Provided herein are methods of adjusting or selecting a gluten peptide therapy based on the human leukocyte antigen (HLA) genotype, in particular HLA-DQ2.5 homozygosity, of a subject having or suspected of having Celiac disease. Also provided herein are methods of identifying (e.g., diagnosing) a subject, such as a subject having or suspected of having Celiac disease and/or assessing the efficacy of treatment of Celiac disease, e.g. by determining responsiveness to a therapeutic gluten peptide composition or cytokine response, and kits relating thereto.
