Aptamers targeting SARS-CoV-2 nucleocapsid protein exhibit potential anti pan-coronavirus activity.

Emerging and recurrent infectious diseases caused by human coronaviruses (HCoVs) continue to pose a significant threat to global public health security. In light of this ongoing threat, the development of a broad-spectrum drug to combat HCoVs is an urgently priority. Herein, we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). These aptamers have nanomolar affinity with the nucleocapsid protein (NP) of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also show excellent binding efficiency to the N proteins of both SARS, MERS, HCoV-OC43 and -NL63 with affinity KD values of 1.31 to 135.36 nM. Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant (BA.5) with EC50 values at 2.00 nM and 41.08 nM, respectively. The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs (-229E and -HKU1). In conclusion, we have identified six aptamers with a high pan-coronavirus antiviral activity, which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.

Clearance of VWF by hepatic macrophages is critical for the protective effect of ADAMTS13 in sickle cell anemia mice.

ABSTRACT: Although it is caused by a single-nucleotide mutation in the ß-globin gene, sickle cell anemia (SCA) is a systemic disease with complex, incompletely elucidated pathologies. The mononuclear phagocyte system plays critical roles in SCA pathophysiology. However, how heterogeneous populations of hepatic macrophages contribute to SCA remains unclear. Using a combination of single-cell RNA sequencing and spatial transcriptomics via multiplexed error-robust fluorescence in situ hybridization, we identified distinct macrophage populations with diversified origins and biological functions in SCA mouse liver. We previously found that administering the von Willebrand factor (VWF)-cleaving protease ADAMTS13 alleviated vaso-occlusive episode in mice with SCA. Here, we discovered that the ADAMTS13-cleaved VWF was cleared from the circulation by a Clec4f+Marcohigh macrophage subset in a desialylation-dependent manner in the liver. In addition, sickle erythrocytes were phagocytized predominantly by Clec4f+Marcohigh macrophages. Depletion of macrophages not only abolished the protective effect of ADAMTS13 but exacerbated vaso-occlusive episode in mice with SCA. Furthermore, promoting macrophage-mediated VWF clearance reduced vaso-occlusion in SCA mice. Our study demonstrates that hepatic macrophages are important in the pathogenesis of SCA, and efficient clearance of VWF by hepatic macrophages is critical for the protective effect of ADAMTS13 in SCA mice.

BLM mutation is associated with increased tumor mutation burden and improved survival after immunotherapy across multiple cancers.

BACKGROUND: BLM encodes a RecQ DNA helicase that regulates genomic stability, and its mutations are associated with increased cancer susceptibility. Here, we show a multifaceted role of BLM mutations in tumorigenesis and immunotherapy. METHODS AND RESULTS: A total of 10,967 cancer samples from the cancer genome atlas database were analyzed, 1.6% of which harbored BLM somatic mutations. BLM mutation was found to be associated with increased tumor mutation burden and more immune-active tumor microenvironment in these patients. Moreover, clinical data of 2785 patients from nine immunotherapy studies were analyzed to study BLM mutations' impact on immunotherapy. Among them, 69 patients harbored BLM mutations, and interestingly, they had significantly higher survival probability than patients without BLM mutations. Cancer patients with BLM mutations had higher complete response and partial response rates, but lower progressive disease rate than BLM nonmutant patients. CONCLUSION: Our study shows that BLM mutation is related to improved survival after immunotherapy across multiple cancers.

Machine Learning and AI in Cancer Prognosis, Prediction, and Treatment Selection: A Critical Approach.

Cancer is a leading cause of morbidity and mortality worldwide. While progress has been made in the diagnosis, prognosis, and treatment of cancer patients, individualized and data-driven care remains a challenge. Artificial intelligence (AI), which is used to predict and automate many cancers, has emerged as a promising option for improving healthcare accuracy and patient outcomes. AI applications in oncology include risk assessment, early diagnosis, patient prognosis estimation, and treatment selection based on deep knowledge. Machine learning (ML), a subset of AI that enables computers to learn from training data, has been highly effective at predicting various types of cancer, including breast, brain, lung, liver, and prostate cancer. In fact, AI and ML have demonstrated greater accuracy in predicting cancer than clinicians. These technologies also have the potential to improve the diagnosis, prognosis, and quality of life of patients with various illnesses, not just cancer. Therefore, it is important to improve current AI and ML technologies and to develop new programs to benefit patients. This article examines the use of AI and ML algorithms in cancer prediction, including their current applications, limitations, and future prospects.

Long non-coding RNAs regulate treatment outcome in leukemia: What have we learnt recently?

Leukemia is a group of highly heterogeneous and life-threatening blood cancers that originate from abnormal hematopoietic stem cells. Multiple treatments are approved for leukemia, including chemotherapy, targeted therapy, hematopoietic stem cell transplantation, radiation therapy, and immunotherapy. Unfortunately, therapeutic resistance occurs in a substantial proportion of patients and greatly compromises the treatment efficacy of leukemia, resulting in relapse and mortality. The abnormal activity of receptor tyrosine kinases, cell membrane transporters, intracellular signal transducers, transcription factors, and anti-apoptotic proteins have been shown to contribute to the emergence of therapeutic resistance. Despite these findings, the exact mechanisms of treatment resistance are still not fully understood, which limits the development of effective measures to overcome it. Long non-coding RNAs (lncRNA) are a class of regulatory molecules that are gaining increasing attention, and lncRNA-mediated regulation of therapeutic resistance against multiple drugs for leukemia is being revealed. These dysregulated lncRNAs not only serve as potential targets to reduce resistance but also might improve treatment response prediction and individualized treatment decision. Here, we summarize the recent findings on lncRNA-mediated regulation of therapeutic resistance in leukemia and discuss future perspectives on how to make use of the dysregulated lncRNAs in leukemia to improve treatment outcome.

LFA-1 Activation in T-Cell Migration and Immunological Synapse Formation.

Integrin LFA-1 plays a critical role in T-cell migration and in the formation of immunological synapses. LFA-1 functions through interacting with its ligands with differing affinities: low, intermediate, and high. Most prior research has studied how LFA-1 in the high-affinity state regulates the trafficking and functions of T cells. LFA-1 is also presented in the intermediate-affinity state on T cells, however, the signaling to activate LFA-1 to the intermediate-affinity state and the role of LFA-1 in this affinity state both remain largely elusive. This review briefly summarizes the activation and roles of LFA-1 with varied ligand-binding affinities in the regulation of T-cell migration and immunological synapse formation.

Novel pathogenic variant combination in LPL causing familial chylomicronemia syndrome in an Asian family and experimental validation in vitro: a case report.

Background: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder, typically caused by biallelic pathogenic variants in the lipoprotein lipase (LPL) gene. Lipoprotein lipase, encoded by the LPL gene, catalyzes the hydrolysis of triglycerides, and its deficiency or dysfunction can lead to chylomicronemia and potentially fatal recurrent acute pancreatitis. Case Description: Here, we report an Asian child with FCS due to compound heterozygous LPL variants. The 4-year-old patient presented with splenomegaly and severe hypertriglyceridemia, specifically chylomicronemia which resulted in abnormal coagulation measured by a turbidity-based assay. Based on the clinical features and family history, the diagnosis of FCS was suspected, and confirmed by the identification of compound heterozygous variants in the LPL gene (c.461A>G; p.His154Arg and c.788T>A; p.Leu263Gln) in the patient, inheriting one from each parent. According to the clinical and genetic findings, the patient was diagnosed with FCS. In vitro experimental validation found that the LPL p.H154R variant reduced the expression of lipoprotein lipase and decreased its lipolytic activity, while the LPL p.L263Q variant mainly impaired its lipolytic activity. Conclusions: FCS was molecularly diagnosed using whole exome sequencing in the case presented. When interpreting abnormal coagulation profiles measured by turbidity-based assay, the possibility of lipemic blood (or chylomicronemia) should be considered and the presence of this phenomenon might indicate the diagnosis of FCS. In vitro experiments showed that the two LPL variants impaired lipoprotein lipase expression and/or function making them likely to be pathogenic.

Current therapeutic strategies and perspectives in refractory ITP: What have we learned recently?

Immune thrombocytopenia (ITP) is an acquired autoimmune bleeding disorder featured by increased platelet destruction and deficient megakaryocyte maturation. First-line treatments include corticosteroids, intravenous immunoglobulin and intravenous anti-D immunoglobulin. Second-line treatments consist of rituximab, thrombopoietin receptor agonists and splenectomy. Although most patients benefit from these treatments, an individualized treatment approach is warranted due to the large heterogeneity among ITP patients. In addition, ITP patients may relapse and there remains a subset of patients who become refractory to treatments. The management of these refractory patients is still a challenge. This review aims to summarize emerging therapeutic approaches for refractory ITP in several categories according to their different targets, including macrophages, platelets/megakaryocytes, T cells, B cells, and endothelial cells. Moreover, current management strategies and combination regimens of refractory ITP are also discussed.

Endothelial VWF is critical for the pathogenesis of vaso-occlusive episode in a mouse model of sickle cell disease.

Vaso-occlusive episode (VOE) is a common and critical complication of sickle cell disease (SCD). Its pathogenesis is incompletely understood. von Willebrand factor (VWF), a multimeric plasma hemostatic protein synthesized and secreted by endothelial cells and platelets, is increased during a VOE. However, whether and how VWF contributes to the pathogenesis of VOE is not fully understood. In this study, we found increased VWF levels during tumor necrosis factor (TNF)-induced VOE in a humanized mouse model of SCD. Deletion of endothelial VWF decreased hemolysis, vascular occlusion, and organ damage caused by TNF-induced VOE in SCD mice. Moreover, administering ADAMTS13, the VWF-cleaving plasma protease, reduced plasma VWF levels, decreased inflammation and vaso-occlusion, and alleviated organ damage during VOE. These data suggest that promoting VWF cleavage via ADAMTS13 may be an effective treatment for reducing hemolysis, inflammation, and vaso-occlusion during VOE.

Identification and validation of a siglec-based and aging-related 9-gene signature for predicting prognosis in acute myeloid leukemia patients.

BACKGROUND: Acute myeloid leukemia (AML) is a group of highly heterogenous and aggressive blood cancer. Despite recent progress in its diagnosis and treatment, patient outcome is variable and drug resistance results in increased mortality. The siglec family plays an important role in tumorigenesis and aging. Increasing age is a risk factor for AML and cellular aging contributes to leukemogenesis via various pathways. METHODS: The differential expression of the siglec family was compared between 151 AML patients and 70 healthy controls, with their information downloaded from TCGA and GTEx databases, respectively. How siglec expression correlated to AML patient clinical features, immune cell infiltration, drug resistance and survival outcome was analyzed. Differentially expressed genes in AML patients with low- and high-expressed siglec9 and siglec14 were analyzed and functionally enriched. The aging-related gene set was merged with the differentially expressed genes in AML patients with low and high expression of siglec9, and merged genes were subjected to lasso regression analysis to construct a novel siglec-based and aging-related prognostic model. The prediction model was validated using a validation cohort from GEO database (GSE106291). RESULTS: The expression levels of all siglec members were significantly altered in AML. The expression of siglecs was significantly correlated with AML patient clinical features, immune cell infiltration, drug resistance, and survival outcome. Based on the differentially expressed genes and aging-related gene set, we developed a 9-gene prognostic model and decision curve analysis revealed the net benefit generated by our prediction model. The siglec-based and aging-related 9-gene prognostic model was tested using a validation data set, in which AML patients with higher risk scores had significantly reduced survival probability. Time-dependent receiver operating characteristic curve and nomogram were plotted and showed the diagnostic accuracy and predictive value of our 9-gene prognostic model, respectively. CONCLUSIONS: Overall, our study indicates the important role of siglec family in AML and the good performance of our novel siglec-based and aging-related 9-gene signature in predicting AML patient outcome.

Deletion of platelet CLEC-2 decreases GPIbα-mediated integrin αIIbß3 activation and decreases thrombosis in TTP.

Microvascular thrombosis in patients with thrombotic thrombocytopenic purpura (TTP) is initiated by GPIbα-mediated platelet binding to von Willebrand factor (VWF). Binding of VWF to GPIbα causes activation of the platelet surface integrin αIIbß3. However, the mechanism of GPIbα-initiated activation of αIIbß3 and its clinical importance for microvascular thrombosis remain elusive. Deletion of platelet C-type lectin-like receptor 2 (CLEC-2) did not prevent VWF binding to platelets but specifically inhibited platelet aggregation induced by VWF binding in mice. Deletion of platelet CLEC-2 also inhibited αIIbß3 activation induced by the binding of VWF to GPIbα. Using a mouse model of TTP, which was created by infusion of anti-mouse ADAMTS13 monoclonal antibodies followed by infusion of VWF, we found that deletion of platelet CLEC-2 decreased pulmonary arterial thrombosis and the severity of thrombocytopenia. Importantly, prophylactic oral administration of aspirin, an inhibitor of platelet activation, and therapeutic treatment of the TTP mice with eptifibatide, an integrin αIIbß3 antagonist, reduced pulmonary arterial thrombosis in the TTP mouse model. Our observations demonstrate that GPIbα-mediated activation of integrin αIIbß3 plays an important role in the formation of thrombosis in TTP. These observations suggest that prevention of platelet activation with aspirin may reduce the risk for thrombosis in patients with TTP.

L-SIGN is a receptor on liver sinusoidal endothelial cells for SARS-CoV-2 virus.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a pandemic. Severe disease is associated with dysfunction of multiple organs, but some infected cells do not express ACE2, the canonical entry receptor for SARS-CoV-2. Here, we report that the C-type lectin receptor L-SIGN interacted in a Ca2+-dependent manner with high-mannose-type N-glycans on the SARS-CoV-2 spike protein. We found that L-SIGN was highly expressed on human liver sinusoidal endothelial cells (LSECs) and lymph node lymphatic endothelial cells but not on blood endothelial cells. Using high-resolution confocal microscopy imaging, we detected SARS-CoV-2 viral proteins within the LSECs from liver autopsy samples from patients with COVID-19. We found that both pseudo-typed virus enveloped with SARS-CoV-2 spike protein and authentic SARS-CoV-2 virus infected L-SIGN-expressing cells relative to control cells. Moreover, blocking L-SIGN function reduced CoV-2-type infection. These results indicate that L-SIGN is a receptor for SARS-CoV-2 infection. LSECs are major sources of the clotting factors vWF and factor VIII (FVIII). LSECs from liver autopsy samples from patients with COVID-19 expressed substantially higher levels of vWF and FVIII than LSECs from uninfected liver samples. Our data demonstrate that L-SIGN is an endothelial cell receptor for SARS-CoV-2 that may contribute to COVID-19-associated coagulopathy.

NbTMP14 Is Involved in Tomato Spotted Wilt Virus Infection and Symptom Development by Interaction with the Viral NSm Protein.

Tomato spotted wilt virus (TSWV) is one of the most destructive plant viruses, causing severe losses in many important crops worldwide. The non-structural protein NSm of TSWV is a viral movement protein that induces viral symptoms. However, the molecular mechanisms by which NSm contributes to symptom development are unclear. Here, we present evidence that NSm directly interacts with Nicotiana benthamiana chloroplast thylakoid membrane protein TMP14 (NbTMP14) by yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays. The interaction between NSm and NbTMP14 led to the translocation of the NbTMP14 protein from the chloroplast to the cytoplasm in TSWV-infected plants, and overexpressing NSm decreased NbTMP14 mRNA accumulation. In addition, abnormal chloroplasts and starch accumulation were observed in TSWV-infected plants. Silencing of NbTMP14 by TRV VIGS also showed similar results to those of TSWV-infected plants. Overexpressing NbTMP14 in transgenic N. benthamiana plants impeded TSWV infection, and silencing NbTMP14 in N. benthamiana plants increased disease symptom severity and virus accumulation. To our knowledge, this is the first report showing that the plant chloroplast TMP14 protein is involved in viral infection. Knowledge of the interaction between NSm and NbTMP14 advances our understanding of the molecular mechanisms underlying TSWV symptom development and infection.

Slc35a1 deficiency causes thrombocytopenia due to impaired megakaryocytopoiesis and excessive platelet clearance in the liver.

Sialic acid is a common terminal residue of glycans on proteins and acidic sphingolipids such as gangliosides and has important biological functions. The sialylation process is controlled by more than 20 different sialyltransferases, many of which exhibit overlapping functions. Thus, it is difficult to determine the overall biological function of sialylation by targeted deletion of individual sialyltransferases. To address this issue, we established a mouse line with the Slc35a1 gene flanked by loxP sites. Slc35a1 encodes the cytidine-5'-monophosphate (CMP)-sialic acid transporter that transports CMP-sialic acid from the cytoplasm into the Golgi apparatus for sialylation. Here we report our study regarding the role of sialylation on megakaryocytes and platelets using a mouse line with significantly reduced sialylation in megakaryocytes and platelets (Plt Slc35a1­ /­). The major phenotype of Plt Slc35a1­/­ mice was thrombocytopenia. The number of bone marrow megakaryocytes in Plt Slc35a1­/­ mice was reduced, and megakaryocyte maturation was also impaired. In addition, an increased number of desialylated platelets was cleared by Küpffer cells in the liver of Plt Slc35a1­/­ mice. This study provides new insights into the role of sialylation in platelet homeostasis and the mechanisms of thrombocytopenia in diseases associated with platelet desialylation, such as immune thrombocytopenia and a rare congenital disorder of glycosylation (CDG), SLC35A1-CDG, which is caused by SLC35A1 mutations.

Ergostane steroids from the ethanol extract of Dysoxylum mollissimum.

Three new ergostane steroids, 7α-acetoxyl-ergosta-5,24(28)-diene-3ß,4ß,20S-triol (1), 7α-acetoxyl-ergosta-5,24(28)-diene-3ß,4ß-diol (2), and 7α-acetoxyl-ergosta-5,24(28)-3ß-ol (3) were isolated from the ethanol extract of stem bark of Dysoxylum mollissimum BI. Structural elucidation of all the compounds was performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. All the isolated steroids were in vitro evaluated for their anti-inflammatory activity against COX-1 and COX-2. As a result, steroids 1-3 exhibited modest selective inhibition for COX-1 (>60%).

Durable Molecular Remission in a Lymphoid BP-CML Patient Harboring T315I Mutation Treated with Anti-CD19 CAR-T Therapy.

Despite the prominent effects of BCR-ABL tyrosine kinase inhibitors (TKI) therapy in patients with chronic phase-chronic myeloid leukemia (CP-CML) and thus low incidence of blastic transformation, blast phase (BP)-CML remains a major therapeutic challenge in the TKI era. The "gatekeeper" mutation T315I in BCR-ABL1 kinase, which often coupled with a poor prognosis, is quite common and resistant to all TKIs except for ponatinib. The occurrence of T315I mutation in BP-CML makes the situation more complex. Anti-CD19 chimeric antigen receptor T cell (CAR-T) technology is a new immunotherapy which has significantly improved the efficacy of B cell hematologic malignances. Here we report a lymphoid BP-CML patient harboring T315I mutation who achieved complete molecular remission and returned to chronic phase by anti-CD19 CAR-T therapy. Our study provides a new therapeutic strategy for patients in BP-CML.

Central role of RIPK1-VDAC1 pathway on cardiac impairment in a non-human primate model of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by destructive polyarthritis and systemic complications. It increases cardiovascular morbidity and mortality. However, the mechanism underlying RA-related cardiac damage remains largely unknown. Here, we found and characterized a non-human primate (NHP) model with spontaneous RA similar to the human conditions. Compared with the control group, the cardiac function in RA monkeys showed progressively deterioration; histologically, we found significantly increased inflammatory cell infiltration, cell death, and fibrosis in RA monkey heart tissue. Mechanistically, the upregulated receptor-interacting protein kinase 1 (RIPK1) in RA monkey heart tissue bound to voltage-dependent anion-selective channel 1 (VDAC1), increased VDAC1 oligomerization, and subsequently induced cardiac cell death and functional impairment. These findings identified that RIPK1-VDAC1 pathway is a promising target to treat cardiac impairment in RA. This unique model of RA will provide a valuable tool for mechanistic and translational studies.

[Application of Next Generation Sequencing in Genetic Diagnosis of Hereditary Platelet Disorders - Review].

Hereditary platelet disorders are a heterogeneous group of disorders characterized by abnormal number or function of platelets, sometimes even involving other systems apart from blood abnormalities. The great clinical and genetic heterogeneity makes the diagnosis and treatment of hereditary platelet disorders as a huge challenge for clinicians. At present, only a small number of patients have received a clear molecular diagnosis of hereditary platelet diseases, and a lot of pathogenic genetic variations still remain unknown. The popularity of next generation sequencing (NGS) promotes the development of individualized gene sequencing. Researchers have made great progress in the field of hemostasis and thrombosis using whole genome sequencing (WGS), whole exone sequencing (WES) and target gene sequencing (TGS). The development of NGS has not only promoted the individualized molecular diagnosis of hereditary platelet diseases, but also laid a solid foundation for gene therapy in the future. In this review, the new progress of the diagnosis of platelet-related diseases by using next generation sequencing techniques, is summarized.

Atypical microdeletion in 22q11 deletion syndrome reveals new candidate causative genes: A case report and literature review.

RATIONALE: 22q11 deletion syndrome, the most common chromosomal microdeletion disease, is caused by megabase-sized deletions on chromosome 22q11.2. It is characterized by a wide spectrum of congenital anomalies in velopharyngeal and facial, cardiac, genitourinary, vertebroskeletal, respiratory, digestive, and central nervous systems. Phenotype-genotype studies have revealed several causative genes that regulate the development of the third and fourth pharyngeal arches in human. However, the exact pathogenesis of this syndrome remains unknown. Herein, we report a case of 22q11 deletion syndrome with an atypical microdeletion of 125 kb. PATIENT CONCERNS: A 15-year-old Chinese girl presented with symptoms of facial dysmorphia, cardiac defects, velopharyngeal insufficiency, splenomegaly, immunodeficiency, and thrombocytopenia. DIAGNOSES: Microarray analysis revealed a 22q11.23 deletion of 125 kb (chromosome 22: 24276973-24402263), suggesting the diagnosis of 22q11 deletion syndrome. The haploinsufficient genes included GSTT2B, GSTT2, DDTL, DDT, GSTTP1, LOC391322, GSTT1, and GSTTP2. INTERVENTIONS: The patient was administrated glucocorticoids and calcium supplements. OUTCOMES: No epistaxis or petechiae episode occurred during the follow-up; her platelet count ranged between 60 × 10 and 80 × 10/L. LESSONS: Although none of the previous reported causative genes were affected in the patient, her clinical manifestations were typical of 22q11 deletion syndrome, apart from her progressive splenomegaly. This case indicated 8 new candidate pathogenic genes for 22q11 deletion syndrome. Given that the loss of these genes was sufficient to induce 22q11DS defects, whether these genes directly influence the pathogenesis of 22q11DS or through interactions with known hotspot mutations is worthy of research.