Critical Analysis of Dendritic Cell Function and HSD11B1 Expression in Endometriosis: A Study with Methodological Concerns

The article authored by Xu Yang, et al. provides a comprehensive analysis of two aspects of the study. Firstly, it examines the levels and functions of dendritic cells (DCs) in three different tissues of patients with endometriosis. Secondly, it investigates the high expression of the HSD11B1 gene in endometriotic lesions and DCs, and its potential role in the disease. The authors report a decrease in the number of DCs, reduced cell viability, increased apoptosis, and elevated levels of inflammatory factors in endometriotic lesions. They also discovered high expression of HSD11B1 in endometriotic lesions and DCs, indicating its involvement in inhibiting DC maturation and contributing to the development of endometriosis. However, the study lacks coherence between these two parts, and the evidence provided is not robust. The authors' conclusions are overstated, and the article lacks originality.

The following are the major concerns:

1. The authors highlight the issue of DC maturation in the title, but in Figure 1, they did not differentiate between mature and immature DCs in the flow cytometry results.

2. In Figure 2, the authors cultured DC cells in vitro for 5 days to investigate their functions. It is unclear why they chose this specific duration and what treatments were administered during this period. Additionally, it is not clear why functional assays were not performed immediately after cell isolation. Were IL-12, TNF-α, and IL-6 also measured after 5 days of culture?

3. If endometriotic lesion DC cells exhibit higher apoptosis and lower proliferative activity, it is contradictory that the levels of IL-12, TNF-α, and IL-6, which reflect DC cell activity, increased instead.

4. Without fully elucidating the distribution and functional status of different DC subsets in endometriosis, it is difficult to understand why the authors focused on studying the expression and function of the HSD11B1 gene in stromal cells and DC cells.

5. The results presented in Figure 3 do not provide conclusive evidence of the expression of HSD11B1 in endometriotic lesions. It is advisable to conduct immunohistochemistry (IHC) on endometriotic lesions, followed by primary culture of ESCs and subsequent analysis using PCR and protein Western blotting to confirm the expression of HSD11B1.

6. Without clarifying the expression of HSD11B1 in ESCs, it is unclear why the authors overexpressed HSD11B1 in ESCs and its impact on DC function. It is possible that HSD11B1 is expressed in the endometrial epithelial cells in endometriotic lesions.

7. The authors exaggerate their research findings in Figure 5G. Based on the available data, it is challenging to accept their emphasis on the role of HSD11B1 in regulating DC differentiation in ESC and iDC cells.

8. The title of the article is confusing and lacks clarity in conveying its intended message.

In addition to these major concerns, there are also minor concerns:

1. The authors fail to provide a description of biological replicates for the samples in several instances in the figures, which raises doubts about the statistical analysis of the presented data.

2. The article lacks clarity in describing the experimental methods and presenting the data results in several instances.