Biology subjects

Zulueta, J.

Publications and source records attributed to Zulueta, J..

4 recordsLinked to original sources

bioRxiv2026

IFNγ and proinflammatory cytokines cooperatively license astrocytes to support antigen-dependent CD4+ T cell restimulation

We report that type 2 interferon with proinflammatory cytokines induces astrocytes to express multiple components required for attraction of and antigen presentation to CD4+ T cells via MHC-II molecules. Re-analysis of astrocyte-enriched single-cell sequencing from bacterial mimetic-injected mice revealed a transcriptionally distinct interferon-responsive astrocyte population enriched for antigen-presentation-associated genes 24 hours after peripheral immune challenge. In vivo, we identify MHC-II+GFAP+ astrocytes localized to the surface of the brain across multiple mouse models of neuroinflammation and in human neurological disease tissue. In a pure in vitro culture system, astrocytes stimulated with IFN{gamma} and proinflammatory cytokines express MHC-II, costimulatory molecules and lymphocyte-recruiting chemokines, and support rapid antigen-dependent expansion of previously activated CD4+ T cells. Using human iPSC-derived CNS cultures, we additionally show induction of antigen-presentation-associated machinery in human astrocytes following inflammatory cytokine stimulation. Rather than inferring function solely from marker expression, we assessed astrocyte-supported T cell restimulation in vitro and separately characterized the emergence of antigen-presentation-associated astrocytes in vivo at neuroimmune interfaces during inflammation in mice and humans. Together, these findings support a conserved role for cytokine-stimulated astrocytes in expressing antigen-presentation-associated machinery and, in vitro, supporting antigen-dependent restimulation/expansion of CD4+ T cells under inflammatory conditions.

neuroscience↗

bioRxiv2026

The complete genome of the KOLF2.1J reference iPSC line

While induced pluripotent stem cells (iPSCs) have gained popularity in studying neurodegenerative diseases, the heterogeneity of stem cells used across studies impacts cross-study comparison. The iPSC Neurodegenerative Disease Initiative (iNDI) selected the KOLF2.1J cell line and prioritized its use as a reference standard for studying the effects of pathogenic variants on cell biology due to its stability and neutral neurodegenerative disease genetic risk. This cell line, and its derivatives expressing over 100 variants related to Alzheimers disease, Parkinsons disease, and other neurological diseases, are available for academic and industry access. Current genomic data analyses are limited by the use of a human reference genome that does not capture the complete genetic background of a given iPSC line. While in the future this issue may be partially mitigated by the creation of a comprehensive human pangenome, previous work has shown that generating custom genomes is of value both to characterize the variation present and to serve as a more appropriate genomic reference. Here, we generated and characterized a custom complete genome assembly from KOLF2.1J. Mapping of sequencing reads to a personalized diploid assembly results in more comprehensive mapping compared to traditional linear references (i.e GRCh38). In addition, we provide a comprehensive custom gene annotation along with isoform expression and differential methylation analyses across multiple cell types. The assembly and all additional data is browsable and publicly available. This resource will enable more accurate investigation of the KOLF2.1J cell line and any genomics data generated compared to using traditional generalized references, while also serving as a foundational approach for establishing custom reference assemblies for other high-value iPSC lines.

genomics↗

bioRxiv2024

Airway basal stem cells are necessary for the maintenance of functional intraepithelial airway macrophages.

Adult stem cells play a crucial role in tissue homeostasis and repair through multiple mechanisms. In addition to being able to replace aged or damaged cells, stem cells provide signals that contribute to the maintenance and function of neighboring cells. In the lung, airway basal stem cells also produce cytokines and chemokines in response to inhaled irritants, allergens, and pathogens, which affect specific immune cell populations and shape the nature of the immune response. However, direct cell-to-cell signaling through contact between airway basal stem cells and immune cells has not been demonstrated. Recently, a unique population of intraepithelial airway macrophages (IAMs) has been identified in the murine trachea. Here, we demonstrate that IAMs require Notch signaling from airway basal stem cells for maintenance of their differentiated state and function. Furthermore, we demonstrate that Notch signaling between airway basal stem cells and IAMs is required for antigen-induced allergic inflammation only in the trachea where the basal stem cells are located whereas allergic responses in distal lung tissues are preserved consistent with a local circuit linking stem cells to proximate immune cells. Finally, we demonstrate that IAM-like cells are present in human conducting airways and that these cells display Notch activation, mirroring their murine counterparts. Since diverse lung stem cells have recently been identified and localized to specific anatomic niches along the proximodistal axis of the respiratory tree, we hypothesize that the direct functional coupling of local stem cell-mediated regeneration and immune responses permits a compartmentalized inflammatory response.

cell biology↗

bioRxiv2022

Lung spatial profiling reveals a T cell signature in COPD patients with fatal SARS-CoV-2 infection

RationalePeople with pre-existing lung diseases like chronic obstructive pulmonary disease (COPD) are more likely to get very sick from SARS-CoV-2 disease 2019 (COVID-19), but an interrogation of the immune response to COVID-19 infection, spatial throughout the lung structure is lacking in patients with COPD. ObjectivesTo profile the immune microenvironment of lung parenchyma, airways, and vessels of never- and ever-smokers with or without COPD, whom all died of COVID-19, using spatial transcriptomic and proteomic profiling. FindingsThe parenchyma, airways, and vessels of COPD patients, compared to control lungs had: 1) significant enrichment for lung resident CD45RO+ memory T cells; 2) downregulation of genes associated with T cell antigen-priming and memory T cell differentiation; 3) higher expression of proteins associated with SARS-CoV-2 entry and major receptor ubiquitously across the ROIs and in particular the lung parenchyma, despite similar SARS-CoV-2 structural gene expression levels. ConclusionsThe lung parenchyma, airways, and vessels of COPD patients have increased T-lymphocytes with a blunted memory T cell response and a more invasive SARS-CoV-2 infection pattern, and may underlie the higher death toll observed with COVID-19.

immunology↗