The master regulators of delayed-type drug hypersensitivity reactions

Area of Science:

• Immunology
• Dermatology
• Pharmacology

Background:

• Delayed-type drug hypersensitivity reactions (DTHRs) encompass a spectrum of immune responses, from mild rashes to severe cutaneous adverse reactions like Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS).
• These reactions are primarily mediated by drug-specific T cells and influenced by intricate regulatory networks within the immune system.

Purpose of the Study:

• This review focuses on recent breakthroughs in understanding the key regulatory mechanisms that drive the development of DTHRs.
• The aim is to elucidate the master regulators orchestrating DTHR pathogenesis.

Main Methods:

• This review synthesizes current research on DTHR pathogenesis, focusing on molecular and cellular regulatory pathways.
• It examines the roles of cytokine loops, signaling pathways, epigenetic modifications, and innate-adaptive immune cell interactions.

Main Results:

• HLA-restricted T-cell activation is amplified by cytokine loops, such as the tumor necrosis factor-α axis, which can impair peripheral tolerance and recruit immune effectors.
• The JAK-STAT pathway is implicated in both immune and stromal cells during DTHRs. Epigenetic modifications and novel immunomodulatory circuits involving neuropeptides and innate immune cells also play critical roles.
• Epidermal damage in DTHRs results from converging cell death pathways, including apoptosis, ferroptosis, and necroptosis, potentially triggered by exosomal signals.

Conclusions:

• Understanding the complex regulatory layers involved in DTHRs is crucial for identifying new diagnostic biomarkers.
• These insights pave the way for developing targeted therapies and advancing precision medicine approaches for managing DTHRs.