Cells In Peripheral Blood Of Patients Research Articles

Abstract 5261: Immunologic signatures of peripheral blood cells in patients with advanced pancreatic cancer under lenvatinib-pembrolizumab maintenance therapy

Abstract Background: The treatment of pancreatic cancer is limited by chemotherapy toxicities which impacts quality of life. This is a phase 2 clinical trial of lenvatinib and pembrolizumab as maintenance therapy in patients with advanced pancreatic cancer. We observed preclinical activity of this combination in pancreatic mouse models. We hypothesize that this combination may address unmet needs to minimize toxicities associated with standard treatments, stimulate anti-tumor T cell immunity, and improve the progression free and overall survival. Exploratory studies aim to characterize immune-related systemic changes in peripheral blood over the course of therapy and to identify global changes in expression of tumor-related genes in needle biopsy samples of liver metastatic lesions. Methods: Multiplex gene expression analysis of unsorted peripheral blood mononuclear cells (PBMC) was performed using PanCancer Immune Profiling Panel on NanoString nCounter platform. PBMC samples from pre- through week 32 of treatment were assessed for differential expression of 730 immune profiling genes defining T cell functions and associated immune categories. Results: PBMC immune profiling from 4/5 patients show a distinctive pattern of increased activation of T cells during the first 9 weeks of treatment followed by a sharp inhibition starting at weeks 9-12 after 3-4 cycles of treatment (CD3E, CD247, LCK, TBX1, TCF7, STAT4, IL2RG). Subsequent upregulation of macrophage-derived scavenger, inflammatory, and immunosuppressive gene expression patterns continued for the remainder of treatment (CD14, MSR1, MARCO, CD68, TGFB1, IL10RA). The median PFS of first 10 patients was 21.5 (9-32) weeks. Conclusions: Immunotherapy resistance may be related to rapidly developing terminal differentiation and unresponsiveness of T cells in parallel with upregulation of macrophage-derived inflammatory and immunosuppressive processes. Studies are on-going to prevent inhibition of the T-cells. Citation Format: Vincent Chung, Ferdynand Kos, Edwin Manual, Shannon Dempsey, Don J. Diamond. Immunologic signatures of peripheral blood cells in patients with advanced pancreatic cancer under lenvatinib-pembrolizumab maintenance therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5261.

Comparison of the efficacy of combined budesonide and fexofenadine versus combined fluticasone propionate and fexofenadine on the expression of class-4 semaphorins and their receptors in the peripheral blood cells of patients with allergic rhinitis

BackgroundAllergic rhinitis (AR) is a common immunoglobulin (Ig) E-mediated disease. This study aimed to evaluate the gene expression levels of class 4 semaphorins and their receptors in AR patients before and after treatment with budesonide and fexofenadine (B/F) compared to fluticasone propionate and fexofenadine (FP/F). MethodsIn this study, 29 AR patients (age 34.4 ± 1.2 years, 18 men and 11 women) were treated with B/F, and 24 AR patients (age 32.8 ± 1.9 years, 15 men and 9 women) were treated with FP/F for one month. Before and after treatment, peripheral blood samples were taken from patients. The expression levels of SEMA4A, SEMA4C, SEMA4D, Plexin-B2, and Plexin-D1 genes were measured using the qPCR method. In addition, the serum levels of IgE were measured using an enzyme-linked immunosorbent assay (ELISA). ResultsThe expression levels of SEMA4A (P = 0.011), 4C (P = 0.017), Plexin-B2 (P = 0.0005), and Plexin-D1 (P = 0.008) remarkably increased in AR patients treated with B/F. Our results show a significant reduction in the gene expression levels of SEMA4A (P = 0.002), 4C (P = 0.014), 4D (P = 0.003), Plexin-B2 (P = 0.033), and Plexin-D1 (P = 0.035) after treatment with FP/F. The serum levels of IgE increased in FP/F treated group (P = 0.017) and conversely decreased in the treated group with B/F (P = 0.019). Moreover, the percentages of eosinophils were reduced in both FP/F and B/F groups (P = 0.015 and P = 0.0001, respectively). ConclusionIn conclusion, concomitant use of fexofenadine and fluticasone propionate reduced SEMA4A, 4C, 4D, Plexin-B2, and Plexin-D1, while the SEMA4A, 4C, Plexin-B2, and Plexin-D1 gene expression levels were increased in the patient group treated with B/F.

Dynamics of Some Cytochemical Parameters of Peripheral Blood Cells in Patients With Critical Ischemia of The Lower Extremities During Revascularizing Osteotrepanation With Intramedullary Laser Irradia

Dynamics of Some Cytochemical Parameters of Peripheral Blood Cells in Patients With Critical Ischemia of The Lower Extremities During Revascularizing Osteotrepanation With Intramedullary Laser Irradia

Patients with schizophrenia and bipolar disorder display a similar global gene expression signature in whole blood that reflects elevated proportion of immature neutrophil cells with association to lipid changes

Schizophrenia (SCZ) and bipolar disorder (BD) share clinical characteristics, genetic susceptibility, and immune alterations. We aimed to identify differential transcriptional patterns in peripheral blood cells of patients with SCZ or BD versus healthy controls (HC). We analyzed microarray-based global gene expression data in whole blood from a cohort of SCZ (N = 329), BD (N = 203) and HC (N = 189). In total, 65 genes were significantly differentially expressed in SCZ and 125 in BD, as compared to HC, with similar ratio of up- and downregulated genes in both disorders. Among the top differentially expressed genes, we found an innate immunity signature that was shared between SCZ and BD, consisting of a cluster of upregulated genes (e.g., OLFM4, ELANE, BPI and MPO) that indicate an increased fraction of immature neutrophils. Several of these genes displayed sex differences in the expression pattern, and post-hoc analysis demonstrated a positive correlation with triglyceride and a negative correlation with HDL cholesterol. We found that many of the downregulated genes in SCZ and BD were associated with smoking. These findings of neutrophil granulocyte-associated transcriptome signatures in both SCZ and BD point at altered innate immunity pathways with association to lipid changes and potential for clinical translation.

Altered Expression of Long Non-Coding RNAs NEAT1, H19, and MALAT1 in Peripheral Blood ‎Cells of Patients with Allergic Rhinitis after Treatment with Pharmaceutical Combinations of ‎ Budesonide and Fexofenadine versus Fluticasone Propionate and Fexofenadine

Altered Expression of Long Non-Coding RNAs NEAT1, H19, and MALAT1 in Peripheral Blood ‎Cells of Patients with Allergic Rhinitis after Treatment with Pharmaceutical Combinations of ‎ Budesonide and Fexofenadine versus Fluticasone Propionate and Fexofenadine

Impact of Comorbidity of Bronchial Asthma and Type 2 Diabetes Mellitus on the Expression and Functional Activity of TLR2 and TLR4 Receptors

Epidemiological data indicate the active progression of various forms of diabetes mellitus in patients with bronchial asthma (BA), but little is known about the mechanisms of comorbidity formation. TLR2 and TLR4 are involved in the progression of asthma and type 2 diabetes mellitus (T2DM). These receptors are involved in the inflammatory response to Gram(+) and Gram(-) bacteria, respectively, so changes in their expression may affect the predisposition of patients to bacteremia. The aim of this study was to analyze the expression and functional activity of toll-like receptor 2 and 4 (TLR2 and TLR4) on peripheral blood cells of patients with BA, T2DM, and BA + T2DM. The expression of TLR2 and TLR4 was analyzed by flow cytometry. Whole blood samples were incubated with lipopolysaccharides from E. coli (LPS) and lipoteichoic acid from S. pyogenes (LTA). The concentration of cytokines and soluble blood proteins was determined by ELISA. Patients with comorbid diseases showed a statistically significant increase in TLR2 expression on both monocytes and neutrophils compared with healthy donors and patients with BA. We found increased expression of TLR4 on the surface of blood monocytes from patients compared to donors. The activation of blood cells of patients and donors with LPS or LTA led to an increase in the expression of "fast" pro-inflammatory cytokines (TNF-α, IL-6). In patients with BA, the average production of TNF-α in response to endotoxin was two times higher than in other studied groups. The reactions of blood cells in patients with T2DM and BA + T2DM did not differ significantly. The expression and functional activity of TLR2 and TLR4 on the blood cells of patients with comorbid disease were similar to those only in patients with T2DM. The greatest increase in the synthesis of the pro-inflammatory cytokine TNF-α in response to LPS and LTA was observed in patients with BA, which can lead to an inadequate response to bacteremia.

HUMAN PERIPHERAL BLOOD RIBONUCLEASES REACTIVATION AFTER SORPTION ON NANOPLATELETS OF LAPONITE®

Summary. Aim: to investigate the possibility of enzymatic reactivation of RNase activity of peripheral blood cells of patients with colorectal cancer (CRC) after sorption on nanoplates Laponite® RD (Lap). Objects and methods: the study was performed with the cell suspension of peripheral blood of CRC patients. Samples of cell lysates were combined with a 1% suspension of Lap nanoplates. Then RNase was extracted with 0,25 N H2SO4 or 2% solution of sodium dodecyl sulfate (DDS). The zymogram technique was used to analyze RNase activity. Results: it was found that RNases bind with nanoplates Lap and form complexes with loss of enzymatic activity. It is known that RNase can be released from the complex by extraction with 0,25 N H2SO4 or 2% sodium DDS solution. RNase is able to restore its enzymatic activity when extraction from the complex with a 2% sodium DDS solution is used. But with the extraction of 0,25 N H2SO4, the enzymatic activity is irreversibly lost. Conclusion: RNase extracted from the nanoplates Lap can be active again as an enzyme that catalyzes the cleavage of RNA and hybrid RNA/DNA molecules, depending on the method of extraction.

Pattern of Mitochondrial Respiration in Peripheral Blood Cells of Patients with Parkinson's Disease.

Mitochondria are central in the pathogenesis of Parkinson’s disease (PD), as they are involved in oxidative stress, synaptopathy, and other immunometabolic pathways. Accordingly, they are emerging as a potential neuroprotection target, although further human-based evidence is needed for therapeutic advancements. This study aims to shape the pattern of mitochondrial respiration in the blood leukocytes of PD patients in relation to both clinical features and the profile of cerebrospinal fluid (CSF) biomarkers of neurodegeneration. Mitochondrial respirometry on the peripheral blood mononucleate cells (PBMCs) of 16 PD patients and 14 controls was conducted using Seahorse Bioscience technology. Bioenergetic parameters were correlated either with standard clinical scores for motor and non-motor disturbances or with CSF levels of α-synuclein, amyloid-β peptides, and tau proteins. In PD, PBMC mitochondrial basal respiration was normal; maximal and spare respiratory capacities were both increased; and ATP production was higher, although not significantly. Maximal and spare respiratory capacity was directly correlated with disease duration, MDS-UPDRS part III and Hoehn and Yahr motor scores; spare respiratory capacity was correlated with the CSF amyloid-β-42 to amyloid-β-42/40 ratio. We provided preliminary evidence showing that mitochondrial respiratory activity increases in the PBMCs of PD patients, probably following the compensatory adaptations to disease progression, in contrast to the bases of the neuropathological substrate.

EMAP II Expression Is Increased on Peripheral Blood Cells from Non-Hodgkin Lymphoma

Tumor immune evasion is a lineament of cancer. Endothelial monocyte activating polypeptide-II (EMAP II) has been assumed to impact tumor immune escape significantly. EMAP II was first reported in the murine methylcholanthrene A-induced fibrosarcoma supernatant and identified as a tumor-derived cytokine. This study evaluated EMAP II expression in peripheral blood cells and its association with treatment outcome, lactate dehydrogenase (LDH) levels, and clinical criteria in non-Hodgkin's lymphoma (NHL) patients. EMAP II expression on different blood cells obtained from the peripheral blood of 80 NHL patients was evaluated by two-color flow cytometry. The study reported that EMAP II expression was significantly increased in peripheral blood cells in patients with NHL compared to normal volunteers (P < 0.001). Additionally, EMAP II expression levels on blood cells decreased in complete remission (CR) while they increased in relapse. This study showed coexpression of EMAP II and CD36 on peripheral lymphocytes in NHL patients but not in healthy controls (P < 0.001). EMAP II expression on blood cells was associated with increased serum LDH levels. Furthermore, the percentages of EMAP II+/CD36+ peripheral lymphocytes were significantly higher in relapse than in CR and healthy controls. Analyses revealed that higher percentages of EMAP II+CD36+ cells were positively correlated with hepatomegaly, splenomegaly, and an advanced (intermediate and high risk) NHL stage. The results assume that EMAP II might be involved in NHL development and pathogenesis.

Expression of immune checkpoints on peripheral blood cells in patients with prostate cancer

Introduction. The first clinical trials of the treatment of patients with prostate cancer with checkpoint inhibitors show that only a few patients benefit from this type of treatment. This implies the need to find predictive biomarkers that would help identify patients for whom treatment with checkpoint inhibitors could be effective. Our study aimed to assess the level of PD-1, PD-L, and CTLA-4 expression on peripheral blood mononuclear cells of patients with primary prostate cancer and to demonstrate their applicability in clinical practice. Material and methods. Fifty men with primary prostate cancer were enrolled in the study. The control group consisted of 20 healthy men. The material for the study was peripheral blood from which mononuclear cells were isolated by flow cytometry, and the expression of PD-1, CTLA-4, and PD-L1 on them was assessed. Results. High PD-L1 expression on lymphoid dendritic cells has been demonstrated in patients with prostate cancer in comparison to the control group (p = 0.015) and high PD-L1 expression has been demonstrated in the following groups: high risk (p = 0.026), T2/T3 (p = 0.011), and Gleason 7 (p = 0.027). There was no high PD-1 expression on T lymphocytes among patients with prostate cancer in comparison to the control group, but positive correlations were found between PD-1 expression on CD3+ T cells and PSA (p = 0.049), risk group (p = 0.002), and TNM (p = 0.050). Low CTLA-4 expression was found on CD3+ lymphocytes among patients with prostate cancer in comparison to the control group (p = 0.006). Conclusions. Several groups of patients with prostate cancer have been identified, showing high PD-L1 and PD-1 expression on peripheral blood mononuclear cells, and a relationship between PD-1 and PD-L1 expression and the tumor aggressiveness potential has been demonstrated. This means that the assessment of PD-1 and PD-L1 expression can be used as a prognostic and predictive biomarker in prostate cancer.

Increased mRNA Levels of ADAM17, IFITM3, and IFNE in Peripheral Blood Cells Are Present in Patients with Obesity and May Predict Severe COVID-19 Evolution.

Gene expression patterns in blood cells from SARS-CoV-2 infected individuals with different clinical phenotypes and body mass index (BMI) could help to identify possible early prognosis factors for COVID-19. We recruited patients with COVID-19 admitted in Hospital Universitari Son Espases (HUSE) between March 2020 and November 2021, and control subjects. Peripheral blood cells (PBCs) and plasma samples were obtained on hospital admission. Gene expression of candidate transcriptomic biomarkers in PBCs were compared based on the patients’ clinical status (mild, severe and critical) and BMI range (normal weight, overweight, and obesity). mRNA levels of ADAM17, IFITM3, IL6, CXCL10, CXCL11, IFNG and TYK2 were increased in PBCs of COVID-19 patients (n = 73) compared with controls (n = 47), independently of sex. Increased expression of IFNE was observed in the male patients only. PBC mRNA levels of ADAM17, IFITM3, CXCL11, and CCR2 were higher in those patients that experienced a more serious evolution during hospitalization. ADAM17, IFITM3, IL6 and IFNE were more highly expressed in PBCs of patients with obesity. Interestingly, the expression pattern of ADAM17, IFITM3 and IFNE in PBCs was related to both the severity of COVID-19 evolution and obesity status, especially in the male patients. In conclusion, gene expression in PBCs can be useful for the prognosis of COVID-19 evolution.

Intrahepatic CD69+Vδ1 T cells re-circulate in the blood of patients with metastatic colorectal cancer and limit tumor progression

BackgroundMore than 50% of all patients with colorectal cancer (CRC) develop liver metastases (CLM), a clinical condition characterized by poor prognosis and lack of reliable prognostic markers. Vδ1 cells are...

Haematological and morphological alterations in peripheral blood cells of patients with COVID -19 infections

Haematological and morphological alterations in peripheral blood cells of patients with COVID -19 infections

Expression pattern and clinical significance of β-catenin gene and protein in patients with primary malignant and benign bone tumors.

This study is aimed to unravel the status of local and circulating β-catenin in different primary bone tumors and its relevance to tumor types, severity, and chemotherapy. The β-catenin mRNA expression level and the expression of the protein (intensity level) were evaluated in tumor tissue and peripheral blood mononuclear cells of 150 patients with different types of primary bone tumors (78 malignant and 72 benign tumors) using Real-Time PCR and immunohistochemistry. The β-catenin mRNA expression level and the expression of the protein were increased in bone tumors which was positively correlated with the tumor malignancy. Amongst osteosarcoma, Ewing's Sarcoma, chondrosarcoma, osteochondroma, Giant Cell Tumor, and exostosis tumors, the osteosarcoma, and Giant Cell Tumor groups showed the highest level of β-catenin expression. The β-catenin expression in malignant bone tumors was significantly correlated with tumor grade, size, metastasis, tumor recurrent, and the level of response to chemotherapy. A similar pattern of β-catenin gene expression and its association with tumor characteristics was detected in the patient's peripheral blood cells. The simultaneous increase in the expression of the β-catenin gene and protein in tumor tissue and in circulating blood cells and its relationship with tumor severity indicates the possible promoting role of β-catenin in primary bone tumor pathogenesis.

Optimization of β-globin Stable Expression Using the Third Generation Lentiviral Vector for β-thalassemia Therapy

To provide a research basis for a safe and effective cell therapy for β-thalassemia through optimization of HS4 region of the third generation lentiviral vector for stable expression of β-globin. The human β-globin HS4 region in the third generation lentiviral expression vector was optimized to construct the lenti-HBB, and the transcription and translation of β-globin gene were analyzed by RT-PCR and Western blot after the transduction of lenti-HBB in MEL cell line. Furthermore, the erythroid differentiation of CD34+ cells which were transduced lentiviral virus carrying human β-globin from normal human umbilical cord blood cells and peripheral blood cells of patients with β-thalassemia major were confirmed by colony formation assay, cell smear assay and flow cytometry. The safety and effectiveness of the optimized lenti-HBB were verified by NSG mouse in vivo test. The human β-globin was expressed stably in the MEL cells, and CD34+ cells from health umbilical cord blood as well as PBMC from patient with β-thalassemia major transduced with lenti-HBB could be differentiated to mature red blood cells. The β-globin expression and differentiation in CD34+ cells were demonstrated successfully in the NSG mouse for about 35 months after post-transplant. Stable β-globin expression through the optimization of HS4 from CD34+ in the third generation lentiviral vector is safe and effective for patients with severe β-thalassemia and other β-globin abnormal diseases.

Single-cell profiling reveals novel cellular heterogeneity of monocytes during Hymenoptera venom allergy.

BackgroundHymenoptera stings can induce dysregulated inflammation and immediate hypersensitivity reactions including anaphylaxis. However, the molecular mechanisms underlying peripheral immune responses during Hymenoptera venom allergy (HVA) remain elusive.MethodsHere we determined the single‐cell transcriptomic profiling from highly heterogeneous peripheral blood cells in patients with HVA through unbiased single‐cell RNA sequencing and multiple models of computational analyses.ResultsThrough clustering analysis by uniform manifold approximation and projection, we revealed an increased number of monocytes in the acute phase and identified innate immune responses, leukocyte activation, and cellular detoxification as the main involved biological processes. We used filter analysis to identify that CLU that encodes clusterin was highly expressed in monocytes, and the co‐expressed genes of CLU further supported the key role of monocyte. We further used pseudo‐temporal ordering of cells and scRNA velocity analysis to delineate disease‐associated monocyte lineages and states in patients with HVA.ConclusionsOur comprehensive molecular profiling of blood samples from patients with HVA revealed previously unknown molecular changes, providing important insights into the mechanism of venom allergy and potential therapeutic targets.

Analysis of the Correlation between the Radioactive Iodine Activity and Neutrophil-to-Lymphocyte Ratio in Patients with Differentiated Thyroid Cancer.

Simple SummaryA higher tumor burden in patients with differentiated thyroid cancer undergoing radioactive iodine (131I) therapy may release into the bloodstream large amounts of 131I with a long residence time. We hypothesized that after the 131I intake, the blood concentration of 131I shows a course in several phases. To our knowledge, this research is the first of its kind. The results of the current study demonstrated a 131I blood concentration biphasic course. The time points to be considered are 46 and 69 h. 131I uptake in the residual thyroid tissue peaked after 46 h. The positive correlation between the neutrophil-to-lymphocyte ratio and administered 131I activity or the blood activity shows that the time interval between 46 and 69 h should be associated with the release of hematological inflammatory mediators, such as neutrophils and lymphocytes, to eradicate tumor cells in response to 131I therapy.Publications investigating the effect of radioactive iodine (131I) therapy on the circulating peripheral blood cells in patients with differentiated thyroid cancer (DTC) are limited to blood samples collected more than 92 h after 131I. Studies conducted on blood samples collected up to 92 h are rare due to the radioactive contamination risk. This research aimed to assess the relationship between the prescribed 131I activity, human whole blood activity, and peripheral blood cells at many time points (6, 22, 46, 69, and 92 h after 131I). The study enrolled 50 female patients with DTC who received a 131I median activity of 90.54 mCi (3.35 GBq). The neutrophil-to-lymphocyte ratio (NLR) was measured as an inflammatory marker. 131I uptake in the residual thyroid tissue peaked after 46 h. Blood activity decreased in the first 46 h and increased 69 h after the 131I intake. Blood activity was associated with the absolute lymphocyte count and the NLR at 69 h (r = −0.49 and r = 0.52, p < 0.001). Our results demonstrate that the time interval between 46 and 69 h should be associated with the release of hematological inflammatory mediators, such as neutrophils and lymphocytes, to eradicate tumor cells in response to 131I therapy.

Novel Loss-of-Function Mutations in NPR2 Cause Acromesomelic Dysplasia, Maroteaux Type.

Acromesomelic dysplasia, Maroteaux type (AMDM) is a rare skeletal dysplasia characterized by severe disproportionate short stature, short hands and feet, normal intelligence, and facial dysmorphism. Homozygous or compound heterozygous mutations in the natriuretic peptide receptor 2 (NPR2) gene produce growth-restricted phenotypes. The current study was designed to identify and characterize NPR2 loss-of-function mutations in patients with AMDM and to explore therapeutic responses to recombinant growth hormone (rhGH). NPR2 was sequenced in two Chinese patients with AMDM via next generation sequencing, and in silico structural analysis or transcript analysis of two novel variants was performed to examine putative protein changes. rhGH treatment was started for patient 1. Three NPR2 mutations were identified in two unrelated cases: two compound heterozygous mutations c.1112G>A p.(Arg371Gln) and c.2887+2T>C in patient 1 and a homozygous mutation c.329G>A p.(Arg110His) in patient 2, yielding distinct phenotypes. RNA extracted from peripheral blood cells of patient 1 showed alternatively spliced transcripts not present in control cells. Homology modeling analyses suggested that the c.1112G>A p.(Arg371Gln) mutation disrupted the binding of NPR-B homodimer to its ligand (C-type natriuretic peptide) in the extracellular domain as a result of global allosteric effects on homodimer formation. Thus, c.2887+2T>C and c.1112G>A p.(Arg371Gln) in NPR2 were loss-of-function mutations. Furthermore, rhGH therapy in patient 1 increased the patient’s height by 0.6SDS over 15 months without adversely affecting the trunk-leg proportion. The short-term growth-promoting effect was equivalent to that reported for idiopathic short stature. Overall, our findings broadened the genotypic spectrum of NPR2 mutations in individuals with AMDM and provided insights into the efficacy of rhGH in these patients.

ACE2-independent infection of T lymphocytes by SARS-CoV-2

SARS-CoV-2 induced marked lymphopenia in severe patients with COVID-19. However, whether lymphocytes are targets of viral infection is yet to be determined, although SARS-CoV-2 RNA or antigen has been identified in T cells from patients. Here, we confirmed that SARS-CoV-2 viral antigen could be detected in patient peripheral blood cells (PBCs) or postmortem lung T cells, and the infectious virus could also be detected from viral antigen-positive PBCs. We next prove that SARS-CoV-2 infects T lymphocytes, preferably activated CD4 + T cells in vitro. Upon infection, viral RNA, subgenomic RNA, viral protein or viral particle can be detected in the T cells. Furthermore, we show that the infection is spike-ACE2/TMPRSS2-independent through using ACE2 knockdown or receptor blocking experiments. Next, we demonstrate that viral antigen-positive T cells from patient undergone pronounced apoptosis. In vitro infection of T cells induced cell death that is likely in mitochondria ROS-HIF-1a-dependent pathways. Finally, we demonstrated that LFA-1, the protein exclusively expresses in multiple leukocytes, is more likely the entry molecule that mediated SARS-CoV-2 infection in T cells, compared to a list of other known receptors. Collectively, this work confirmed a SARS-CoV-2 infection of T cells, in a spike-ACE2-independent manner, which shed novel insights into the underlying mechanisms of SARS-CoV-2-induced lymphopenia in COVID-19 patients.

Influence of Telomere Length on the Achievement of Deep Molecular Response With Imatinib in Chronic Myeloid Leukemia Patients.

Tyrosine kinase inhibitors have dramatically changed the outcome of chronic myeloid leukemia (CML), and nowadays, one of the main treatment goals is the achievement of deep molecular responses (DMRs), which can eventually lead to therapy discontinuation approaches. Few biological factors at diagnosis have been associated with this level of response. Telomere length (TL) in peripheral blood cells of patients with CML has been related to disease stage, response to therapy and disease progression, but little is known about its role on DMR. In this study, we analyzed if age-adjusted TL (referred as “delta-TL”) at diagnosis of chronic phase (CP)-CML might correlate with the achievement of DMR under first-line imatinib treatment. TL from 96 CP-CML patients had been retrospectively analyzed at diagnosis by monochrome multiplex quantitative PCR. We observed that patients with longer age-adjusted telomeres at diagnosis had higher probabilities to achieve DMR with imatinib than those with shortened telomeres (P = 0.035 when delta-TL was studied as a continuous variable and P = 0.047 when categorized by the median). Moreover, patients carrying long telomeres also achieved major molecular response significantly earlier (P = 0.012). This study provides proof of concept that TL has a role in CML biology and when measured at diagnosis of CP-CML could help to identify patients likely to achieve DMR to first-line imatinib treatment.