Biology subjects

Eldering, E.

Publications and source records attributed to Eldering, E..

4 recordsLinked to original sources

bioRxiv2026

Single-cell characterization of 3D CLL spheroid model that recapitulates lymph node microenvironment-driven phenotypes and in vivo drug responses to ibrutinib

Lymph node (LN) microenvironmental signals promote chronic lymphocytic leukemia (CLL) cell survival, proliferation, and treatment resistance. We previously developed a 3D culture model that recapitulates key features of this protective LN niche. Using single-cell RNA sequencing of ex vivo paired peripheral blood and LN samples, together with matched patient-derived CLL spheroids, we investigated how microenvironmental cues shape CLL phenotypes and their response to ibrutinib. A total of 3 functional CLL states (resting, activated, proliferating) were identified, with expanded populations of activated and proliferating subsets in 3D cultures. After 5 days of in vitro ibrutinib treatment, CLL cells shifted toward a resting phenotype, reflecting published responses in patients at 6 months. Activated CLL cells showed relative resistance to ibrutinib, associated with TLR9-MALT1-MYC pathway activation. The 3D model recapitulated tissue-specific T cell phenotypes observed in patients, and computational analyses predicted several T-to-CLL cell-mediated interactions supporting the LN niche. Collectively, these data reveal distinct ibrutinib responses among CLL subsets and establish the 3D model as a physiologically relevant platform.

cancer biology↗

bioRxiv2026

Glutamine-driven mTORC1 activity enforces glycolytic bias, hyperactivation and aberrant proliferation in T cells in chronic B-cell leukemia

T-cell metabolic dysfunction is increasingly recognized as a hallmark of poor antitumor responses. Still, how distinct metabolic states shape T-cell function and which signaling pathways sustain them remains unclear. Here, we show that T cells from patients with chronic lymphocytic leukemia (CLL) adopt a hyperactivated phenotype characterized by high cytokine production, aberrant proliferation and a bias toward glycolysis, supported by sustained glutamine-driven mTORC1 activity. In parallel, T cells from these patients display alterations in mitochondrial network and cristae architecture, which further limit oxidative phosphorylation. mTORC1 inhibition reduces glucose dependence, restores mitochondrial metabolic engagement and normalizes T-cell activation and proliferation. Together, these findings identify metabolic disbalance as a central contributor to the hyperactivated state of T cells in CLL. We propose a model in which reduced OXPHOS reflects both mitochondrial defects that pre-exist in T cells from patients before TCR engagement, and a failure to engage mitochondrial metabolism upon activation supported by the actionable target mTORC1. HighlightsO_LIT cells from patients with chronic lymphocytic leukemia display high cytokine production and excessive division cycles upon CD3/28 engagement. C_LIO_LImTORC1-sustained glycolysis and defects in mitochondrial structure compromise OXPHOS in hyperactivated T cells. C_LIO_LIExogenous glutamine uptake sustains non-lysosomal mTORC1 activity in T cells. C_LI

immunology↗

bioRxiv2024

Disruption of basal CXCR4 oligomers impairs oncogenic properties in lymphoid neoplasms

The chemokine receptor CXCR4 is overexpressed in many cancers and contributes to pathogenesis, disease progression, and resistance to therapies. CXCR4 is known to form oligomers, but the potential functional relevance in malignancies remain elusive. Using a newly established nanobody-based BRET method, we demonstrate that oligomerization of endogenous CXCR4 on lymphoid cancer cell lines correlates with enhanced expression levels. Specific disruption of CXCR4 oligomers reduced basal cell migration and pro-survival signaling via changes in the phosphoproteome, indicating the existence of basal CXCR4-oligomer-mediated signaling. Oligomer disruption also inhibited growth of primary CLL 3D spheroids and sensitized primary malignant cells to clinically used Bcl-2 inhibitor venetoclax. Given its limited efficacy in some patients and the ability to develop resistance, sensitizing malignant B-cells to venetoclax is of clinical relevance. Taken together, we established a new, non-canonical and critical role for CXCR4 oligomers in lymphoid neoplasms and demonstrated that selective targeting thereof has clinical potential. Significance statementClass A GPCRs, including the chemokine receptor CXCR4, can form oligomers, but their functional relevance remains poorly understood. This study provides evidence for the role of basal CXCR4 oligomers in lymphoid neoplasms, where they drive pro-survival signaling, migration, and tumor growth. We use a novel nanobody-based BRET method to demonstrate that endogenous CXCR4 constitutively oligomerizes in lymphoid cancer cells, correlating with receptor expression levels. Pharmacological disruption of these oligomers reduces tumor- associated signaling, impairs spheroid growth, and sensitizes patient-derived malignant cells to the apoptosis-inducing drug Venetoclax. Since CXCR4 is frequently overexpressed and potentially clustered in various malignancies, this work offers broader implications for enhancing treatment efficacy, overcoming drug resistance, and potentially reducing side effects across multiple cancer types.

biochemistry↗

bioRxiv2023

In vitro lymph node-mimicking 3D model displays long-term T cell-dependent CLL proliferation and survival

Chronic lymphocytic leukemia (CLL) cells are highly dependent on microenvironmental cells and signals. The lymph node (LN) is the critical site of in vivo CLL proliferation and development of resistance to both chemotherapy and targeted agents. We present a new model that incorporates key aspects of the CLL LN which enables investigation of CLL cells in the context of a protective niche. We describe a 3D in vitro culture system utilizing ultra-low attachment (ULA) plates to create spheroids of CLL cells derived from peripheral blood (PB). Starting from CLL:T cell ratios as observed in LN samples, CLL activation was induced by either direct stimulation and/or indirectly via T cells. Compared to 2D cultures, 3D cultures promoted CLL proliferation in a T cell-dependent manner, and enabled expansion for up to 7 weeks, including the formation of follicle-like structures after several weeks of culture. Addition of LN-derived stromal cells further enhanced the proliferative capacity. This model enables high-throughput drug screening, of which we describe response to Btk inhibition, venetoclax resistance, and T cell-mediated cytotoxicity as examples. In summary, we present the first LN-mimicking in vitro 3D culture for primary CLL, which enables readouts such as real-time drug screens, kinetic growth assays and spatial localization. This is the first in vitro CLL system that allows testing of response and resistance to venetoclax and Btk inhibitors in the context of the tumor microenvironment, thereby opening up new possibilities for clinically useful applications.

cancer biology↗