Vaccine Industry Targets Type 1 Diabetes
Published October 22, 2017 | Vaccination, Future Vaccines
Story Highlights
- People suffering with diabetes have a problem with the insulin-mediated transport of glucose into cells, which is needed for energy.
- Unlike type 2 diabetes (the most common type, which generally is associated with obesity and a sedentary lifestyle and mainly affects adults) type 1 diabetes is increasingly viewed as an autoimmune disorder in which the body mistakenly attacks the pancreatic beta cells that produce insulin.
- A vaccine is in development and human trials are scheduled for 2018 based on the theory that a specific enterovirus is the triggering factor for type 1 diabetes.
It is normal for blood sugar to fluctuate slightly during the day, but it generally stays between 70 and 140 mg/dL2 For instance, blood sugar tends to be low first thing in the morning before eating, and rises rapidly with the first meal. Certain medications, stress, and strenuous exercise also may affect blood glucose levels, as can factors such as dehydration, sleep patterns, menstrual cycle, and extreme weather changes.2
When the body consistently lacks the insulin it needs to transport glucose to the cells, diabetes is the result.
Diabetes Takes Several Forms
Type 1, or juvenile diabetes, is the most common type diagnosed in children and young adults, though it can develop at any age. It also is the more severe form. With type 1 disease, the body stops producing insulin, or at least does not produce enough to provide energy to the cells. Since insulin is critical for cell function, anyone diagnosed with type 1 diabetes must receive daily injections of insulin.3Type 2 diabetes, which is often referred to as “adult onset diabetes,” is more often diagnosed in older people and is commonly seen with obesity and a sedentary lifestyle. However, type 2 diabetes can develop in people of all ages. In the past few decades, type 2 diabetes has been unexpectedly increasing among young children with no clear explanation given by public health officials about why it is increasing has been unexpectedly increasing among young children with no clear explanation given by public health officials about why it is increasing.4 5
Type 2 diabetes is now the most common type of diabetes being diagnosed, accounting for as much as 90 percent of all new diabetes cases.3 Type 2 diabetes more often reflects a decrease in the amount of insulin produced, or a fault in the interaction between glucose and insulin so that the mechanism to deliver energy to the cells is not working as it should.4
Gestational diabetes develops during pregnancy and resolves after the birth. Most women with this form of diabetes are able to control the disorder with diet and exercise, but between 10 and 20 per cent will need medical intervention. There is some indication that women whose pre-pregnancy diet was high in animal fat and cholesterol have a higher chance of developing gestational diabetes.
Type 1 Diabetes Does Not Reflect Life Choices
Unlike type 2 diabetes, type 1 diabetes is not related to lifestyle choices but is a lifelong disease that must be managed daily. Scientists believe that type 1 disease is an autoimmune disorder in which the body mistakenly attacks the pancreatic beta cells responsible for creating insulin. It isn’t clear what triggers the diabetic response, but it is thought to involve an “environmental trigger in genetically susceptible people.”5The Enterovirus Theory Aims at a Vaccine
One widely held research theory is that type 1 diabetes is activated by an enterovirus—a type of RNA virus that typically shows up in the gastrointestinal tract. Enteroviruses are thought to have an attraction to insulin-producing beta cells in the pancreas that may set up a chronic infection in the cells leading to autoimmunity, and stat least one study has shown that children with diabetes have a threefold history of enterovirus infection compared to children without diabetes.6Promoters of this theory include Heikki Hyöty, MD and his team from the University of Tampere in Finland. They looked at hundreds of infectious enteroviruses found in humans, pinpointed six they thought had an association with type 1 diabetes, and finally settled on one in particular they believed was associated with the greatest risk: The coxsackievirus B1, which had been shown to spur the body into attacking beta cells and had been linked to type 1 diabetes in children.6
From there, they developed a prototype vaccine they tested in laboratory animals. With their reported success in the lab mice, they are now pressing forward to test the experimental diabetes vaccine in humans.
Scheduled to begin in 2018, the human vaccine testing will go through three phases: First, the diabetes vaccine will be tested for safety in a small group of adults. Second, children will be vaccinated to look at the safety and effectiveness of the vaccine against enteroviruses. Finally, children will be vaccinated to see if the vaccine prevents the development of type 1 diabetes. These children will need to be followed for up to eight years to confirm that the vaccine reduced the expected incidence of disease.7
There May Be Other Factors at Play
Other scientists suggest that while there may be correlation with enteroviruses, it is “far from a smoking gun” and is, in itself, inconclusive. Other researchers are investigating other environmental triggers that may trigger the development of diabetes, such as socioeconomic factors, diet, and exposure to toxins.8Some researchers suggest that the “hygiene hypothesis” may provide the explanation: As the level of hygiene in society as a whole has improved, the diversity of bacteria the body is forced to deal with as decreased, giving the immune system less to do and causing it to turn against itself.7 This theory holds that this lack of natural infectious microbe challengers has helped fuel the overall increase in incidence of autoimmune disorders like type 1 diabetes.9
It Comes Down to Gut Microflora
It could all come down to a disruption in the composition of gut microflora that populate the human microbiome that is causing a rise in autoimmune disorders like diabetes.8Whatever it is, it is happening with greater frequency than ever before: The incidence of both types 1 and 2 diabetes is increasing every year in the U.S.10 The increasing prevalence is even more pronounced in Finland, which is thought to have the highest rate of type 1 diabetes in the world.11
A study led by Mikael Knip, MD, professor of pediatrics at the University of Helsinki, has looked at the possibility that exposure to a particular viral or bacterial infectious agent early in life may protect children from developing type 1 disease. Differences in microbial flora between a group of Finnish children and genetically biosimilar groups of children from two surrounding areas were compared to see why their rates of type 1 diabetes were so different. It was concluded that the poorest children, who had greatest exposure to outside air, dirt, animals, and therefore a much greater diversity of environmental microbes also had the most diversity in their microflora, and the lowest risk of developing type 1 diabetes.9
Dr. Knip says it’s not yet clear whether there is a specific microbe protecting the children or whether it is the overall microbial load that is important. He stresses that he doesn’t want to “turn back the clock on sanitary conditions in Finland” but hopes instead that a drug or probiotic may be developed that could “stimulate the developing child’s immune system.” He says, “Current probiotics are too mild… You need more offensive microbes to get protection against autoimmune disease like diabetes.”11
A good number of grandmothers, who raised children in the 20th century, are likely to give this common sense advice: “How about letting them play in the real dirt?”
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