Neutrophil Migratory Patterns: Implications for Cardiovascular Disease

Conceptual Contextualization of Neutrophilic Dermatoses

ABSTRACT

Neutrophilic dermatoses are defined as inflammatory skin diseases characterized by sterile infiltration of polymorphonuclear neutrophils into various cutaneous layers. Although, in many cases, neutrophilic dermatoses represent the cutaneous counterpart of autoinflammatory diseases, this is not always the case, and there are other causes associated with this group of diseases, such as the administration of certain drugs or an underlying tumor. However, understanding the autoinflammatory context in which most of these entities develop, as well as their close relationship with autoimmunity, is key to comprehending their pathogenesis. In addition, understanding the mechanisms by which neutrophils migrate to the dermis and become activated is fundamental for interpreting the morphological findings of these biopsies. Finally, the description of a new group of neutrophilic dermatoses in recent years, in relation to keratinization disorders, has been crucial for understanding the best therapeutic approach for these difficult-to-manage entities.

Mononuclear cell recruitment during extracorporeal photopheresis: Partial results of a phase 1/2 randomized clinical trial in multiple sclerosis

BACKGROUND

Despite the routine clinical use of extracorporeal photopheresis (ECP) for the last decades, there has been no sufficient investigation on the intra-apheresis dynamics of mononuclear cells (MNCs).

OBJECTIVE

This research aims to verify the "intra-apheresis recruitment" (IAR) of MNCs, which may be particularly useful in cases with low preapheresis MNC counts.

METHODS

Prospective data of ECP procedures for patients with multiple sclerosis (MS) in the context of the PHOMS study (NCT05168384) were analyzed. ECPs were performed with the use of the Therakos® CellEx® Photopheresis System, and the recruitment factor (RF), collection efficiency 1 (CE1), and fold enrichment (FE) for MNCs, lymphocytes, monocytes, and neutrophils were calculated at various intervals per the approved protocol.

RESULTS

A total of 252 ECP procedures were performed on nine patients with MS, and data from 45 ECPs were analyzed for this study. IAR (RF ≥ 1) of MNCs, lymphocytes, and monocytes was observed in the 93.3 %, 95.5 %, and 88.8 % of the ECP procedures, respectively. CE1 exceeded 100 % for these populations in 13.3 %, 11.1 %, and 24.4 % of ECPs, while FE ≥ 1 for MNCs and lymphocytes was found in all ECPs, and in 97.8 % of ECPs for monocytes. Additionally, RF correlated positively with CE1 for MNCs (r = 0.40, p = 0.006) and lymphocytes (r = 0.43, p = 0.003), as well as with FE for monocytes (r = 0.39, p = 0.01) and lymphocytes (r = 0.48, p = 0.001), further improving collection quality.

CONCLUSIONS

Administering photopheresis with suboptimal MNC counts was plausible and did not worsen the anticipated cytopenias. Moreover, our findings revealed sustained IAR of MNCs in patients with MS who underwent ECP.

The action of injectable nanodispersion of Bixa orellana (Chronic-in®) on arthritis in diabetic rats: pharmacological and histopathological studies

Diabetic arthritis (DA) is a microvascular complication associated with diabetes mellitus (DM), necessitating the exploration of innovative therapeutic approaches. The Amazon biome, rich in bioactive compounds, offers potential treatments; notably, Bixa orellana, which contains tocotrienol and geranylgeraniol, exhibits anti-inflammatory and antioxidant properties, particularly when formulated as a nanodispersion.

OBJECTIVE

This study aims to investigate the pharmacological effects of an injectable nanodispersion of Bixa orellana, termed Chronic-in®, in diabetic Wistar rats.

METHOD

Male Wistar rats were employed in the study, and DA was induced using an intraperitoneal injection of 100 mg/kg alloxan and an intraplantar administration of Freund's complete adjuvant. The animals were divided into five groups (n = 5): CON (normal rats treated with saline solution IM), CHR SC (DA rats treated with Chronic-in SC daily), SS (DA rats treated with saline solution IM), IND (DA rats treated with indomethacin orally), and CHR IM (DA rats treated with Chronic-in IM every 3 days). Treatment outcomes were assessed through various parameters, including changes in paw edema, Arthritic Index (AI), performance in the open field and Rotarod tests, radiographic evaluations using the Eichenholtz classification, Scanning Electron Microscopy (SEM) analysis of articular morphology, and hematological and biochemical assessments.

RESULTS

Significant reductions in edema were observed in the CHR SC, CHR IM, and IND groups (p < 0.001) compared to the SSA group. The AI showed significant differences among the CON, CHR SC, and CHR IM groups. Enhanced exploratory behavior was noted in the open field test for the Chronic-in-treated groups, particularly with IM administration. The Rotarod test demonstrated marked differences between the Chronic-in-treated, CON and SS groups. Radiographic and SEM evaluations indicated fewer bone alterations in the CHR IM and SC groups compared to the SSA and IND groups, along with preservation of articular surfaces. Histological assessments revealed thickened synovial membranes and pannus formation in the SS and IND groups. In contrast, CHR IM and CHR SC groups exhibited minimal loss of proteoglycans akin to the CON group.

CONCLUSION

Treatment with Chronic-in via both IM and SC routes effectively mitigated the inflammatory manifestations of diabetic neuropathic arthritis, demonstrating lower pain intensity during ambulation and protective effects against inflammation and joint integrity as evidenced in histological analyses. These findings suggest that Chronic-in represents a promising therapeutic option for diabetic arthritis.

The Impact of Neutrophil-to-High-Density Lipoprotein Ratio and Serum 25-Hydroxyvitamin D on Ischemic Heart Disease

Background: This study describes the complex association between the neutrophil-to-high-density lipoprotein cholesterol ratio (NHR), 25-hydroxyvitamin D (25(OH)D) levels, and cardiovascular disease (CVD), such as stable ischemic heart disease (IHD), ST elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA). Methods: The serum 25(OH)D concentration and NHR values were analyzed in groups of patients with chronic coronary syndrome (CCS) and acute coronary syndrome (ACS). The severity of coronary artery atherosclerosis was determined using the Coronary Artery Surgery Study (CASS) scale. Results: Significant differences in 25(OH)D and NHR concentrations were observed between CCS and (ACS)/STEMI patients (p < 0.01). Higher 25(OH)D concentrations were associated with the diagnosis of CCS, and higher NHR values with the diagnosis of ACS/STEMI. The NHR threshold for ACS was set at 0.10 (p < 0.001). Patients without significant coronary artery stenosis showed significantly higher 25(OH)D levels and lower NHR values (p < 0.01). Conclusions: The significant correlation between 25(OH)D, HDL, and the NHR suggests that vitamin D, through its influence on inflammatory processes and lipid metabolism, may play a role in the pathogenesis of chronic and acute coronary syndromes. The suggested bidirectional relationship between the NHR and 25(OH)D and the role of the NHR as a predictor of vitamin D levels require further well-designed studies.

Adrenergic orchestration of immune cell dynamics in response to cardiac stress

Immune cells contribute approximately 5-10 % of the heart's total cell population, including several myeloid cell and lymphocyte cell subsets, which, despite their relatively small percentages, play important roles in cardiac homeostasis and remodeling responses to various forms of injury and long-term stress. Pathological cardiac stress activates the sympathetic nervous system (SNS), resulting in the release of the catecholamines epinephrine and norepinephrine either systemically or from sympathetic nerve terminals within various lymphoid organs. Acting at α- or β-adrenergic receptors (αAR, βAR), catecholamines regulate immune cell hematopoiesis, egress and migration in response to stress. Classically, αAR stimulation tends to promote inflammatory responses while βAR stimulation has typically been shown to be immunosuppressive, though the effects can be nuanced depending on the immune cells subtype, the site of regulation and pathophysiological context. Herein, we will discuss several facets of SNS-mediated regulation of immune cells and their response to cardiac stress, including: catecholamine response to cardiovascular stress and action at their receptors, adrenergic regulation of hematopoiesis, immune cell retention and release from the bone marrow, adrenergic regulation of splenic immune cells and their retention, as well as adrenergic regulation of immune cell recruitment to the injured heart, including neutrophils, monocytes and macrophages. A particular focus will be given to βAR-mediated effects on myeloid cells in response to acute or chronic cardiac stress.

Immune and inflammatory mechanisms of abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is a life-threatening cardiovascular disease. Immune-mediated infiltration and a destruction of the aortic wall during AAA development plays significant role in the pathogenesis of this disease. While various immune cells had been found in AAA, the mechanisms of their activation and function are still far from being understood. A better understanding of mechanisms regulating the development of aberrant immune cell activation in AAA is essential for the development of novel preventive and therapeutic approaches. In this review we summarize current knowledge about the role of immune cells in AAA and discuss how pathogenic immune cell activation is regulated in this disease.

Insights into the Role of Neutrophils and Neutrophil Extracellular Traps in Causing Cardiovascular Complications in Patients with COVID-19: A Systematic Review

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 virus has resulted in significant mortality and burdening of healthcare resources. While initially noted as a pulmonary pathology, subsequent studies later identified cardiovascular involvement with high mortalities reported in specific cohorts of patients. While cardiovascular comorbidities were identified early on, the exact manifestation and etiopathology of the infection remained elusive. This systematic review aims to investigate the role of inflammatory pathways, highlighting several culprits including neutrophil extracellular traps (NETs) which have since been extensively investigated.

METHOD

A search was conducted using three databases (MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations and EMBASE). Data from randomized controlled trials (RCT), prospective series, meta-analyses, and unmatched observational studies were considered for the processing of the algorithm and treatment of inflammatory response during SARS-CoV-2 infection. Studies without the SARS-CoV-2 Infection period and case reports were excluded.

RESULTS

A total of 47 studies were included in this study. The role of the acute inflammatory response in the propagation of the systemic inflammatory sequelae of the disease plays a major part in determining outcomes. Some of the mechanisms of activation of these pathways have been highlighted in previous studies and are highlighted.

CONCLUSION

NETs play a pivotal role in the pathogenesis of the inflammatory response. Despite moving into the endemic phase of the disease in most countries, COVID-19 remains an entity that has not been fully understood with long-term effects remaining uncertain and requiring ongoing monitoring and research.

Immune cell dynamics in response to an acute laboratory stressor: a within-person between-group analysis of the biological impact of early life adversity

Early life adversity (ELA) is a risk factor for early onset morbidities and mortality, a relationship that may be driven in part by immune system dysregulation. One mechanism of dysregulation that has yet to be fully examined in the context of ELA is alterations to immune cell dynamics in response to acute stress. Using a within-person between-group experimental design, we investigated stress-induced changes in immune cell populations, and how these changes may be altered in individuals with a history of ELA. Participants were young adults (N = 34, aged 18-25 years, 53% female, 47% with a history of ELA). Complete immune cell counts were measured at four time-points over a 5-hour window across two sessions (Trier Social Stress Test [TSST] vs. no-stress) separated by a week. Across all participants, total white blood cells increased over time (F(3,84)=38.97, p < .001) with a greater increase in response to the TSST compared to the no-stress condition at 240 minutes post-test (b = 0.43±.19; t(179)=2.22, p = .027). This pattern was mirrored by neutrophil counts. Lymphocyte counts were initially depressed by TSST exposure (b =-205±.67; t(184)=-3.07, p = .002) but recovered above baseline. ELA status was associated with higher stress-induced immune cell counts, a difference likely driven by increases in neutrophils (F(1,22)=4.45, p = .046). Overall, these results indicate differential immune cell dynamics in response to acute stress in individuals with a history of ELA. This points to altered immune system functioning in the context of stress, a finding that may be driving increased morbidity and mortality risk for ELA-exposed individuals.