ABSTRACT
Pregnancy is a complex phenomenon during which women undergo immense immunological change throughout this period. Having an infection with the SARS-CoV-2 virus leads to an additional burden on the highly stretched immune response. Some studies suggest that age-matched pregnant women are more prone to SARS-CoV-2 infection compared with normal healthy (non-pregnant) women, while alternative evidence proposed that pregnant women are neither susceptible nor develop severe symptoms. This discrepancy in different findings regarding the immune responses of pregnant women infected with SARS-CoV-2 virus is not well understood. In this study, we investigated how SARS-CoV-2 viral infection could modulate the immune landscape during the active infection phase and recovery in pregnant females. Using flow cytometry, we identified that intermediate effector CD8+ T cells were increased in pregnant women who had recovered from COVID-19 as opposed to those currently infected. Similarly, an increase in CD4+ T helper cells (early or late) during the recovered phase was observed during the recovery phase compared with infected pregnant women or healthy pregnant women, whilst infected pregnant women had a reduced number of late effector CD4+ T cells. CD3+CD4- CD8-NKT cells that diminished during active infection in contrast to healthy pregnant women were significant increase in recovered COVID-19 recovered pregnant women. Further, our single-cell RNA sequencing data revealed that infection of SARS-CoV-2 had changed the gene expression profile of monocytes, CD4+ effector cells and antibody producing B cells in convalescent as opposed to healthy pregnant women. Additionally, several genes with cytotoxic function, interferon signalling type I & II, and pro- and anti-inflammatory functions in natural killer cells and CD8+ cytotoxic T cells were compromised in recovered patients compared with healthy pregnant women. Overall, our study highlights that SARS-CoV-2 infection deranged the adaptive immune response in pregnant women and could be implicated in pregnancy complications in ongoing pregnancies.
ABSTRACT
PURPOSE: Disseminated tumor cells (DTCs) from bone marrow (BM) are a surrogate of minimal residual disease (MRD) in primary breast cancer (PBC) patients and associated with an adverse prognosis. However, BM sampling is an invasive procedure. Although there is growing evidence that circulating tumor cells (CTCs) from the blood are also suitable for monitoring MRD, data on the simultaneous detection of DTCs and CTCs are limited. MATERIALS AND METHODS: We determined the presence of DTCs using immunocytochemistry and the pan-cytokeratin antibody A45-B/B3. CTCs were determined simultaneously using a reverse transcription-polymerase chain reaction-based assay (AdnaTest Breast Cancer) and CellSearch (at least one CTC per 7.5 mL blood). We compared the detection of DTCs and CTCs and evaluated their impact on disease-free and overall survival. RESULTS: Of 585 patients, 131 (22%) were positive for DTCs; 19 of 202 (9%) and 18 of 383 (5%) patients were positive for CTCs, as shown by AdnaTest and CellSearch, respectively. No significant association was observed between DTCs and CTCs (p=0.248 and p=0.146 as shown by AdnaTest and CellSearch, respectively). The presence of DTCs (p=0.046) and the presence of CTCs as shown by CellSearch (p=0.007) were predictive of disease-free survival. CONCLUSION: Our data confirm the prognostic relevance of DTCs and CTCs in patients with PBC. As we found no significant relationship between DTCs and CTCs, prospective trials should include their simultaneous detection. Within those trials, the question of whether or not DTCs and CTCs are independent subpopulations of malignant cell clones should be determined by molecular characterization.
