Biology subjects

Kufer, T. A.

Publications and source records attributed to Kufer, T. A..

4 recordsLinked to original sources

bioRxiv2025

NLRC5 expression in tumor cells is critical to activate adaptive and innate antitumor immune responses

Tumors evade cytotoxic T lymphocyte (CTL)-mediated killing by downregulating MHC class-I, mainly resulting from the loss of its transcriptional activator NLRC5. Expressing full-length NLRC5 (NLRC5-FL) or a shorter NLRC5-CIITA fusion protein termed NLRC5 super-activator (NLRC5-SA) in cancer cells upregulates MHC-I expression and promotes antitumor immunity. To distinguish the role of NLRC5 expressed within tumor cells and antigen presenting cells, we studied B16-F10 melanoma expressing NLRC5-FL (B16-N-FL) or NLRC5-SA (B16-N-SA) in Nlrc5+/+ and Nlrc5-/- mice. Both tumors were efficiently controlled in both Nlrc5+/+ and Nlrc5-/- hosts with abundant immune cell infiltration, enriched for activated and differentiated CD8+ and CD4+ T cells, NK, NKT and iNKT cells. B16-N-FL and B16-N-SA tumors showed increased collagen deposition and vascularization, with upregulation of CCL4 and CXCL9 chemokine genes in B16-N-SA tumors. Depletion of either CD8+ T cells or NK1.1+ cells increased the growth of B16-N-FL and B16-N-SA tumors in Nlrc5+/+ mice, and that of B16-N-SA tumors in Nlrc5-/- hosts. Proteomes of B16-N-FL and B16-N-SA cells showed downmodulation of dominant tumor antigens and upregulation of ubiquitination and protein processing pathway proteins. Differentially expressed proteins shared between B16-N-FL and B16-N-SA cells showed enrichment in phagosome and autophagy pathways. We conclude that tumor cell-intrinsic NLRC5 expression is critical for the activation of adaptive and innate immune cells, and establishment of an immune-supportive tumor microenvironment to permit immune cell infiltration and their effector functions and achieve tumor control. NLRC5 expression in APCs is dispensable to mediate these effects. Delivering NLRC5-SA is a promising approach to restore antitumor immune responses in MHC-I-low immune evasive tumors. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=134 SRC="FIGDIR/small/695247v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@1bc4f51org.highwire.dtl.DTLVardef@1fb5b03org.highwire.dtl.DTLVardef@11448edorg.highwire.dtl.DTLVardef@bff26c_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2025

C-terminal lysine residues localise NLRP10 at lipid compartments and govern NLRP10 oligomer formation

NLRP10 is an atypical member of the NOD-like receptor (NLR) family because it lacks a leucine-rich repeat domain at its C-terminus. Recently, NLRP10 has been shown to form an inflammasome, however, the mechanism and the trigger of activation remain elusive. Here, we show that in human epithelial cells and keratinocytes NLRP10 oligomerises in response to the stressor m-3M3FBS. NLRP10 co-localises with ASC upon overexpression, but ASC nucleation and recruitment were different to other NLRPs. While neither ATP hydrolysis nor the pyrin domain were required, the C-terminal tail region (aa 584-655) was both necessary and sufficient for oligomerisation. Generation of chimeric proteins showed that the function of the tail is conserved between human and mouse NLRP10 in respect to aggregation but convers different protein stability. Changes in the subcellular localisation of NLRP10 and oligomerization were dependent on the presence of evolutionarily conserved lysine residues in the tail region, which localise the majority of NLRP10 at lipid droplets. Our study identifies the C-terminal basic tail of NLRP10 as a key regulatory element for oligomerisation and localisation at lipid interfaces. These findings underline differences of NLRP10 activation in respect to other inflammasome forming NLRPs and suggest a role of lipids in NLRP10 activation.

immunology↗

bioRxiv2019

NOD1 mediates non-canonical inflammasome processing of interleukin-18 in epithelial cells to Helicobacter pylori infection.

The interleukin-1 family members, IL-1{beta} and IL-18, are processed into their biologically active forms by multi-protein complexes, known as inflammasomes. Although the inflammasome pathways that mediate IL-1{beta} processing in myeloid cells have been extensively studied, those involved in IL-18 processing, particularly in non-myeloid cells, are still poorly understood. Here, we have identified the cytosolic sensor NOD1 as a key regulator of IL-18 processing in epithelial cells responding to Helicobacter pylori infection. Importantly, NOD1 processing of IL-18 occurs independently of the canonical inflammasome proteins, NLRP3 and ASC. Instead, NOD1 interacts directly with caspase-1 via homotypic binding of caspase-activation recruitment domains. We show that IL-18 is important in maintaining tissue homeostasis and protecting against pre-neoplastic changes due to gastric H. pylori infection. These findings reveal an unanticipated role for NOD1 in a new type of inflammasome that regulates epithelial cell production of bioactive IL-18 with tissue protective functions.

immunology↗

bioRxiv2019

XIAP controls RIPK2 signaling by preventing its deposition in speck-like structures

The receptor interacting serine/threonine kinase 2 (RIPK2) is essential for linking activation of the pattern recognition receptors NOD1 and NOD2 to cellular signaling events. Recently, it was shown that RIPK2 forms higher order molecular structures in vitro, which were proposed to activate signaling. Here, we demonstrate that RIPK2 forms detergent insoluble complexes in the cytosol of host cells upon infection with invasive enteropathogenic bacteria. Formation of these structures occurred after NF-{kappa}B activation and depends on the CARD of NOD1 or NOD2. Complex formation upon activation was dependent on RIPK2 autophosphorylation at Y474 and influenced by phosphorylation at S176. Inhibition of activity of the cIAP protein XIAP induced spontaneous complex formation of RIPK2 but blocked NOD1-dependet NF-{kappa}B activation. Using immunoprecipitation, we identified 14-3-3 proteins as novel binding partners of non-activated RIPK2, whereas complexed RIPK2 was bound by the prohibitin proteins Erlin-1 and Erlin-2. Taken together, our work reveals novel roles of XIAP, 14-3-3 and Erlin proteins in the regulation of RIPK2 and expands our knowledge on the function of RIPK2 posttranslational modifications in NOD1/2 signaling.

immunology↗