Biology subjects

Frederiks, C. L.

Publications and source records attributed to Frederiks, C. L..

3 recordsLinked to original sources

bioRxiv2025

Site-dependent Treg cell transcriptional reprograming in a metastatic colorectal cancer model holds prognostic significance

In colorectal cancer (CRC), tumor-infiltrating regulatory T (Treg) cells suppress anti-tumor immunity, promoting immune evasion and tumor progression. Effective therapies require selectively targeting tumor-infiltrating Treg (TI-Treg) cells while preserving systemic Treg cells, necessitating insight into their adaptations within the tumor microenvironment. Here, CRC-organoids were implanted in the liver of Foxp3eGFP mice to investigate location-specific phenotypic differences in TI-Treg cells. Tumor tissue exhibited an increased proportion of Treg cells and a decrease of effector CD4 and CD8 T cells compared to matched healthy tissue. RNA sequencing of Treg cells isolated from the spleen, primary liver tumor transplant, or metastases identified gene expression profiles previously associated with CRC-related Treg cells in patients. Location-specific differences included elevated expression of WNT-pathway genes in peritoneal TI-Treg cells compared to liver counterparts. Higher expression of genes upregulated in liver TI-Treg cells correlated with poor CRC prognosis. Splenic Treg cells from tumor-bearing mice displayed distinct transcriptional profiles from both their healthy counterparts and TI-Treg cells, suggesting they represent a distinct CD4+ population. Taken together, these findings highlight TI-Treg cells heterogeneity across different tumor sites and the distinct nature of splenic Treg cells in tumor-bearing hosts.

immunology↗

bioRxiv2024

Basement membrane hydrogels dampen CAR-T cell activation: nanofibrillar cellulose gels as alternative to preserve T cell function in 3D cell cultures.

BackgroundHydrogel-based 3D culture systems are emerging as a valuable tool for preclinical screening of cell-based immunotherapies against solid and hematological malignancies, such as chimeric antigen receptor T (CAR-T) cells. Hydrogels can influence T cell function in a non-desired manner due to their mechanical properties and chemical composition, potentially skewing results in preclinical testing of novel immunotherapeutic compounds. MethodsIn this study, we assess CD4+ T and CAR-T cell activation and proliferation in chemically-undefined matrices (Matrigel and basement membrane extract, BME) and compare them to a synthetic nanofibrillar cellulose (NFC) hydrogel. ResultsRheometric analyses show that NFC is more rigid than Matrigel and BME. Murine CD4+ T cells acquire a regulatory T cell (Treg) phenotype in Matrigel and BME, while this is not observed in NFC. Proliferation and activation of human T cells are higher in NFC than in Matrigel or BME. Similarly, we show that CAR-T cell activation and proliferation is significantly impaired in Matrigel and BME, in contrast to NFC. ConclusionsOur findings highlight the impact of hydrogel choice on (CAR-)T cell behavior, with direct implications for preclinical immunotherapy testing. In contrast to Matrigel and BME, NFC offers a chemically-defined 3D environment where T cell function is preserved. Key messagesO_ST_ABSWhat is already known on this topicC_ST_ABSIn 3D (preclinical) tumor-killing assays for evaluating engineered T cell cytotoxicity, the surrounding matrix can influence immune cell phenotype and function, potentially skewing T cell activity. Basement membrane hydrogels such as Matrigel and basement membrane extract (BME), widely used as scaffolds for 3D culture, are inherently heterogeneous and contain extracellular matrix components that can influence lymphocyte function. What this study addsHere, we show that (CAR-)T cell function is significantly reduced in Matrigel and BME as compared to standard (2D) culture conditions. In contrast, (CAR-)T cell activity is preserved in synthetic nanofibrillar cellulose (NFC) gels. Importantly, murine T cells spontaneously acquire a Treg phenotype in Matrigel and BME. T cell proliferation and cytokine secretion are >10-fold lower in Matrigel than in NFC. Similarly, CAR-T cell survival and expansion are 10-fold higher in NFC than in Matrigel or BME. How this study might affect research, practice or policyWe report that the intrinsic cytotoxic and proliferative potential of (CAR-)T cells can be underestimated when performing assays in 3D cultures based on Matrigel or BME. As an alternative, we suggest the use of chemically defined synthetic gels, and we show that nanofibrillar cellulose hydrogels are suitable 3D matrices for preserving T cell phenotype and activation.

immunology↗

bioRxiv2024

Tumor-derived colorectal cancer organoids induce a unique Treg cell population through direct modulation of CD4+ T cell differentiation.

In colorectal cancer (CRC), increased numbers of tumor-infiltrating CD4+ regulatory T (Treg) cells correlate with tumor development and immunotherapy failure, leading to poor prognosis. However, the molecular and cellular mechanisms governing Treg recruitment, expansion, or differentiation remain unclear. Here, we developed an in vitro co-culture system to assess the capacity of CRC tumors to directly modulate Treg cell differentiation. CD4+ T cells from Foxp3eGFP mice were co-cultured with murine tumor-derived CRC organoids, resulting in a significant increase in Treg cell numbers. This induction of Treg cells was not due to increased proliferation, but rather through differentiation of CD4+ T cells in a TGF{beta}-dependent manner. Human CRC tumor organoids similarly induced Treg cells that exhibited enhanced suppressive capacity compared to TGF{beta}-induced Treg cells. RNA-sequencing analysis identified distinct transcriptional profiles between CRC organoid-induced Treg cells and TGF{beta}-induced Treg cells, with upregulation of key functional signature genes linked to CRC Treg cells in vivo. High expression of genes upregulated in CRC organoid-induced Treg cells correlates with shorter progression free interval and overall survival of CRC patients, highlighting their prognostic potential. Taken together, CRC tumor organoids drive CD4+ differentiation to Treg cells with a phenotype resembling tumor-infiltrating Treg cells. This model can be applied to both understand the molecular mechanisms by which tumors can directly modulate CD4+ T cell differentiation and identify approaches to disrupt Treg cell function and stimulate anti-tumor immunity.

immunology↗