptor called TLR2 on immune cells, which then produced protective substances like IL-10 and TGF-β. These substances helped create an environment where the immune system became more tolerant and less likely to attack insulin-producing cells.

When scientists tested the bacteria in mice that were genetically engineered to lack the TLR2 receptor, the protective effects completely disappeared. This proved that TLR2 was absolutely essential for the treatment to work. Similarly, when they removed the ability to produce IL-10, the immune cells could no longer create the protective regulatory T cells, showing that this molecule was also critical to the mechanism.

The research showed that immune cells from people with type 1 diabetes had problems compared to healthy people. Specifically, their dendritic cells (immune cells that help direct immune responses) had lower expression of genes related to immune tolerance and had less TLR2 on their surface. When the researchers added the HSP65 protein to these human immune cells in the laboratory, it increased TLR2 expression and helped the cells develop into a more tolerant type. This suggests the mechanism discovered in mice might also be relevant in humans, though this would need to be confirmed with further research

This research builds on previous studies showing that probiotics can influence the immune system and that heat shock proteins like HSP65 have anti-inflammatory properties. The novel contribution of this study is combining these two concepts—using a probiotic bacteria to deliver HSP65 directly to the gut—and showing that this combination can prevent type 1 diabetes in mice. The identification of the TLR2 pathway as the critical mechanism adds new understanding to how probiotics might work for autoimmune diseases. This fits with growing research interest in using the gut microbiota and probiotics as treatments for autoimmune conditions

This study was conducted entirely in mice and laboratory experiments, so the results may not directly translate to humans. Type 1 diabetes in mice doesn’t perfectly mimic the disease in people, so the treatment might work differently or not at all in humans. The exact number of mice used in the study wasn’t clearly specified, making it difficult to assess the statistical power of the findings. The study didn’t test whether the treatment would work in mice that already had diabetes—only whether it could prevent the disease from developing in the first place. Long-term safety and whether the protection lasts over time weren’t fully explored. Additionally, this research hasn’t been tested in humans yet, so we don’t know if the special bacteria would be safe or effective in people

The Bottom Line

Based on this research, there are no current recommendations for using this specific probiotic treatment in humans, as it has only been tested in mice. People with type 1 diabetes should continue following their doctor’s prescribed treatment plan with insulin and other medications. General probiotic use for diabetes prevention is not yet supported by sufficient evidence, though some research suggests probiotics may have modest benefits for overall health. Anyone interested in dietary changes should discuss them with their healthcare provider. The confidence level for human application is very low at this stage—this is promising early research that needs much more testing

This research is most relevant to scientists and doctors working on type 1 diabetes treatments and autoimmune disease research. People with type 1 diabetes or those with a family history of the disease might find this research interesting as a potential future treatment option, but they should not expect this to be available as a treatment anytime soon. Parents of children at risk for type 1 diabetes might want to stay informed about this research direction. People without type 1 diabetes should not assume this research applies to them or use it as a reason to take specific probiotics. Healthcare providers treating type 1 diabetes should be aware of this research direction but cannot yet recommend it to patients

If this research eventually leads to human treatments, it would likely take many years. Typically, promising laboratory research like this would need to go through several more stages: larger animal studies, safety testing, and then human clinical trials in phases 1, 2, and 3. This process usually takes 5-10 years or longer before a new treatment becomes available. Even if all testing goes well, regulatory approval would be needed before the treatment could be prescribed. Patients should not expect this specific treatment to be available in the near future

Want to Apply This Research?

  • Users at risk for or managing type 1 diabetes could track blood sugar levels, insulin doses, and dietary intake to establish baseline patterns. Once new treatments become available, these same metrics would help measure whether any intervention is working. For general users interested in gut health, tracking probiotic intake and digestive symptoms could provide useful data
  • While this specific probiotic isn’t yet available for human use, users could discuss with their doctor whether general probiotic foods like yogurt, kefir, or fermented vegetables might be beneficial as part of their overall health strategy. Users could also use the app to track their interest in emerging diabetes research and set reminders to discuss new treatment options with their healthcare provider at regular appointments
  • For people with type 1 diabetes, the app could help monitor blood sugar control, medication adherence, and overall metabolic health over time. Users could set long-term tracking goals for HbA1c levels (a measure of average blood sugar over 3 months) and work with their healthcare provider to optimize current treatments. As new research develops, the app could help users stay informed about clinical trials they might be eligible for and track their interest in participating in future studies

This research describes laboratory and animal studies only and has not been tested in humans. The findings are preliminary and should not be used to guide personal medical decisions. People with type 1 diabetes should continue following their doctor’s prescribed treatment plan and should not discontinue insulin or other medications based on this research. This study does not represent a currently available treatment. Anyone interested in new diabetes treatments or considering changes to their diabetes management should discuss these with their healthcare provider. This summary is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.