Therapeutic effect of human umbilical cord mesenchymal stem cells in early traumatic osteonecrosis of the femoral head

Impact of Tissue Factor Gene Knockout on Coagulation Properties of Umbilical Cord-Derived Multipotent Mesenchymal Stromal/Stem Cells

Multipotent mesenchymal stromal/stem cells (MSCs) refer to a population of stem cells that exhibit distinct progenitor cell characteristics including the potential for differentiation into a wide range of cell types. MSCs have become a promising candidate for cell therapy and tissue regeneration due to their unique properties, such as their ability to differentiate into multiple cell types, their capacity for expansion, self-renewal, and immune-regulatory effects. However, reports have brought attention to thrombosis-related complications associated with MSCs therapy in the last decade. As tissue factor (TF) is a powerful coagulation activator expressed by MSCs that stimulates the extrinsic coagulation pathway, we investigated the thrombotic properties of human umbilical cord MSCs (HUCMSCs) after knocking out the TF gene. MSCs populations that obtained from umbilical cord were cultured and expanded in the appropriate medium cell culture. The identity of the MSCs was verified through flow cytometry, and their ability to differentiate into osteogenic and adipogenic lineages. Two gRNAs for Exons 1 and 2 of the TF gene have been designed and cloned into px458 vector's backbone (pSpCas9 (BB)-2A-GFP). Following transfecting of gRNAs into HUCMSCs and successfully knocking out the TF gene using GAP-PCR, the impact of normal and knockout HUCMSCs on coagulation was assessed through prothrombin time (PT), D-dimer level, clotting time (CT), and turbidity assay. Furthermore, the impact of TF knockout (TFKO) on MMP19 expression was assessed. Our results revealed that the PT was prolonged and D-dimer level was decreased in TFKO group compared to normal HUCMSCs. These findings suggest that TF gene plays a crucial role in regulating coagulation in HUCMSCs. Also, a significant reduction in MMP19 expression was observed within the TFKO group.

Multi-sequence MRI-based radiomics: An objective method to diagnose early-stage osteonecrosis of the femoral head

OBJECTIVES

This study investigated the use of radiomics for diagnosing early-stage osteonecrosis of the femoral head (ONFH) by extracting features from multiple MRI sequences and constructing predictive models.

MATERIALS AND METHODS

We conducted a retrospective review, collected MR images of early-stage ONFH (102 from institution A and 20 from institution B) and healthy femoral heads (102 from institution A and 20 from institution B) from two institutions. We extracted radiomics features, handled batch effects using Combat, and normalized features using z-score. We employed the Least absolute shrinkage and selection operator (LASSO) algorithm, along with Max-Relevance and Min-Redundancy (mRMR), to select optimal features for constructing radiomics models based on single, double, and multi-sequence MRI data. We evaluated performance using receiver operating characteristic (ROC) and precision-recall (PR) curves, and compared area under curve of ROC (AUC-ROC) values with the DeLong test. Additionally, we studied the diagnostic performance of the multi-sequence radiomics model and radiologists, compared the diagnostic outcomes of the model and radiologists using the Fisher exact test.

RESULTS

We studied 122 early-stage ONFH and 122 normal femoral heads. The multi-sequence model exhibited the best diagnostic performance among all models (AUC-ROC, PR-AUC for training set: 0.96, 0.961; validation set: 0.96, 0.97; test set: 0.94, 0.94), and it outperformed three resident radiologists on the external testing group with an accuracy of 87.5 %, sensitivity of 85.00 %, and specificity of 90.00 % (p < 0.01), highlighting the robustness of our findings.

CONCLUSIONS

Our study underscored the novelty of the multi-sequence radiomics model in diagnosing early-stage ONFH. By leveraging features extracted from multiple imaging sequences, this approach demonstrated high efficacy, indicating its potential to advance early diagnosis for ONFH. These findings provided important guidance for enhancing early diagnosis of ONFH through radiomics methods, offering new avenues and possibilities for clinical practice and patient care.

Designing and synthesis of injectable hydrogel based on carboxymethyl cellulose/carboxymethyl chitosan containing QK peptide for femoral head osteonecrosis healing

Femoral head necrosis is a debilitating disorder that typically caused by impaired blood supply to the hip joint. In this study, a novel injectable hydrogel based on Oxidized Carboxymethyl Cellulose (OCMC)-Carboxymethyl Chitosan (CMCS) polymers containing an angiogenesis stimulator peptide (QK) with a non-toxic crosslinking interaction (Schiff based reaction) was synthesized to enhance angiogenesis following femoral head necrosis in an animal model. The physicochemical features of fabricated injectable hydrogel were analyzed by FTIR, swelling and degradation rate, rheometry, and peptide release. Also, the safety and efficacy were evaluated following an in vitro hydrogel injection study and an avascular necrosis (AVN) animal model. According to the results, the hydrogel exhibited an appropriate swelling ratio and water uptake (>90 %, 24 h) as well as a suitable degradation rate over 21 days accompanied by a continuous peptide release. Also, data showed that hydrogels containing QK peptide boosted the proliferation, differentiation, angiogenesis, and osteogenic potential of both Bone Marrow mesenchymal Stem Cells (BM-MSCs) and human umbilical vein endothelial cells (HUVECs) (****p < 0.0001 and ***p < 0.001, respectively). Furthermore, molecular and histological evaluations significantly demonstrated the overexpression of Runx2, Osteocalcin, Collagen I, VEGF and CD34 genes (**p < 0.01 and ***p < 0.001, respectively), and also femoral head necrosis was effectively prohibited, and more blood vessels were detected in defect area by OCMC-CMCS hydrogel containing QK peptide (bone trabeculae >9000, ***p < 0.001). In conclusion, the findings demonstrate that OCMC-CMCS-QK injectable hydrogel could be considered as an impressive therapeutic construct for femoral head AVN healing.

Stimulated Human Umbilical Cord Mesenchymal Stem Cells Enhance the Osteogenesis and Cranial Bone Regeneration through IL-32 Mediated P38 Signaling Pathway

Objective

Our previous study found that it could significantly increase the expression of IL32 after stimulating the human umbilical cord mesenchymal stem cells (S-HuMSCs). However, its role on the osteogenesis and cranial bone regeneration is still largely unknown. Here, we investigated the possible mechanism of this effect. Material and Methods. A series of experiments, including single-cell sequencing, flow cytometry, quantitative real-time polymerase chain reaction, and western blotting, were carried out to evaluate the characteristic and adipogenic-osteogenic differentiation potential of IL-32 overexpression HuMSCs (IL-32highHuMSCs) through mediating the P38 signaling pathway. Moreover, a rat skull bone defect model was established and treated by directly injecting the IL-32highHuMSCs to conduct its role on the cranial bone regeneration.

Results

In total, it found that compared to HuMSCs, IL32 was significantly increased and promoted the osteogenic differentiation (lower expressions of PPARγ, Adiponectin, and C/EBPα, and increased expressions of RUNX2, ALP, BMP2, OPN, SP7, OCN, and DLX5) in the S-HuMSCs (P < 0.05). Meanwhile, the enhanced osteogenic differentiation of HuMSCs was recovered by IL-32 overexpression (IL-32highHuMSCs) through activating the P38 signaling pathway, like as the S-HuMSCs (P < 0.05). However, the osteogenic differentiation potential of IL-32highHuMSCs was significantly reversed by the P38 signaling pathway inhibitor SB203580 (P < 0.05). Additionally, the HuMSCs, S-HuMSCs, and IL-32highHuMSCs all presented adipogenic-osteogenic differentiation potential, with higher levels of CD73, CD90, and CD105, and lower CD14, CD34, and CD45 (P > 0.05). Furthermore, these findings were confirmed by the rat skull bone defect model, in which the cranial bone regeneration was more pronounced in the IL-32highHuMSCs treated group compared to those in the HuMSCs group, with higher expressions of RUNX2, ALP, BMP2, and DLX5 (P < 0.05).

Conclusion

We have confirmed that S-HuMSCs can enhance the osteogenesis and cranial bone regeneration through promoting IL-32-mediated P38 signaling pathway, which is proved that IL-32 may be a therapeutic target, or a biomarker for the treatment of cranial bone injuries.

Stem cell therapy combined with core decompression versus core decompression alone in the treatment of avascular necrosis of the femoral head: a systematic review and meta-analysis

INTRODUCTION

Accumulated clinical trials had been focused on stem cell therapy in combination of core decompression (CD) in the treatment of avascular necrosis of the femoral head (ANFH). Nonetheless, the results were inconclusive. Here, we performed a systematic review and meta-analysis of previous randomized controlled trials (RCTs) and retrospective studies to assess whether combined stem cell augmentation with CD improved the outcomes of ANFH compared with CD alone.

METHODS

The current study included 11 RCTs and 7 retrospective studies reporting the clinical outcomes of a total of 916 patients and 1257 hips. 557 and 700 hips received CD and CD plus stem cell therapy, respectively. To compare CD with CD plus stem cell therapy, we examined the clinical evaluating scores, the occurrence of the femoral head, radiologic progression and conversion to total hip arthroplasty (THA).

RESULTS

Only 10 studies reported significantly greater improvement in hip functions while combining stem cell procedure with CD. The pooled results in subgroup analysis indicated that stem cell group had a lower collapse rate on a mid-term basis (P = 0.001), when combined with mechanical support (P < 0.00001), and with extracted stem cells (P = 0.0002). Likewise, stem cell group had a lower radiographic progression rate at 2- to 5-year follow-up [P = 0.003], when combined with structural grafting (P < 0.00001), and with extracted stem cells (P = 0.004). Stem cell therapy resulted in an overall lower THA conversion rate (P < 0.0001) except that at a follow-up longer than 5 years.

CONCLUSION

Stem cell therapy combined with core decompression was more effective in preventing collapse, radiographic progression and conversion to THA. Trial Registration The current protocol has been registered in PROSPERO with the registration number: CRD42023417248.