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Biology subjects

Ward, S. C.

Publications and source records attributed to Ward, S. C..

3 recordsLinked to original sources

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↗

MARQO pipeline resolves multiparametric cellular and spatial organization in cancer tissue lesions

Multiplex immunostaining analysis remains fragmented, underperforming, and labor-intensive despite tissue proteomic methodologies achieving ever-increasing marker complexity. Here we propose an open-source, semi-supervised automated pipeline that streamlines start-to-finish, single-cell resolution analysis of whole-slide tissue, named Multiplex-imaging Analysis, Registration, Quantification, and Overlaying (MARQO). We compared and validated MARQO using Multiplex Immunohistochemical Consecutive Staining on a Single Slide (MICSSS) using human tumor and adjacent normal tissue samples. Performance was compared with manually-curated pathologist determinations and quantification of multiple markers. We also optimized MARQO to analyze diverse tissue sizes (whole tissue, biopsy, tissue microarray) and staining approaches (singleplex immunohistochemistry, 20-color multiplex immunofluorescence) to determine marker co-expression patterns in multiple human solid cancer types. Lastly, we validated CD8 T cell enrichment in hepatocellular carcinoma responders to neoadjuvant cemiplimab in a phase II clinical trial, further demonstrating MARQOs ability to provide spatially-resolved in situ mechanisms by providing multiplex whole-slide single-cell resolution data.

immunology↗

Genetic polymorphisms of Leukocyte Immunoglobulin-Like Receptor B3 (LILRB3) gene in African American kidney transplant recipients are associated with post-transplant graft failure

BackgroundAfrican American (AA) kidney transplant recipients exhibit a higher rate of graft loss compared to other racial and ethnic populations, highlighting the need to identify causative factors underlying this disparity. MethodWe analyzed RNA sequences of pretransplant whole blood from subjects followed in three kidney transplant cohorts to identify single nucleotide polymorphisms (SNPs) associated with death censored graft loss (DCGL). We employed a meta-analysis to uncover key transcriptional signatures and pathways associated with the identified SNPs and used single cell RNA to define cellular specificity. We characterized SNP functions using in vitro immunological and survival assays and tested for associations between the identified SNPs and other immune-related diseases using a [~]30,100 subject, electronic health record (EHR)-linked database. ResultsWe uncovered a cluster of four consecutive missense SNPs in the Leukocyte Immunoglobulin-Like Receptor B3 (LILRB3, a negative immune response regulator) gene that strongly associated with DCGL. This LILRB3-4SNPs cluster encodes missense mutations at amino acids 617-618 proximal to a SHP-1/2 phosphatase-binding ITIM motif. LILRB3-4SNPs is specifically enriched within subjects of AA ancestry (8.6% prevalence vs 2.3% in Hispanic and 0.1% in European populations), is not linked to APOL1 G1/G2 alleles, and exhibited a strong association with DCGL. Analysis of PBMC and transplant biopsies from recipients with LILRB3-4SNPs showed evidence of enhanced adaptive immune responsiveness and ferroptosis-associated death in monocytes. Overexpression of the variant allele in THP-1 cells (macrophage line) induced augmented inflammation and ferroptosis, which were attenuated by a ferroptosis inhibitor, verifying a causal link. The LILRB3-4SNPs also associated with multiple systemic and organ-specific immune-related diseases in AAs, consistent with conferring a broadly relevant immune function. Conclusionthe LILRB3-4SNPs represent a functionally important, distinct genetic risk factor for kidney transplant outcome and development/severity of other immune-related diseases in patients of AA ancestry. Pharmacological targeting of ferroptosis should be tested to prevent or treat these disease processes in AA recipients carrying LILRB3-4SNPs.

genetics↗