Intracellular Accumulation and Secretion of YKL-40 (CHI3L1) in the Course of DMSO-Induced HL-60 Cell Differentiation

YKL-40 (CHI3L1) is a matrix glycoprotein stored in human neutrophil-specific granules and released upon activation. While it is implicated in inflammation, cancer progression, and cell differentiation, its exact physiological role remains unclear. This study investigated the intracellular expression and secretion of YKL-40 by untreated and DMSO-treated HL-60 cells in association with surface expression of CD11b and CD66b throughout the differentiation process (up to 120 h). Secreted YKL-40 protein and mRNA levels of YKL-40, CD66b, and CD11b were measured by ELISA and quantitative RT-PCR, respectively. The intracellular YKL-40 and surface CD11b and CD66b expression were assessed by flow cytometry. A significant increase in CD11b expression confirmed DMSO-induced differentiation of HL-60 cells. Upon DMSO stimulation, YKL-40 mRNA expression increased in a time-dependent manner, unlike CD66b. The lack of CD66b (a granulocyte maturation and activation marker) on the surface of HL-60 cells might suggest that DMSO treatment did not induce full maturation or activation. The intracellular YKL-40 protein expression was increasing up to 96 h of DMSO treatment and then declined. YKL-40 secretion into the culture medium was detectable only at later time points (96 and 120 h), which was correlated with a decreased proliferation of DMSO-treated HL-60 cells. These findings suggest sequential changes in YKL-40 production and secretion during DMSO-induced differentiation of HL-60 cells and might contribute to a better understanding of YKL-40's involvement in both physiological processes and disease development, including multiple sclerosis.

Prognostic significance of IKZF1 deletions and IKZF1plus profile in children with B-cell precursor acute lymphoblastic leukemia treated according to the ALL-IC BFM 2009 protocol

The strongest predictors of outcome in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) are minimal residual disease (MRD) and specific molecular abnormalities. One unfavorable prognostic factor is the presence of IKZF1 gene aberrations, particularly when co-occurring with high MRD level at the end of induction treatment. The present study determines the predictive value of a recently-defined IKZF1-plus (IKZF1^plus ) microdeletion profile in 373 children with BCP-ALL treated according to the ALL-IC BFM 2009 protocol. IKZF1-wild type (IKZF1^wt ) patients demonstrated lower leukemic burden parameters than those carrying IKZF1 deletion (IKZF1^del [n=26, 7.0%]) or IKZF1^plus pattern (n=34, 9.1%): i) median blast percentage at diagnosis (78.0% vs. 86.9% vs. 86.0%; p=0.021); ii) median MRD level at day 15 of induction protocol (0.3% vs. 2.1% vs. 0.8%; p=0.011); iii) poor steroid response (7.6% vs. 26.5% vs. 12.5%; p=0.010). MRD level at day 33 (MRD33) exceeding 10^-4 was more frequently observed in both the IKZF1^del and IKZF1^plus subgroups than in IKZF1^wt patients (n=9 [36.0%] vs. n=13 [41.9%] vs. n=70 [24.0%], p=0.051). IKZF1^plus individuals showed a tendency for a lower MRD reduction between day 15 and 33 compared to IKZF1^del patients (p=0.124). IKZF1^del and IKZF1^plus patients showed decreased relapse-free survival (HR [95%CI] for IKZF1^wt as reference=2.72 [1.21-6.11] and 2.00 [0.87-4.49], respectively, p=0.023). Both genetic markers including IKZF1^del and IKZF1^plus microdeletion profile provide additional predictive value of treatment outcome in childhood BCP-ALL and may contribute to more efficient patient stratification; the same is true in MRD guided protocols, which are based on flow cytometric measurements on day 15 of induction protocol. This article is protected by copyright. All rights reserved.

Biochemical and cardiovascular predictors of PIMS-TS risk in children after COVID-19 recovery: preliminary results of the LATE-COVID-Kids Study

INTRODUCTION

We aimed to characterize biochemical and cardiovascular predictors of the paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) risk based on the data from the LATE-COVID-Kids study.

METHODS

148 consecutive COVID-19 convalescents hospitalized for the clinical evaluation after the acute phase of COVID-19 were classified into two groups related to symptoms: 33 children finally diagnosed with PIMS-TS and 115 children without PIMS-TS (control group).

RESULTS

PIMS-TS children were significantly younger (6.79 ±4.57 vs. 9.10 ±4.94 years). After adjustment, in comparison to those without, PIMS-TS children had a higher level of antithrombin III (111 ±9.30 vs. 105 ±11.4), higher heart rate (HR)/min (100 (89.0-111) vs. 90 (79.7-100)) and sinus rhythm (p = 0.03) but lower PQ interval (p = 0.02) on admission to hospital. The lymphocytes (absolute count and percentage) were significantly higher in children with PIMS-TS, and the opposite results were obtained for IgA and neutrophils. Furthermore, children with PIMS-TS had a higher level of thyroid stimulating hormone (2.76 (2.16-4.18) vs. 2.36 (1.73-2.83)) and red cell distribution width (p < 0.005) compared to those without.

CONCLUSIONS

It is the first data on the possible predictors of PIMS-TS risk in the Long-COVID period. These results need to be further validated to next create the PIMS SCORE algorithm, which might enable the effective prediction of children with the risk of PIMS-TS occurrence after COVID-19 recovery.

Biochemical and cardiovascular predictors of PIMS risk in children after COVID-19 recovery =- the results of the LATE COVID Kids study

Background

Unfortunately, the number of children with the pediatric inflammatory multisystem syndrome (PIMS) associated with previous coronavirus disease has been increasing significantly.

Purpose

The aim of the present study was to characterize biochemical and cardiovascular predictors of PIMS risk in children recovered from COVID-19 based on the data from the LATE-COVID-Kids study (NCT04799444).

Methods

131 consecutive COVID-19 convalescents (mean age: 8.89±4.91; 67 boys and 64 girls) hospitalized for the clinical evaluation after the acute phase of the COVID-19 were classified into two groups related to symptoms: 29 children finally diagnosed with PIMS and 102 children with no-PIMS. All patients had confirmed coronavirus infection based on the positive results of nucleic acid test (RT-PCR - reverse transcriptase-polymerase chain), and they were serologically tested for antibodies against SARS-CoV-2. They had detailed laboratory testing, electrocardiography, and echocardiography.

Results

The time from COVID-19 recovery was from 1 to 10 months (median 4.0 [3.00–5.00] months). Children with PIMS were significantly younger in comparison to those without (6.60±4.50 vs 9.50±4.80 years, respectively; p=0,005). In comparison to non-PIMS group, children with PIMS had higher level of antithrombin III (111±7.23 vs. 104±10.9; p=0.0015), CK-MB (29.0 [18.5–36.0] vs. 21.0 [15.0–30.7]; p=0.03) and heart rate [HR]/min (100 [89.0–112] vs. 90.0 [79.0–100]; p=0.006) but lower PQ interval (120 [110–120] vs. 130 [120–140]; p=0.023) on admission to hospital. Moreover, the immunological parameters: IgA and neutrophils were lower in children with PIMS vs. no-PIMS (0.69 [0.47–0.85] vs. 1.19 [0.71–1.50]; p=0.0001 and 37.4%±13.3 vs. 43.0±11.6; p=0.0045, respectively), but lymphocytes were significantly higher (50.6±13.6 vs. 43.7±10.9; p=0.002). Some acid-base balance parameters were higher in children following PIMS vs. no-PIMS children group: pCO2 (41.30±5.70 vs. 45.0±7.00; p=0.019), pO2 (50.1 [38.4–59.7] vs. 37.8 [27.9–49.9]; p=0.007), and O2Sat (84.2 [69.3–90.6] vs. 64.2 [44.3–82.6]; p=0.004); however, concentration of HCO3- (23.6 [22.2–24.4] vs. 24.3 [22.8–26.2]; p=0.023) was lower in group of PIMS children.

Conclusions

Based on our best knowledge, it is the first data on the possible predictors of PIMS risk in children recovered from COVID-19. We showed that children with PIMS have significantly higher levels of antithrombin III, CK-MB, HR, as well as lymphocytes, pCO2, pO2 and O2Sat on admission to hospital and lower levels of PQ interval, IgA, neutrophils and concentration of HCO3. We continue our research to confirm these results and to create the PIMS SCORE algorithm to allow prediction of children with the risk of PIMS occurrence after COVID-19 recovery.

Funding Acknowledgement

Type of funding sources: None.

A multistep approach to the genotype-phenotype analysis of Polish patients with tuberous sclerosis complex

The aim of this study was to evaluate a cost-effective diagnostic strategy for identification of casual variants for tuberous sclerosis complex (TSC) in the Polish population and to correlate the genetic results with selected phenotypic features. Fifty-five patients, aged 3-44 years, with a clinical diagnosis of TSC were enrolled into the study. All patients received a three-step analysis: next generation sequencing screening (NGS), multiplex ligation-dependent probe amplification (MLPA) and deep sequencing. This multistep approach obtained positive results in 51/55 (93%) patients: of the 51 positives TSC1 variants were observed in 16 (31%) and TSC2 variants in 35 (69%); these included 13 novel variants and two patients with mosaicism. Four patients (7%) had no mutation identified (NMI). Among the TSC1 gene variants, there were five nonsense, four frameshift, three large deletions, two missense and two splicing variants. For the TSC2 gene, 11 were missense, eight splicing, six frameshift, four large deletions, two in-frame deletions and four nonsense variants. The patients with TSC2 changes had their clinical diagnosis of TSC at a younger age than those with TSC1 changes (one year vs three years, p = 0.041). The TSC2 group demonstrated a higher number of major symptoms per patient (p = 0.04). Subependymal giant cell astrocytoma with concomitance of other brain lesions was more common in patients with missense mutations in either gene (23% vs 0%, p = 0.02). Such a multistep molecular diagnostic strategy could increase the possibility of detecting causal variants for TSC and may allow detection of mosaicism at low levels. Missense pathogenic variants in TSC1 or TSC2 gene might be associated with a higher risk of brain lesions.

Nanoparticles for Directed Immunomodulation: Mannose-Functionalized Glycodendrimers Induce Interleukin-8 in Myeloid Cell Lines

New therapeutic strategies for personalized medicine need to involve innovative pharmaceutical tools, for example, modular nanoparticles designed for direct immunomodulatory properties. We synthesized mannose-functionalized poly(propyleneimine) glycodendrimers with a novel architecture, where freely accessible mannose moieties are presented on poly(ethylene glycol)-based linkers embedded within an open-shell maltose coating. This design enhanced glycodendrimer bioactivity and led to complex functional effects in myeloid cells, with specific induction of interleukin-8 expression by mannose glycodendrimers detected in HL-60 and THP-1 cells. We concentrated on explaining the molecular mechanism of this phenomenon, which turned out to be different in both investigated cell lines: in HL-60 cells, transcriptional activation via AP-1 binding to the promoter predominated, while in THP-1 cells (which initially expressed less IL-8), induction was mediated mainly by mRNA stabilization. The success of directed immunomodulation, with synthetic design guided by assumptions about mannose-modified dendrimers as exogenous regulators of pro-inflammatory chemokine levels, opens new possibilities for designing bioactive nanoparticles.

COVID-19 and cardiovascular complications - preliminary results of the LATE-COVID study

INTRODUCTION

Coronavirus disease 2019 (COVID-19) may affect many organs and may be responsible for numerous complications including cardiovascular problems.

METHODS

We analysed consecutive patients (n = 51) admitted to the cardiology department between 1st October 2020 and 31st January 2021 due to symptoms which might have reflected cardiovascular complications following COVID-19. We collected data concerning clinical characteristics, results of laboratory tests, echocardiography and 24-hour ambulatory ECG recording.

RESULTS

The post-COVID-19 complications appeared 1-4 months after disease recovery. Severe cardiovascular complications were observed in 27.5% of hospitalized patients. In comparison to those with mild complications, patients with severe complications had significantly higher prevalence of diabetes (36 vs. 8%; p = 0.01), decrease in ejection fraction (36% vs. 0%, p < 0.001), higher resting heart rate at admission (85 vs. 72 bpm; p < 0.001), and higher levels of C-reactive protein (p = 0.02) and troponin T (17.9 vs. 4.2 pg/ml; p = 0.01). Dyspnoea and exercise intolerance were also more frequent in patients with severe complications.

CONCLUSIONS

Diabetes, elevated level of CRP and troponin, heart rate variability parameters and worsening of left ventricular ejection fraction are related to the severity of cardiovascular complications following COVID-19 infection.

Six molecular patterns leading to hemophilia A phenotype in 18 females from Poland

INTRODUCTION

Female hemophilia is an intriguing rare disorder and few larger reports on its genetic etiology are available. While historically the diagnosis was satisfactorily reached by factor VIII activity assays, the clinical and potentially therapeutic heterogeneity of female hemophilia calls for comprehensive molecular diagnosis in each case. Currently, the genetic investigations are not a part of routine, state-funded, diagnostics in Poland, and thus molecular epidemiological data are missing.

AIM

We set out to perform a comprehensive genetic analysis of Polish females with hemophilia A.

PATIENTS/METHODS

Eighteen females with hemophilia A (including 2 with severe and 5 with moderate hemophilia phenotype) consented for genetic diagnostics. To establish F8 mutations, we used next-generation sequencing of a panel of genes associated with hematological disorders, standard assays for recurrent intragenic F8 inversions and MLPA when deletions were suspected. When appropriate we also used karyotyping, genomic microarrays and X chromosome inactivation assays.

RESULTS

While abnormally skewed X-chromosome inactivation combined with a F8 variant on the active allele was, as expected, the most common genetic etiology, a number of other genetic scenarios were unraveled. This included: misdiagnosis (molecular diagnosis of vWd), Turner syndrome, compound heterozygosity and androgen insensitivity syndrome (a phenotypical 46,XY female with a novel androgen receptor gene mutation). We report 3 novel F8 mutations.

CONCLUSION

Every case of female hemophilia warrants full genomic diagnostics, as this may change the diagnosis or reveal broader morbidity than a coagulation disorder (Turner syndrome, androgen insensitivity, or cardiovascular morbidity that we described previously in a SHAM syndrome carrier).

3-Bromopyruvate induces expression of antioxidant genes

An alkylating compound, 3-bromopyruvic acid (3-3-bromopyruvic acid (BP)) is a promising anti-cancer agent, potentially able to act on multidrug-resistant cells. Its action has been attributed mainly to inhibition of glycolysis. This compound induces also oxidative stress at a cellular level. The effects of 3-BP on gene expression have not been studied although they may determine the survival of cells exposed to 3-BP. The aim of this paper was to examine the effect 3-BP on gene expression pattern in breast MCF-7 cancer cells. Detection of the differences in gene expression was performed using microarrays and dysregulated genes were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Exposure of cells to 100 µM 3-BP for 6, 12 and 24 increased expression and diminished expression of 39 and 6 genes, respectively. Among the induced genes, 22 belong to general cellular stress response genes, maintenance genes involved in redox homeostasis, responding to oxidative stress (among them metallothioneins, low-molecular-weight thiol homeostasis enzymes and genes coding for NAD(P)H-dependent oxidoreductases operating on complex organic substrates, including aldo-keto reductases). These results demonstrate that transient oxidative stress in cells exposed to 3-BP is followed by antioxidant response.

Glycodendrimer Nanocarriers for Direct Delivery of Fludarabine Triphosphate to Leukemic Cells: Improved Pharmacokinetics and Pharmacodynamics of Fludarabine

Fludarabine, a nucleoside analogue antimetabolite, has complicated pharmacokinetics requiring facilitated transmembrane transport and intracellular conversion to triphosphate nucleotide form (Ara-FATP), causing it to be susceptible to emergence of drug resistance. We are testing a promising strategy to improve its clinical efficacy by direct delivery of Ara-FATP utilizing a biocompatible glycodendrimer nanocarrier system. Here, we present results of a proof-of-concept experiment in several in vitro-cultured leukemic cell lines (CCRF, THP-1, U937) using noncovalent complexes of maltose-modified poly(propyleneimine) dendrimer and fludarabine triphosphate. We show that Ara-FATP has limited cytotoxic activity toward investigated cells relative to free nucleoside (Ara-FA), but complexation with the glycodendrimer (which does not otherwise influence cellular metabolism) drastically increases its toxicity. Moreover, we show that transport via hENT1 is a limiting step in Ara-FA toxicity, while complexation with dendrimer allows Ara-FATP to kill cells even in the presence of a hENT1 inhibitor. Thus, the use of glycodendrimers for drug delivery would allow us to circumvent naturally occurring drug resistance due to decreased transporter activity. Finally, we demonstrate that complex formation does not change the advantageous multifactorial intracellular pharmacodynamics of Ara-FATP, preserving its high capability to inhibit DNA and RNA synthesis and induce apoptosis via the intrinsic pathway. In comparison to other nucleoside analogue drugs, fludarabine is hereby demonstrated to be an optimal candidate for maltose glycodendrimer-mediated drug delivery in antileukemic therapy.

Sugar-Modified Poly(propylene imine) Dendrimers Stimulate the NF-κB Pathway in a Myeloid Cell Line

Purpose

Fourth-generation poly(propylene imine) dendrimers fully surface-modified by maltose (dense shell, PPI-m DS) were shown to be biocompatible in cellular models, which is important for their application in drug delivery. We decided to verify also their inherent bioactivity, including immunomodulatory activity, for potential clinical applications. We tested their effects on the THP-1 monocytic cell line model of innate immunity effectors.

Methods

To estimate the cytotoxicity of dendrimers the reasazurin assay was performed. The expression level of NF-κB targets: IGFBP3, TNFAIP3 and TNF was determined by quantitative real-time RT-PCR. Measurement of NF-κB p65 translocation from cytoplasm to nucleus was conducted with a high-content screening platform and binding of NF-κB to a consensus DNA probe was determined by electrophoretic mobility shift assay. The cytokine assay was performed to measure protein concentration of TNFalpha and IL-4.

Results

We found that PPI-m DS did not impact THP-1 viability and growth even at high concentrations (up to 100 μM). They also did not induce expression of genes for important signaling pathways: Jak/STAT, Keap1/Nrf2 and ER stress. However, high concentrations of 4th generation PPI-m DS (25–100 μM), but not their 3rd generation counterparts, induced nuclear translocation of p65 NF-κB protein and its DNA-binding activity, leading to NF-κB-dependent increased expression of mRNA for NF-κB targets: IGFBP3, TNFAIP3 and TNF. However, no increase in pro-inflammatory cytokine secretion was detected.

Conclusion

We conclude that maltose-modified PPI dendrimers of specific size could exert a modest immunomodulatory effect, which may be advantageous in clinical applications (e.g. adjuvant effect in anti-cancer vaccines).

The impact of multiple sclerosis relapse treatment on migration of effector T cells--Preliminary study

Migration of inflammatory cells from the blood to the central nervous system (CNS) is crucial for development of multiple sclerosis (MS). Inhibition of this process would allow to control disease activity. The first step confirming this approach would be the analysis of the impact of effective MS relapse therapy on migration of effector T cells. The aim of the study was to analyze the influence of methylprednisolone (MP) on the migratory activity of effector CD4+ T cells from MS patients. Moreover, to study the potential mechanism of this process we studied expression of chemokine receptors on migrating cells.

MATERIAL AND METHODS

Peripheral blood samples were obtained from relapsing-remitting MS (RR-MS) patients during relapse (n=23) and from control group (n=23). After isolation CD4+ T cells were incubated with various concentrations of MP. Then they were stimulated in chemotaxis assay with chemokines CCL3 or CXCL10 or were used to CCR1 and CXCR3 expression analysis.

RESULTS

CXCL10- and CCL3-stimulated migration of CD4+ T cells was significantly increased in MS. MP was able to reduce in vitro migration of effector T cells induced by CXCL10, but not by CCL3. Inhibition by MP was dose-dependent. Expression of analyzed chemokine receptors was unaltered after MP incubation.

CONCLUSIONS

MP reduced CD4+ T cells migration induced by CXCL10 without affecting CXCR3 expression. These observations demonstrate one of the potential mechanisms of MP action in MS, distinct from inducing cell apoptosis, and suggests the new targets for development of more effective MS treatments.

Central Nervous System and Peripheral Expression of CCL19, CCL21 and Their Receptor CCR7 in Experimental Model of Multiple Sclerosis

It is well documented that inflammatory chemokines play a significant role in the development of multiple sclerosis (MS) and its model, experimental autoimmune encephalomyelitis (EAE). Recently, the involvement of homeostatic (or lymphoid) chemokines in the pathogenesis of autoimmune diseases has become an object of intensive study. In this work, quantitative analysis of CCL19, CCL21 and CCR7 expression in the central nervous system (CNS), as well as in inflammatory mononuclear cells isolated from several organs during the first attack, remission and the second attack of chronic-relapsing EAE (ChREAE), was performed. Using real-time PCR, RNAse Protection Assay and immunohistochemistry, the expression of both chemokines, as well as of their common receptor CCR7, was analyzed in the brain, spleen, lymph nodes and peripheral blood mononuclear cells. Increased expression of CCL19 and CCL21 was observed mostly in mononuclear inflammatory cells isolated from the CNS during active ChREAE. At the same time the expression of CCR7 in blood mononuclear leukocytes was reduced. This observation extends our current knowledge about the possible role of chemokines CCL19, CCL21 and their receptor CCR7 in the pathogenesis of ChREAE and, by extension, MS.