Biology subjects

Lindblad, K. E.

Publications and source records attributed to Lindblad, K. E..

7 recordsLinked to original sources

bioRxiv2026

B cells sustain tumor-specific CD4 T cells to promote response to PD-1 targeted therapy

Immunotherapy transformed cancer treatment, yet precise correlates of response remain to be defined. While intratumoral follicular helper like (Tfhl) CD4 T cells and IgG1+ B cells have been associated with improved outcomes to PD-1 blockade for hepatocellular carcinoma (HCC), their mechanisms contributing to response are unclear. To address this question, we developed a murine model of HCC and examined CD8, CD4 and B cell responses. Increasing CD4-help sensitizes mice to PD-1 blockade, in a CD4- and CD8-dependent manner. Tumor-specific CD4 T cells contained Tfhl and Th1 populations, and both Bcl6 and T-bet were required for efficacy. Antigen-specific B cells were essential for CD4-helper expansion, yet secretion of antibodies was not required for long-term survival. Thus, B cells are critical for effective immunotherapy, but secreted antibodies are not.

immunology↗

bioRxiv2025

Bacteroidetes promote hepatocellular carcinoma progression and resistance to immunotherapy

Background and AimsGrowing evidence highlight the critical role of the gut microbiome in tumorigenesis and response to immunotherapies. However, the impact of gut microbes on hepatocellular carcinoma (HCC) progression and response to immune-checkpoint blockade (ICB) remains unclear due to the lack of combined preclinical and clinical studies. Approach & ResultsWe performed 16S rRNA of cross-cohort stool samples from 10 HCC responders (R) and 40 non-responders (NR) to ICB at baseline and on-treatment time-points. We identified an enrichment of Bacteroidetes in NR. To study the role of the microbiome in the cancer immune response, we generated an immunogenic mouse model of HCC via hydrodynamic tail-vein injection (HDTVI) of DNA plasmids mimicking common HCC alterations and immunogenicity by expressing model antigens (MYC-lucOS;CTNNB1 tumors). We found that antibiotic (ABX)-induced dysbiosis promoted a pro-tumorigenic effect in the MYC-lucOS;CTNNB1 HCC model by the expansion of a specific Bacteroidetes, Parabacteroides distasonis. Colonization of mice carrying MYC-lucOS;CTNNB1 HCCs with Parabacteroides distasonis confirmed its pro-tumorigenic effect in vivo. Furthermore, we explored the effects of colonizing with microbiotas from patients and showed that microbiota from a NR donor enriched in Bacteroidetes promoted faster tumorigenesis than microbiota from a R donor with reduced Bacteroidetes. We isolated 6 Bacteroidetes species from the NR donor, cultured them, and used them as a cocktail to colonize mice; similarly, mice transplanted with this cocktail showed increased tumorigenesis and reduced survival. ConclusionsThis study identified Bacteroidetes enrichment as a potential biomarker of ICB resistance in HCC and, by using immunogenic mouse models, established that Bacteroidetes abundance influences tumor development.

cancer biology↗

bioRxiv2025

TREM2 macrophages are associated with enhanced response to PD-1 blockade in human hepatocellular carcinoma

Macrophages are known to dampen tumor immunity. However, identifying druggable targets that modulate these cells to improve existing immunotherapies has been limited by a dearth of studies identifying macrophages that associate with pathological response to immune checkpoint blockade. To fulfill this unmet clinical need, we leveraged transcriptional and spatial profiling of specimens collected from a Phase II clinical trial studying neoadjuvant PD-1 blockade in patients with hepatocellular carcinoma (HCC). We determined that the intratumoral abundance of TREM2-expressing macrophages and serological levels of soluble TREM2 are elevated in patients who responded to PD-1 blockade, compared to non-responders. We validated these findings in a second HCC cohort and in the IMbrave150 trial. These highlight the robust potential for TREM2 macrophages to predict therapeutic responses of HCC to immunotherapy. Therefore, our study provides a novel basis for the use of TREM2 macrophages to strategize treatment for patients with HCC to maximize therapeutic benefit.

immunology↗

bioRxiv2024

NOTCH1 drives tumor plasticity and metastasis in hepatocellular carcinoma

Background & AimsLiver cancer, the third leading cause of cancer-related mortality worldwide, has two main subtypes: hepatocellular carcinoma (HCC), accounting the majority of the cases, and cholangiocarcinoma (CAA). Notch pathway primarily regulates the intrahepatic development of bile ducts, which are lined with cholangiocytes, but it can also be upregulated in 1/3 of HCCs. To better understand the role of NOTCH1 in HCC, we developed a novel mouse model driven by activated Notch1 intracellular domain (NICD1) and MYC overexpression in hepatocytes. MethodsUsing the hydrodynamic tail-vein injection method for establishing primary liver tumors, we generated a novel murine model of liver cancer harboring MYC overexpression and NOTCH1 activation. We characterized this model histopathologically as well as transcriptomically, utilizing both bulk and single cell RNA-sequencing. We also performed functional experiments using monoclonal antibodies. ResultsMYC;NICD1 tumors displayed a combined HCC-CCA phenotype with temporal plasticity. At early time-points, histology was predominantly "cholangiocellular", which then progressed to mainly "hepatocellular". The "hepatocellular" component was enriched in mesenchymal genes and gave rise to lung metastasis. Metastatic cells were enriched in the TGFB and VEGF pathways and their inhibition significantly reduced the metastatic burden. ConclusionsOur novel mouse model uncovered NOTCH1 as a driver of temporal plasticity and metastasis in HCC, the latter of which is, in part, mediated by angiogenesis and TGF{beta} pathways. Impact and ImplicationsThis study develops a novel murine model of NOTCH1-driven liver cancer, an understudied oncogene in HCC. Using this model, we show that NOTCH1 drives plasticity in HCC and metastasis to the lungs that can be therapeutically targeted through inhibition of VEGF and TGF{beta} pathways. HighlightsO_LINOTCH1 activation in combination with MYC overexpression drives combined HCC-CCA. C_LIO_LINOTCH1 activation in hepatocytes drives temporal plasticity. C_LIO_LINOTCH1 activation drives metastasis of HCC cells to the lungs, but not of CCA cells. C_LIO_LIAngiogenesis and TGF{beta} pathways mediate NOTCH1-induced lung metastasis. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=93 SRC="FIGDIR/small/619856v2_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@143c866org.highwire.dtl.DTLVardef@119ddb6org.highwire.dtl.DTLVardef@12ad951org.highwire.dtl.DTLVardef@2160b8_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2022

The novel compensatory reciprocal interplay between neutrophils and monocytes drives cancer progression

Myeloid cells comprise the majority of immune cells in tumors, contributing to tumor growth and therapeutic resistance. Incomplete understanding of myeloid cells response to tumor driver mutation and therapeutic intervention impedes effective therapeutic design. Here, by leveraging CRISPR/Cas9-based genomic editing, we generated a mouse model that is deficient of all monocyte chemoattractant proteins (MCP). Using this strain, we effectively abolished monocyte infiltration in glioblastoma (GBM) and hepatocellular carcinoma (HCC) murine models, which were enriched for monocytes or neutrophils, respectively. Remarkably, eliminating monocyte chemoattraction invokes a significant compensatory neutrophil influx in GBM, but not in HCC. Single-cell RNA sequencing revealed that intratumoral neutrophils promoted proneural-to-mesenchymal transition in GBM, and supported tumor aggression by facilitating hypoxia response via TNF production. Importantly, genetic or pharmacological inhibiting neutrophil in HCC or qMCP-KO GBM extended the survival of tumor-bearing mice. Our findings emphasize the importance of targeting both monocytes and neutrophils simultaneously for cancer immunotherapy. In BriefEliminating monocyte chemoattraction invokes compensatory neutrophil influx in tumor, and vice versa, rendering current myeloid-targeted therapies ineffective. Using genetic and pharmacological approaches combined with novel mouse models of GBM and HCC, we provide credence advocating for combinational therapies aiming at inhibiting both monocytes and neutrophils simultaneously. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=153 SRC="FIGDIR/small/500690v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@bbbae5org.highwire.dtl.DTLVardef@eb3eecorg.highwire.dtl.DTLVardef@702696org.highwire.dtl.DTLVardef@f54734_HPS_FORMAT_FIGEXP M_FIG C_FIG Highlights* Blocking monocyte chemoattraction results in increased neutrophil infiltration. * Increased neutrophil recruitment induces GBM PN to MES transition. * Inhibiting neutrophil infiltration in monocyte-deficient tumors improves mouse GBM survival. * Blocking neutrophil, but not monocyte, infiltration in HCC prolongs mouse survival.

immunology↗

bioRxiv2018

Molecular measurable residual disease testing of blood during AML cytotoxic therapy for early prediction of clinical response

AbstractO_ST_ABSPURPOSEC_ST_ABSMeasurable residual disease (MRD) testing after initial chemotherapy treatment can predict relapse and survival in AML. However, it has not been established if repeat molecular or genetic testing during chemotherapy can offer information regarding the chemotherapy sensitivity of the leukemic clone.\n\nPATIENTS AND METHODSBlood from 45 adult AML patients at day 1 and 4 of induction (n = 35) or salvage (n = 10) cytotoxic chemotherapy was collected for both quantitative real-time PCR (qPCR) assessment (WT1) and next generation sequencing (NGS, >500x depth) of 49 gene regions recurrently mutated in MDS/AML.\n\nRESULTSThe median age was 62 (23-78); 42% achieved a complete response. WT1 was overexpressed in most patients tested but was uninformative for very early MRD assessment. A median of 4 non-synonymous variants (range 0-7) were detected by DNA sequencing of blood on day 1 of therapy (median VAF: 29%). Only two patients had no variants detectable. All mutations remained detectable in blood on day 4 of intensive chemotherapy and remarkably the ratio of mutated to wild-type sequence was often maintained. This phenomenon was not limited to variants in DNMT3A, TET2 and ASXL1. The kinetics of NPM1 and TP53 variant burden early during chemotherapy appeared to be exceptions and exhibited consistent trends in this cohort.\n\nCONCLUSIONSMolecular testing of blood on day 4 of chemotherapy is not predictive of clinical response in AML. The observed stability in variant allele frequency suggests that cytotoxic therapy may have a limited therapeutic index for clones circulating in blood containing these mutations. Further validation is required to confirm the utility of monitoring NPM1 and TP53 kinetics in blood during cytotoxic therapy.

cancer biology↗

bioRxiv2018

Human Bone Marrow Assessment by Single Cell RNA Sequencing, Mass Cytometry and Flow Cytometry

New techniques for single-cell analysis have led to insights into hematopoiesis and the immune system, but the ability of these techniques to cross-validate and reproducibly identify the biological variation in diverse human samples is currently unproven. We therefore performed a comprehensive assessment of human bone marrow cells using both single-cell RNA sequencing and multiparameter flow cytometry from twenty healthy adult human donors across a broad age range. These data characterize variation between healthy donors as well as age-associated changes in cell population frequencies. Direct comparison of techniques revealed discrepancy in the quantification of T lymphocyte and natural killer cell populations. Orthogonal validation of immunophenotyping using mass cytometry demonstrated good correlation with flow cytometry. Technical replicates using single-cell RNA sequencing matched robustly, while biological replicates showed variation. Given the increasing use of single-cell technologies in translational research, this resource serves as an important reference dataset and highlights opportunities for further refinement.

immunology↗