Exploring myometrial microenvironment changes at the single-cell level from nonpregnant to term pregnant states

Abstract

The microenvironment and cell populations within the myometrium play crucial roles in maintaining uterine structural integrity and protecting the fetus during pregnancy. However, the specific changes occurring at the single-cell level in the human myometrium between non-pregnant (NP) and term pregnant (TP) states remain unexplored. In this study, we utilized single-cell RNA sequence (scRNA-seq) and spatial transcriptomics (ST) to construct a transcriptomic atlas of individual cells in the myometrium of NP and TP women. Integrated analysis of scRNA-seq and ST data revealed spatially distinct transcriptional characteristics and examined cell-to-cell communication patterns based on ligand-receptor interactions. We identified and categorized 87,845 high-quality individual cells into twelve populations from scRNA-seq data of 12 human myometrium tissues. Our findings demonstrated alterations in the proportions of four sub-populations of smooth muscle cells (SMCs) in TP. Moreover, an increase in monocytic cells, particularly M2 macrophages, was observed in TP myometrium samples, suggesting their involvement in the anti-inflammatory response. This study provides unprecedented single-cell resolution of NP and TP myometrium, offering new insights into myometrial remodeling during pregnancy.

Single-cell and spatial transcriptomics reveal alterations in trophoblasts at invasion sites and disturbed myometrial immune microenvironment in placenta accreta spectrum disorders

“…In the placenta group, one sample was used for ST and two samples for scRNA-seq. Additionally, normal myometrium samples were obtained from three term non-labor women (myometrium group: ST, n = 1; scRNA-seq, n = 2), these samples were also used in our previous publications [ 35 , 36 ]. The sample collection procedure adhered to the previously described protocol [ 35 , 36 ].…”

“…Additionally, normal myometrium samples were obtained from three term non-labor women (myometrium group: ST, n = 1; scRNA-seq, n = 2), these samples were also used in our previous publications [ 35 , 36 ]. The sample collection procedure adhered to the previously described protocol [ 35 , 36 ]. The clinical information for the PAS samples was described in Table S1.…”

“…These sections were mounted on highly adhesive slides for sample selection, and confirmed for optimal positioning through H&E staining. Subsequently, the tissues sections were fixed onto 10X Visium Tissue Optimization Slides or Visium Spatial Gene Expression Slides (10X Genomics), followed by cell lysis and library preparation for sequencing as previously described [ 35 , 36 ]. The integrity and quality of the library DNA fragments were evaluated using an Agilent 2100 instrument.…”