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Calabrese, D. R.

Publications and source records attributed to Calabrese, D. R..

6 recordsLinked to original sources

Tracing cell communication programs across conditions at single cell resolution with CCC-RISE

Cell-cell communication (CCC) mediates coordinated cellular activities that vary dynamically across time, location, and biological context. While various tools exist to infer CCC, they typically aggregate data according to pre-defined cell types, obscuring critical single-cell heterogeneity. Furthermore, because signaling pathways and cell populations operate in a coordinated manner, an integrative analytical approach is essential. To address these challenges, we developed CCC-RISE, an extension of the tensor-based method Reduction and Insight in Single-cell Exploration (RISE). CCC-RISE identifies integrative patterns of single-cell variation by deconvolving communication into interpretable modules defined by unique sender cells, receiver cells, ligands, and condition associations. We applied this framework to a COVID-19 cohort with varying disease severity and a lung transplant cohort with acute allograft dysfunction. In both contexts, CCC-RISE successfully identified disease-relevant communication programs and traced them to specific cellular subpopulations, often crossing conventional cell-type boundaries. This approach offers a robust pipeline enabling the identification of disease-relevant signaling subpopulations that are invisible to aggregate methods. HighlightsO_LICCC-RISE enables integrative analysis of cell-cell communication across multiple conditions at single-cell resolution C_LIO_LICCC-RISE deconvolves signaling patterns into modules defined by their sender cells, receiver cells, LR pairs, and experimental conditions/samples C_LIO_LIAnalysis at single-cell resolution uncovers signaling activity within and across conventional cell types C_LI

systems biology↗

FcεR1γ-based Activating Chimeric Antigen Receptors enhanced Natural Killer cell function against HLA-E+ cells

Fc{varepsilon}R1{gamma} is a transmembrane adaptor protein regulating NKp30, NKp46, and CD16 expression and function in human NK cells. HLA-E expression by cancer cells suppresses NK cell function through interaction with NKG2A. Here, we engineered human NK cells to express a modified Fc{varepsilon}R1{gamma} with a 4-1BB co-stimulatory motif. Fc{varepsilon}R1{gamma}41BB expression led to upregulation of NKp30, NKp46, and CD16 expression and enhanced NKp30 and CD16-mediated target cell lysis. Against cells expressing HLA-E, Fc{varepsilon}R1{gamma}41BB improved NK cell lytic function relative to Fc{varepsilon}R1{gamma}. We then generated an CD19ScFv-CD8hinge-Fc{varepsilon}R1{gamma}41BB(TM-IC) CAR (FCRG10). Engineering human NK cells to express FCRG10 led to upregulation of NKp30 and CD16, and improved NK cell-mediated cytotoxicity against cells co-expressing B7H6, CD19, and HLA-E relative to NK cells expressing the conventional CD19CAR41BB-CD3{zeta} with a CD8 transmembrane domain. Our results indicate that modification of Fc{varepsilon}R1{gamma} enhanced NK cell lytic function mediated by several activating receptors and improved CAR NK cell response in conditions favoring NK cell suppression by HLA-E. Our work may contribute to NK cell-based cancer immunotherapy mediated by co-recognition of stress-induced ligands, antibody-coated cells, and tumor-associated antigens.

immunology↗

Impaired complement regulation drives chronic lung allograft dysfunction after lung transplantation.

A greater understanding of chronic lung allograft dysfunction (CLAD) pathobiology, the primary cause of mortality after lung transplantation, is needed to improve outcomes. The complement system links innate to adaptive immune responses and is activated early post-lung transplantation to form the C3 convertase, a critical enzyme that cleaves the central complement component C3. We hypothesized that LTx recipients with a genetic predisposition to enhanced complement activation have worse CLAD-free survival mediated through increased adaptive alloimmunity. We interrogated a known functional C3 polymorphism (C3R102G) that increases complement activation through impaired C3 convertase inactivation in two independent LTx recipient cohorts. C3R102G, identified in at least one out of three LTx recipients, was associated with worse CLAD-free survival, particularly in the subset of recipients who developed donor-specific antibodies (DSA). In a mouse orthotopic lung transplantation model, impaired recipient complement regulation resulted in more severe obstructive airway lesions when compared to wildtype controls, despite only moderate differences in graft-infiltrating effector T cells. Impaired complement regulation promoted the intragraft accumulation of memory B cells and antibody-secreting cells, resulting in increased DSA levels. In summary, genetic predisposition to complement activation is associated with B cell activation and worse CLAD-free survival. BRIEF SUMMARYLung transplant recipients genetically predisposed to impaired complement regulation demonstrate worse chronic rejection-free survival. This phenotype is associated with intragraft B cell-activation and donor-specific antibodies.

immunology↗

CITE-seq analysis reveals human cytomegalovirus and diabetes-associated adaptive NK cell alterations in cardiovascular disease.

Coronary artery disease (CAD) is a leading cause of mortality worldwide with Diabetes and human cyto-megalovirus (HCMV) infection as risk factors. CADs influence on human NK cells is not well characterized. CITE-seq analysis of a CAD cohort of 61 patients revealed distinctly higher NK cell SPON2 expression and lower IFNG expression in severe CAD patients. Interestingly, HCMV+ patients displayed lower SPON2 ex-pression while diabetes status reversed the HCMV effect. Diabetes led to diminished adaptive Fc{varepsilon}RI{gamma}-/low NK cell frequencies and was associated with a higher PBMC IL15/TGFB transcript ratio, while TGFB in-creased in severe CAD. SPON2 expression corresponded to changes in conventional vs. adaptive NK cell frequencies, and SPON2/IFNG ratio decreased in inflamed plaque tissue with an increased adaptive NK cell gene signature and was increased in severe CAD patients. Our results indicate that the SPON2/IFNG ra-tio and adaptive NK cell gene signature associated with stenosis severity or inflammation in CAD.

immunology↗

Investigating the NRAS 5' UTR as a Target for Small Molecules

Neuroblastoma RAS (NRAS) is an oncogene that is deregulated and highly mutated in cancers including melanomas and acute myeloid leukemias. Constitutively activated NRAS induces the MAPK and AKT signaling pathways and leads to uncontrolled proliferation and cell growth, making it an attractive target for small molecule inhibition. Like all RAS-family proteins, it has proven difficult to identify small molecules that directly inhibit the protein. An alternative approach would involve targeting the NRAS mRNA. The 5' untranslated region (5' UTR) of the NRAS mRNA is reported to contain a G-quadruplex (G4) that regulates translation of NRAS mRNA. Stabilizing the G4 structure with small molecules could reduce NRAS protein expression in cancer cells by impacting translation. Here we report a novel class of small molecule that binds to the G4 structure located in the 5' UTR of the NRAS mRNA. We used a small molecule microarray (SMM) screen to identify molecules that selectively bind to the NRAS-G4. Biophysical studies demonstrated that compound 18 binds reversibly to the NRAS-G4 structure with submicromolar affinity. A Luciferase based reporter assay indicated that 18 inhibits the translation of NRAS via stabilizing the NRAS-G4 in vitro but showed only moderate effects on the NRAS levels in cellulo. Rapid Amplification of cDNA Ends (RACE), RT-PCR analysis on 14 different NRAS-expressing cell lines, coupled with analysis of publicly available CAGE seq experiments, revealed that predominant NRAS transcript does not possess the G4 structure. Further analysis of published rG4 and G4 sequencing data indicated the presence of G4 structure in the promoter region of NRAS gene (DNA) but not in the mRNA. Thus, although many NRAS transcripts lack a G4 in many cell lines the broader concept of targeting folded regions within 5 UTRs to control translation remains a highly attractive strategy and this work represents an intriguing example of transcript heterogeneity impacting targetability.

biochemistry↗

Natural Killer cell division regulates FcεRIγ expression downstream of mTOR activity

The expansion of human Fc{varepsilon}RI{gamma}-/low (FcR{gamma}-/low) natural killer (NK) cells accrues during viral infections; however, the molecular mechanisms regulating FcR{gamma} expression is not well defined and can have implication for host protection and NK cell immunotherapy. Our analysis of NK cell subsets in lung transplant patients during rapamycin treatment revealed significantly lower FcR{gamma} levels in the NK cell population. Moreover, lower FcR{gamma} levels in healthy donors were associated with low mTORC1/C2 activity and low T-bet expression. Cell division suppression by rapamycin or TGF{beta} suppressed FcR{gamma} upregulation during IL-2 receptor stimulation, whereas promoting NK cell division by co-inhibiting FOXO1 activity restored FcR{gamma} upregulation. These results suggest that the human FcR{gamma}-/low NK cell phenotype is associated with cell division suppression and reduced mTOR activity.

immunology↗