Figure 2: Schematic showing how transglutaminase (TG)-2 can play a role in inflammation. TG2 is a trigger for the phospholipase (PL) A2, the nuclear factor (NF)-κB and the p38 mitogen activated protein kinase (MAPK) pathways. These may result in the production of pro-inflammatory cytokines and growth factors. Some cytokines may be up or down regulated depending on the context of the experiment/disease. Certain cytokines such as IL4 and IL5 are mediators of Th2 response, causing allergies. In addition, TG function is implicated in phagocytosis including the clearance of apoptotic cells, but delayed clearance is normally not encountered in usual circumstances, except with oxidised lipoproteins and ablation of TG2 in animals.