The immunochemistry of Triticeae glutens is important in several inflammatory diseases. It can be subdivided into innate responses (direct stimulation of immune system), class II mediated presentation (HLA DQ), class I mediated stimulation of killer cells, and antibody recognition. The responses to gluten proteins and polypeptide regions differs according to the type of gluten sensitivity. The response is also dependent on the genetic makeup of the human leukocyte antigen genes. In gluten sensitive enteropathy, there are four types of recognition, innate immunity (a form of cellular immunity priming), HLA-DQ, and antibody recognition of gliadin and transglutaminase. With idiopathic gluten sensitivity only antibody recognition to gliadin has been resolved. In wheat allergy, the response pathways are mediated through IgE against other wheat proteins and other forms of gliadin. Innate immunity Innate immunity to gluten refers to an immune response that works independently of T-cell receptor or antibody recognition of the 'innate' peptide. This peptide acts directly on cells, such as monocytes, stimulating their growth and differentiation. Innate immunity to gluten is complicated by an apparent role gluten has in bypassing normal host defense and peptide exclusion mechanisms in the gut. While not truly innate, these activities allow gliadin to enter into areas where many lymphocytes patron. In bypassing these filters gliadin alters the normal behavior of both digestive cells, called enterocytes or epithelial cells, and lymphocytes. This increases the potential of causing sensitivity (see Underlying Conditions). One potential explanation of why certain people become sensitive is that these individuals may not produce adequate peptidases in some areas of the gut, allowing these peptides to survive. Other explanation for some may be that food chemicals or drugs are weakening the defenses. This can be the case with ω5-gliadin allergy with salicylate sensitivity. There is no clear reasoning, either from genetics or from long term studies of susceptible individuals why these gut peptide restrictions would change. Once inside, α-9 gliadin 31-55 shows the ability to activate undifferentiated immune cells that then proliferate and also produce inflammatory cytokines, notably interleukin 15 (IL-15). This produces a number of downstream responses that are pro-inflammatory. The other peptide that may have innate behavior is the "CXCR3" receptor binding peptides, the receptor exists on enterocytes, the brush border membrane cells. The peptide displaces an immune factor and signals the disruption of the membrane seal, the tight junctions, between cells. Alpha gliadin 31-43 Gluten bears an innate response peptide