Role of T cells in nonimmediate allergic drug reactions.
OBJECTIVE
This review presents the current knowledge of the role of T cells in drug allergy manifesting as exanthematous, pustular and bullous skin diseases, collectively referred to as nonimmediate allergic drug reactions.


RESULTS
Both CD4+ and CD8+ T cells producing type 1 and type 2 cytokines and endowed with cytotoxic properties are involved in nonimmediate allergic drug reactions. Recent studies have confirmed that CD8+ T cells play a major role in the pathophysiology of nonimmediate allergic drug reactions, and have characterized new cytotoxic molecular pathways responsible for the severity of the bullous forms of nonimmediate allergic drug reactions.


CONCLUSIONS
Nonimmediate allergic drug reactions are mediated by T cells and mostly affect the skin. Nonimmediate allergic drug reactions comprise several diseases ranging from the frequent and benign maculo-papular exanthema to the severe and rare toxic epidermal necrolysis. Progress in the knowledge of the pathophysiology of nonimmediate allergic drug reactions comes from a better understanding of the mechanisms of drug recognition by T cells and from a careful analysis of the phenotype and functions of CD4+ and CD8+ T cells infiltrating the skin lesions. Recent studies have confirmed that the different clinical forms of nonimmediate allergic drug reactions are associated with distinct types of T cell-mediated skin inflammation. However, CD8+ T cells appear as major effector T cells in most of the nonimmediate allergic drug reactions. Future studies to analyze the early cellular and molecular events leading to the development of the allergic skin reaction will be helpful in order to define diagnostic and therapeutic targets.
Rozieres
Aurore
A
Université Lyon1, UFR Lyon Sud, Oullins 69600, France.
Vocanson
Marc
M
Saïd
Benoit Ben
BB
Nosbaum
Audrey
A
Nicolas
Jean-Francois
JF
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D003875:Drug Eruptions; D004342:Drug Hypersensitivity / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D005076:Exanthema; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000139:chemically induced / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D008221:Lymphoid Tissue / Q000276:immunology* / Q000473:pathology; D012867:Skin / Q000276:immunology* / Q000473:pathology