Dysbiosis of the intestinal microbiota affecting the gut barrier could be triggering Type 1 Diabetes (T1D), the second most frequent autoimmune disease in childhood. This study compared the structure of the fecal microbiota in 29 mestizo children aged 7–18 years, including 8 T1D at onset, 13 T1D after 2 years treatment and 8 healthy controls. Clinical information was collected, predisposing haplotypes were determined; the fecal DNA was extracted, the V4 region of the 16S rRNA gene amplified and 454-pyrosequenced. The newly diagnosed T1D cases had high levels of the genus Bacteroides (p < 0.004), whereas the control group had a gut microbiota dominated by Prevotella. Children with T1D treated for ≥2 years had levels of Bacteroides and Prevotella compared to those of the control group. The gut microbiota of newly diagnosed T1D cases is altered, but whether it is involved in disease causation or is a consequence of host selection remains unclear.

Background: Consumption of seafood can produce allergic symptoms in susceptible individuals and crustacean allergies are the most frequently reported causes of allergic reactions. Methods: An allergen from the muscle of the white shrimp Litopenaeus vannamei was purified by ion exchange chromatography and identified by mass spectrometry of tryptic peptides and its specific enzymatic activity. Moreover, the corresponding full-length cDNA was obtained from an L. vannamei muscle cDNA library. Results: A 40-kDa protein was purified and identified as arginine kinase and its cDNA of 1.4 kb encoded a 356 amino acid protein. The obtained arginine kinase was recognized by IgE in serum from shrimp-allergic individuals using ELISA and immunoblotting analysis. Conclusions: This is the first allergen reported for the Pacific white shrimp species; it was named Lit v 2 and has a 96% identity to Pen m 2 from Penaeus monodon.

Type 1 diabetes (T1D) is the second most frequent autoimmune disease in childhood. The long-term micro- and macro-vascular complications of diabetes are associated with the leading causes of disability and even mortality in young adults. Understanding the T1D etiology will allow the design of preventive strategies to avoid or delay the T1D onset and to help to maintain control after developing. T1D development involves genetic and environmental factors, such as birth delivery mode, use of antibiotics, and diet. Gut microbiota could be the link between environmental factors, the development of autoimmunity, and T1D. In this review, we will focus on the dietary factor and its relationship with the gut microbiota in the complex process involved in autoimmunity and T1D. The molecular mechanisms involved will also be addressed, and finally, evidence-based strategies for potential primary and secondary prevention of T1D will be discussed.