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Identification of Mediators of T-cell Receptor Signaling via the Screening of Chemical Inhibitor Libraries
Published on: January 22, 2019
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HLAs: Key regulators of T-cell-mediated drug hypersensitivity
A J Redwood1, R K Pavlos1, K D White2
1Institute for Immunology & Infectious Diseases, Murdoch University, Murdoch, Australia.
HLA
|November 25, 2017
Summary
Adverse drug reactions (ADRs) are often predictable on-target effects. However, immune-mediated ADRs (IM-ADRs) involve unintended interactions, with T-cell mediated reactions strongly linked to specific HLA alleles.
Area of Science:
- Immunology
- Pharmacology
- Genetics
Background:
- Adverse drug reactions (ADRs) are categorized as on-target or off-target.
- On-target ADRs are predictable and dose-dependent, stemming from the drug's primary pharmacological action.
- Off-target ADRs, including immune-mediated ADRs (IM-ADRs), result from unintended drug interactions or immune responses.
Purpose of the Study:
- To review the immunogenetics and pathogenesis of immune-mediated ADRs.
- To explore how Human Leukocyte Antigen (HLA) associations inform drug screening and mechanistic understanding.
Main Methods:
- Literature review of immunogenetics and pathogenesis of IM-ADRs.
- Analysis of T-cell-mediated ADRs and their association with HLA risk alleles.
- Discussion of clinical translation of HLA screening for ADR prevention.
Main Results:
- IM-ADRs can be B-cell or T-cell mediated, with T-cell mediated reactions linked to severe clinical outcomes.
- Specific HLA risk alleles, like HLA-B*57:01 for abacavir hypersensitivity, are strongly associated with T-cell mediated ADRs.
- These associations have enabled clinical screening strategies.
Conclusions:
- Understanding the immunogenetics of IM-ADRs is crucial for predicting and preventing severe drug reactions.
- HLA associations provide valuable insights into ADR pathogenesis and guide the development of personalized medicine approaches.
- Pre-drug screening based on HLA type can mitigate the risk of life-threatening IM-ADRs.
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