OBJECTIVE: To review the research progress of three-dimensional (3D) bioprinting technology for wound dressing design and preparation. METHODS: The literature on 3D bioprinted wound dressings in recent years, both domestically and internationally, was retrieved. The core principles of 3D bioprinting technology, mainstream methods, and their applications in wound dressings design and preparation were summarized. RESULTS: By leveraging precise spatial manipulation capabilities and multi-material integration, 3D bioprinting technology constructs the functionalized wound dressings with complex structures and bioactivity. These dressings primarily function across several dimensions: wound hemostasis, infection control, controlled drug release, and monitoring wound healing. CONCLUSION Although 3D bioprinted wound dressings can promote wound healing through multiple dimensions, large-scale clinical validation is still lacking. Future efforts should further clarify their clinical value and scope of application to provide more efficient, precise, and patient-comfortable treatment options for refractory wounds .
Humans ; Wound Healing ; Printing, Three-Dimensional ; Bioprinting/methods* ; Bandages ; Tissue Engineering/methods* ; Tissue Scaffolds ; Biocompatible Materials

OBJECTIVE: To summarize recent research progress in hydrogel-based growth factors for treatment of intervertebral disc degeneration (IDD). METHODS: The relevant literature on hydrogel-based growth factors for IDD treatment at home and abroad was extensively reviewed, and their advantages and therapeutic effects in repairing IDD were analyzed and summarized. RESULTS: Hydrogels exhibit high hydration, biocompatibility, and biodegradability, enabling targeted delivery and sustained release of growth factors such as growth differentiation factors and transforming growth factors. This facilitates enhanced efficacy in promoting cell proliferation, extracellular matrix synthesis, and reducing inflammatory responses. Consequently, hydrogels demonstrate broad application prospects in the repair of IDD. CONCLUSION Research on hydrogel-based growth factors for treating IDD demonstrates advantages such as avoiding disc damage caused by repeated injections and controlling growth factor release concentrations. However, drawbacks include the limited variety of loaded growth factors and the need to verify the long-term stability and biocompatibility of hydrogels. Therefore, further research is required on aspects such as the types of loaded growth factors and the long-term stability and biocompatibility of hydrogels to establish an experimental foundation for their clinical application.
Intervertebral Disc Degeneration/therapy* ; Hydrogels/chemistry* ; Humans ; Intercellular Signaling Peptides and Proteins/administration & dosage* ; Biocompatible Materials/chemistry* ; Animals ; Tissue Engineering/methods* ; Cell Proliferation/drug effects* ; Drug Delivery Systems

OBJECTIVE: To summarize the biomechanical research progress of biomaterials in rotator cuff injury repair and to explore how biomaterials can restore the native histological and mechanical properties of the rotator cuff. METHODS: The relevant literature at home and abroad was widely reviewed to analyze the biomechanical properties of synthetic biomaterials, naturally derived biomaterials, and tissue grafts in the repair of rotator cuff injuries. RESULTS: Synthetic biomaterials [such as poly (lactic-co-glycolic acid) and polycaprolactone] can provide initial stable mechanical support due to their adjustable mechanical properties and degradation characteristics, while naturally derived biomaterials (such as collagen and hyaluronic acid) can promote cell adhesion and tissue integration due to their biocompatibility and bioactivity. Tissue grafts exhibit significant clinical utility by providing immediate mechanical stability and promoting tendon-to-bone healing. Three-dimensional bioprinting technology provides new possibilities for personalized repair of rotator cuff injuries by precisely controlling the spatial distribution and mechanical properties of biomaterials. CONCLUSION Future studies should further optimize the design of bioprinting materials, cell sources, and scaffolds to achieve better mechanical properties and clinical efficacy of biomaterials in the repair of rotator cuff injuries.
Humans ; Rotator Cuff Injuries ; Biocompatible Materials/chemistry* ; Biomechanical Phenomena ; Tissue Scaffolds ; Rotator Cuff/surgery* ; Tissue Engineering/methods* ; Polyesters ; Polyglycolic Acid/chemistry* ; Hyaluronic Acid/chemistry* ; Collagen/chemistry* ; Lactic Acid/chemistry* ; Polylactic Acid-Polyglycolic Acid Copolymer ; Bioprinting ; Wound Healing ; Printing, Three-Dimensional ; Tendon Injuries/surgery*

Objective To investigate the effects of hyaluronic acid and proteoglycan-linked protein 1 (HAPLN1) secreted by synovial fibroblasts (FLS) on the polarization of macrophages (Mϕ) in rheumatoid arthritis (RA). Methods Human monocytic leukemia cells (THP-1) were differentiated into Mϕ, which were subsequently exposed to recombinant HAPLN1 (rHAPLN1). RA-FLS were transfected separately with HAPLN1 overexpression plasmid (HAPLN1^OE) or small interfering RNA targeting HAPLN1 (si-HAPLN1), and then co-cultured with Mϕ to establish a co-culture model. The viability of Mϕ was assessed using the CCK-8 assay, and the proportions of pro-inflammatory M1-type and anti-inflammatory M2-type Mϕ were analyzed by flow cytometry. Additionally, the expression levels of inflammatory markers, including interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), and inducible nitric oxide synthase (iNOS), were quantified using quantitative real-time PCR and Western blot analysis. Results The viability of Mϕ was increased in the rHAPLN1 group compared to the control group. Furthermore, both the M1/Mϕ ratio and inflammatory factor levels were elevated in the rHAPLN1 and HAPLN1^OE groups. In contrast, the si-HAPLN1 group exhibited a decrease in the M1/Mϕ ratio and inflammatory factor expression. Notably, the introduction of rHAPLN1 in rescue experiments further promoted Mϕ polarization towards the M1 phenotype. Conclusion HAPLN1, secreted by RA fibroblast-like synoviocytes (RA-FLS), enhances Mϕ polarization towards the M1 phenotype.
Humans ; Arthritis, Rheumatoid/genetics* ; Macrophages/immunology* ; Fibroblasts/metabolism* ; Phenotype ; Extracellular Matrix Proteins/genetics* ; Proteoglycans/genetics* ; Synovial Membrane/cytology* ; Tumor Necrosis Factor-alpha/genetics* ; Interleukin-1beta/genetics* ; Nitric Oxide Synthase Type II/genetics* ; Cell Differentiation ; Coculture Techniques ; THP-1 Cells

Objective To observe the effect of m⁶A methylation regulation on Notch1 pathway on the homing of BMSCs in asthma, and the intervention study of traditional Chinese medicine compound Yanghe Pingchuan Granules. Methods Rat bone mesenchymal stem cells(BMSC)and bronchial epithelial cells were cocultured. The extracted cells were divided into: bronchial epithelial cell group, asthma bronchial epithelial cell+mesenchymal stem cell co-culture group (co-culture group), co-culture cell+normal serum group, coculture cell+serum containing optimal drug group, siRNA FTO+normal serum group, siRNA FTO-NC+normal serum group, and siRNA FTO+serum containing optimal drug group. The vitality and cell cycle changes of co-cultured cells were detected. The level and markers of homing BMSC were detected by immunofluorescence staining. The expression of Notch1 pathway related genes were detected by qRT-PCR. The expression of Notch1 pathway related proteins were detected by Western blot. Results Compared with bronchial epithelial cell group, the co-cultured cell group showed an increase in the homing level of BMSCs and the expression of C-X-C motif chemokine receptor 4 (CXCR4), stromal cell-derived factor 1 (SDF-1), Notch1, transcription factor recombination signal binding protein-J (RBP-J), and hairy enhancer of split 1 (Hes1) proteins. Compared with the co-cultured cell group and co-cultured cell+normal serum group, the co-cultured cell+serum containing optimal drug group showed an increase in the homing level of BMSCs and the expressions of CXCR4 and SDF-1, while the protein and mRNA levels of Notch1 and Hes1 decreased. Compared with the siRNA FTO-NC+normal serum group, the siRNA FTO+normal serum group showed an increase in the levels of Notch1, activated Notch1, RBP-J, Hes1 protein, and cell viability, while the level of homing BMSC decreased. Compared with siRNA FTO+normal serum group, the levels of Notch1, RBP-J mRNA, activated Notch1, and Hes1 protein decreased, while the level of homing BMSCs increased in siRNA FTO+serum containing optimal drug group. The levels of Notch1, RBP-J, and Hes1 mRNA were reduced in the co-cultured cells+serum containing optimal drug group. Compared with siRNA FTO+serum containing optimal drug group, the expressions of Notch1, activated Notch1, RBP-J, Hes1 protein and cell viability decreased, while the level of homing BMSCs increased in the co-cultured cells+serum containing optimal drug group. Conclusion Yanghe Pingchuan Granules may promote the homing of BMSCs in asthma and alleviate asthma inflammation by upregulating the expression of FTO and inhibiting the expression of downstream genes in the Notch1 signaling pathway.
Animals ; Receptor, Notch1/genetics* ; Mesenchymal Stem Cells/cytology* ; Asthma/genetics* ; Drugs, Chinese Herbal/pharmacology* ; Signal Transduction/drug effects* ; Rats ; Coculture Techniques ; Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics* ; Epithelial Cells/metabolism* ; Rats, Sprague-Dawley ; Cells, Cultured ; Male

Objective To investigate the regulatory effect of tumor necrosis factor-α-induced protein-8-like factor 2 (TIPE2) on the phenotype of lung cancer tumor-associated macrophages (TAM) and its influence on the stemness of lung cancer cells. Methods Mouse macrophage cell line RAW264.7 was cultured and infected with either LV-TIPE2 lentivirus or negative control LV-NC lentivirus. The TIPE2 expression in infected cells was assessed by real-time quantitative PCR (RT-qPCR) and Western blotting to verify transfection efficiency. The infected RAW264.7 cells were co-cultured with lung cancer cell line A549, and were divided into four groups: control group (RAW264.7 cells or A549 cells cultured alone), TAM group (RAW264.7 cells co-cultured with A549 cells), LV-NC group (RAW264.7 cells infected with LV-NC and co-cultured with A549 cells), LV-TIPE2 group (RAW264.7 cells infected with LV- TIPE2 and co-cultured with A549 cells). The RAW264.7 cells were collected after co-culture, and the expression of mannose receptor (CD206) protein of M2 macrophages was detected by cellular immunofluorescence staining. The proportions of M1 and M2 macrophages were detected by flow cytometry. After co-culture, A549 cells were collected, and their activity was assessed by CCK-8 assay. Self-renewal ability was evaluated using tumor cell pelleting experiment. The expression of stemness marker proteins-including cluster of differentiation 133 (CD133), transmembrane adhesion molecule (CD44), sex-determining region Y-box protein 2 (SOX2) and octamer-binding transcription factor 4 (OCT4)-was detected by Western blot. Results Compared with the control group or LV-NC group, the relative mRNA and protein expression levels of TIPE2 in RAW264.7 cells from the LV-TIPE2 group were significantly upregulated. Compared with the control group, the fluorescence intensity of M2-type macrophage marker CD206 protein in RAW264.7 cells from the TAM group was significantly increased, the proportion of M1-type macrophages was significantly decreased, and the proportion of M2-type macrophages was significantly increased. In contrast, compared with the TAM group, the fluorescence intensity of CD206 protein in RAW264.7 cells from the LV-TIPE2 group was significantly decreased, the proportion of M1-type macrophages was significantly increased, and the proportion of M2-type macrophages was significantly decreased. Compared with the control group, the proliferation activity of A549 cells in TAM group was significantly increased, the number of tumor pellet formation was significantly increased, and the relative expression levels of CD133, CD44, SOX2 and OCT4 were significantly up-regulated. However, compared with the TAM group, the proliferation activity of A549 cells from the LV-TIPE2 group was significantly decreased, the number of tumor pellet formation was significantly decreased, and the relative expression levels of CD133, CD44, SOX2 and OCT4 were significantly decreased. Conclusion TIPE2 can suppress the stemness of lung cancer cells by inhibiting the polarization of macrophages to M2-type, thereby exerting an anticancer effect.
Animals ; Mice ; Humans ; Tumor-Associated Macrophages/metabolism* ; Lung Neoplasms/genetics* ; Intracellular Signaling Peptides and Proteins/metabolism* ; RAW 264.7 Cells ; A549 Cells ; Phenotype ; Coculture Techniques ; Receptors, Cell Surface/metabolism* ; Neoplastic Stem Cells/metabolism* ; Mannose Receptor ; Mannose-Binding Lectins/metabolism* ; Lectins, C-Type/metabolism* ; Cell Polarity ; Macrophages/metabolism*

Objective To investigate how culture duration affects the expression of immune membrane proteins in human monocyte-derived dendritic cells (DCs) and their exosomes (DEXs). Methods Human monocytes were induced with recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) to differentiate into DCs and were subsequently matured with tumor necrosis factor α(TNF-α). Exosomes were isolated by ultracentrifugation, and DEXs were identified by transmission electron microscopy and Amnis imaging flow cytometry, which were also used to quantify the expression of immune membrane proteins on DCs and DEXs. Results On the 10th day of culture, DCs displayed high surface expression of CD11c, CD80, CD86, major histocompatibility complex class I (MHC-I), and MHC-II. Expression peaked at day 18(CD11c: 78.66%±20.33%, CD80: 76.41%±10.02%, CD86: 96.43%±0.43%, MHC-I: 84.71%±2.96%, MHC-II: 80.01%±7.03%). After day 24, the overall expression showed a declining trend, with statistically significant differences observed for all markers except CD80 and MHC-II. By day 30, 80% of the DCs still expressed CD80, CD86, and MHC-II. The expression of immune membrane proteins on DEX surfaces also reached its peak on day 18, followed by an overall decline with prolonged culture time, with statistically significant differences observed for all markers except CD80. Correlation analysis revealed a significant positive relationship between the expression levels of immune membrane proteins on DC and DEX surfaces (CD11c: r=0.98; CD80: r=0.65; CD86: r=0.82; MHC-I: r=0.86; MHC-II: r=0.93). Conclusion Human monocyte-derived DCs in vitro express high expression of immune membrane proteins and maintain stable expression over a specific period. The exosomes secreted by these cells similarly demonstrate high surface expression of immune membrane proteins, with temporal trends aligned with those of the parent DCs.
Humans ; Dendritic Cells/immunology* ; Exosomes/immunology* ; Monocytes/metabolism* ; Cells, Cultured ; Time Factors ; B7-1 Antigen/metabolism* ; Membrane Proteins/immunology* ; Cell Culture Techniques/methods* ; B7-2 Antigen/metabolism* ; Cell Differentiation ; CD11c Antigen/metabolism* ; Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology*

As prepubertal boys do not yet produce spermatozoa, they cannot rely on sperm cryopreservation for fertility preservation before gonadotoxic therapy, such as high-dose alkylating agents or radiotherapy in the case of childhood cancers. According to the current guidelines, cryopreservation of testicular biopsies containing spermatogonial stem cells (SSCs) may be proposed to high-risk patients for potential later therapeutic use to fulfill the patients' wish for a biological child. One promising technique for human in vitro spermatogenesis and in vitro propagation of human SSCs is microfluidic (MF) culture, in which cells or tissues are subjected to a continuous flow of medium. This provides exact control over such parameters as nutrient content and gradients, as well as the removal of waste metabolites. While MF has been shown to maintain tissues and cell populations of organs for longer than conventional in vitro culture techniques, it has not been widely used for testicular in vitro culture. MF could advance human testicular in vitro culture and is also applicable to reprotoxicity studies. This review summarizes the findings and achievements of testis-on-chip (ToC) setups to date and discusses the benefits and limitations of these for spermatogenesis in vitro and toxicity assessment.
Humans ; Male ; Spermatogenesis/physiology* ; Testis/cytology* ; Cryopreservation ; Cell Culture Techniques/methods* ; Microfluidics/methods* ; Animals

OBJECTIVE: To investigate the role of extracellular vesicles (EVs) derived from placental tissue and placental mesenchymal stem cells in supporting the growth and function of adult hematopoietic stem and progenitor cells (HSPCs), so as to optimize their culture system. METHODS: EVs were isolated from mouse placental tissue (PL-EV) and placental mesenchymal stem cells (PL-MSC-EV). These EVs were co-cultured with 3 000 adult bone marrow LKS⁺ (lineage^- c-Kit⁺ Sca-1⁺ ) cells for 72 hours at concentrations of 0, 1, 10, 50, 100, and 200 μg/ml. The proportion and absolute count of LKS⁺ cells after co-culture were analyzed by flow cytometry, while their self-renewal and multi-lineage differentiation potential were evaluated using colony-forming unit (CFU) assays. RESULTS: Compared to the blank control group, the proportion of LKS⁺ cells were significantly increased in PL-EV groups at concentrations ≥10 μg/ml after 72 hours of co-culture. Notably, LKS⁺ cells co-cultured at the concentration of 10 μg/ml exhibited the highest absolute count (899±171) and the highest proportion of LT-HSCs (LKS⁺ CD135^- CD34^-) (0.67%±0.07%). In the PL-MSC-EV co-culture system, the absolute count of LKS⁺ cells peaked at the concentration of 1 μg/ml (1011±99 cells), though the proportion of LT-HSCs was relatively low (0.15%±0.05%). The comparison between these two culture systems revealed that PL-EV at 10 μg/ml and PL-MSC-EV at 1 μg/ml displayed the most pronounced effects on LKS⁺ cell proliferation, but with no significant difference between them. CFU assays showed that, in the PL-EV culture system, the number of LKS⁺ colony formed in 1 and 10 μg/ml groups was not significantly different compared with the blank control group. In contrast, in the PL-MSC-EV system, the highest LKS⁺ colony-forming capacity was observed when co-cultured with 1 μg/ml PL-MSC-EV, while a significant reduction was noted at concentrations above 10 μg/ml. CONCLUSION PL-EV and PL-MSC-EV effectively support the growth and function of HSPCs. And PL-MSC-EV exhibits a superior efficacy in preserving the stemness of LKS⁺ cells, thus suggesting its potential for optimizing culture systems of HSPCs.
Mesenchymal Stem Cells/cytology* ; Extracellular Vesicles ; Placenta/cytology* ; Female ; Animals ; Mice ; Pregnancy ; Hematopoietic Stem Cells/cytology* ; Coculture Techniques ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured

OBJECTIVE: To identify the role of gene silencing or overexpression of Nemo-like kinase (NLK) during the process of neural differentiation of human mesenchymal stem cells (hBMSCs), and to explore the effect of NLK downregulation by transfection of small interfering RNA (siRNA) on promoting neuralized tissue engineered bone regeneration. METHODS: NLK-knockdown hBMSCs were established by transfection of siRNA (the experimental group was transfected with siRNA silencing the NLK gene, the control group was transfected with control siRNA and labeled as negative control group), and NLK-overexpression hBMSCs were established using lentivirus vector transfection technique (the experimental group was infected with lentivirus overexpressing the NLK gene, the control group was infected with an empty vector lentivirus and labeled as the empty vector group). After neurogenic induction, quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression of neural-related gene, and Western blot as well as immunofluorescence staining about several specific neural markers were used to evaluate the neural differentiation ability of hBMSCs.6-week-old male nude mice were divided into 4 groups: ① β-tricalcium phosphate (β-TCP) group, ② β-TCP+ osteogenic induced hBMSCs group, ③ β-TCP+ siRNA-negative control (siRNA-NC) transfection hBMSCs group, ④ β-TCP+ siRNA-NLK transfection hBMSCs group. Four weeks after the subcutaneous ectopic osteogenesis models were established, the osteogenesis and neurogenesis were detected by hematoxylin-eosin (HE) staining, Masson staining and tissue immunofluorescence assay. Statistical analysis was conducted by independent sample t test. RESULTS: After gene silencing of NLK by siRNA in hBMSCs, neural-related genes, including the class Ⅲ β-tubulin (TUBB3), microtubule association protein-2 (MAP2), soluble protein-100 (S100), nestin (NES), NG2 proteoglycan (NG2) and calcitonin gene-related peptide (CGRP), were increased significantly in NLK-knockdown hBMSCs compared with the negative control group(P < 0.05), and the expression levels of TUBB3 and MAP2 of the NLK silencing group were also increased. Oppositely, after NLK was overexpressed using lentivirus vector transfection technique, TUBB3, MAP2, S100 and NG2 were significantly decreased in NLK-overexpression hBMSCs compared with the empty vector group (P < 0.05), and the expression level of TUBB3 was also decreased. 4 weeks after the subcutaneous ectopic osteogenesis model was established, more mineralized tissues were formed in the β-TCP+ siRNA-NLK transfection hBMSCs group compared with the other three groups, and the expression of BMP2 and S100 was higher in the β-TCP+ siRNA-NLK transfection hBMSCs group than in the other groups. CONCLUSION Gene silencing of NLK by siRNA promoted the ability of neural differentiation of hBMSCs in vitro and promoted neuralized tissue engineered bone formation in subcutaneous ectopic osteogenic models in vivo in nude mice.
Bone Regeneration/genetics* ; Animals ; Mesenchymal Stem Cells/cytology* ; Humans ; RNA, Small Interfering/genetics* ; Tissue Engineering/methods* ; Cell Differentiation ; Mice, Nude ; Gene Silencing ; Mice ; Male ; Protein Serine-Threonine Kinases/genetics* ; Intracellular Signaling Peptides and Proteins/genetics* ; Transfection ; Cells, Cultured ; Lentivirus/genetics*