Biology subjects

Calvanese, A. L.

Publications and source records attributed to Calvanese, A. L..

3 recordsLinked to original sources

bioRxiv2024

Hepatic iNKT cells facilitate colorectal cancer metastasis by inducing a fibrotic niche in the liver

The liver is an important metastatic organ that contains many innate immune cells, yet little is known about their role in anti-metastatic defense. We investigated how invariant natural killer T (iNKT) cells influence colorectal cancer-derived liver metastasis using different models in immunocompetent mice. We found that hepatic iNKT cells promote metastasis by creating a supportive niche for disseminated cancer cells. Mechanistically, iNKT cells respond to disseminating cancer cells by producing the fibrogenic cytokines IL-4 and IL-13 in a TCR-independent manner. Selective abrogation of IL-4 and IL-13 sensing in hepatic stellate cells prevented their transdifferentiation into extracellular matrix-producing myofibroblasts, which hindered metastatic outgrowth of disseminated cancer cells. This study highlights a novel tumor-promoting axis driven by iNKT cells in the initial stages of metastasis.

immunology↗

bioRxiv2024

Inflammatory cytokines mediate the induction of and awakening from metastatic dormancy

Metastases arise from disseminated cancer cells (DCCs) that detach from the primary tumor and seed distant organs. There, quiescent DCCs can survive for an extended time, a state referred to as metastatic dormancy. The mechanisms governing the induction, maintenance, and awakening from metastatic dormancy are unclear. We show that the differentiation of dormancy-inducing CD8+ T cells requires CD4+ T cell help, and that IFN{gamma} directly induces dormancy in DCCs. The maintenance of metastatic dormancy, however, is independent of T cells. Instead, awakening from dormancy requires an inflammatory signal, and we identified CD4+ T cell-derived IL- 17A as an essential wake-up signal for dormant DCCs in the lungs. Thus, the induction and awakening from metastatic dormancy require an external stimulus, while the maintenance of dormancy does not rely on the continuous surveillance by lymphocytes.

immunology↗

bioRxiv2024

Sustained innate interferon is an essential inducer of tertiary lymphoid structures

Tertiary lymphoid structures (TLS) resemble follicles of secondary lymphoid organs and develop in non-lymphoid tissues during inflammation and cancer. Which cell types and signals drive the development of TLS is largely unknown. To investigate early events of TLS development in the lungs, we repeatedly instilled p(I:C) plus ovalbumin (Ova) intranasally. This induced TLS ranging from lymphocytic aggregates to organized and functional structures containing germinal centers. We found that TLS development is independent of FAP+ fibroblasts, alveolar macrophages or CCL19 but crucially depends on type I (IFN-I)-but not type III interferon (IFN-III)-signaling. Mechanistically, IFN-I initiates two synergistic pathways that culminate in the development of TLS. On the one hand, IFN-I induces lymphotoxin (LT) in lymphoid cells, which stimulate stromal cells to produce the B-cell-attracting chemokine CXCL13 through LT{beta}R-signaling. On the other hand, IFN-I is sensed by stromal cells that produce the T-cell-attracting chemokines CXCL9, CXCL10 as well as CCL19 and CCL21 independently of LT{beta}R. Consequently, B-cell aggregates develop within a week, whereas follicular dendritic cells and germinal centers appear after 3 weeks. Thus, sustained production of IFN-I together with an antigen is essential for the induction of functional TLS in the lungs. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=152 SRC="FIGDIR/small/591846v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@a2d940org.highwire.dtl.DTLVardef@165294aorg.highwire.dtl.DTLVardef@79c43forg.highwire.dtl.DTLVardef@4316ce_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗