Characteristics and origin of the immunocyte that causes lung damage under COVID-19 infection discovered
Important data that explains the duality of macrophage reacting to viral infections
(From left) Lee Ki-jong Ko Jun-young doctoral students Professor Park Su-hyung Doctor Lee Jung-seok of GENOMEinSIGHT [Photo provided = KAIST]
4th of this month the research team lead by Professor Park Su-hyung of KAIST Graduate School of Medical Science and Engineering announced that under co-research with Professor Choi Young-ki of Chungbuk National University College of Medicine and Doctor Lee Jung-seok of GENOMEinSIGHT and their team they discovered the characteristic and origin of a specific immunocyte that causes lung damage under COVID-19 infection by investigating the quantitative and qualitative changes of immune reactions occurred during the peak and recovery period. It suggests a target that may control the lung damage caused by overreaction of immune system of COVID-19 patients.
It is well known that immunocytes of lungs immediately respond to the COVID-19. Most of them are macrophage which are diversions of monocytes that removes infected lung tissue cells.
The gradual change of immune reaction and immunocytes cannot be researched on patients. Instead ferrets are used. Research team lead by Professor Choi Young-ki of Chungbuk National University was the first to report that ferrets are receptive to SARS-CoV-2 virus.
The research team utilized single cell sequencing to precisely analyze the change of lung immunocytes of infected animal models and classified macrophage into 10 subtypes and discovered which of them contributes to lung damage.
The team observed quantitative increase of macrophage in the second day of COVID-19 infection. Macrophage created in this process strongly appears characteristics of inflammatory macrophage showing possibilities of both viral extermination and tissue damage. This division of monocyte is similar to the status of lungs of serious COVID-19 patients.
The research was supported by the Ministry of Health of Welfare and KAIST. The result of was published in Nature communications in 28th of July on the name of ‘Single-cell transcriptome of bronchoalveolar lavage fluid reveals sequential change of macrophages during SARS-CoV-2 infection in ferrets’.
The team conducted trace tracking to COVID-19 patients injected with immunosuppressant to control= fatal overreaction under COVID-19 such as hypercytokinemia and investigate epidemiological effects of medicines.
Lee and Ko said that the research analyzed the immune reaction through single tissue transcriptome which enhances understanding of duality of macrophage immune reaction.
Choi said that the research would increase understandings about general pathogenesis that is related to viral infection and cure by conducting viral proliferation and pathological analysis in COVID-19 infection.
Park said that the research investigated the status of lung before and after COVID-19 infection discovering that the damage is caused by macrophage and it may refine immunosuppressive cure strategy.