Neutrophils, a primary type of immune cell, play critical roles in numerous biological processes. Both umbilical cord blood (UCB) and peripheral blood are rich in neutrophils. UCB is more abundant than peripheral blood, with cells generally at a more immature stage. However, comparative data between these two cell sources is lacking. This study aims to elucidate differences between UCB-derived neutrophils (UCBN) and peripheral blood-derived neutrophils (PBN). UCBN and PBN were isolated from fresh human umbilical cord blood and peripheral blood, respectively. Transcriptomic profiling was performed and compared against neutrophil RNA from three different donors. Bioinformatics analysis was employed to compare cell phenotypes. A cytokine cocktail (IFN-β, IFN-γ, and LPS) was used to activate UCBN and PBN in vitro. A united multi-omic approach, combining transcriptomic and proteomic analysis, was followed by experimental validation through flow cytometry, cell killing assays, and proteome profiler array to verify cell functions. Transcriptomic analysis revealed that the most upregulated genes in freshly isolated umbilical cord blood neutrophils (UCBN) compared to peripheral blood neutrophils (PBN) predominantly involve neutrophil activation and cell-killing functions. Validation through flow cytometry and cell-killing experiments demonstrated that highly viable UCBN exhibited significantly stronger ovarian tumor cell-killing activity in vitro compared to PBN. Both transcriptomic and proteomic analyses indicated that the primary upregulated genes in activated UCBN are chiefly involved in biological processes related to the regulation of cytokine secretion. Integrative multi-omic analysis, including a proteome profiler array, confirmed that UCBN indeed secrete elevated levels of cytokines. In conclusion: UCBN shows higher viability and cellular activity compared with PBN, particularly in tumor cell-killing and cytokine secretion.
AJCR Copyright © 2024.

Genes limiting T cell antitumor activity may serve as therapeutic targets. It has not been systematically studied whether there are regulators that uniquely or broadly contribute to T cell fitness. We perform genome-scale CRISPR-Cas9 knockout screens in primary CD8 T cells to uncover genes negatively impacting fitness upon three modes of stimulation: (1) intense, triggering activation-induced cell death (AICD); (2) acute, triggering expansion; (3) chronic, causing dysfunction. Besides established regulators, we uncover genes controlling T cell fitness either specifically or commonly upon differential stimulation. Dap5 ablation, ranking highly in all three screens, increases translation while enhancing tumor killing. Loss of Icam1-mediated homotypic T cell clustering amplifies cell expansion and effector functions after both acute and intense stimulation. Lastly, Ctbp1 inactivation induces functional T cell persistence exclusively upon chronic stimulation. Our results functionally annotate fitness regulators based on their unique or shared contribution to traits limiting T cell antitumor activity.
Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.

Functional interactions between cytotoxic T cells and tumor cells are central to anti-cancer immunity. However, our understanding of the proteins involved is limited. Here, we present HySic (hybrid quantification of stable isotope labeling by amino acids in cell culture [SILAC]-labeled interacting cells) as a method to quantify protein and phosphorylation dynamics between and within physically interacting cells. Using co-cultured T cells and tumor cells, we directly measure the proteome and phosphoproteome of engaged cells without the need for physical separation. We identify proteins whose abundance or activation status changes upon T cell:tumor cell interaction and validate our method with established signal transduction pathways including interferon γ (IFNγ) and tumor necrosis factor (TNF). Furthermore, we identify the RHO/RAC/PAK1 signaling pathway to be activated upon cell engagement and show that pharmacologic inhibition of PAK1 sensitizes tumor cells to T cell killing. Thus, HySic is a simple method to study rapid protein signaling dynamics in physically interacting cells that is easily extended to other biological systems.
Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and bone erosions. The glycosylated programmed death-1 (PD-1) receptor plays an important role in regulating immune responses and maintaining tolerance. In this study, we focus on two features observed in RA: impaired PD-1 signalling and Galectin-3 (Gal-3) upregulation. We hypothesize that Gal-3 binds PD-1 and PD-1 ligands, potentially contributing to impaired PD-1 signalling. PD-1 and Gal-3 levels in RA synovial fluid (SF) and plasma were evaluated by ELISA. PD-1 and Gal-3 interaction was examined by Surface Plasmon Resonance and ELISA. PD-1, PD-L1 and Gal-3 expression on mononuclear cells from SF and peripheral blood as well as fibroblast-like synoviocytes were examined by flow cytometry. Effects of Gal-3 and PD-L1 on osteoclast formation was evaluated by tartrate-resistant acid phosphatase assay. We show that Gal-3 binds PD-1 and PD-L1. Results demonstrated high expression of PD-1 and Gal-3 on mononuclear cells, especially from SF. Gal-3 inhibited PD-1 signalling when PD-L1 was present. Furthermore, a role of Gal-3 in osteoclast formation was observed in vitro, both directly but also through PD-1:PD-L1 inhibition. Effects of Gal-3 on the PD-1 signalling axis are proposed to be inhibitory, meaning high Gal-3 levels in the complex synovial microenvironment are not desirable in RA. Preventing Gal-3's inhibitory role on PD-1 signalling could, therefore, be a therapeutic target in RA by affecting inflammatory T cell responses and osteoclasts.
© 2022 The Authors. Scandinavian Journal of Immunology published by John Wiley & Sons Ltd on behalf of The Scandinavian Foundation for Immunology.

h4>Background: /h4> Neutrophils are a main type of immune cells involved in many important processes. During tumor progression neutrophils have manifested both tumor-promoting and inhibiting activities. Human umbilical cord blood (UCB)-derived Neutrophils (UCBN) were reported to have anti-tumor activity with ovarian cancer cell lines in vitro in our previous studies. However, the underlying mechanism remains unclear. This present study aims to uncover mechanisms underlying the inhibitory role of UCBN in ovarian cancer compared with peripheral blood-derived Neutrophils (PBN). h4>Methods: /h4>: UCBN and PBN were isolated from freshly obtained human umbilical cord blood and peripheral blood respectively. Cytokine cocktail (IFN-β, IFN-r, and LPS) were used to activate UCBN and PBN in vitro . Mechnism of activated UCBN anti-tumor were done by multi-omic: transcriptomic and Proteomics analysis, followed by experimental validation with flow cytometry, cell killing assays and proteome profiler array. h4>Results: /h4>: The transcriptomic analysis showed that the top upregulated genes in fresh isolated UCBN compared with PBN mainly focus on neutrophils activation and cell killing. High activity UCBN displayed strong ovarian tumor cell killing activity than PBN in vitro. Transcriptomic and proteomics analysis both revealed that the top upregulated molocules in activated UCBN were mainly involved in biologic processes related to regulation of cytokine secretion. United multi-omic analysis with proteome profiler array, we screened the anti-tumor molecule CCL3, which activated IFN-r related pathway JAK/STAT to killing tumor cells by RNA-seq. h4>Conclusions: /h4>: Hence UCBN may constitute a viable strategy for ovarian cancer immunotherapy.