Autoimmune diseases represent a severe personal and healthcare problem that seeks novel therapeutic solutions. Mesenchymal stem cells (MSCs) are multipotent cells with interesting cell biology and promising therapeutic potential. The immunoregulatory effects of secretory factors produced by umbilical cord mesenchymal stem cells (UC-MSCs) were assessed on B lymphocytes from 17 patients with systemic lupus erythematosus (SLE), as defined by the 2019 European Alliance of Associations for Rheumatology (EULAR)/American College of Rheumatology (ACR) classification criteria for SLE, and 10 healthy volunteers (HVs). Peripheral blood mononuclear cells (PBMCs) from patients and HVs were cultured in a UC-MSC-conditioned medium (UC-MSCcm) and a control medium. Flow cytometry was used to detect the surface expression of CD80, CD86, BR3, CD40, PD-1, and HLA-DR on CD19+ B cells and assess the percentage of B cells in early and late apoptosis. An enzyme-linked immunosorbent assay (ELISA) quantified the production of BAFF, IDO, and PGE2 in PBMCs and UC-MSCs. Under UC-MSCcm influence, the percentage and mean fluorescence intensity (MFI) of CD19+BR3+ cells were reduced in both SLE patients and HVs. Regarding the effects of the MSC secretome on B cells in lupus patients, we observed a decrease in CD40 MFI and a reduced percentage of CD19+PD-1+ and CD19+HLA-DR+ cells. In contrast, in the B cells of healthy participants, we found an increased percentage of CD19+CD80+ cells and decreased CD80 MFI, along with a decrease in CD40 MFI and the percentage of CD19+PD-1+ cells. The UC-MSCcm had a minimal effect on B-cell apoptosis. The incubation of patients’ PBMCs with the UC-MSCcm increased PGE2 levels compared to the control medium. This study provides new insights into the impact of the MSC secretome on the key molecules involved in B-cell activation and antigen presentation and survival, potentially guiding the development of future SLE treatments.

Polycystic ovary syndrome (PCOS) represents a common and complex endocrine condition that impacts women at all stages of reproductive development. As 2025 marks the 90th anniversary of its first clinical description by Stein and Leventhal, this review revisits the syndrome through the metaphor of an iceberg: while hyperandrogenism, anovulation, and polycystic ovarian morphology comprise the visible «tip,» a substantial portion of the burden lies beneath the surface. The clinical criteria, while necessary for diagnosis, often overshadow the deeper systemic and psychosocial complexities of PCOS. Beneath these surface manifestations exist significant metabolic disturbances - including insulin resistance, dyslipidemia, and increased cardiometabolic risk - as well as psychological burdens such as depression, anxiety, and impaired quality of life. These dimensions remain insufficiently recognized, leading to delayed diagnosis, fragmented care, and significant unmet patient needs. The persistent underestimation of the syndrome’s breadth reflects a broader disconnect between clinical awareness and the actual experience of patients in the real world. This article explores the historical trajectory of PCOS diagnosis, unpacks the full spectrum of its concealed comorbidities, and highlights the critical importance of a multidimensional, individualized, and holistic clinical strategy. Recognizing the hidden burden of PCOS is not merely a matter of improved diagnostics - it is a call for a paradigm shift toward compassionate, interdisciplinary, and lifelong care.