Yun, J,; Mattsson, J,; Schnyder, K,; Fontana, S,; Largiadèr, C, R,; Pichler, W, J,; Yerly, D, (2013). Allopurinol hypersensitivity is primarily mediated by dose-dependent oxypurinol-specific T cell response. Clinical and experimental allergy, 43(11), pp. 1246-1255. Blackwell Scientific Publications 10.1111/cea.12184
Text
,DanaInfo=.aoonlrjrpj0k2-M-x1vESw98+cea12184.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (712kB) |
BACKGROUND
Allopurinol is a main cause of severe cutaneous adverse reactions (SCAR). How allopurinol induces hypersensitivity remains unknown. Pre-disposing factors are the presence of the HLA-B*58:01 allele, renal failure and possibly the dose taken.
OBJECTIVE
Using an in vitro model, we sought to decipher the relationship among allopurinol metabolism, HLA-B*58:01 phenotype and drug concentrations in stimulating drug-specific T cells.
METHODS
Lymphocyte transformation test (LTT) results of patients who had developed allopurinol hypersensitivity were analysed. We generated allopurinol or oxypurinol-specific T cell lines (ALP/OXP-TCLs) from allopurinol naïve HLA-B*58:01(+) and HLA-B*58:01(-) individuals using various drug concentrations. Their reactivity patterns were analysed by flow cytometry and (51) Cr release assay.
RESULTS
Allopurinol allergic patients are primarily sensitized to oxypurinol in a dose-dependent manner. TCL induction data show that both the presence of HLA-B*58:01 allele and high concentration of drug are important for the generation of drug-specific T cells. The predominance of oxypurinol-specific lymphocyte response in allopurinol allergic patients can be explained by the rapid conversion of allopurinol to oxypurinol in vivo rather than to its intrinsic immunogenicity. OXP-TCLs do not recognize allopurinol and vice versa. Finally, functional avidity of ALP/OXP-TCL is dependent on both the induction dose and HLA-B*58:01 status.
CONCLUSIONS AND CLINICAL RELEVANCE
This study establishes the important synergistic role of drug concentration and HLA-B*58:01 allele in the allopurinol or oxypurinol-specific T cell responses. Despite the prevailing dogma that Type B adverse drug reactions are dose independent, allopurinol hypersensitivity is primarily driven by oxypurinol-specific T cell response in a dose-dependent manner, particular in the presence of HLA-B*58:01 allele.