Type 1 diabetes (TID) is an autoimmune disease that results from the selective destruction of insulin-producing ?-cells in pancreatic islets. The diagnosis of TID is commonly preceded by a long prodromal period which includes seroconversion to islet autoantibody positivity and subtle metabolic disturbances. Thus there is still a need for improved methods of assessing status, risk or prognosis of T1D. It is hypothesized that gut microbiota may affect T1D incidence via the modulation of the host innate immune system. In particular, the literature describes a decreased diversity in the intestinal microbiota in at risk children with seroconversions who progressed to T1D compared to those who did not progress during the study observation period. Because this observation takes place in the time window between the first seroconversion and much before the T1D diagnosis, it suggests that an event linked to the intestinal microbiota could contribute to the progression of islet autoimmunity towards clinical T1D. Moreover, this decrease of intestinal microbiota diversity seems to be associated with an increased intestinal permeability in at risk children who have at least two autoantibodies. Recently published data also show modification of glycolipids in the stools of at risk children.rnrnThus, the present invention relates to methods and kits of assessing status, risk or prognosis of T1D. The inventors have observed different alterations of iNKT and MAIT cells quantity, frequency and markers in T1D patients compared to controls and also in children with recent onset T1D compared to control children or children with established T1D. The present invention relates to a method of assessing status, risk or prognosis of T1D in a subject using iNKT and MAIT cells as biomarkersrnrnScientific publication(s):rnNat Immunol., 2017 Dec, Rouxel O. et al., Cytotoxic and regulatory roles of mucosal-associated invariant T cells in type 1 diabetes, doi: 10.1038/ni.3854