Restoration of CD3+CD56+ NKT-like cell function by TIGIT blockade in inactive carrier and immune tolerant patients of chronic hepatitis B virus infection.

Chronic hepatitis B (CHB) virus infection, which can be divided into immune-tolerant (IT), immune-active (IA), inactive carrier (IC) phases, and HBeAg-negative hepatitis (ENEG), can induce liver cirrhosis and eventually hepatocellular carcinoma (HCC). CD3+CD56+ NKT-like cells play an important role in antiviral immune response. However, the mechanism of NKT-like cells to mediate immune tolerance remains largely elusive. In this study, we observed circulating NKT-like cells from IC and IT CHB patients were phenotypically and functionally impaired, manifested by increased expression of inhibitory receptor TIGIT and decreased capacity of secreting antiviral cytokines. Besides, TIGIT+ NKT-like cells of IC and IT CHB patients expressed lower levels of cytotoxic cytokines than the TIGIT- subset. Furthermore, increased expression of CD155, the ligand of TIGIT, on plasmacytoid dendritic cells (pDCs) was detected in IC and IT CHB patients. Importantly, the co-culture of NKT-like cells and pDCs showed that NKT-like cells restored their antiviral ability after TIGIT blockade upon HBV peptide stimulation in IC and IT CHB patients. In conclusion, our findings suggest that the TIGIT pathway may mediate immune tolerance in IT CHB patients and lead to functional impairment in IC patients, indicating that TIGIT may be a potential therapeutic checkpoint for immunotherapy of CHB patients.

Phenotypic and functional exhaustion of circulating CD3+ CD56+ NKT-like cells in colorectal cancer patients.

CD3+ CD56+ NKT-like cells are crucial to antitumor immune surveillance and defense. However, research on circulating NKT-like cells in colorectal cancer (CRC) patients is limited. This investigation selected 113 patients diagnosed with primary CRC for preoperative peripheral blood collection. The blood from 106 healthy donors at the physical examination center was acquired as a healthy control (HC). The distribution of lymphocyte subsets, immunophenotype, and functional characteristics of NKT-like cells was comprehensively evaluated. Compared to HC, primary CRC patients had considerably fewer peripheral NKT-like cells in frequency and absolute quantity, and the fraction of NKT-like cells was further reduced in patients with vascular invasion compared to those without. The NKT-like cells in CRC patients had a reduced fraction of the activating receptor CD16, up-regulated expression of inhibitory receptors LAG-3 and NKG2A, impaired production of TNF-α and IFN-γ, as well as degranulation capacity. Moreover, the increased frequency of NKG2A+ NKT-like cells and the decreased expression of activation-related molecules were significantly correlated with tumor progression. In detail, NKG2A+ NKT-like cells indicated increased PD-1 and Tim-3 and reduced TNF-α than NKG2A- subgroup. Blocking NKG2A in vitro restored cytokine secretion capacity in NKT-like cells from CRC patients. Altogether, this research revealed that circulating NKT-like cells in CRC patients exhibited suppressive phenotype and functional impairment, which was more pronounced in NKG2A+ NKT-like cells. These findings suggest that NKG2A blockade may restore anti-tumor effector function in NKT-like cells, which provides a potential target for immunotherapy in CRC patients.

Atrial natriuretic peptide T2238C gene polymorphism and the risk of cardiovascular diseases: A meta­analysis.

The present study aimed to investigate the association between atrial natriuretic peptide (ANP) T2238C (rs5065) gene polymorphism and the risk of cardiovascular disease. Relevant literature was obtained by searching databases. The odds ratios (ORs) of the ANP T2238C locus genotype distribution in the case group of cardiovascular diseases and the control group of a non-cardiovascular population were pooled using R software. Sensitivity analysis was used to verify the stability of the results. Egger's linear regression test was used to assess the publication bias of the included literature. Studies were classified according to quality assessment score of the Newcastle-Ottawa scale, year, region, sample size and underlying disease for subgroup analysis, and meta-regression analysis was performed. A total of 12 studies comprising 45,619 patients were included. ANP rs5065 mutant gene C allele was a significant risk factor for myocardial infarction relative to T allele (OR=2.55, 95% CI=1.47-4.43, P=0.0008), CC+CT genotype was a significant risk factor for cerebrovascular events relative to TT (OR=1.14, 95% CI=1.04-1.26, P=0.0048) and the mutant CC genotype was a potential risk factor for the composite cardio-cerebral vascular events (CVE) relative to CT+TT (OR=1.40, 95% CI=0.96-2.04, P=0.081). In studies fulfilling the Hardy-Weinberg equilibrium, the CC genotype was a significant risk factor for the composite CVE relative to TT (OR=2.39, 95% CI=1.40-4.10, P=0.0018) and the CC genotype was a significant risk factor for composite CVE relative to CT+TT (OR=2.41, 95% CI=1.41-4.13, P=0.0015). The P-value of the Egger's test for publication bias was 0.436, which was not statistically significant. The results of the sensitivity analysis were relatively stable. Subgroup analysis indicated that the publication year was a potential source of heterogeneity. Regression analysis was performed for the recessive model in the composite CVE and the results showed that the study region (Europe) was one of the sources of heterogeneity (P=0.016). In conclusion, ANP 2238T/C mutation may increase the risk of myocardial infarction, cerebrovascular events and composite CVE.

Tumor-infiltrating platelets promote the growth of lung adenocarcinoma.

PURPOSE: Platelets could promote tumor growth and metastasis. However, the role of platelets in different subtypes of non-small cell lung cancer (NSCLC) and platelet infiltration in local tumor tissue remain unclear. METHODS: Initially, platelet infiltration in lung adenocarcinoma (ADC) and lung squamous cell carcinoma (SCC) was estimated by CD41 expression using immunohistochemistry. Subsequently, co-incubation of NSCLC cell lines and platelets was performed to compare the ability of binding platelets. Subcutaneous tumor models were established to assess the ability of platelets to promote tumor growth. Then, RNA-seq data of NSCLC was used to identify differentially expressed genes and enriched pathways. Lastly, a clinical cohort comprising of ADC and SCC patients as well as meta-analysis was analyzed to compare the difference of coagulation associated clinical parameters. RESULTS: We found high platelet infiltration in ADC, especially of advanced disease and metastases, whereas few platelets were observed in SCC. Moreover, ADC cell lines exhibited strong ability of binding platelets compared with SCC cell lines. Platelets could also promote the growth of ADC cell lines in vivo. Furthermore, coagulation cascades and fibrinogen were upregulated in ADC. And chemical inhibition of GPIIb/IIIa-fibrinogen axis reduced the binding of ADC cells and platelets. ADC patients were also in a hypercoagulable state characterized by higher d-dimer level and shorter clotting time. Finally, meta-analysis identified a higher risk of venous thromboembolism (VTE) in ADC patients and low molecular weight heparin (LMWH) treatment was effective at reducing this risk. CONCLUSIONS: This study identified the differences of platelet infiltration and coagulation between ADC and SCC patients, which may inform the development of anticoagulation therapies for NSCLC.

Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry as Internship Teaching Content in Laboratory Medicine.

BACKGROUND: Matrix-assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) is one of the preferred detection techniques for identification of clinical microorganisms and it has the characteristics of rapid identification, simple operation, low cost, and updatable databases. For laboratory medicine undergraduates, clinical internship is an important stage for the connection of basic theoretical knowledge and clinical practice. Internship teaching choosing MALDI-TOF MS as the content will greatly increase the popularity and applicability of the new technology in the clinical microbiology laboratory. METHODS: With the help of electronic databases on the network, we conducted a systematic review. According to the purpose of research, we singled out forty papers. Latest studies on history, basic principles, clinical features, and applications of MALDI-TOF MS and the internship teaching contents introducing new technologies are summarized and focused on. In internship teaching, firstly we explain the historical development, basic principle and widespread applications of MALDI-TOF MS in the identification of clinical pathogenic microorganisms and the detection of antibiotic resistance. Subsequently, we instruct the students to perform the experimental operations, analyze the common problems, and find solutions. Finally, we highlight quality control and laboratory biosafety. RESULTS: Most of the reviews published previously report the clinical features and applications of MALDI-TOF MS and the internship teaching contents choosing other new technologies. It is the first study selecting MALDI-TOF MS technology as an internship teaching content creatively. Primary outcome is that the students understand the theoretical knowledge in detail, master the operation skills of MALDI-TOF MS quickly, and obtain excellent internship performances in the clinical internship through the internship teaching. Secondary outcome is that it is a help to cultivate medical students' train of thought for scientific research and to understand the application of the new technology in clinical testing and scientific research. CONCLUSIONS: Laboratory medicine undergraduates should cherish the opportunity to learn the new technology during the internship period and should master basic principle and operation. As internship teachers, it is necessary to introduce the new technology to students during the internship and encourage undergraduates to cultivate creative and innovative thinking of scientific research.

CUSS-Net: A Cascaded Unsupervised-Based Strategy and Supervised Network for Biomedical Image Diagnosis and Segmentation.

Biomedical image segmentation and classification are critical components in a computer-aided diagnosis system. However, various deep convolutional neural networks are trained by a single task, ignoring the potential contribution of mutually performing multiple tasks. In this paper, we propose a cascaded unsupervised-based strategy to boost the supervised CNN framework for automated white blood cell (WBC) and skin lesion segmentation and classification, called CUSS-Net. Our proposed CUSS-Net consists of an unsupervised-based strategy (US) module, an enhanced segmentation network named E-SegNet, and a mask-guided classification network called MG-ClsNet. On the one hand, the proposed US module produces coarse masks that provide a prior localization map for the proposed E-SegNet to enhance it in locating and segmenting a target object accurately. On the other hand, the enhanced coarse masks predicted by the proposed E-SegNet are then fed into the proposed MG-ClsNet for accurate classification. Moreover, a novel cascaded dense inception module is presented to capture more high-level information. Meanwhile, we adopt a hybrid loss by combining a dice loss and a cross-entropy loss to alleviate the imbalance training problem. We evaluate our proposed CUSS-Net on three public medical image datasets. Experiments show that our proposed CUSS-Net outperforms representative state-of-the-art approaches.

Dysfunction of circulating CD3+CD56+ NKT-like cells in type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is associated with increased incidence and mortality of many cancers and infectious diseases. CD3+CD56+ NKT-like cells play pivotal roles in tumor surveillance and infection control. However, little is known about potential alterations in circulating NKT-like cells in T2DM patients. In this study, we found that the frequency and absolute counts of circulating NKT-like cells were significantly lower in patients with T2DM compared to healthy volunteers. Moreover, in T2DM patients, NKT-like cells were impaired in their production of IFN-γ and TNF-α as well as degranulation capacity. The expression of activating receptor NKG2D was markedly decreased on NKT-like cells in T2DM patients, while the expression of inhibitory receptors Tim-3 and LAG-3 was upregulated. In detail, Tim-3+NKT-like cells expressed higher LAG-3 and less IFN-γ and TNF-α compared to Tim-3-NKT-like cells. Importantly, we further found that the expression of Tim-3 in NKT-like cells from T2DM patients correlated positively with glycated hemoglobin (HbA1c) and fasting blood glucose (FBG) levels, as well as with diabetes duration. In conclusion, these results indicate that NKT-like cells from T2DM patients display an exhausted phenotype and reduced functionality. Moreover, Tim-3 expression on NKT-like cells likely serves a novel biomarker for duration of T2DM.

CD8+ T cells mediate antiviral response in severe fever with thrombocytopenia syndrome.

Severe fever with thrombocytopenia syndrome (SFTS), which is caused by a novel Bunyavirus, has gradually become a threatening infectious disease in rural areas of Asia. Studies have identified a severe cytokine storm and impaired humoral immune response in SFTS. However, the cellular immune response to SFTS virus (SFTSV) infection remains largely unknown. Here we report that SFTS patients had a cytokine storm accompanied by high levels of chemokines. CD8+ T cells in peripheral blood mononuclear cells of SFTS patients exhibited a more activated phenotype and enhanced the antiviral responses. They increased the expression of CD69 and CD25, secreted a higher level of IFN-γ and granzyme, and had a stronger proliferative ability than in healthy controls. In convalescent SFTS patients, the expression of CD69 and CD25 on CD8+ T cells was reduced. In addition, we found the ratio and cellularity of CD14+ CD16+ intermediate monocytes were increased in peripheral blood of SFTS patients. Both the expression of C-X-C motif chemokine ligand 10 (CXCL10) on CD14+ CD16+ intermediate monocytes and the expression of C-X-C motif chemokine receptor 3 (CXCR3) on CD8+ T cells increased dramatically in SFTS patients. Our studies reveal a potential pathway that CD8+ T cells rapidly activate and are mostly recruited by intermediate monocytes through CXCL10 in SFTSV infection. Our results may be of clinical relevance for further treatment and discharge instructions in SFTSV infections.

A Super-resolution Guided Network for Improving Automated Thyroid Nodule Segmentation.

BACKGROUND AND OBJECTIVE: A thyroid nodule is an abnormal lump that grows in the thyroid gland, which is the early symptom of thyroid cancer. In order to diagnose and treat thyroid cancer at the earliest stage, it is desired to characterize the nodule accurately. Ultrasound thyroid nodules segmentation is a challenging task due to the speckle noise, intensity heterogeneity, low contrast and low resolution. In this paper, we propose a novel framework to improve the accuracy of thyroid nodules segmentation. METHODS: Different from previous work, a super-resolution reconstruction network is firstly constructed to upscale the resolution of the input ultrasound image. After that, our proposed N-shape network is utilized to perform the segmentation task. The guidance of super-resolution reconstruction network can make the high-frequency information of the input thyroid ultrasound image richer and more comprehensive than the original image. Our N-shape network consists of several atrous spatial pyramid pooling blocks, a multi-scale input layer, a U-shape convolutional network with attention blocks and a proposed parallel atrous convolution(PAC) module. These modules are conducive to capture context information at multiple scales so that semantic features can be fully utilized for lesion segmentation. Especially, our proposed PAC module is beneficial to further improve the segmentation by extracting high-level semantic features from different receptive fields. We use the UTNI-2021 dataset for model training, validating and testing. RESULTS: The experimental results show that our proposed method achieve a Dice value of 91.9%, a mIoU value of 87.0%, a Precision value of 88.0%, a Recall value 83.7% and a F1-score value of 84.3%, which outperforms most state-of-the-art methods. CONCLUSIONS: Our method achieves the best performance on the UTNI-2021 dataset and provides a new way of ultrasound image segmentation. We believe that our method can provide doctors with reliable auxiliary diagnosis information in clinical practice.

Corrigendum: N-Net: A novel dense fully convolutional neural network for thyroid nodule segmentation.

[This corrects the article DOI: 10.3389/fnins.2022.872601.].

N-Net: A novel dense fully convolutional neural network for thyroid nodule segmentation.

Medical image segmentation is an essential component of computer-aided diagnosis (CAD) systems. Thyroid nodule segmentation using ultrasound images is a necessary step for the early diagnosis of thyroid diseases. An encoder-decoder based deep convolutional neural network (DCNN), like U-Net architecture and its variants, has been extensively used to deal with medical image segmentation tasks. In this article, we propose a novel N-shape dense fully convolutional neural network for medical image segmentation, referred to as N-Net. The proposed framework is composed of three major components: a multi-scale input layer, an attention guidance module, and an innovative stackable dilated convolution (SDC) block. First, we apply the multi-scale input layer to construct an image pyramid, which achieves multi-level receiver field sizes and obtains rich feature representation. After that, the U-shape convolutional network is employed as the backbone structure. Moreover, we use the attention guidance module to filter the features before several skip connections, which can transfer structural information from previous feature maps to the following layers. This module can also remove noise and reduce the negative impact of the background. Finally, we propose a stackable dilated convolution (SDC) block, which is able to capture deep semantic features that may be lost in bilinear upsampling. We have evaluated the proposed N-Net framework on a thyroid nodule ultrasound image dataset (called the TNUI-2021 dataset) and the DDTI publicly available dataset. The experimental results show that our N-Net model outperforms several state-of-the-art methods in the thyroid nodule segmentation tasks.

Natural Killer Cells Induce CD8+ T Cell Dysfunction via Galectin-9/TIM-3 in Chronic Hepatitis B Virus Infection.

The antiviral response of natural killer (NK) cells and CD8+ T cells is weak in patients with chronic hepatitis B (CHB) infection. However, the specific characteristics of these cells and the association between NK cells and CD8+ T cell dysfunction is not well known. In this study, higher galectin-9 (Gal-9) expression was observed in circulating NK cells from CHB patients than from healthy controls and was found to contribute to NK cell dysfunction. In addition, circulating CD8+ T cells showed obvious dysfunction and overexpressed TIM-3, the natural receptor of Gal-9, during active CHB infection. Gal-9+ and Gal-9- NK cells from active CHB patients were sorted and cocultured with autologous CD8+ T cells. The proportion of tetramer+CD8+ T cells and the cytokines production of CD8+ T cells were lower after cocultivation with Gal-9+ than with Gal-9- NK cells. We showed that in vitro depletion of NK cells increased circulating hepatitis B virus (HBV)-specific CD8+ T cell responses in patients with active CHB infection. Because Gal-9 is increased in the serum of CHB patients, CD8+ T cells were sorted and cultured with exogenous Gal-9, resulting in lower IFN-γ, TNF-α, CD107a, and granzyme B levels, decreased expression of the activation receptor CD69, increased expression of TIM-3, and a high percentage of early apoptotic CD8+ T cells. Blocking Gal-9 or TIM-3 in vitro in a culture of peripheral blood mononuclear cells (PBMCs) stimulated with HBV peptide from active CHB patients restored CD8+ T cell function. However, blocking Gal-9 in vitro after removal of NK cells from PBMCs did not rescue CD8+ T cells exhaustion. Furthermore, NK and CD8+ T cells from active CHB patients were sorted and cocultured in vitro, and the exhaustion of CD8+ T cells were alleviated after blocking Gal-9 or TIM-3. In summary, overexpression of Gal-9 on NK cells, which interacts with TIM-3+CD8+ T cells and likely contributes to antiviral CD8+ T cell dysfunction, may be a potential target for the treatment of CHB patients.

First Study of Bacteremia Caused by Herbaspirillum huttiense in China: A Brief Research Report and Literature Review.

Bacteremia caused by Herbaspirillum huttiense (H. huttiense) is relatively rare in positive blood cultures. H. huttiense is an opportunistic bacterium in patients with cancer and cirrhosis and has also been described in immunocompromised hosts. In this study, H. huttiense was isolated from a patient with repeated chest tightness and chest pain. Smears were prepared, stained, and examined by microscopy. Single colonies were analyzed by Gram staining, matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS), 16S rRNA sequencing and Next-Generation Sequencing (NGS). Antibiotic sensitivity was assessed by agar dilution. Almost all publications on H. huttiense infections in the PubMed/ScienceDirect/EBSCO databases were reviewed and summarized. Blood sample culturing yielded white, gelatinous, and slightly raised colonies without hemolytic rings. The bacilli were found to be Gram-negative, and MS results showed 99.2% homology with H. huttiense. This was confirmed by 16S rRNA gene sequencing, phylogenetic tree analysis and NGS all of which were homologous with H. huttiense in GenBank. Antibiotic susceptibility tests were performed to determine the minimum inhibitory concentrations (MICs) of imipenem, meropenem, piperacillin-tazobactam, and levofloxacin. A comprehensive literature review revealed that H. huttiense was an emergent pathogen. After medical treatment, the patient's body temperature returned to normal. This is the first report of bacteremia caused by H. huttiense in China. The findings could improve the awareness and attention of the rare pathogenic microorganisms in China.

Liver Transplantation in Acute-on-Chronic Liver Failure: Excellent Outcome and Difficult Posttransplant Course.

Background: Acute-on-chronic liver failure (ACLF) patients have high mortality in a short period of time. This study aimed to compare the prognosis of transplanted ACLF patients to that of nontransplanted ACLF patients and decompensated cirrhosis recipients. Methods: Clinical data of 29 transplanted ACLF patients, 312 nontransplanted ACLF patients, and 60 transplanted decompensated cirrhosis patients were retrospectively collected. Propensity score matching (PSM) analysis was used to match patients between different groups. Results: After PSM, the 90-day and 1-year survival of transplanted ACLF patients was significantly longer than that of nontransplant controls. Although the 90-day survival and 1-year survival of ACLF recipients was similar to that of decompensated cirrhosis controls, ACLF recipients were found to have longer mechanical ventilation, longer intensive care unit (ICU) stay, longer hospital stay, higher incidence of tracheotomy, higher expense, and higher morbidity of complication than matched decompensated cirrhosis controls. The 90-day and 1-year survival of transplanted ACLF grade 2-3 patients was also significantly longer than that of nontransplanted controls. Conclusions: Liver transplantation can strongly improve the prognosis of ACLF patients. Despite having more burdens (including longer mechanical ventilation, longer ICU stay, higher incidence of tracheotomy, longer hospital stay, higher hospitalization expense, and higher complication morbidity), ACLF recipients can obtain similar short-term and long-term survival to decompensated cirrhosis recipients. For severe ACLF patients, liver transplantation can also significantly improve their short-term and long-term survival.

A Multi-Scale Densely Connected Convolutional Neural Network for Automated Thyroid Nodule Classification.

Automated thyroid nodule classification in ultrasound images is an important way to detect thyroid nodules and to make a more accurate diagnosis. In this paper, we propose a novel deep convolutional neural network (CNN) model, called n-ClsNet, for thyroid nodule classification. Our model consists of a multi-scale classification layer, multiple skip blocks, and a hybrid atrous convolution (HAC) block. The multi-scale classification layer first obtains multi-scale feature maps in order to make full use of image features. After that, each skip-block propagates information at different scales to learn multi-scale features for image classification. Finally, the HAC block is used to replace the downpooling layer so that the spatial information can be fully learned. We have evaluated our n-ClsNet model on the TNUI-2021 dataset. The proposed n-ClsNet achieves an average accuracy (ACC) score of 93.8% in the thyroid nodule classification task, which outperforms several representative state-of-the-art classification methods.

IL-17 exacerbates experimental autoimmune prostatitis via CXCL1/CXCL2-mediated neutrophil infiltration.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a poorly understood disease. Accumulating evidence suggests that autoimmune dysfunction is involved in the development of CP/CPPS. Interleukin-17 (IL-17) is associated with the occurrence and development of several chronic autoimmune inflammatory diseases. However, the molecular mechanisms underlying the role of IL-17 in CP/CPPS are not clear. We confirmed that IL-17 was increased in the prostate tissues of experimental autoimmune prostatitis (EAP) mice. Corresponding to the increase of IL-17, neutrophil infiltration and the levels of CXCL1 and CXCL2 (CXC chemokine ligands 1 and 2) were also increased in the prostate of EAP. Treatment of EAP mice with an IL-17-neutralizing monoclonal antibody (mAb) decreased the number of infiltrated neutrophils and CXCL1 and CXCL2 levels. Depletion of neutrophils using anti-Ly6G antibodies ameliorated the inflammatory changes and hyperalgesia caused by EAP. Fucoidan, a could potent inhibitor of neutrophil migration, also ameliorate the manifestations of EAP. Our findings suggested that IL-17 promoted the production of CXCL1 and CXCL2, which triggered neutrophil chemotaxis to prostate tissues. Fucoidan might be a potential drug for the treatment of EAP via the effective inhibition of neutrophil infiltration.

Single-cell transcriptomics reveal a unique memory-like NK cell subset that accumulates with ageing and correlates with disease severity in COVID-19.

BACKGROUND: Natural killer (NK) cells are innate lymphoid cells that mediate antitumour and antiviral responses. However, very little is known about how ageing influences human NK cells, especially at the single-cell level. METHODS: We applied single-cell sequencing (scRNA-seq) to human lymphocytes and NK cells from 4 young and 4 elderly individuals and then analysed the transcriptome data using Seurat. We detected the proportion and phenotype of NK cell subsets in peripheral blood samples from a total of 62 young and 52 elderly healthy donors by flow cytometry. We also used flow cytometry to examine the effector functions of NK cell subsets upon IFN-α/IL-12+IL-15/K562/IL-2 stimulation in vitro in peripheral blood samples from a total of 64 young and 63 elderly healthy donors. We finally studied and integrated single-cell transcriptomes of NK cells from 15 young and 41 elderly COVID-19 patients with those from 12 young and 6 elderly healthy control individuals to investigate the impacts of ageing on NK cell subsets in COVID-19 disease. RESULTS: We discovered a memory-like NK subpopulation (NK2) exhibiting the largest distribution change between elderly and young individuals among lymphocytes. Notably, we discovered a unique NK subset that was predominantly CD52+ NK2 cells (NK2.1). These memory-like NK2.1 cells accumulated with age, exhibited proinflammatory characteristics, and displayed a type I interferon response state. Integrative analyses of a large-cohort COVID-19 dataset and our datasets revealed that NK2.1 cells from elderly COVID-19 patients are enriched for type I interferon signalling, which is positively correlated with disease severity in COVID-19. CONCLUSIONS: We identified a unique memory-like NK cell subset that accumulates with ageing and correlates with disease severity in COVID-19. Our results identify memory-like NK2.1 cells as a potential target for developing immunotherapies for infectious diseases and for addressing age-related dysfunctions of the immune system.

Elevated Level of Serum Interleukin-21 and Its Influence on Disease Activity in Anti-Neutrophil Cytoplasmic Antibodies Against Myeloperoxidase-Associated Vasculitis.

Interleukin-21 (IL-21) has been shown to play an important role in the immune system. This study aimed to investigate the changes in the level of IL-21 in patients with anti-neutrophil cytoplasmic antibodies against myeloperoxidase (MPO-ANCA)-associated vasculitis (MPO-AAV), as well as explore its influence on disease activity and the potential mechanism. Flow cytometry was performed to detect the percentage of follicular helper T cells (Tfh) among CD4+T cells (Tfh%); the percentage of Tfh-expressing inducible costimulator (ICOS) among Tfh cells (ICOS+Tfh%); the percentage of Tfh-expressing programmed cell death protein 1 (PD-1) among Tfh cells (PD-1+Tfh%); and mean fluorescence intensity of Tfh-expressing ICOS or PD-1 in the peripheral blood. An enzyme-linked immunosorbent assay was used to measure the levels of serum IL-21 and MPO-ANCA. The Birmingham Vasculitis Activity Score was used to evaluate disease activity. Our results revealed that the level of IL-21 in the patient group was significantly higher than that in the healthy control group (1324.2 ± 125.3 pg/mL vs. 704.2 ± 41.1 pg/mL, P < 0.001), and it was an independent factor affecting the disease activity (P = 0.022). Thus, blocking the activity of IL-21 may represent a potential novel target for the future treatment of MPO-AAV.

The value of real-time contrast-enhanced ultrasound combined with CT enhancement in the differentiation of subtypes of renal cell carcinoma.

AIM: This study aimed to evaluate the value of real-time contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CECT) in the differential diagnosis of clear cell renal cell carcinoma (CCRCC), papillary renal cell carcinoma (PRCC), and chromophobe renal cell carcinoma (CRCC). MATERIALS AND METHODS: In the present study, 82 patients with CCRCC, 24 patients with PRCC, and 19 patients with CRCC were confirmed by pathology of the resected tumor. All patients were evaluated by CEUS and CECT before the operation. In addition, the contrast enhancement mode of CEUS and CECT and the contrast parameters of the region of interest (ROI) time-intensity curve between the lesions and the surrounding normal renal parenchyma by CEUS were compared and analyzed. RESULTS: Compared with the pathological results, the diagnostic accuracy of ultrasound in the 3 groups was 87.8% (72/82), 83.3% (20/24) and 73.7% (14/19). There was no significant difference between CEUS and CECT in the diagnostic accuracy of all groups (P>0.05). Meanwhile, compared with the surrounding renal parenchyma by CEUS, 82.5% (66/80) of CCRCC lesions showed "fast-forward and fast/slow-retrograde," while 83.3% (20/24) of PRCC, and 84.2% (16/19) showed "slow-forward and fast/slow-retrograde." Significant differences in the enhancement modes of CEUS were found among the CCRCC, PRCC, and CRCC lesions (P < 0.05). And the enhancement modes could be quantitatively analyzed by the ROI time-intensity curve of the lesion. Moreover, lesions enhanced by CECT and 74.4% (61/82) of CCRCC lesions showed "fast-forward and fast/slow-retrograde," while 66.7% (16/24) of PRCC and 84.2% (16/19) of CRCC showed "slow-forward and fast/slow-retrograde." The contrast modes and enhancement uniformity of CEUS and CECT showed no significant differences among the CCRCC, PRCC, and CRCC lesions (P > 0.05). CONCLUSION: CEUS and quantitative analysis of ROI time-intensity curve can be used for differential diagnosis of the 3 RCC subtypes. The combination of CEUS and CECT can help us differentiate RCC subtypes and is of great significance for clinical treatment strategies and prognostication.