Genetic variants in platelet factor 4 modulate inflammatory and platelet activation biomarkers

Association of systemic immune-inflammation index with malnutrition among Chinese hospitalized patients: a nationwide, multicenter, cross-sectional study

Background

Systemic immune-inflammation index (SII) is associated with increased risk in a wide range of illnesses. However, few studies have explored the associations between SII and the risk of malnutrition. Therefore, this study aimed to investigate the association between SII and malnutrition in a nationwide, multicenter, cross-sectional study involving Chinese hospitalized patients.

Design

From August 2020 to August 2021, a total of 40,379 hospitalized patients met the inclusion and exclusion criteria. Detailed demographic data, diagnoses, as well as physical and laboratory examination results were recorded. The diagnosis of malnutrition was used with two distinct methods: the Malnutrition Screening Tool 2002 (NRS 2002) + Global Leaders Initiative on Malnutrition (GLIM) criteria and the controlling nutritional status (CONUT) score. The risk factors for malnutrition were analyzed using binary logistic regression and multiple logistic regression to obtain odds ratios (OR) and 95% confidence intervals (CI). Restricted cubic spline (RCS), linear spline, and receiver operating characteristic (ROC) analysis were also used.

Results

The prevalence of malnutrition diagnosed by the two methods was 13.4% and 14.9%, respectively. In the NRS 2002 + GLIM diagnostic model, lnSII showed statistical significance between the malnutrition and non-malnutrition group (6.28 ± 0.78 vs. 6.63 ± 0.97, p < 0.001). A positive association was observed between higher SII and the risk of malnutrition in both before and after adjustment models compared to the first quartile (Q3 vs. Q1, OR = 1.27, 95%CI: 1.15-1.40; Q4 vs. Q1, OR = 1.83, 95%CI: 1.67-2.00). However, a significant reduction in prevalence was observed when SII was in the second quartile (Q2 vs. Q1, OR < 1), as indicated by a restricted cubic spline with a U trend (p for nonlinear <0.001). According to the CONUT score, the prevalence of individuals with normal nutritional status decreased with increasing SII, while the occurrence of three different degrees of malnutrition generally increased. The Kappa value between the two diagnostic methods was 0.23, and the merged data observed an area under the ROC curve of 0.73 (95%CI: 0.714-0.742).

Conclusion

The U-shaped association between SII and the prevalence of malnutrition was observed. Both lower and higher SII levels (either continuous or categorical variable) were significantly associated with an increased risk of malnutrition.

Inflammatory Mediators of Platelet Activation: Focus on Atherosclerosis and COVID-19

BACKGROUND

Atherosclerotic cardiovascular diseases are characterized by a dysregulated inflammatory and thrombotic state, leading to devastating complications with increased morbidity and mortality rates.

SUMMARY

In this review article, we present the available evidence regarding the impact of inflammation on platelet activation in atherosclerosis. Key messages: In the context of a dysfunctional vascular endothelium, structural alterations by means of endothelial glycocalyx thinning or functional modifications through impaired NO bioavailability and increased levels of von Willebrand factor result in platelet activation. Moreover, neutrophil-derived mediators, as well as neutrophil extracellular traps formation, have been implicated in the process of platelet activation and platelet-leukocyte aggregation. The role of pro-inflammatory cytokines is also critical since their receptors are also situated in platelets while TNF-α has also been found to induce inflammatory, metabolic, and bone marrow changes. Additionally, important progress has been made towards novel concepts of the interaction between inflammation and platelet activation, such as the toll-like receptors, myeloperoxidase, and platelet factor-4. The accumulating evidence is especially important in the era of the coronavirus disease-19 pandemic, characterized by an excessive inflammatory burden leading to thrombotic complications, partially mediated by platelet activation. Lastly, recent advances in anti-inflammatory therapies point towards an anti-thrombotic effect secondary to diminished platelet activation.

Functional Molecular Network Analysis Enables Prediction of Response to Vedolizumab Therapy in Anti-TNF Refractory IBD Patients

BACKGROUND

We applied for the first time 2 label-free technologies, physiological intermolecular modulation spectroscopy (PIMS) and nematic protein organization technic (NPOT) in anti-tumor necrosis factor (TNF) refractory inflammatory bowel disease (IBD) patients to identify clinical responders to vedolizumab therapy and elucidate their underlying functional molecular network.

METHODS

PIMS analysis was performed in peripheral blood taken prior to the first vedolizumab application in 20 IBD patients (Crohn disease n = 13; ulcerative colitis n = 7) refractory to at least 1 previous anti-TNF agent therapy. Peripheral blood taken from clinical responders and nonresponders at week 14 of vedolizumab therapy were additionally subjected to NPOT analysis. Response to therapy was assessed by respective clinical disease activity scores (partial Mayo Score and Harvey-Bradshaw Index).

RESULTS

Clinical response to vedolizumab treatment was observed in 7 of 13 Crohn disease and 4 of 7 ulcerative colitis patients at week 14. Response to therapy was accurately predicted by PIMS blood analysis in 100% of ulcerative colitis and 77% of Crohn disease patients. Overall prediction of clinical response with PIMS blood analysis was achieved with a 89% positive predictive value and a 82% negative predictive value. NPOT analysis revealed the heightened expression of the proteins ITGB7, ITGAV, ITG3, PF4, and ASGH in the peripheral blood of vedolizumab responders compared to nonresponders.

CONCLUSIONS

PIMS analysis of the blood of anti-TNF refractory IBD patients was able to stratify responders to vedolizumab therapy with high accuracy and specificity. NPOT technology could decipher underling molecular networks in the blood of responders, enabling subsequent personalized therapeutic approaches in IBD.

Analysis of genetic and clinical risk factors of post-transplant thrombocytopenia in kidney allograft recipients

BACKGROUND

Hematological abnormalities after transplantation are complications that may arise after renal transplantation, of which thrombocytopenia is associated with increased risk of bleeding and other complications. The development of thrombocytopenia is affected by various clinical conditions, and the stromal-derived factor 1 (SDF1) and platelet factor 4 (PF4) genes are known to be involved in the production or destruction of platelets. The purpose of this study was to investigate the prevalence of posttransplant thrombocytopenia and its association with other clinical conditions and genetic polymorphisms of SDF1 and PF4 genes a long time after transplantation.

METHODS

This is a retrospective study that includes a total of 305 kidney transplant (KT) recipients between 2008 and 2012 at St. Vincent Medical Center, Los Angeles, CA. In this study, posttransplant thrombocytopenia was defined as a 30% reduction in platelet count from the baseline in the first week or a decrease of <100 (×10³/μL) within 1 year after KT. The subjects were divided into posttransplant thrombocytopenia and control groups. The chi-square test, t-test, and logistic regression were used for the analyses.

RESULTS

In the first week, 65 patients had a 30% reduction in platelet count (21.3%). Gender, simultaneous kidney-pancreas transplantation, induction therapy (IT), and only alleles of rs2297630 of SDF1, among the SDF1 and PF4 genes, showed statistically significant differences. The rs2297630 alleles were consistently significant risk factors (non G vs. G: odds ratio = 0.445; 95% confidence interval, 0.224-0.884; p = .021) in the multiple logistic regression. In the 1-year study, 61 patients (20.0%) had platelet counts of <100 × 10³/μL and had statistically significant differences in patients who had delayed graft function and induction therapy.

CONCLUSIONS

In this study, non-G group of rs2297630 in SDF1 significantly increased the risk of post-transplant thrombocytopenia in the first week of kidney transplantation.

Serum Proteomics in African American Female Patients With Irritable Bowel Syndrome: An Exploratory Study

Background

Sex and subtype differences within patients with irritable bowel syndrome (IBS) complicate the understanding of disorder pathogenesis and hinder the design of efficacious, therapeutic interventions.

Objectives

The aims of this study were to harness the power of shotgun proteomic analysis, identify circulating proteins that differentiate African American female patients with IBS from healthy controls (HC), and gain biological insight on symptomatology.

Methods

Serum proteome analysis was performed upon a cohort of overweight, African American female participants with constipation predominant IBS symptoms (n = 5) and HC (n = 5), matched on age, sex, years of education, body mass index, and 11 physiological markers. Tandem mass tags for multiplexed proteomic analysis were performed, incorporating reverse-phase liquid chromatography and liquid chromatography-tandem mass spectrometry.

Results

Participants with IBS did not differ from HC in demographics, clinical characteristics, or initial proteomic analysis. Nested case control analysis of six samples (IBS: n = 3, HC: n = 3), hierarchically clustered into two main groups, with 12 out of 1,317 proteins significantly different in levels of expression: TGFβ1, PF4V1, PF4, APP, MMP9, PPBP, CTGF, SRGN, THBS1, WRN, LTBP1 (Isoform 3), and IGLV5-48. Top associations of identified proteins in DAVID and STRING resources (upregulated in HC vs. IBS) involve platelet alpha granule lumen, platelet activation/degranulation, extracellular region, and secretion by cell.

Discussion

Differentially expressed proteins between participants with IBS and HC involving platelet-related associations prompt inquiry as to differences in serotonergic signaling, inflammatory or immunomodulatory mechanisms underlying IBS symptomatology. Although preliminary and requiring validation in larger cohorts, these findings bear relevance to understanding pathogenic processes of IBS and biological effects of the disorder.

Integrative analysis for identification of shared markers from various functional cells/tissues for rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease. So far, it is unclear whether there exist common RA-related genes shared in different tissues/cells. In this study, we conducted an integrative analysis on multiple datasets to identify potential shared genes that are significant in multiple tissues/cells for RA. Seven microarray gene expression datasets representing various RA-related tissues/cells were downloaded from the Gene Expression Omnibus (GEO). Statistical analyses, testing both marginal and joint effects, were conducted to identify significant genes shared in various samples. Followed-up analyses were conducted on functional annotation clustering analysis, protein-protein interaction (PPI) analysis, gene-based association analysis, and ELISA validation analysis in in-house samples. We identified 18 shared significant genes, which were mainly involved in the immune response and chemokine signaling pathway. Among the 18 genes, eight genes (PPBP, PF4, HLA-F, S100A8, RNASEH2A, P2RY6, JAG2, and PCBP1) interact with known RA genes. Two genes (HLA-F and PCBP1) are significant in gene-based association analysis (P = 1.03E-31, P = 1.30E-2, respectively). Additionally, PCBP1 also showed differential protein expression levels in in-house case-control plasma samples (P = 2.60E-2). This study represented the first effort to identify shared RA markers from different functional cells or tissues. The results suggested that one of the shared genes, i.e., PCBP1, is a promising biomarker for RA.

Haemostaseome-associated SNPs: has the thrombotic phenotype a greater influence than ethnicity? GMT study from Aquitaine including Basque individuals

The Genetic Markers for Thrombosis (GMT) study compared the relative influence of ethnicity and thrombotic phenotype regarding the distribution of SNPs implicated in haemostasis pathophysiology ("haemostaseome"). We assessed 384 SNPs in three groups, each of 480 subjects: 1) general population of Aquitaine region (Southwestern France) used as control; 2) patients with venous thromboembolism from the same area; and 3) autochthonous Basques, a genetic isolate, who demonstrate unusual characteristics regarding the coagulation system. This study sought to evaluate i) the value of looking for a large number of genes in order to identify new genetic markers of thrombosis, ii) the value of investigating low risk factors and potential preferential associations, iii) the impact of ethnicity on the characterisation of markers for thrombosis. We did not detect any previously unrecognised SNP significantly associated with thrombosis risk or any preferential associations of low-risk factors in patients with thrombosis. The sum of ϰ² values for our 110 significant SNPs demonstrated a smaller genetic distance between patients and controls (321 cumulated ϰ² value) than between Basques and controls (1,570 cumulated ϰ² value). Hence, our study confirms the genetic particularity of Basques especially regarding a significantly lower expression of the non-O blood group (p< 0.0004). This is mitigated by a higher prevalence of factor II Leiden (p< 0.02) while factor V Leiden prevalence does not differ. Numerous other differences covering a wide range of proteins of the haemostaseome may result in an overall different genetic risk for venous thromboembolism.