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Staphylococcal alpha-toxin tilts the balance between malignant and non-malignant CD4⁺ T cells in cutaneous T-cell lymphoma.

ABSTRACT: Staphylococcus aureus is implicated in disease progression in cutaneous T-cell lymphoma (CTCL). Here, we demonstrate that malignant T cell lines derived from CTCL patients as well as primary malignant CD4⁺ T cells from Sézary syndrome patients are considerably more resistant to alpha-toxin-induced cell death than their non-malignant counterparts. Thus, in a subset of Sézary syndrome patients the ratio between malignant and non-malignant CD4⁺ T cells increases significantly following exposure to alpha-toxin. Whereas toxin-induced cell death is ADAM10 dependent in healthy CD4⁺ T cells, resistance to alpha-toxin in malignant T cells involves both downregulation of ADAM10 as well as other resistance mechanisms. In conclusion, we provide first evidence that Staphylococcus aureus derived alpha-toxin can tilt the balance between malignant and non-malignant CD4⁺ T cells in CTCL patients. Consequently, alpha-toxin may promote disease progression through positive selection of malignant CD4⁺ T cells, identifying alpha-toxin as a putative drug target in CTCL.

SUBMITTER: Blumel E

PROVIDER: S-EPMC6791457 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Staphylococcus aureus alpha-toxin inhibits CD8+ T cell-mediated killing of cancer cells in cutaneous T-cell lymphoma.

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