Ryo Hisamune ¹, Kazuma Yamakawa ¹, Katsuhide Kayano ¹, Noritaka Ushio ¹, Takeshi Wada ², Kohei Taniguchi ³, Akira Takasu ¹ Acute Med Surg. . 2024 Aug 29;11(1):e70003. doi: 10.1002/ams2.70003. eCollection 2024 Jan-Dec.

Aims: SARS-CoV-2 causes systemic immune dysfunction, leading to severe respiratory dysfunction and multiorgan dysfunction. Granulocyte and monocyte adsorptive apheresis (GMA) therapy is designed to regulate an excessive inflammatory response and has been proposed as a potential therapeutic strategy for coronavirus disease 2019 (COVID-19). We aimed to investigate a targeted subset of granulocytes and monocytes to be removed after GMA therapy in patients with severe COVID-19 infection.

Methods: We established an ex vivo experimental system to study the effects of GMA. Blood samples were collected into EDTA-treated tubes and a mixture of blood samples and cellulose acetate beads was used in GMA. After GMA, blood samples were removed, and the granulocyte and monocyte subtypes before and after GMA were determined by CyTOF mass cytometry. To analyze mass cytometry data with a self-organizing map, hierarchical clustering was used to determine the appropriate number of metaclusters from t-distributed stochastic neighbor embedding.

Results: We included seven patients with severe COVID-19 and four age- and sex-matched volunteers. Granulocyte subsets removed by GMA strongly expressed CD11b, CD16, and CD66b, and weakly expressed CD11c, consistent with mature and activated neutrophils. Monocyte subsets strongly expressed CD14, weakly expressed CD33 and CD45RO, and did not express CD16. These subsets were indicated to promote the release of inflammatory cytokines and activate T cells.

Conclusions: The identification of the granulocyte and monocyte subsets removed after GMA in patients with severe COVID-19 may help explain the potential mechanism underlying the effectiveness of GMA in COVID-19 and other inflammatory diseases.

Xiping Liao ^# 1 2, Ji Liu ^# 3, Xiaolong Guo ¹, Ruiping Meng ¹, Wei Zhang ¹, Jianyun Zhou ¹, Xia Xie ^1 2, Hongli Zhou ¹

J Inflamm Res. 2024 May 13:17:2897-2914. doi: 10.2147/JIR.S450801. eCollection 2024.

Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic disease resulting from the interaction of various factors such as social elements, autoimmunity, genetics, and gut microbiota. Alarmingly, recent epidemiological data points to a surging incidence of IBD, underscoring an urgent imperative: to delineate the intricate mechanisms driving its onset. Such insights are paramount, not only for enhancing our comprehension of IBD pathogenesis but also for refining diagnostic and therapeutic paradigms. Monocytes, significant immune cells derived from the bone marrow, serve as precursors to macrophages (Mφs) and dendritic cells (DCs) in the inflammatory response of IBD. Within the IBD milieu, their role is twofold. On the one hand, monocytes are instrumental in precipitating the disease’s progression. On the other hand, their differentiated offsprings, namely moMφs and moDCs, are conspicuously mobilized at inflammatory foci, manifesting either pro-inflammatory or anti-inflammatory actions. The phenotypic spectrum of these effector cells, intriguingly, is modulated by variables such as host genetics and the subtleties of the prevailing inflammatory microenvironment. Notwithstanding their significance, a palpable dearth exists in the literature concerning the roles and mechanisms of monocytes in IBD pathogenesis. This review endeavors to bridge this knowledge gap. It offers an exhaustive exploration of monocytes’ origin, their developmental trajectory, and their differentiation dynamics during IBD. Furthermore, it delves into the functional ramifications of monocytes and their differentiated progenies throughout IBD’s course. Through this lens, we aspire to furnish novel perspectives into IBD’s etiology and potential therapeutic strategies.

Salma A Rizo-Téllez ¹, János G Filep ¹

Am J Physiol Cell Physiol . 2024 Mar 1;326(3):C661-C683. doi: 10.1152/ajpcell.00652.2023. Epub 2024 Jan 8.

Neutrophils, the most abundant immune cells in human blood, play a fundamental role in host defense against invading pathogens and tissue injury. Neutrophils carry potentially lethal weaponry to the affected site. Inadvertent and perpetual neutrophil activation could lead to nonresolving inflammation and tissue damage, a unifying mechanism of many common diseases. The prevailing view emphasizes the dichotomy of their function, host defense versus tissue damage. However, tissue injury may also persist during neutropenia, which is associated with disease severity and poor outcome. Numerous studies highlight neutrophil phenotypic heterogeneity and functional versatility, indicating that neutrophils play more complex roles than previously thought. Emerging evidence indicates that neutrophils actively orchestrate resolution of inflammation and tissue repair and facilitate return to homeostasis. Thus, neutrophils mobilize multiple mechanisms to limit the inflammatory reaction, assure debris removal, matrix remodeling, cytokine scavenging, macrophage reprogramming, and angiogenesis. In this review, we will summarize the homeostatic and tissue-reparative functions and mechanisms of neutrophils across organs. We will also discuss how the healing power of neutrophils might be harnessed to develop novel resolution and repair-promoting therapies while maintaining their defense functions.

Ronen Sumagin ¹

Am J Pathol . 2024 Jan;194(1):2-12. doi: 10.1016/j.ajpath.2023.10.009. Epub 2023 Nov 2.

Neutrophils [polymorphonuclear leukocytes (PMNs)] execute important effector functions protecting the host against invading pathogens. However, their activity in tissue can exacerbate inflammation and inflammation-associated tissue injury and tumorigenesis. Until recently, PMNs were considered to be short-lived, terminally differentiated phagocytes. However, this view is rapidly changing with the emerging evidence of increased PMN lifespan in tissues, PMN plasticity, and phenotypic heterogeneity. Specialized PMN subsets have been identified in inflammation and in developing tumors, consistent with both beneficial and detrimental functions of PMNs in these conditions. Because PMN and tumor-associated neutrophil activity and the resulting beneficial/detrimental impacts primarily occur after homing to inflamed tissue/tumors, studying the underlying mechanisms of PMN/tumor-associated neutrophil trafficking is of high interest and clinical relevance. This review summarizes some of the key findings from over a decade of work from my laboratory and others on the regulation of PMN recruitment and identification of phenotypically and functionally diverse PMN subtypes as they pertain to gut inflammation and colon cancer.

D. Kioroglu1 , J.L. Cabriada2, U. M. Marigorta1,3, I. Rodríguez-Lago Ueg journal

Volume11, Issue S8 Supplement: 31st United European Gastroenterology Week 2023 October 2023 Pages 799

Introduction: Granulocyte–monocyte apheresis (GMA) is a non-pharmacological therapy approved for the treatment of ulcerative colitis (UC), mainly in steroid-dependent cases. Its mechanism of action is based onthe removal of activated leukocytes, but its exact immunological changes have not been fully described yet. Aims & Methods: Our aim was to characterize the response in the transcriptome at the single-cell resolution level and cell population effects of GMA device. We analysed scRNASeq data from peripheral blood mono-nuclear cells (PBMC) of two UC patients undergoing their first GMA session. Their gene expression profile was compared before (PRE) and one month after (POST) the GMA treatment, from the inflow and outflow lines, respectively. The analytical pipeline included quality control and filtering, cell-type annotation, differential gene expression and pathway enrichment analysis. Results: Two patients with UC (mean age 59 years; both E2) were included.Overall, the cell populations that appear to have been affected by the GMA treatment were natural killer cells and monocytes with both populations being reduced after the treatment. The distribution of the annotated cell-types was 2,369 B cells (PRE:50%, POST:49%), 11,462 CD4+ (PRE:49%,POST:50%) and 8,845 CD8+ T-cells (PRE:51%, POST:48%), 47 dendritic cells (PRE:40%, POST:59%), 3,773 natural killer cells (PRE:54%, POST:45%) and 2,352 monocytes (PRE:59%, POST:40%). Annotation at higher resolution identified 27 cell-types with monocytes being subannotated as 1,972 CD14 (PRE:62%, POST:37%) and 380 CD16 (PRE:48%, POST:51%) monocytes. Differential gene expression analysis identified in total 86 significant genes across six cell-types (CD4+ naive and central memory T-cells, natural killer cells, B intermediate cells, double-negative T-cells and CD14monocytes) with 63% of these genes being downregulated after the GMA treatment. Pathway enrichment analysis identified higher contribution of the double-negative T-cells to the enriching genes. More specifically, after the treatment the double-negative T-cells exhibited upregulation of the NEFL that is associated with the MAPK cascade and downregulation of genes related to immune response and signalling pathways. Regarding the CD14 monocytes, after the GMA treatment we observed significant downregulation of the genes LINC02315, IGHEP1 and IGHE, with the latter being linked to innate immune response pathways. Conclusion: GMA induces a range of modifications in the gene expression profile across different cell types that change the immunological environment of UC patients.

Giorgos Bamias ¹, Evanthia Zampeli ², Eugeni Domènech ³ Expert Rev Gastroenterol Hepatol  2022 Jul 19;1-15. doi: 10.1080/17474124.2022.2100759.

Introduction: Inflammatory bowel disease (IBD) is a chronic immune-mediated disease of the gastrointestinal tract comprising Crohn’s disease (CD) and ulcerative colitis (UC). While any part of the digestive tract can be affected in CD, mucosal inflammation in UC is limited to the colon. Differences and similarities between the two conditions are reflected by their pathophysiology. Areas covered: An overview of immunological aspects, pharmacological management, and biomarkers of IBD is provided. The role of adsorptive granulocyte and monocyte apheresis (GMA) is reviewed including its primary and secondary effects on the immune system, as well as clinical studies in IBD (mainly UC), and potential biomarkers for adsorptive GMA. Expert opinion: In UC, adsorptive GMA with Adacolumn (Adacolumn®, JIMRO Co., Ltd. Takasaki, Gunma, Japan) selectively depletes elevated myeloid lineage leukocytes and has a range of beneficial secondary immune effects. Adsorptive GMA is a safe and effective non-pharmacological treatment option for UC. Pilot studies have reported promising results for adsorptive GMA in combination with biological agents, although larger studies are required. Fecal calprotectin concentrations, neutrophil counts in histological samples and/or the neutrophil/lymphocyte ratio in peripheral blood may prove to be useful biomarkers for predicting GMA effectiveness in the future.

https://pubmed.ncbi.nlm.nih.gov/35833363/

https://www.tandfonline.com/doi/epub/10.1080/17474124.2022.2100759?needAccess=true

UEG WEEK VIRTUAL 2021

GMA induces specific immunoregulatory changes in leukocyte’s subpopulations. We confirm the depletion of the
monocytes with proinflammatory phenotype after GMA. Treg and B effector cells shift to a more immunotolerant phenotype. The emergence of subpopulations with the atypical immunofluorescence staining (CXCR3+CRTH2+) related to immature T cells support the immunomodulatory effects of GMA. These findings could help to understand the pathology of UC and to identify targeted immune subpopulations for treatment

P0246 UEG.pdf

Nobuhiro Ueno, Yuya Sugiyama, Yu Kobayashi, Yuki Murakami et al DOI: https://doi.org/10.21203/rs.3.rs-154609/v1

In summary, we demonstrated the utility of FC as a biomarker for assessing ER after GMA and predicting CR at the early phase during GMA in patients with active UC. Assessing the baseline characteristics alone before GMA was not sufficient to predict CR. Our findings will benefit patients with active UC by allowing them to avoid undergoing unnecessary invasive procedures and will help establish new GMA therapeutic strategies.

https://www.researchsquare.com/article/rs-154609/v1

https://assets.researchsquare.com/files/rs-154609/v1/13c1025f-0cf0-4c37-8238-a76d8ff621a7.pdf

Nobuhito Kashiwagi , Fumio Saito , Hidetaka Maegawa , Kenta Kaneda, Cytokine 2021 Mar;139:155410.

Objective: Apoptotic cells participate in maintenance of homeostasis of the adaptive immune system. Granulocyte/monocyte adsorptive apheresis (GMA) performed with an Adacolumn has been shown to have clinical efficacy together with immunomodulatory effects for immune-mediated disorder cases, such as inflammatory bowel disease (IBD) or psoriatic arthritis. Although induction of apoptosis in neutrophils by GMA has been observed, the detailed mechanism remains unclear. Methods: To focus on phagocytosis-induced cell death (PICD) that induces apoptotic neutrophils, a comparative study utilizing a GMA-carrier (leukocyte adsorbing carrier for Adacolumn) and yeast particles was performed with in vitro and in vivo examinations. Results: L-selectin was significantly (P = 0.0133) shed, reactive oxygen species (ROS) production was promoted (P = 0.0019), and apoptosis induction was enhanced (P = 0.0087) by peripheral blood co-cultured with the GMA-carrier or yeast particles as compared to incubated blood alone. Furthermore, degranulation of myeloperoxidase, elastase, and lactoferrin was increased by both treatments, while the highest level of interleukin-1 receptor antagonist release was found with GMA-carrier treatment (P = 0.0087) as compared to the yeast particles. Plasma from blood treated with the GMA-carrier showed chemotactic activity, and suppressed neutrophil migration to IL-8 and LTB₄. In vivo results demonstrated that neutrophil chemotaxis to IL-8 was desensitized (P = 0.0078) in rabbits following GMA apheresis, while CXCR1 and CXCR2 expressions in neutrophils were reduced by exposing peripheral blood to the GMA-carrier. Conclusions: GMA may regulate the immune system in patients with an immune-mediated disorder by inducing a biological response of neutrophils with a PICD-like reaction.

https://pubmed.ncbi.nlm.nih.gov/33395614/

Szabolcs Kiss, Dávid Németh, Péter Hegyi , Mária Földi , Zsolt Szakács, Bálint Erőss , Benedek Tinusz , Péter Jenő Hegyi, Patrícia Sarlós , Hussain Alizadeh, BMJ Open 2021 May 19;11(5):e042374.

The results support the hypothesis that patients with active UC have a better chance of clinical remission if GMA is administered as an adjunctive therapy. As regards the frequency of AEs, we found no statistically significant difference between the two groups. With regard to remission maintenance, GMA was identified as an effective alternative therapeutic option

https://pubmed.ncbi.nlm.nih.gov/34011580/

e042374.full.pdf (bmj.com)