Putative factors facilitating development and progression of T1DM. Susceptibility factors such as altered intestinal immune responses with enhanced expression of antigen presenting HLA class II molecules and intracellular adhesion molecule (ICAM)-1 on the intestinal epithelium, leaky intestinal mucosal barrier with low levels of claudin and a background of environmental factors such as aberrant intestinal microbiota and lack of exposure to symbiotic organisms are hypothesized to be involved in the development of T-regulatory responses. And, absence of such response is implicated in the manifestation of autoimmune diseases. A complex interplay between these factors along with socio-economic factors (Sardinia) such as infant nutrition, milk infected with MAP- a putative trigger in genetically susceptible individuals, leads to the manifestation of clinical T1DM over a period of time with destruction of β cells of pancreas and decreased production of insulin. MAP has emerged central to this scenario lately due to the supporting studies from Sardinia that associates MAP with T1DM [17, 28] but not with Type 2 diabetes (T2DM) .