1.Primary assessment of the diversity of Omicron sublineages and the epidemiologic features of autumn/winter 2022 COVID-19 wave in Chinese mainland.
Gang LU ; Yun LING ; Minghao JIANG ; Yun TAN ; Dong WEI ; Lu JIANG ; Shuting YU ; Fangying JIANG ; Shuai WANG ; Yao DAI ; Jinzeng WANG ; Geng WU ; Xinxin ZHANG ; Guoyu MENG ; Shengyue WANG ; Feng LIU ; Xiaohong FAN ; Saijuan CHEN
Frontiers of Medicine 2023;17(4):758-767
With the recent ongoing autumn/winter 2022 COVID-19 wave and the adjustment of public health control measures, there have been widespread SARS-CoV-2 infections in Chinese mainland. Here we have analyzed 369 viral genomes from recently diagnosed COVID-19 patients in Shanghai, identifying a large number of sublineages of the SARS-CoV-2 Omicron family. Phylogenetic analysis, coupled with contact history tracing, revealed simultaneous community transmission of two Omicron sublineages dominating the infections in some areas of China (BA.5.2 mainly in Guangzhou and Shanghai, and BF.7 mainly in Beijing) and two highly infectious sublineages recently imported from abroad (XBB and BQ.1). Publicly available data from August 31 to November 29, 2022 indicated an overall severe/critical case rate of 0.035% nationwide, while analysis of 5706 symptomatic patients treated at the Shanghai Public Health Center between September 1 and December 26, 2022 showed that 20 cases (0.35%) without comorbidities progressed into severe/critical conditions and 153 cases (2.68%) with COVID-19-exacerbated comorbidities progressed into severe/critical conditions. These observations shall alert healthcare providers to place more resources for the treatment of severe/critical cases. Furthermore, mathematical modeling predicts this autumn/winter wave might pass through major cities in China by the end of the year, whereas some middle and western provinces and rural areas would be hit by the upcoming infection wave in mid-to-late January 2023, and the duration and magnitude of upcoming outbreak could be dramatically enhanced by the extensive travels during the Spring Festival (January 21, 2023). Altogether, these preliminary data highlight the needs to allocate resources to early diagnosis and effective treatment of severe cases and the protection of vulnerable population, especially in the rural areas, to ensure the country's smooth exit from the ongoing pandemic and accelerate socio-economic recovery.
2.Revisiting China's response to coronavirus disease 2019.
Guangbiao ZHOU ; Saijuan CHEN ; Zongjiu ZHANG ; Zhu CHEN
Frontiers of Medicine 2023;17(6):1011-1013
3.A systematic survey of LU domain-containing proteins reveals a novel human gene, LY6A, which encodes the candidate ortholog of mouse Ly-6A/Sca-1 and is aberrantly expressed in pituitary tumors.
Dan LIU ; Chunhui XU ; Yanting LIU ; Wen OUYANG ; Shaojian LIN ; Aining XU ; Yuanliang ZHANG ; Yinyin XIE ; Qiuhua HUANG ; Weili ZHAO ; Zhu CHEN ; Lan WANG ; Saijuan CHEN ; Jinyan HUANG ; Zhe Bao WU ; Xiaojian SUN
Frontiers of Medicine 2023;17(3):458-475
The Ly-6 and uPAR (LU) domain-containing proteins represent a large family of cell-surface markers. In particular, mouse Ly-6A/Sca-1 is a widely used marker for various stem cells; however, its human ortholog is missing. In this study, based on a systematic survey and comparative genomic study of mouse and human LU domain-containing proteins, we identified a previously unannotated human gene encoding the candidate ortholog of mouse Ly-6A/Sca-1. This gene, hereby named LY6A, reversely overlaps with a lncRNA gene in the majority of exonic sequences. We found that LY6A is aberrantly expressed in pituitary tumors, but not in normal pituitary tissues, and may contribute to tumorigenesis. Similar to mouse Ly-6A/Sca-1, human LY6A is also upregulated by interferon, suggesting a conserved transcriptional regulatory mechanism between humans and mice. We cloned the full-length LY6A cDNA, whose encoded protein sequence, domain architecture, and exon-intron structures are all well conserved with mouse Ly-6A/Sca-1. Ectopic expression of the LY6A protein in cells demonstrates that it acts the same as mouse Ly-6A/Sca-1 in their processing and glycosylphosphatidylinositol anchoring to the cell membrane. Collectively, these studies unveil a novel human gene encoding a candidate biomarker and provide an interesting model gene for studying gene regulatory and evolutionary mechanisms.
Humans
;
Membrane Proteins/genetics*
;
Pituitary Neoplasms/genetics*
;
Biomarkers
4.Host protection against Omicron BA.2.2 sublineages by prior vaccination in spring 2022 COVID-19 outbreak in Shanghai.
Ziyu FU ; Dongguo LIANG ; Wei ZHANG ; Dongling SHI ; Yuhua MA ; Dong WEI ; Junxiang XI ; Sizhe YANG ; Xiaoguang XU ; Di TIAN ; Zhaoqing ZHU ; Mingquan GUO ; Lu JIANG ; Shuting YU ; Shuai WANG ; Fangyin JIANG ; Yun LING ; Shengyue WANG ; Saijuan CHEN ; Feng LIU ; Yun TAN ; Xiaohong FAN
Frontiers of Medicine 2023;17(3):562-575
The Omicron family of SARS-CoV-2 variants are currently driving the COVID-19 pandemic. Here we analyzed the clinical laboratory test results of 9911 Omicron BA.2.2 sublineages-infected symptomatic patients without earlier infection histories during a SARS-CoV-2 outbreak in Shanghai in spring 2022. Compared to an earlier patient cohort infected by SARS-CoV-2 prototype strains in 2020, BA.2.2 infection led to distinct fluctuations of pathophysiological markers in the peripheral blood. In particular, severe/critical cases of COVID-19 post BA.2.2 infection were associated with less pro-inflammatory macrophage activation and stronger interferon alpha response in the bronchoalveolar microenvironment. Importantly, the abnormal biomarkers were significantly subdued in individuals who had been immunized by 2 or 3 doses of SARS-CoV-2 prototype-inactivated vaccines, supporting the estimation of an overall 96.02% of protection rate against severe/critical disease in the 4854 cases in our BA.2.2 patient cohort with traceable vaccination records. Furthermore, even though age was a critical risk factor of the severity of COVID-19 post BA.2.2 infection, vaccination-elicited protection against severe/critical COVID-19 reached 90.15% in patients aged ≽ 60 years old. Together, our study delineates the pathophysiological features of Omicron BA.2.2 sublineages and demonstrates significant protection conferred by prior prototype-based inactivated vaccines.
Humans
;
Aged
;
Middle Aged
;
COVID-19/prevention & control*
;
SARS-CoV-2
;
Pandemics/prevention & control*
;
China/epidemiology*
;
Disease Outbreaks/prevention & control*
;
Vaccination
5.PathogenTrack and Yeskit: tools for identifying intracellular pathogens from single-cell RNA-sequencing datasets as illustrated by application to COVID-19.
Wei ZHANG ; Xiaoguang XU ; Ziyu FU ; Jian CHEN ; Saijuan CHEN ; Yun TAN
Frontiers of Medicine 2022;16(2):251-262
Pathogenic microbes can induce cellular dysfunction, immune response, and cause infectious disease and other diseases including cancers. However, the cellular distributions of pathogens and their impact on host cells remain rarely explored due to the limited methods. Taking advantage of single-cell RNA-sequencing (scRNA-seq) analysis, we can assess the transcriptomic features at the single-cell level. Still, the tools used to interpret pathogens (such as viruses, bacteria, and fungi) at the single-cell level remain to be explored. Here, we introduced PathogenTrack, a python-based computational pipeline that uses unmapped scRNA-seq data to identify intracellular pathogens at the single-cell level. In addition, we established an R package named Yeskit to import, integrate, analyze, and interpret pathogen abundance and transcriptomic features in host cells. Robustness of these tools has been tested on various real and simulated scRNA-seq datasets. PathogenTrack is competitive to the state-of-the-art tools such as Viral-Track, and the first tools for identifying bacteria at the single-cell level. Using the raw data of bronchoalveolar lavage fluid samples (BALF) from COVID-19 patients in the SRA database, we found the SARS-CoV-2 virus exists in multiple cell types including epithelial cells and macrophages. SARS-CoV-2-positive neutrophils showed increased expression of genes related to type I interferon pathway and antigen presenting module. Additionally, we observed the Haemophilus parahaemolyticus in some macrophage and epithelial cells, indicating a co-infection of the bacterium in some severe cases of COVID-19. The PathogenTrack pipeline and the Yeskit package are publicly available at GitHub.
COVID-19
;
Humans
;
RNA
;
SARS-CoV-2/genetics*
;
Single-Cell Analysis/methods*
;
Transcriptome
6.Integrated analysis of gut microbiome and host immune responses in COVID-19.
Xiaoguang XU ; Wei ZHANG ; Mingquan GUO ; Chenlu XIAO ; Ziyu FU ; Shuting YU ; Lu JIANG ; Shengyue WANG ; Yun LING ; Feng LIU ; Yun TAN ; Saijuan CHEN
Frontiers of Medicine 2022;16(2):263-275
Emerging evidence indicates that the gut microbiome contributes to the host immune response to infectious diseases. Here, to explore the role of the gut microbiome in the host immune responses in COVID-19, we conducted shotgun metagenomic sequencing and immune profiling of 14 severe/critical and 24 mild/moderate COVID-19 cases as well as 31 healthy control samples. We found that the diversity of the gut microbiome was reduced in severe/critical COVID-19 cases compared to mild/moderate ones. We identified the abundance of some gut microbes altered post-SARS-CoV-2 infection and related to disease severity, such as Enterococcus faecium, Coprococcus comes, Roseburia intestinalis, Akkermansia muciniphila, Bacteroides cellulosilyticus and Blautia obeum. We further analyzed the correlation between the abundance of gut microbes and host responses, and obtained a correlation map between clinical features of COVID-19 and 16 severity-related gut microbe, including Coprococcus comes that was positively correlated with CD3+/CD4+/CD8+ lymphocyte counts. In addition, an integrative analysis of gut microbiome and the transcriptome of peripheral blood mononuclear cells (PBMCs) showed that genes related to viral transcription and apoptosis were up-regulated in Coprococcus comes low samples. Moreover, a number of metabolic pathways in gut microbes were also found to be differentially enriched in severe/critical or mild/moderate COVID-19 cases, including the superpathways of polyamine biosynthesis II and sulfur oxidation that were suppressed in severe/critical COVID-19. Together, our study highlighted a potential regulatory role of severity related gut microbes in the immune response of host.
COVID-19
;
Clostridiales
;
Gastrointestinal Microbiome
;
Humans
;
Immunity
;
Leukocytes, Mononuclear
;
SARS-CoV-2
7.Emerging molecular subtypes and therapeutic targets in B-cell precursor acute lymphoblastic leukemia.
Jianfeng LI ; Yuting DAI ; Liang WU ; Ming ZHANG ; Wen OUYANG ; Jinyan HUANG ; Saijuan CHEN
Frontiers of Medicine 2021;15(3):347-371
B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is characterized by genetic alterations with high heterogeneity. Precise subtypes with distinct genomic and/or gene expression patterns have been recently revealed using high-throughput sequencing technology. Most of these profiles are associated with recurrent non-overlapping rearrangements or hotspot point mutations that are analogous to the established subtypes, such as DUX4 rearrangements, MEF2D rearrangements, ZNF384/ZNF362 rearrangements, NUTM1 rearrangements, BCL2/MYC and/or BCL6 rearrangements, ETV6-RUNX1-like gene expression, PAX5alt (diverse PAX5 alterations, including rearrangements, intragenic amplifications, or mutations), and hotspot mutations PAX5 (p.Pro80Arg) with biallelic PAX5 alterations, IKZF1 (p.Asn159Tyr), and ZEB2 (p.His1038Arg). These molecular subtypes could be classified by gene expression patterns with RNA-seq technology. Refined molecular classification greatly improved the treatment strategy. Multiagent therapy regimens, including target inhibitors (e.g., imatinib), immunomodulators, monoclonal antibodies, and chimeric antigen receptor T-cell (CAR-T) therapy, are transforming the clinical practice from chemotherapy drugs to personalized medicine in the field of risk-directed disease management. We provide an update on our knowledge of emerging molecular subtypes and therapeutic targets in BCP-ALL.
B-Lymphocytes
;
Humans
;
Mutation
;
Oncogene Proteins, Fusion/genetics*
;
Precursor B-Cell Lymphoblastic Leukemia-Lymphoma
;
Precursor Cell Lymphoblastic Leukemia-Lymphoma
8.Clinical significance of CD34
Xueping LI ; Yuting DAI ; Bing CHEN ; Jinyan HUANG ; Saijuan CHEN ; Lu JIANG
Frontiers of Medicine 2021;15(4):608-620
t(8;21)(q22;q22) acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy with a high relapse rate in China. Two leukemic myeloblast populations (CD34
Gene Expression
;
Granulocyte Precursor Cells
;
Humans
;
Immunophenotyping
;
Leukemia, Myeloid, Acute/genetics*
;
Membrane Glycoproteins
;
Prognosis
;
Proteins
;
Proto-Oncogene Proteins c-kit/genetics*
9.CAR T-cell immunotherapy: a powerful weapon for fighting hematological B-cell malignancies.
Jian-Qing MI ; Jie XU ; Jianfeng ZHOU ; Weili ZHAO ; Zhu CHEN ; J Joseph MELENHORST ; Saijuan CHEN
Frontiers of Medicine 2021;15(6):783-804
The current standard of care in hematological malignancies has brought considerable clinical benefits to patients. However, important bottlenecks still limit optimal achievements following a current medical practice. The genetic complexity of the diseases and the heterogeneity of tumor clones cause difficulty in ensuring long-term efficacy of conventional treatments for most hematological disorders. Consequently, new treatment strategies are necessary to improve clinical outcomes. Chimeric antigen receptor T-cell (CAR T) immunotherapy opens a new path for targeted therapy of hematological malignancies. In this review, through a representative case study, we summarize the current experience of CAR T-cell therapy, the management of common side effects, the causative mechanisms of therapy resistance, and new strategies to improve the efficacy of CAR T-cell therapy.
Hematologic Neoplasms/therapy*
;
Humans
;
Immunotherapy/adverse effects*
;
Neoplasms
;
Receptors, Chimeric Antigen
;
T-Lymphocytes
10.Durability of neutralizing antibodies and T-cell response post SARS-CoV-2 infection.
Yun TAN ; Feng LIU ; Xiaoguang XU ; Yun LING ; Weijin HUANG ; Zhaoqin ZHU ; Mingquan GUO ; Yixiao LIN ; Ziyu FU ; Dongguo LIANG ; Tengfei ZHANG ; Jian FAN ; Miao XU ; Hongzhou LU ; Saijuan CHEN
Frontiers of Medicine 2020;14(6):746-751
The ongoing pandemic of Coronavirus disease 19 (COVID-19) is caused by a newly discovered β Coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). How long the adaptive immunity triggered by SARS-CoV-2 can last is of critical clinical relevance in assessing the probability of second infection and efficacy of vaccination. Here we examined, using ELISA, the IgG antibodies in serum specimens collected from 17 COVID-19 patients at 6-7 months after diagnosis and the results were compared to those from cases investigated 2 weeks to 2 months post-infection. All samples were positive for IgGs against the S- and N-proteins of SARS-CoV-2. Notably, 14 samples available at 6-7 months post-infection all showed significant neutralizing activities in a pseudovirus assay, with no difference in blocking the cell-entry of the 614D and 614G variants of SARS-CoV-2. Furthermore, in 10 blood samples from cases at 6-7 months post-infection used for memory T-cell tests, we found that interferon γ-producing CD4
Adaptive Immunity/physiology*
;
Adult
;
Aged
;
Antibodies, Neutralizing/blood*
;
COVID-19/immunology*
;
Cohort Studies
;
Female
;
Humans
;
Immunoglobulin G/blood*
;
Male
;
Middle Aged
;
SARS-CoV-2/immunology*
;
T-Lymphocytes/physiology*
;
Time Factors
;
Viral Proteins/immunology*

Result Analysis
Print
Save
E-mail