Maternal HIV status skews transcriptomic response in infant cord blood monocytes exposed to Bacillus Calmette--Guerín

Single-cell immunophenotyping of the fetal immune response to maternal SARS-CoV-2 infection in late gestation

BACKGROUND

During the COVID-19 pandemic, thousands of pregnant women have been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The implications of maternal SARS-CoV-2 infection on fetal and childhood well-being need to be characterized. We aimed to characterize the fetal immune response to maternal SARS-CoV-2 infection.

METHODS

We performed single-cell RNA-sequencing and T cell receptor sequencing on cord blood mononuclear cells (CBMCs) from newborns of mothers infected with SARS-CoV-2 in the third trimester (cases) or without SARS-CoV-2 infection (controls).

RESULTS

We identified widespread gene expression changes in CBMCs from cases, including upregulation of interferon-stimulated genes and major histocompatibility complex genes in CD14⁺ monocytes, transcriptional changes suggestive of activation of plasmacytoid dendritic cells, and activation and exhaustion of natural killer cells. Lastly, we observed fetal T cell clonal expansion in cases compared to controls.

CONCLUSIONS

As none of the infants were infected with SARS-CoV-2, our results suggest that maternal SARS-CoV-2 infection might modulate the fetal immune system in the absence of vertical transmission.

IMPACT

The implications of maternal SARS-CoV-2 infection in the absence of vertical transmission on fetal and childhood well-being are poorly understood. Maternal SARS-CoV-2 infection might modulate the fetal immune system in the absence of vertical transmission. This study raises important questions about the untoward effects of maternal SARS-CoV-2 on the fetus, even in the absence of vertical transmission.

The landscape of different molecular modules in an immune microenvironment during tuberculosis infection

Tuberculosis is a chronic inflammatory disease caused by Mycobacterium tuberculosis. When tuberculosis invades the human body, innate immunity is the first line of defense. However, how the innate immune microenvironment responds remains unclear. In this research, we studied the function of each type of cell and explained the principle of an immune microenvironment. Based on the differences in the innate immune microenvironment, we modularized the analysis of the response of five immune cells and two structural cells. The results showed that in the innate immune stress response, the genes CXCL3, PTGS2 and TNFAIP6 regulated by the nuclear factor kappa B(NK-KB) pathway played a crucial role in fighting against tuberculosis. Based on the active pathway algorithm, each immune cell showed metabolic heterogeneity. Besides, after tuberculosis infection, structural cells showed a chemotactic immunity effect based on the co-expression immunoregulatory module.