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There is evidence that innate immune responses coopt adaptive properties such as memory. Whether T cells harness innate immune signaling pathways to diversify their repertoire of effector functions remains unknown. Here, we found that human T cells expressed gasdermin E (GSDME), a membrane pore-forming molecule that has recently been shown to execute pyroptotic cell death and thus to serve as a potential cancer checkpoint. In T cells, GSDME expression was, in contrast, associated with durable viability and was repurposed for the tunneled release of the alarmin IL-1a. This property was restricted to a subset of human Th17 cells with specificity for C. albicans and was regulated by a T cell-intrinsic NLRP3 inflammasome and its engagement of a proteolytic cascade of successive caspase-8, caspase-3 and GSDME cleavage following T-cell receptor stimulation and calcium-licensed calpain maturation of the pro-IL1a form. Our results propose GSDME pore formation in T cells as a mechanism of unconventional cytokine release through harnessing of innate signaling platforms in response to adaptive stimuli. This finding diversifies the functional repertoire and mechanistic equipment of T cells with implications for anti-fungal host defense.

In the version of this article initially published, in the Acknowledgements, the grant number for the Start Grant TWILIGHT awarded to M.A.L. by the European Research Council was omitted. The correct wording is “Supported by...the European Research Council (...Start Grant TWILIGHT (637801) to M.A.L.).” The error has not been corrected in the original article.

Background. Single-nucleotide polymorphisms (SNPs) in immune genes have been associated with susceptibility to invasive mold infection (IMI) among hematopoietic stem cell but not solid-organ transplant (SOT) recipients. Methods. Twenty-four SNPs from systematically selected genes were genotyped among 1101 SOT recipients (715 kidney transplant recipients, 190 liver transplant recipients, 102 lung transplant recipients, 79 heart transplant recipients, and 15 recipients of other transplants) from the Swiss Transplant Cohort Study. Association between SNPs and the end point were assessed by log-rank test and Cox regression models. Cytokine production upon Aspergillus stimulation was measured by enzyme-linked immunosorbent assay in peripheral blood mononuclear cells (PBMCs) from healthy volunteers and correlated with relevant genotypes. Results. Mold colonization (n = 45) and proven/probable IMI (n = 26) were associated with polymorphisms in the genes encoding interleukin 1β (IL1B; rs16944; recessive mode, P = .001 for colonization and P = .00005 for IMI, by the log-rank test), interleukin 1 receptor antagonist (IL1RN; rs419598; P = .01 and P = .02, respectively), and β-defensin 1 (DEFB1; rs1800972; P = .001 and P = .0002, respectively). The associations with IL1B and DEFB1 remained significant in a multivariate regression model (P = .002 for IL1B rs16944; P = .01 for DEFB1 rs1800972). The presence of 2 copies of the rare allele of rs16944 or rs419598 was associated with reduced Aspergillus-induced interleukin 1β and tumor necrosis factor α secretion by PBMCs. Conclusions. Functional polymorphisms in IL1B and DEFB1 influence susceptibility to mold infection in SOT recipients. This observation may contribute to individual risk stratification