**5. Proposed immunological models of T cell activation in Stevens-Johnson syndrome/toxic epidermal necrolysis**

There are three proposed models of T cell activation in Stevens-Johnson syndrome/toxic epidermal necrolysis due to drugs (**Figure 4**) [23].

#### **Figure 4.**

*Models of T cell activation in Steven Johnson syndrome and toxic epidermal necrolysis. Abbreviations: APCantigen presenting cells, HLA- human leukocyte antigen, TCR- T cell receptor, HLA- human leukocyte antigen. Adapted from: Hasegawa a and Abe R. recent advances in managing and understanding Stevens-Johnson syndrome and toxic epidermal necrolysis (version 1; peer review: 2 approved). F1000Research 2020, 9(F1000 faculty rev):612.*

*Perspective Chapter: Drug-Induced Severe Cutaneous Adverse Reactions, Diagnostics... DOI: http://dx.doi.org/10.5772/intechopen.108651*

