If you have HIV, are undergoing radiation or chemotherapy for cancer, or have a suppressed immune system from autoimmune disease, diabetes or chronic lung disease, you may be at risk for developing chicken pox.

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But during an illness, or when the immune system goes haywire in autoimmune diseases such as diabetes, the attacking T cells take over.

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This technique could potentially be used to deliver vaccines against other infectious diseases such as those administered in childhood, and also vaccines to manage chronic inflammatory and autoimmune conditions such as type-1 diabetes or vaccines to control certain allergies.

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In addition, vitamin D has numerous other roles in the body, and a growing body of research is finding that deficiencies may be associated with an increased risk of certain types of cancer (especially colon cancer), type 2 diabetes, heart disease and autoimmune diseases like multiple sclerosis.

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In addition, emerging research shows a possible role for vitamin D in the prevention or treatment of type 1 diabetes, some cancers, and autoimmune diseases including multiple sclerosis.

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Type 1 diabetes results from a rheumatoid-like autoimmune reaction in which one's own body attacks and destroys the beta cells of the pancreas.

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Type I diabetes is thought to be an "autoimmune" disease in which the body's own immune system - which is meant to fight foreign threats like bacteria - turns on the cells in a gland called the pancreas.

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Patients are at higher risk for Type 1 diabetes, mellitus, collagen vascular diseases, autoimmune thyroid disease.

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Their interest gradually turned to childhood diabetes as evidence increased that it was an autoimmune disease as well.

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