Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SAR...Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SARS-CoV-2,which is the virus causing coronavirus disease 2019(COVID-19),uses the angiotensin-converting enzyme 2(ACE2)as a cell receptor to invade human cells.Thus,ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection.This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.Methods:We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger(ages≤49 years)and older(ages>49 years)persons using two-sided Student's t test.We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.Results:ACE2 expression levels were the highest in the small intestine,testis,kidneys,heart,thyroid,and adipose tissue,and were the lowest in the blood,spleen,bone marrow,brain,blood vessels,and muscle.ACE2 showed medium expression levels in the lungs,colon,liver,bladder,and adrenal gland.ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue.In the skin,digestive system,brain,and blood vessels,ACE2 expression levels were positively associated with immune signatures in both males and females.In the thyroid and lungs,ACE2 expression levels were positively and negatively associated with immune signatures in males and females,respectively,and in the lungs they had a positive and a negative correlation in the older and younger groups,respectively.Conclusions:Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes,ages,and races equally.The different host immune responses to SARS-CoV-2 infection may partially explain why males and females,young and old persons infected with this vi展开更多
Since the first case of novel H7N9 infection was reported,China has experienced five epidemics of H7N9.During the fifth wave,a highly pathogenic H7N9 strain emerged.Meanwhile,the H7N9 virus continues to accumulate mut...Since the first case of novel H7N9 infection was reported,China has experienced five epidemics of H7N9.During the fifth wave,a highly pathogenic H7N9 strain emerged.Meanwhile,the H7N9 virus continues to accumulate mutations,and its affinity for the human respiratory epithelial sialic acid 2-6 receptor has increased.Therefore,a pandemic is still possible.In the past 6 years,we have accumulated rich experience in dealing with H7N9,especially in terms of virus tracing,epidemiological research,key site mutation monitoring,critical disease mechanisms,clinical treatment,and vaccine development.In the research fields above,significant progress has been made to effectively control the spread of the epidemic and reduce the fatality rate.To fully document the research progress concerning H7N9,we reviewed the clinical and epidemiological characteristics of H7N9,the key gene mutations of the virus,and H7N9 vaccine,thus providing a scientific basis for further monitoring and prevention of H7N9 influenza epidemics.展开更多
Pandemic influenza has posed an increasing threat to public health worldwide in the last decade.In the 20th century,three human pandemic influenza outbreaks occurred in 1918,1957 and 1968,causing significant mortality...Pandemic influenza has posed an increasing threat to public health worldwide in the last decade.In the 20th century,three human pandemic influenza outbreaks occurred in 1918,1957 and 1968,causing significant mortality.A number of hypotheses have been proposed for the emergence and development of pandemic viruses,including direct introduction into humans from an avian origin and reassortment between avian and previously circulating human viruses,either directly in humans or via an intermediate mammalian host.However,the evolutionary history of the pandemic viruses has been controversial,largely due to the lack of background genetic information and rigorous phylogenetic analyses.The pandemic that emerged in early April 2009 in North America provides a unique opportunity to investigate its emergence and development both in human and animal aspects.Recent genetic analyses of data accumulated through long-term influenza surveillance provided insights into the emergence of this novel pandemic virus.In this review,we summarise the recent literature that describes the evolutionary pathway of the pandemic viruses.We also discuss the implications of these findings on the early detection and control of future pandemics.展开更多
基金This work was supported by the China Pharmaceutical University(grant number 3150120001 to XW)。
文摘Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SARS-CoV-2,which is the virus causing coronavirus disease 2019(COVID-19),uses the angiotensin-converting enzyme 2(ACE2)as a cell receptor to invade human cells.Thus,ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection.This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.Methods:We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger(ages≤49 years)and older(ages>49 years)persons using two-sided Student's t test.We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.Results:ACE2 expression levels were the highest in the small intestine,testis,kidneys,heart,thyroid,and adipose tissue,and were the lowest in the blood,spleen,bone marrow,brain,blood vessels,and muscle.ACE2 showed medium expression levels in the lungs,colon,liver,bladder,and adrenal gland.ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue.In the skin,digestive system,brain,and blood vessels,ACE2 expression levels were positively associated with immune signatures in both males and females.In the thyroid and lungs,ACE2 expression levels were positively and negatively associated with immune signatures in males and females,respectively,and in the lungs they had a positive and a negative correlation in the older and younger groups,respectively.Conclusions:Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes,ages,and races equally.The different host immune responses to SARS-CoV-2 infection may partially explain why males and females,young and old persons infected with this vi
基金supported by the State Project of Essential Drug Research and Development(No.2015ZX09101044).
文摘Since the first case of novel H7N9 infection was reported,China has experienced five epidemics of H7N9.During the fifth wave,a highly pathogenic H7N9 strain emerged.Meanwhile,the H7N9 virus continues to accumulate mutations,and its affinity for the human respiratory epithelial sialic acid 2-6 receptor has increased.Therefore,a pandemic is still possible.In the past 6 years,we have accumulated rich experience in dealing with H7N9,especially in terms of virus tracing,epidemiological research,key site mutation monitoring,critical disease mechanisms,clinical treatment,and vaccine development.In the research fields above,significant progress has been made to effectively control the spread of the epidemic and reduce the fatality rate.To fully document the research progress concerning H7N9,we reviewed the clinical and epidemiological characteristics of H7N9,the key gene mutations of the virus,and H7N9 vaccine,thus providing a scientific basis for further monitoring and prevention of H7N9 influenza epidemics.
基金This study was supported by Li Ka Shing Foundation,the Area of Excellence Scheme of the University Grants Committee of the Hong Kong Special Administrative Region Government(grant AoE/M-12/06)the National Institutes of Health(NIH,National Institute of Allergy and Infectious Diseases contract HSN266200700005C).
文摘Pandemic influenza has posed an increasing threat to public health worldwide in the last decade.In the 20th century,three human pandemic influenza outbreaks occurred in 1918,1957 and 1968,causing significant mortality.A number of hypotheses have been proposed for the emergence and development of pandemic viruses,including direct introduction into humans from an avian origin and reassortment between avian and previously circulating human viruses,either directly in humans or via an intermediate mammalian host.However,the evolutionary history of the pandemic viruses has been controversial,largely due to the lack of background genetic information and rigorous phylogenetic analyses.The pandemic that emerged in early April 2009 in North America provides a unique opportunity to investigate its emergence and development both in human and animal aspects.Recent genetic analyses of data accumulated through long-term influenza surveillance provided insights into the emergence of this novel pandemic virus.In this review,we summarise the recent literature that describes the evolutionary pathway of the pandemic viruses.We also discuss the implications of these findings on the early detection and control of future pandemics.
