COVID-19に伴う自然免疫系への長期的影響(Long-term effects on the innate immune system following COVID-19)


COVID-19感染症が重症化するほど、免疫系の活性化に必要な樹状細胞などの免疫細胞の回復が遅くなることが分かっています。LiUの研究者が研究で示した。COVID-19の重症化から6ヵ月後でも、数種類の免疫細胞に悪影響が見られる。 The more severe the COVID-19 infection, the slower the recovery of immune cells, such as the dendritic cells, which are necessary for the activation of the immune system. This is shown by researchers at LiU in a new study. Six months after severe COVID-19, a negative impact on several types of immune cells can still be seen.

2023-01-19 スウェーデン・リンショーピング大学



COVID-19の入院後6ヶ月以上持続する単球および樹状細胞サブセットの大きな変化 Major alterations to monocyte and dendritic cell subsets lasting more than 6 months after hospitalization for COVID-19

Francis R. Hopkins, Melissa Govender, Cecilia Svanberg, Johan Nordgren, Hjalmar Waller, Åsa Nilsdotter-Augustinsson, Anna J. Henningsson, Marie Hagbom, Johanna Sjöwall, Sofia Nyström and Marie Larsson
Frontiers in Immunology  Published:04 January 2023

Introduction: After more than two years the Coronavirus disease-19 (COVID-19) pandemic continues to burden healthcare systems and economies worldwide, and it is evident that the effects on the immune system can persist for months post-infection. The activity of myeloid cells such as monocytes and dendritic cells (DC) is essential for correct mobilization of the innate and adaptive responses to a pathogen. Impaired levels and responses of monocytes and DC to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is likely to be a driving force behind the immune dysregulation that characterizes severe COVID-19.

Methods: Here, we followed a cohort of COVID-19 patients hospitalized during the early waves of the pandemic for 6-7 months. The levels and phenotypes of circulating monocyte and DC subsets were assessed to determine both the early and long-term effects of the SARS-CoV-2 infection.

Results: We found increased monocyte levels that persisted for 6-7 months, mostly attributed to elevated levels of classical monocytes. Myeloid derived suppressor cells were also elevated over this period. While most DC subsets recovered from an initial decrease, we found elevated levels of cDC2/cDC3 at the 6-7 month timepoint. Analysis of functional markers on monocytes and DC revealed sustained reduction in program death ligand 1 (PD-L1) expression but increased CD86 expression across almost all cell types examined. Finally, C-reactive protein (CRP) correlated positively to the levels of intermediate monocytes and negatively to the recovery of DC subsets.

Conclusion: By exploring the myeloid compartments, we show here that alterations in the immune landscape remain more than 6 months after severe COVID-19, which could be indicative of ongoing healing and/or persistence of viral antigens.