The Relevance of Anti-PF4 Antibody Isotypes and Endogenous Glycosaminoglycans and their Relationship with Inflammatory Biomarkers in Pulmonary Embolism Patients

Glycemic Control and Plasma Levels of Pro-Inflammatory and Pro-Thrombotic Biomarkers in Diabetic Patients Presenting with Acute Pulmonary Embolism

Type I and type II diabetes are closely associated with a pro-inflammatory state and to a pro-thrombotic state. The role of glycemic control in pulmonary embolism (PE) is poorly understood and requires additional investigation. The aim of this study is to investigate the relationship between glycemic control and thrombo-inflammatory biomarkers in a PE patient cohort compared to normal samples. Demographic and clinical information for 86 diabetic patients and 106 non-diabetic patients presenting with acute PE was collected via retrospective chart review. Plasma levels of pro-inflammatory (C-reactive protein [CRP], tumor necrosis factor-alpha [TNF-α], interleukin-6 [IL-6]) and pro-thrombotic (d-dimer, plasminogen activator inhibitor-1 [PAI-1], tissue plasminogen activator [tPA], thrombin activatable fibrinolysis inhibitor [TAFI], von-Willebrand factor [vWF], endogenous glycosaminoglycans [GAGs]) biomarkers were drawn within 24 hours of diagnosis of acute PE. Data was also obtained for a population of healthy adult controls. All the pro-inflammatory and pro-thrombotic biomarkers were elevated in diabetic PE patients in comparison to healthy controls. None of the biomarkers were elevated in diabetic PE patients when compared to non-diabetic PE patients. There was no difference in the levels of the pro-inflammatory biomarkers according to glycemic control. The plasma level of TAFI was elevated in diabetic patients with poor glycemic control. Diabetic patients were more likely to have a more severe PE. These studies demonstrate that thrombo-inflammatory biomarkers are elevated in diabetic PE patients with associated comorbidities in comparison to normal individuals. However, there is no difference between the PE cohort alone in comparison to PE with diabetes. The role of TAFI within the continuum of diabetic vascular disease warrants additional investigation.

Endogenous Glycosaminoglycans in Various Pathologic Plasma Samples as Measured by a Fluorescent Quenching Method

Endogenous glycosaminoglycans (GAGs) with a similar structure to heparin are widely distributed in various tissues. A fluorescence probe, namely Heparin Red, can detect polyanionic GAGs in plasma samples. The purpose of this study is to measure endogenous GAGs in various plasma samples obtained from different pathologic states in comparison to healthy controls utilizing this method. Plasma samples were obtained from patient groups including atrial fibrillation (AF), end-stage-renal-disease (ESRD), diabetes mellitus (DM), sepsis, cancer, liver disease (LD), and pulmonary embolism (PE). Normal human plasma (NHP) was used as healthy controls. The Heparin Red kit from Red Probes (Münster, Germany) was used for the quantification of endogenous GAGs in each sample before and after heparinase I degradation. All results were compiled as group means  ±  SD for comparison. NHP was found to have relatively low levels of endogenous GAGs with a mean concentration of 0.06 μg/mL. The AF, ESRD, DM, and sepsis patient samples had a mean endogenous GAG concentration of 0.55, 0.72, 0.92, and 0.94 μg/mL, respectively. The levels of endogenous GAGs were highest in cancer, LD, and PE patient plasma samples with a mean concentration of 1.95, 2.78, and 2.83 μg/mL, respectively. Heparinase I degradation resulted in a decline in GAG levels in plasma samples. These results clearly show that detectable Heparin Red sensitive endogenous GAGs are present in circulating plasma at varying levels in various patient groups. Additional studies are necessary to understand this complex pathophysiology.

The Chemokines CXC, CC and C in the Pathogenesis of COVID-19 Disease and as Surrogates of Vaccine-Induced Innate and Adaptive Protective Responses

COVID-19 is one of the progressive viral pandemics that originated from East Asia. COVID-19 or SARS-CoV-2 has been shown to be associated with a chain of physio-pathological mechanisms that are basically immunological in nature. In addition, chemokines have been proposed as a subgroup of chemotactic cytokines with different activities ranging from leukocyte recruitment to injury sites, irritation, and inflammation to angiostasis and angiogenesis. Therefore, researchers have categorized the chemotactic elements into four classes, including CX3C, CXC, CC, and C, based on the location of the cysteine motifs in their structures. Considering the severe cases of COVID-19, the hyperproduction of particular chemokines occurring in lung tissue as well as pro-inflammatory cytokines significantly worsen the disease prognosis. According to the studies conducted in the field documenting the changing expression of CXC and CC chemokines in COVID-19 cases, the CC and CXC chemokines contribute to this pandemic, and their impact could reflect the development of reasonable strategies for COVID-19 management. The CC and the CXC families of chemokines are important in host immunity to viral infections and along with other biomarkers can serve as the surrogates of vaccine-induced innate and adaptive protective responses, facilitating the improvement of vaccine efficacy. Furthermore, the immunogenicity elicited by the chemokine response to adenovirus vector vaccines may constitute the basis of vaccine-induced immune thrombotic thrombocytopaenia.