Yuko Higashi ^1 2, Atsuko Ibusuki ¹, Tomoko Fukushige ¹, Ryoko Sagara ¹, Risako Yonezawa ¹, Natsumi Terada ¹, Hisao Kawahira ¹, Kimiko Kazumura ³, Takuro Kanekura ¹

Ther Apher Dial. 2025 Aug;29(4):702-706. doi: 10.1111/1744-9987.70043. Epub 2025 May 25.

Introduction: Activated neutrophils play a crucial role in the development of neutrophilic dermatoses, including pustular psoriasis. Adsorptive granulocyte and monocyte apheresis (GMA) is an effective treatment for skin disorders. Although previous basic research has demonstrated neutrophil activation, no efficient method exists to assess it in clinical settings.

Methods: We measured neutrophil activity in patients with GPP who underwent GMA therapy using the FLP-H4200, a newly developed neutrophil activity evaluation system. Blood samples were collected before the first and after the fifth GMA session.

Results: In Case 1, which responded to GMA, the neutrophil activation value decreased from 118 603 to 26 234, reaching the normal range. In Case 2, the response to GMA was poor, and the neutrophil activation value decreased from 140 623 to 76 780, which remained significantly above the normal level.

Conclusion: These results suggest that the neutrophil activity evaluation system may be useful for assessing disease severity and therapeutic efficacy.

Ludovica Franceschin ¹, Alessia Guidotti ¹, Roberto Mazzetto ¹, Jacopo Tartaglia ¹, Christian Ciolfi ¹, Mauro Alaibac ¹, Alvise Sernicola ¹

Biomolecules. 2024 Nov 27;14(12):1515. doi: 10.3390/biom14121515.

Neutrophil-mediated inflammation is a key feature of immune-mediated chronic skin disorders, but the mechanistic understanding of neutrophil involvement in these conditions remains incomplete. Dapsone, colchicine, and tetracyclines are established drugs within the dermatologist’s therapeutic armamentarium that are credited with potent anti-neutrophilic effects. Anti-neutrophilic drugs have established themselves as versatile agents in the treatment of a wide range of dermatological conditions. Some of these agents are approved for the management of specific dermatologic conditions, but most of their current uses are off-label and only supported by isolated reports or case series. Their anti-inflammatory and immunomodulatory properties make them particularly valuable in managing auto-immune bullous diseases, neutrophilic dermatoses, eosinophilic dermatoses, interface dermatitis, and granulomatous diseases that are the focus of this review. By inhibiting inflammatory pathways, reducing cytokine production, and modulating immune responses, they contribute significantly to the treatment and management of these complex skin conditions. Their use continues to evolve as our understanding of these diseases deepens, and they remain a cornerstone of dermatological therapy.

GMA is a promising alternative in patients who have failed conventional therapies for generalized pustular psoriasis, pyoderma gangrenosum, Behçet’s disease, and hidradenitis suppurativa. The strengths of GMA lie in its favorable tolerability and peculiar mode of action that is able to deplete inflammation without causing immunodeficiency.

Tomoyuki Nakamura, Kazuhiro Moriyama, Toshikazu Sakai, Yu Kato & Osamu Nishida 

Ren Replace Ther 10, 51 (2024). https://doi.org/10.1186/s41100-024-00565-9

Background

Sepsis 3 definitions have shifted the focus from nonspecific inflammation to sepsis as an organ dysfunction caused by a dysregulated host response to infection. Neutrophils have become therapeutic targets because of their intimate but complex involvement in sepsis. We conducted ex vivo and animal experiments to apply a granulocyte and monocyte adsorption column, which is clinically used for inflammatory bowel disease, in sepsis. In this study, the biocompatibility was evaluated in sepsis-like hypercytokinemia.

Methods

Six female outbred pigs were anesthetized. Extracorporeal direct hemoperfusion (DHP) with an Adacolumn or a sham column was initiated after lipopolysaccharide (LPS) administration. The DHP was performed for 2 h at a blood flow rate (QB) of 30 or 60 mL/min. Blood samples were collected before and during the DHP (30, 60, 90, and 120 min). The percentage change in white blood cell count, platelet count, and cytokine concentration was compared between the Adacolumn and sham columns.

Results

The percentage change in white blood cells were 96 (95–98)% and 106 (101–108)% in the Adacolumn and sham groups, respectively, at QB = 60 mL/min (p < 0.01). The percentage change in platelets were 95 (90–96)% and 97 (93–99)% in the in the Adacolumn and sham groups, respectively, at QB = 60 mL/min (not significant; n.s.). At QB = 60 mL/min, the percentage change in tumor necrosis factor-α, interleukin (IL)-6, and IL-10 were 92 (81–106)%, 95 (93–102)%, and 98 (95–100)%, respectively, for the Adacolumn and 100 (95–102)%, 98 (87–104)%, and 97 (93–99)%, respectively, for the sham column. The percentage change in white blood cell counts, platelet counts, and all cytokines at QB = 30 and 60 mL/min showed similar trends.

Conclusion

The biocompatibility of the Adacolumn was evaluated using a porcine LPS-induced inflammation model. No decrease in platelet counts or significant cytokine production was observed, suggesting that the Adacolumn could be safely used in patients with sepsis with QB = 30–60 mL/min for 2 h. However, production of mediators other than cytokines remains unknown and requires further investigation.

Teagan S Edwards ¹, Andrew S Day ¹

Expert Rev Mol Diagn.. 2024 Jun;24(6):497-508. doi: 10.1080/14737159.2024.2375224. Epub 2024 Jul 12.

Introduction: Inflammatory bowel disease (IBD), encompassing Crohn’s disease (CD) and Ulcerative Colitis (UC), is a relapsing and remitting condition. Noninvasive biomarkers have an increasingly important role in the diagnosis of IBD and in the prediction of future disease course in individuals with IBD. Strategies for the management of IBD increasingly rely upon close monitoring of gastrointestinal inflammation.

Areas covered: This review provides an update on the current understanding of established and novel stool-based biomarkers in the diagnosis and management of IBD. It also highlights key gaps, identifies limitations, and advantages of current markers, and examines aspects that require further study and analysis.

Expert opinion: Current noninvasive inflammatory markers play an important role in the diagnosis and management of IBD; however, limitations exist. Future work is required to further characterize and validate current and novel markers of inflammation. In addition, it is essential to better understand the roles and characteristics of noninvasive markers to enable the appropriate selection to accurately determine the condition of the intestinal mucosa.

• Noninvasive inflammatory markers play an important role in diagnosis and management of IBD.
• Fecal inflammatory markers can reflect gut inflammation in IBD; however, they are not specific and various limitations must be considered.
• Although FCal is the most well-established and routinely used marker in IBD, it may have reduced sensitivity and specificity in some settings.
• Several emerging biomarkers including MPO have been assessed and show promise.
• Identification of effective and accurate noninvasive markers of inflammation may limit the need for repeat invasive endoscopic examinations in the future.

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.

Tomotaka Tanaka

Cureus 2023 Nov 16;15(11):e48913. doi: 10.7759/cureus.48913. eCollection 2023 Nov.

The major phenotypes of inflammatory bowel disease (IBD) include ulcerative colitis (UC) and Crohn’s disease (CD), which cause debilitating symptoms, including bloody diarrhea, abdominal discomfort, and fever. Patients require life-long immunosuppressive medications, which cause adverse side effects as additional morbidity factors. However, IBD is initiated and perpetuated by inflammatory cytokines, and given that in patients with IBD myeloid lineage leukocytes are elevated with activation behavior and release inflammatory cytokines, selective depletion of elevated granulocytes and monocytes by granulomonocytapheresis is a relevant therapeutic option for IBD patients. Therefore, a column filled with specially designed beads as granulomonocytapheresis carriers for selective adsorption of myeloid lineage leukocytes (Adacolumn) has been applied to treat patients with active IBD. Patients receive up to 10 granulomonocytapheresis sessions at one or two sessions per week. During each session, the carriers adsorb up to 60% of the myeloid leukocytes from the blood that passes through the granulomonocytapheresis column. Efficacy rates in the UC setting have been as high as 85% in steroid-naïve patients, and 100% in drug-naïve, first-episode cases, but patients with a long duration of active IBD and extensive colonic lesions that have become refractory to pharmacological treatment have not responded well. However, granulomonocytapheresis has a favorable safety profile. Given that immunosuppressive medications used to treat IBD potentially may increase the risk of severe viral infection, non-drug granulomonocytapheresis should be a favorable treatment strategy. Further, by targeting granulomonocytapheresis to patients with background features and identifying a patient as a likely responder, futile use of medical resources is avoided.

Therapeutic Granulomonocytapheresis as a Non-pharmacologic Treatment Option for Inflammatory Bowel Disease: Efficacy Reports on a Wide Age Range and Disease Profile – PubMed (nih.gov)

Therapeutic Granulomonocytapheresis as a Non-pharmacologic Treatment Option for Inflammatory Bowel Disease: Efficacy Reports on a Wide Age Range and Disease Profile – PMC (nih.gov)

Muhammad Hassan Shakir 1 2, Salman A Basit 1, Syed Muhammad Hussain Zaidi 1, Sarasija Natarajan 1, Omar Z Syed 1, Mohammad Asim Amjad 1, Douglas Klamp, Cureus. 2023 Nov 6;15(11):e48399. doi: 10.7759/cureus.48399. eCollection 2023

Sweet syndrome (SS) is an acute febrile neutrophilic dermatosis. Although perceived to be rare, the disease may well have been underreported due to lack of exposure in low-volume clinical settings and due to the use of rather strict clinical criteria for diagnosis. It presents as cutaneous papules, plaques, or nodules in an asymmetric distribution that follows fever and flu-like symptoms. Data on the disease is ever-expanding. Several associations have been identified, including drugs, infections, malignancies, and autoimmune diseases. Different disease patterns and histological variants have been identified. Pathophysiology is complex and multifactorial but appears to involve mechanisms that negatively influence neutrophil apoptosis and facilitate neutrophil recruitment. The existing diagnostic criteria exclude cases with vasculitis; over time, cases of neutrophilic dermatoses with vasculitis have been reported as SS as long as other criteria were met. Newer diagnostic models have been proposed, some arguing against the exclusion of vasculitis. Steroids continue to be the mainstay of treatment, and steroid responsiveness continues to be a part of the diagnostic criteria, although newer treatment modalities have been used and have shown promise. No established guidelines exist for management. We present a case of Idiopathic SS with vasculitis along with a brief review of the existing literature. We agree to the inclusion of vasculitis as proposed by the newer diagnostic criteria.

Grisell Starita-Fajardo 1, David Lucena-López 1, María Asunción Ballester-Martínez 2, Montserrat Fernández-Guarino 2, Andrés González-García Int J Mol Sci. 2023 Oct 26;24(21):15622. doi: 10.3390/ijms242115622

Neutrophilic dermatoses (NDs) are a group of noninfectious disorders characterized by the presence of a sterile neutrophilic infiltrate without vasculitis histopathology. Their physiopathology is not fully understood. The association between neutrophilic dermatoses and autoinflammatory diseases has led some authors to propose that both are part of the same spectrum of diseases. The classification of NDs depends on clinical and histopathological features. This review focuses on the recent developments of treatments in these pathologies.

Arun K. Mankan, Paulina Czajka-Francuz, Maria Prendes, Sriram Ramanan, Marcin Koziej, Laura Vidal, Kamal S. Saini Front. Immunol., 2023, 14, doi.org=10.3389/fimmu.2023.1208137

As the first responders, neutrophils lead the innate immune response to infectious pathogens and inflammation inducing agents. The well-established pathogen neutralizing strategies employed by neutrophils are phagocytosis, the action of microbicide granules, the production of ROS, and the secretion of neutrophil extracellular traps (NETs). Only recently, the ability of neutrophils to sense and respond to pathogen-associated molecular patterns is being appreciated. This review brings together the current information about the intracellular recognition of DNA by neutrophils and proposes models of signal amplification in immune response. Finally, the clinical relevance of DNA sensing by neutrophils in infectious and non-infectious diseases including malignancy are also discussed.